Title of Invention	METHOD AND DEVICE FOR CONTROLLING POWER AMPLIFICATION
Abstract	A method and an NE for controlling power amplification are provided. The method for controlling power amplification includes: outputting a voltage signal according to the state of an NE: applying the voltage signal to a grid electrode or a base electrode of at least one power amplifier transistor in a power amplifier. Thus, static power dissipation of the power amplifier tan be eliminated when no RE power is output, and the efficiency of the power amplifier can be improved by using the above method and NE.

Title of Invention

METHOD AND DEVICE FOR CONTROLLING POWER AMPLIFICATION

Abstract

A method and an NE for controlling power amplification are provided. The method for controlling power amplification includes: outputting a voltage signal according to the state of an NE: applying the voltage signal to a grid electrode or a base electrode of at least one power amplifier transistor in a power amplifier. Thus, static power dissipation of the power amplifier tan be eliminated when no RE power is output, and the efficiency of the power amplifier can be improved by using the above method and NE.

Full Text	FIELD OF THE INVENTION The present invention relates to the field of communications, and more particularly to a method and a device for controlling power amplification. BACKGROUND OF THE INVENTION A radio frequency (RF) power amplifier is a key component of a network equipment (NE) in a radio communication system. The RF power amplifier is substantially an energy converter, which converts Direct Current (DC) energy of a power source into RF energy for transmission through an antenna. A ratio of the RF power to the DC power provided by the power source is referred to as the efficiency ? of the power amplifier, and the efficiency is an important factor of the power amplifier. Taking the power amplifier in a base station for example, the efficiency is directly associated with factors such as the power source, heat dissipation, size. fans, and noises of the base station system. A high efficiency of the power amplifier improves the reliability of the base station system and reduces the cost of the base station equipment. For a telecommunication operator, a high efficiency of the power amplifier can effectively reduce the cost of system operation and subsequent maintenance. The efficiency ? of a power amplifier is calculated according to the following formulae: where Vdd is a voltage provided by a DC power source, and Id is a current provided by the DC power source. In the whole power conversion process, a part of the DC energy is inevitably converted into heat, which will be wasted. Therefore, the actual efficiency of the power amplifier is always lower than 100%. In a current base station power amplifier, to consider the efficiency and linearity indexes comprehensively, a static working point of the power amplifier is normally set to Class A or Class AB. that is. a static working current of the power amplifier Idq>0A Taking a laterally diffused metal oxide semiconductor (LDMOS) for example, the LDMOS is a power amplifier transistor widely applied at present. If a voltage bias of a power amplifier using the power amplifier transistor is in Class AB. and the power amplifier is in a saturated output state, the efficiency is the highest. However, with the decrease of the output power, the efficiency will be reduced gradually. That is, the ratio of the heat converted from the DC energy provided by the power source will rise with the decrease of the efficiency of the power amplifier. When the power amplifier does not output any RF power, the dissipated DC power is as follows: for the base station system, the state in which the power amplifier does not output any RF power appears frequently (for example, when no subscriber accesses the system). According to the above analysis, at this time, for a common Class A or Class AB amplifier, the static power is wasted, and the overall efficiency of the power amplifier is lowered. To improve the overall efficiency of the power amplifier, the following solution is adopted in the prior art. When the power amplifier is in a state with no RF power output, a voltage of a drain electrode of the power amplifier transistor in the power amplifier is adjusted to 0 V. It is known from Formula [3] that, at this time, Power-dc = 0W, i.e. the dissipated DC power is 0 W. Though the overall efficiency of the power amplifier is increased to some extent by using the above method, the inventors found the following problems from the solution. 1) The response time is long, the solution is applicable to few scenarios only, and the improvement to the efficiency of the power amplifier is limited. Normally the drain electrode of the power amplifier transistor operates in the state of high voltage (for example. 28 V) and large current (for example. 10 A), so the power supply unit thereof must be a power source capable of providing a high power. Limited by factors such as the charging and discharging of high-capacitance capacitors and the soft-start mechanism to ensure security, the time for establishing or disabling the output voltage of such a power source is often several seconds or even several tens of seconds. However, in normal situations, time periods required by services of the base station system are much shorter than one second. For example, in a Global System for Mobile Communications (GSM), the timeslot period of each user is only 577 us. Subscribers may access (the power amplifier needs to switch on) or not access (the power amplifier needs to switch off) the GSM system in a timeslot period, while the solution of controlling the voltage of a drain electrode cannot track such a fast change. To ensure normal communications, the voltage on the drain port of the power amplifier transistor must remain at the normal operating voltage without changes for a long time, and thus a part of the static power will be dissipated In view of the above, the solution of controlling the voltage of a drain electrode is applicable to very few scenarios in practice. Normally, this solution is adopted only when no subscriber accesses the system for a long time at night. Therefore, the improvement to the efficiency of the power amplifier is unobvious. and the power-saving effect is limited. 2) The control circuit is complicated with a high cost and low reliability. The solution of controlling the voltage of a drain electrode deals with signals with a high voltage and large current, so many high-power elements are needed. Therefore, the circuit implementation is complicated, the cost is high, and the reliability is low, which may easily cause potential quality problems. SUMMARY OF THE INVENTION Accordingly, the embodiments of present invention provide a method and a device for controlling power amplification, a base station, and a terminal, so as to improve the efficiency of a power amplifier by reducing static power dissipation in a time period without output power. In an embodiment of the present invention, a method for controlling power amplification is provided. The method includes the following steps. Outputting a voltage signal according to the state of an NE; Applying the voltage signal to a grid electrode or a base electrode of at least one power amplifier transistor in a power amplifier. In an embodiment of the present invention, a transmitter is provided. The transmitter includes a main control unit, a voltage control unit, and a power amplifier unit. The main control unit is adapted to obtain the state of an NE where the transmitter is located, and send a voltage control signal according to the state. The voltage control unit is adapted to output a voltage signal according to the voltage control signal received from the main control unit. The power amplifier unit is adapted to switch on or switch off according to the voltage signal applied to a grid electrode or a base electrode of at least one power amplifier transistor therein by the voltage control unit. In an embodiment of the present invention, a base station is provided. The base station includes a main control unit, a voltage control unit, and a power amplifier unit. The main control unit is adapted to obtain the state of the base station, and send a voltage control signal according to the state. The voltage control unit is adapted to output a voltage signal according to the voltage control signal received from the main control unit. The power amplifier unit is adapted to switch on or switch off according to the voltage signal applied to a grid electrode or a base electrode of at least one power amplifier transistor in the power amplifier unit. In an embodiment of the present invention, a terminal is provided. The terminal includes a main control unit, a voltage control unit, and a power amplifier unit. The main control unit is adapted to obtain the state of the terminal, and send a voltage control signal according to the state. The voltage control unit is adapted to output a voltage signal according to the voltage control signal received from the main control unit. The power amplifier unit is adapted to switch on or switch off according to the voltage signal applied to a grid electrode or a base electrode of at least one power amplifier transistor therein by the voltage control unit. In an embodiment of the present invention, a device for controlling power amplification is provided. The device includes a main control unit and a voltage control unit. The main control unit is adapted to obtain the state of an equipment, and send a voltage control signal according to the stale. The voltage control unit is adapted to output a voltage signal to a grid electrode or a base electrode of at least one power amplifier transistor in a power amplifier unit according to the voltage control signal. Compared with the prior art, the embodiments of the present invention achieve the following beneficial effects. The response time is short, the solution is applicable to more scenarios, and the power amplification efficiency is improved to the maximum extent. The grid electrode of the power amplifier transistor normally operates in the state of low voltage (for example. 3 V) and small current (for example. 5 mA). the circuit does not have capacitors with high capacitance, and the charging/discharging time is at us level or even lower. Therefore, the power amplifier transistor can switch on or switch off at the same speed, which is advantageous to a fast response to the control signal. Through the control over the grid electrode or the base electrode of the power amplifier transistor, static power dissipation at a timeslot level is reduced, so as to avoid energy dissipation to the maximum extent. The control circuit is simple, the cost is low, and the reliability is high. The voltage control unit processes low-voltage and small-current signals. The circuit implementation is simple, the cost is low. and the reliability is high. BRIEF DESCRIPTION OF THE DRAWINGS FIG 1 is a flow chart of a method for controlling power amplification according to a first embodiment of the present invention; FIG. 2 is a schematic view of the relationship between RF power output of a power amplifier and limeslots according to the first embodiment of the present invention; FIG. 3 is a schematic view of the relationship between power dissipation of a conventional Class AB power amplifier in the prior art and timeslots; FIG. 4 is a schematic view of the relationship between power dissipation of the power amplifier and timeslots according to the first embodiment of the present invention; FIG. 5 is a schematic view of a system for controlling power amplification according to a second embodiment of the present invention, in which a voltage control unit is connected to a grid of a power amplifier transistor; FIG. 6 is a schematic view of a main control unit according to the second embodiment of the present invention; FIG. 7 is a schematic view of the system for controlling power amplification according to the second embodiment of the present invention, in which the voltage control unit is connected to grids of two power amplifier transistors; FIG. 8 is a schematic view of a system for controlling power amplification according to a third embodiment of the present invention, in which a voltage control unit is integrated in a main control unit: FIG. 9 is a schematic view of a system for controlling power amplification according to a fourth embodiment of the present invention, in which a voltage control unit is integrated in a power amplifier; FIG. 10 is a schematic view of a system for controlling power amplification according to a fifth embodiment of the present invention, in which power amplifiers are operated independently or connected in parallel in operation; and FIG. 11 is a schematic view of a system for controlling power amplification according to a sixth embodiment of the present invention, in which power amplifiers are connected in scries in operation. DETAILED DESCRIPTION OF THE EMBODIMENTS In the embodiments of the present invention, a voltage signal is output to a grid electrode or a base electrode of a power amplifier transistor according to the state of an NE, and the power amplifier transistor can switch on or switch off according to the state of the NE under the control of the voltage signal, so as to improve the efficiency of a power amplifier. The technical solutions of the present invention are described in detail below in the embodiments with reference to some accompanying drawings. A method for controlling power amplification is provided in a first embodiment of the present invention. Referring to FIG. 1, the method includes the following steps. Step 8101. outputting a voltage signal according to the state of an NE. In this step, information related to the NE is obtained firstly. The information includes signaling or service information or external control signal or internal clock signal of the NE. and the state of the NE can be determined according to one or multiple combinations of the information. The NE may be in an Idle or a Busy state. The Idle state indicates that the NE is not required to output an RF signal, for example, the NE is not accessed by any subscriber or in an idle timeslot. or receives a control signal for enabling the power amplifier to switch off. The Busy state indicates that the NE is required to output an RF signal, for example, the NE is accessed by subscribers, in a non-idle timeslot. or receives a control signal for enabling the power amplifier to switch on. Taking a base station for example, when a terminal accesses the base station, if a channel type assigned in the signaling is a main broadcast control channel (BCCH) or a packet data traffic channel (PDTCH). it is determined that the NE is in the Busy state, that is, the NE needs to output an RF signal. After the state of the NE is obtained, the voltage signal is output according to the state. When the system is in the Busy state, the voltage signal corresponding to the Busy state is output: and when the system is in the Idle state, the voltage signal corresponding to the Idle state is output. The value of the voltage signal varies with different power amplifier transistors. For example, if the power amplifier transistor is an N-channel LDMOS, the voltage signal corresponding to the Busy state may be 2 V to 5 V, and the voltage signal corresponding to the Idle state may be 0 V to 2 V. Besides, if the power amplifier transistor is an N-channel depletion-mode gallium arsenide metal-semiconductor field effect transistor (GaAs MESFET), the voltage signal corresponding to the Busy state may be -4 V to 0 V, and the voltage signal corresponding to the Idle state may be -5 V to -4 V. Step 8102. applying the voltage signal to a grid electrode or a base electrode of at least one power amplifier transistor in a power amplifier When the NE is in the Busy state, the voltage signal corresponding to the Busy state is applied to the grid electrode or the base electrode of one or more power amplifier transistors in ;.hc power amplifier. At this time, the power amplifier transistor works in an amplification range, and the power amplifier has RF power output. When the NE is in the Idle state, the voltage signal corresponding to the Idle state is applied to the grid electrode or the base electrode of one or more power amplifier transistors in the power amplifier. At this time, the power amplifier transistor switches off with no RF power output, and thus does not have static power dissipation. After the method of the present invention is described in the above embodiment, the difference between DC power dissipation of the power amplifier in the method of the present invention and that of the power amplifier in the prior art is given below with specific examples. It is assumed that FIG. 2 is a schematic view of the relationship between the RF power output of a Class A or Class AB power amplifier in eight timeslot periods and timeslots according to the first embodiment of the present invention, in which the Pf axis represents the RF output power, and the t axis represents the timeslots. The timeslots 2, 4, and 6 are idle timeslots. during which the power amplifier does not have RF power output; while the timeslots 1. 3. 5. 7. and 8 are non-idle timeslots. during which the power amplifier has RF power output. FIG. 3 is a schematic view of the relationship between the power dissipation of a conventional Class AB power amplifier in the prior art and the timeslots in the RF power output state as shown in FIG. 2. In FIG. 3, the Pq1 axis represents the power dissipation of the power amplifier, the Vg1 axis represents a grid electrode bias voltage of the power amplifier transistor in the power amplifier, and the dashed line Vgsl represents a current grid bias voltage of the power amplifier transistor. As shown in FIG. 3, Vgsl is constant (normally between 2 V and 5 V). and the power dissipation is not zero in the idle timeslots 2. 4. and 6. FIG. 4 is a schematic view of the relationship between the power dissipation of the Class A or Class AB power amplifier utilizing the method embodiment of the present invention and the timeslots in the RF power output state as shown in FIG. 2. In FIG. 4. the Pq2 axis represents the power dissipation of the power amplifier, the Vg2 axis represents a grid electrode bias voltage of the power amplifier transistor in the power amplifier, and the dashed line Vgs2 represents a current grid electrode bias voltage of the power amplifier transistor. As shown in FIG. 4. Vgs2 varies with the state of the timeslots. In the idle timeslots 2, 4. and 6. Vgs2 is between 0 V and 2 V. the power amplifier transistor switches off, and (he power dissipation of the power amplifier is zero; while in the non-idle timeslots 1, 3. 5, 7, and 8. Vgs2 is between 2 V and 5 V, the power amplifier transistor works in an amplification range, and the power amplifier has RF power output. If the power amplifier transistor in the power amplifier is a bipolar junction transistor (BJT). the efficiency of the power amplifier can still be improved by using the above method, and the difference lies in that Vgs2 represents a base bias voltage of the BJT, and the value of Vgs2 in the idle and non-idle timeslots can be adjusted according to specific parameters of the transistor. As described above, the voltage of the voltage signal (for example, Vgs2) is relatively low, so that the voltage control circuit does not need high-capacitance capacitors or high-inductance inductors, and the response time can meet the requirements for the timeslot period of the subscribers. By using the method embodiment of the present invention, the power dissipation of the power amplifier is much lower than that of the conventional Class AB power amplifier in the prior art, so as to significantly improve the efficiency of the power amplifier. The method for controlling power amplification is applicable to an RF transmitter, and is also applicable to an NE including, but not limited to, a base station, a wireless terminal, a server a switch, and a base station controller. A system lor controlling power amplification is provided in a second embodiment of the present invention. Referring to FIG. 5, the system includes a main control unit 200, a voltage control unit 210. and a power amplifier unit, in which the power amplifier unit includes a power amplifier 220. Referring to FIG. 6. the main control unit 200 is adapted to obtain the state of an NE. and send a voltage control signal according to the state. The main control unit 200 includes an information acquisition module 202, a state acquisition module 204, and a signal sending module 206. The information acquisition module 202 is adapted to acquire information related to the NE through a port A21. The information includes signaling or service information or external control signals or internal clock signals of the NE. Priorities of the signals may be set in the main control unit, for example, the priority of the external control signals is set to the highest, and thus, when a fault alarm signal or a signal for forcedly turning off the transmitter or power amplifier is received, even if the NE is in the non-idle timeslots as indicated by the signaling, the main control unit still determines the state of the NE as Idle according to the priority. The state acquisition module 204 is adapted to determine a current state of the NE according to the above information. The NE may be in an Idle state or a Busy state. The Idle stale indicates that the NE is not required to output an RF signal, for example, the NE is not accessed by any subscriber, in an idle timeslot, or receives a control signal for enabling the power amplifier to switch off. The Busy state indicates that the NE is required to output an RF signal, for example, the NE is accessed by subscribers, in a non-idle timeslot. or receives a control signal for turning on the power amplifier. The signal sending module 206 is adapted to send the voltage signal according to the state of the NE. For example, the voltage control signal corresponding to the Idle state is represented by a logic voltage "0". and the voltage control signal corresponding to the Busy state is represented by a logic voltage "1". Further, an inverse logic expression may also be adopted, that is the voltage control signal corresponding to the Idle state is represented by a logic voltage "1", and the voltage control signal corresponding to the Busy state is represented by a logic voltage "0". The voltage control signal is output from a port A22. The main control unit 200 may be an integrated chip or a functional module of an integrated chip, for example, a functional module integrated in a control chip of a wireless terminal such as a mobile phone. The main control unit 200 may also be a part of a base station controller, and the voltage control signal is directly sent to a transmitter on a base station side through a signaling channel by the base station controller. The main control unit 200 may also be directly integrated on a board of a transmitter. The voltage control unit 210 is connected to the main control unit 200, and adapted to receive the voltage control signal from the main control unit 200 through a port B21, obtain the voltage signal according to the voltage control signal, and apply the obtained voltage signal to a grid electrode or a base electrode of a power amplifier transistor 221 in the power amplifier 220 through a port B22. The value of the voltage signal varies for different power amplifier transistors. For example, when the power amplifier transistor is an N-channel LDMOS. the voltage signal corresponding to the voltage control signal "1" (the Busy state) may be 2 V to 5 V. and the voltage signal corresponding to the voltage control signal "0" (the Idle state) may be 0 V to 2 V. When the power amplifier transistor is an N-channel depletion-mode GaAs MESFET, the voltage signal corresponding to the voltage control signal "1" (the Busy state) may be -4 V to 0 V, and the voltage signal corresponding to the voltage control signal "0" (the Idle state) may be -5 V to -4 V. The voltage control unit may be formed by an analog switch circuit or a digital-to-analog converter circuit. The voltage control unit may be set separately or integrated in the main control unit as a functional module. The power amplifier 220 is adapted to switch on or switch off according to the bias voltage signal applied to the grid electrode or a base electrode of the power amplifier transistor 221 therein. A port C21 of the power amplifier 220 is adapted to receive an RF signal, a port C22 is adapted to connect a constant power supply voltage Vdd, and a port C23 is adapted to output the RF signal. The power amplifier 220 may be a Class A or Class AB amplifier, and the power amplifier transistor 221 therein includes, but is not limited to. an LDMOS, a GaAs MESFET. a BJT. a junction Held effect transistor (JFET). or a gallium nitride (GAN) transistor. When the power amplifier is formed by multiple power amplifier transistors, the voltage control unit enables the power amplifier to switch on or switch off by controlling the grid voltage or base voltage of the one or multiple power amplifier transistors in the power amplifier. As shown in FIG. 7, a main control unit 300 obtains information related to an NE through a port A31, a port A32 sends a voltage control signal to a port B31 of a voltage control unit 3 10. the voltage control unit 310 responds to the signal, and a port B32 outputs a voltage signal to a grid electrode or a base electrode of a power amplifier transistor 32 1 and a grid electrode or a base electrode of a power amplifier transistor 322 in a power amplifier 320. A port C31 of the power amplifier 320 is adapted to receive an RF signal, a port (32 is adapted to connect a constant power supply voltage Vdd, and a port C33 is adapted to output the RF signal. In practice, the power amplifier transistors connected to and controlled by the voltage control unit may be determined according to the internal structure of the power amplifier. When multiple power amplifier transistors need to be controlled, multiple voltage signals are used, which vary according to specific conditions of the power amplifier. As the voltage control unit processes low-voltage and low-current signals, the circuit structure is simple, and the manufacturing cost is low. Moreover, as the circuit includes fewer components, the stability of the circuit is also improved. The system for controlling power amplification is applicable to an RF transmitter, and is also applicable to an NE such as a base station or a wireless terminal. When the system lor controlling power amplification is applied in the wireless terminal, in order to simplify the equipment connection and improve the integration level, the voltage control unit may he directly integrated in the main control unit, or the main control unit, the voltage control unit, and the power amplifier unit may be integrated in a chip or in a functional module of a chip. A system for controlling power amplification is provided in a third embodiment of the present invention, in which a voltage control unit is integrated in a main control unit. Referring to FIG. 8, the system includes a main control unit 400 and a power amplifier unit, and the power amplifier unit includes a power amplifier 420. A voltage control unit 401 is integrated in the main control unit 400. A port A41 of the main control unit 400 is an information input port adapted to obtain information related to an Nfi. The information includes at least one of signaling, service information, external control signals, and internal clock signals of the NE. A current state of the NE is determined according to the above information. A bias voltage signal is applied to a grid electrode or a base electrode of a power amplifier transistor 421 according to the current state of the NE. The NE may be in an Idle state or a Busy state. The Idle state indicates that the NE is not required to output an RF signal, for example, the NE is not accessed by any subscriber, in an Idle limeslot, or receives a control signal for turning off the power amplifier. The Busy state indicates that the NE is required to output an RF signal, for example, the NE is accessed by subscribers, in a non-idle timeslot, or receives a control signal for turning on the power amplifier. Taking a GSM mobile terminal for example, in the process that the terminal establishes connections, the network side delivers a service channel assignment message, in which sequence numbers of timeslots available to the terminal are specified. The main control unit obtains the message, and determines whether the terminal is in a Busy state according to the message and the internal clock when the specified timeless arrive. The voltage control unit 401 integrated in the main control unit 400 outputs a voltage signal according to the state of the NE. and the voltage signal is applied to the grid electrode or the base electrode of the power amplifier transistor 421 through a port A42. The value of the voltage signal varies for different power amplifier transistors. For example, if the power amplifier transistor is an N-channel LDMOS, the voltage signal corresponding to the Busy state of the NE may be 2 V to 5 V, and the voltage signal corresponding to the Idle state may be 0 V to 2 V. If the power amplifier transistor is an N-channel depletion-mode GaAs MESFET, the voltage signal corresponding to the Busy stale may be -4 V to 0 V. and the voltage signal corresponding to the Idle state may be -5 V to -4 V. The power amplifier 420 is adapted to switch on or switch off according to the voltage signal applied to the grid electrode or the base electrode of the power amplifier transistor 421 therein. A port C41 of the power amplifier 420 is adapted to receive an RF signal, a port C42 is adapted to connect a constant power supply voltage Vdd, and a port C43 is adapted to output the RF signal. The power amplifier 420 may be a Class A or Class AB amplifier, and the power amplifier transistor 421 therein includes, but is not limited to. an LDMOS. a GaAs MESFEL a BJI. a JFET. or a GAN transistor. The voltage control unit is directly integrated in the main control unit. Thus, the integration level of the equipment is improved, the configuration and circuit connection are simplified, and the delay of the control signal is significantly shortened to make the response to the voltage signal more timely. In addition, the function of the main control unit 400 may be realized through a dedicated integrated circuit, a central processing unit (CPU), or a field programmable gate array (FPGA). The system for controlling power amplification is applicable to an RF transmitter, and is also applicable to an NE such as a base station or a wireless terminal. According to actual requirements, the voltage control unit may also be directly integrated in the power amplifier. A system for controlling power amplification is provided in a fourth embodiment of the present invention, in which a voltage control unit is integrated in a power amplifier. Referring to FIG. 9. the system includes a main control unit 500 and a power amplifier 520. A port A3 1 of the main control unit 500 is an information input port adapted to obtain information related to an NE. The information includes at least one of signaling, service information, external control signals, and internal clock signals of the NE. A current state of the NE is determined according to the above information. The NE may be in an Idle state or a Busy state. The Idle state indicates that the NE is not required to output an RF signal, for example, the NE is not accessed by any subscriber, in an idle timeslot, or receives a control signal for turning off the power amplifier. The Busy state indicates that the NE is required to output an RF signal, for example, the NE is accessed by subscribers, in a non-idle timeslot. or receives a control signal for turning on the power amplifier. The main control unit 500 sends a voltage control signal according to the state of the NE. For example, the voltage control signal corresponding to the Idle state is represented by a logic voltage "0", and the voltage control signal corresponding to the Busy state is represented by a logic voltage "1". Further, an inverse logic expression may also be adopted, that is. the voltage control signal corresponding to the Idle state is represented by a logic voltage "1" and the voltage control signal corresponding to the Busy state is represented by a logic voltage "0". The voltage control signal is output from a port A52. The main control unit 500 may be an integrated chip or a functional module of an integrated chip. The main control unit may also be a part of a base station controller, and the voltage control signal is directly sent to a transmitter on a base station side through a signaling channel by the base station controller. The main control unit may also be integrated in a baseband signal processing subsystem of a base station, or directly integrated on a board of a transmitter. A voltage control unit 522 is integrated in the power amplifier 520. A port C54 of the voltage control unit 522 receives the voltage control signal from the main control unit 500. The voltage control unit 522 responds to the voltage control signal, and applies a voltage signal to a grid electrode or a base electrode of a power amplifier transistor 521. The power amplifier transistor switches on or switches off according to the voltage signal. The value of the voltage signal varies for different power amplifier transistors. For example, when the power amplifier transistor is an N-channel LDMOS, the voltage signal corresponding to the voltage control signal "1" (the Busy state) may be 2 V to 5 V, and the voltage signal corresponding to the voltage control signal "0" (the Idle state) may be 0 V to 2 V. If the power amplifier transistor is an N-channel depletion-mode GaAs MESFET, the voltage signal corresponding to the voltage control signal "1" (the Busy state) may be -4 V to 0 V. and the voltage signal corresponding to the voltage control signal "0" (the Idle state) may be -5 V to -4 V. A port C51 of the power amplifier 520 is adapted to receive an RF signal, a port C52 is adapted to connect a constant voltage Vdd of power source, and a port C53 is adapted to output the RF signal. The power amplifier 520 may be a Class A or Class AB amplifier, and the power amplifier transistor 521 therein includes, but is not limited to, an LDMOS, a GaAs MFSELI. a BJL a JEET, or a CAN transistor. The power amplifier 520 may also be an integrated circuit, and the voltage control unit therein is implemented through a digital-to-analog converter circuit or an analog switch circuit. The voltage control unit is integrated in the power amplifier unit (which includes the power amplifier). Thus, the universality of the power amplifier unit is improved. Moreover, as the transmission path of the voltage signal is short, the interference to the voltage signal caused by other signals is effectively prevented. Therefore, this configuration is applicable when the main control unit is at a long distance to the power amplifier. The sytem for controlling power amplification is applicable to an RF transmitter, and is also applicable to an NE such as a base station or a wireless terminal. A system lor controlling power amplification is provided in a fifth embodiment of the present invention, in which multiple power amplifiers are operated independently or connected in parallel in operation. Referring to FIG. 10. the system includes a main control unit 600. a voltage control unit 610, and a power amplifier unit formed by a first power amplifier 620. a second power amplifier 630, and a third power amplifier 640. A port A61 of the main control unit 600 is an information input port adapted to obtain information related to an NE. The information includes at least one of signaling, service information, external control signals, and internal clock signals of the NE. A current state of the NE is determined according to the above information. The NE may be in an Idle state or a Busy state. The Idle state indicates that the NE is not required to output an RF signal, for example, the NE is not accessed by any subscriber, in an idle timeslot, or receives a control signal for turning off the power amplifier. The Busy state indicates that the NE is required to output an RF signal, for example, the NE is accessed by subscribers, in a non-idle timeslot, or receives a control signal lor turning on the power amplifier. The main control unit 600 sends a voltage control signal according to the state of the NE. For example, the voltage control signal corresponding to the Idle state is represented by a logic voltage "0", and the voltage control signal corresponding to the Busy state is represented by a logic voltage "1". Further, an inverse logic expression may also be adopted, that is. the voltage control signal corresponding to the Idle state is represented by a logic voltage " 1". and the voltage control signal corresponding to the Busy state is represented by a logic voltage "0". The voltage control signal is output from a port A62. When the power amplifier unit is formed by multiple power amplifiers, the main control unit outputs multiple independent voltage control signals, and the logic expression of each voltage control signal is the same as the preceding description. The main control unit 600 may be an integrated chip or a functional module of an integrated chip. The main control unit may also be a part of a base station controller, and the voltage control signal is directly sent to a transmitter on a base station side through a signaling channel by the base station controller. The main control unit may also be directly integrated on a board of a transmitter. The voltage control unit 610 is connected to the main control unit 600, and adapted to receive the voltage control signals from the main control unit 600 through a port B61, obtain voltage signals according to the voltage control signals, and apply the obtained voltage signals to grid electrodes of the power amplifier transistors 621, 631, and 641 or base electrodes of the power amplifier transistors 621. 631. and 641 through a port B62, respectively. Here, the port B62 can output three independent voltage signals to control the three power amplifiers independently, or output only one voltage signal to control the three power amplifiers uniformly. The value of the voltage signals varies for different power amplifier transistors. For example, when the power amplifier transistors are N-channel LDMOSs. the voltage signals corresponding to the voltage control signals "1" (the Busy state) may be 2 V to 5 V. and the voltage signals corresponding to the voltage control signals '0" (the Idle state) may be 0 V to 2 V. If the power amplifier transistors are N-channel depletion-mode GaAs MESFETs. the voltage signals corresponding to the voltage control signals "1" (the Busy state) may be -4 V to 0 V, and the voltage signals corresponding to the voltage control signals "0" (the Idle slate) may be -5 V to -4 V. The voltage control Link may be formed by an analog switch circuit or a digital-to-analog convener circuit. The voltage control unit may be set separately or integrated in the main control unit or the power amplifier unit as a functional module. When the fust power amplifier 620, the second power amplifier 630, and the third power amplifier 640 operate independently, ports C61, C64, and C67 receive three independent RF signals, and ports C63, C66. and C69 output three amplified RF signals, respectively. Each of the power amplifiers is adapted to switch on or switch off according to the voltage signal applied to the grid electrode or the base electrode of the power amplifier transfer therein. The first power amplifier 620. the second power amplifier 630, and the third power amplifier 040 may respectively include one or more power amplifier transistors, and ports C62, C65. and C68 thereof are connected to a constant power supply voltage Vdd respectively. When the power amplifiers operate in parallel, the ports C61 ,C64, and C67 receive one RF signal, which is then divided into three signals. The three signals are amplified by the three power amplifiers, then combined by the ports C63, C66, and C69, and output as one RF signal. Each of the power amplifiers is adapted to switch on or switch off according to a bias voltage signal applied to the grid electrode or the base electrode of the power amplifier transistor therein. The first power amplifier 620, the second power amplifier 630. and the third power amplifier 640 may respectively include one or more power amplifier transistors, and the ports C62, C65, and C68 thereof are connected to a constant voltage Vdd of a power source respectively. The main control unit controls, via the voltage signal, the number of the power amplifiers which are in the On state, according to the input RF power, so as to improve the overall efficiency of the power amplifier unit. For example, only one power amplifier switches on when the power of the input RF signal is small, and three power amplifiers are turned on when the power of the input RF signal is large. The three power amplifiers may be controlled uniformly by one voltage signal, so as to double the output power. The first power amplifier 620, the second power amplifier 630, and the third power amplifier 640 may be Class A or Class AB amplifiers, and the power amplifier transistors therein include, but are not limited to, LDMOS, GaAs MESFET, BJT, JFET, or GAN transistors. The main control unit outputs multiple voltage signals through the voltage control unit, which realizes the collective control over multiple power amplifiers, saves the equipment cost, and improves the efficiency of the power amplifiers. The system for controlling power amplification is applicable to an RF transmitter, and is also applicable to an NE such as a base station or a wireless terminal. Sometimes, multiple power amplifiers need to be connected in series in operation to obtain a higher gain. A system for controlling power amplification is provided in a sixth embodiment of the present invention, in which power amplifiers are connected in series in operation. Referring to FIG. 11, the system includes a main control unit 700. a voltage control unit 710, and a power amplifier unit formed by a first power amplifier 720, a second power amplifier 730, and a third power amplifier 740. A port A71 of the main control unit 700 is an information input port adapted to obtain information related to an NE. The information includes at least one of signaling, service information, external control signals, and internal clock signals of the NE. A current state of the NE is determined according to the above information. The NE may be in an Idle state or a Busy state. The Idle state indicates that the NE is not required to output an RF signal, for example, the NE is not accessed by any subscriber, in an idle timeslot. or receives a control signal for turning off the power amplifier. The Busy state indicates that the NE is required to output an RF signal, for example, the NE is accessed by subscribers, in a non-idle timeslot, or receives a control signal for turning on the power amplifier. The main control unit 700 sends a voltage control signal according to the state of the NE. For example, the voltage control signal corresponding to the Idle state is represented by a logic voltage "0". and the voltage control signal corresponding to the Busy state is represented by a logic voltage "1". Further, an inverse logic expression may also be adopted, that is. the voltage control signal corresponding to the Idle state is represented by a logic voltage "1". and the voltage control signal corresponding to the Busy state is represented by a logic voltage '"0". The voltage control signal is output from a port A72. If the power amplifier unit is formed by multiple power amplifiers, the main control unit outputs multiple independent voltage control signals, and the logic expression of each voltage control signal is the same as the preceding description. The main control unit 700 may be an integrated chip or a functional module of an integrated chip. The main control unit may also be a part of a base station controller, and the voltage control signal is directly sent to a transmitter on a base station side through a signaling channel by the base station controller. The main control unit may also be directly integrated on a board of a transmitter. The voltage control unit 710 is connected to the main control unit 700, and adapted to receive the voltage control signals from the main control unit 700 through a port B71, obtain voltage signals according to the voltage control signals, and apply the obtained voltage signals to grid electrodes of the power amplifier transistors 721, 731, and 741 or base electrodes of the power amplifier transistors 721, 731, and 741 through a port B72, respectively. Here, the port B72 can output three independent voltage signals to control the three power amplifiers independently, or output only one voltage signal to control the three power amplifiers uniformly. In addition, for the power amplifiers connected in series, the voltage signal may be applied to individual power amplifiers. For example, in this embodiment, the voltage signal is applied to only the grid electrode of the power amplifier transistor 741 in the last power amplifier 740. The value of the voltage signal varies for different power amplifier transistors. For example. If the power amplifier transistors are N-channel LDMOSs. the voltage signals corresponding to the voltage control signals "1" (the Busy state) may be 2 V to 5 V. and the voltage signals corresponding to the voltage control signals "0" (the Idle state) may be 0 V to 2 V. When the power amplifier transistors are N-channel depletion-mode GaAs MESFETs, the voltage signals corresponding to the voltage control signals "'1" (the Busy state) may be -4 V to 0 V, and the voltage signals corresponding to the voltage control signals "0" (the Idle state) may be -5 V to -4 V. The voltage control unit may be formed by an analog switch circuit or a digital-to-analog converter circuit. The voltage control unit may be set separately or integrated in the main control unit or the power amplifier unit as a functional module. The first power amplifier 720. the second power amplifier 730, and the third power amplifier 740 arc connected in series in operation, and each of the power amplifiers switch on or switch off according to a bias voltage signal applied to the grid electrode or the base electrode of the power amplifier transistor therein. The first power amplifier 720, the second power amplifier 730, and the third power amplifier 740 may respectively include one or more power amplifier transistors. A port C71 is an RF signal input terminal, ports C73 and C74 arc connected, ports C76 and C77 are connected such that the RF signals are amplified on three stages and output from a port C79, and ports C72, C75. and C78 are connected to a constant voltage Vdd ol a power supply respectively. The first power amplifier 720, the second power amplifier 730, and the third power amplifier 740 may be Class A or Class AB amplifiers, and the power amplifier transistors therein include, but are not limited to, LDMOS, GaAs MESFET, BJT, JFET. or GAN transistors. The system for controlling power amplification is applicable to an RF transmitter, and is also applicable to an NE such as a base station or a wireless terminal. A device for controlling power amplification is provided in a seventh embodiment of the present invention. The device includes a main control unit and a voltage control unit. The mail, control unit is adapted to obtain the state of an NE, and send a voltage control signal according to the state. The voltage control unit is adapted to output a voltage signal to a grid electrode or a base electrode of a power amplifier transistor in a power amplifier unit according to the voltage control signal. The main control unit further includes an information acquisition module, a state acquisition module, and a signal sending module. The information acquisition module is adapted to acquire information related to the equipment. The information is signaling, service information, control signals, or internal clock signals. The state acquisition module is adapted to acquire the state of the equipment according to the above information. The signal sending module is adapted to send the voltage signal according to the state of the equipment. Though several specific embodiments of the present invention are disclosed above, the present invention is not limited thereto. Various modifications and variations that can be thought of by persons skilled in the art shall fall within the protective scope of the present invention. WE CLAIM: 1. A method for controlling power amplification, comprising: outputting a voltage signal according to the state of a network equipment, NE; and applying the voltage signal to a grid electrode or a base electrode of at least one power amplifier transistor in a power amplifier. 2. The method of claim 1, further comprising: obtaining information related to the NE, wherein the information includes at least one of signaling, service information, external control signal, internal clock signal; and determining the state of the NE according to the information. 3. The method of claim 2, wherein outputting a voltage signal according to the state of an NE comprises: outputting a first voltage signal according to the state of the NE if the state of the NE is Busy; or outputting a second voltage signal according to the state of the NE if the state of the NE is Idle. 4. The method of claim 3, wherein: the Idle state indicates that the NE is not required to output a radio frequency signal; and the Buss stale indicates that the NE is required to output a radio frequency signal. 5. The method of claim 1, wherein applying the voltage signal to a grid electrode or a base electrode of at least one power amplifier transistor in a power amplifier is in order to enable the power amplifier transistor to switch on or switch off according to the voltage signal. 6. A transmitter, comprising: a main control unit, adapted to obtain a state of a network equipment, NE, where the transmitter is located, and send a voltage control signal according to the state; a voltage control unit, adapted to output a voltage signal according to the voltage control signal received from the main control unit; and a power amplifier unit, adapted to switch on or switch off according to the voltage signal applied to a grid electrode or a base electrode of at least one power amplifier transistor therein by the voltage control unit. 7. The transmitter of claim 6. wherein the main control unit comprises: an information acquisition module, adapted to acquire information related to the NE, the information includes at least one of signaling, service information, external control signals, internal clock signals of the NE: a state acquisition module, adapted to determine the state of the NE according to the above information: and a signal sending module, adapted to send the voltage signal according to the state of the NE. 8. A network equipment. NE, for controlling power amplification, comprising: a main control unit, adapted to obtain a state of the NE, and send a voltage control signal according to the state; a voltage control unit, adapted to output a voltage signal according to the voltage control signal received from the main control unit; and a power amplifier unit, adapted to switch on or switch off according to the voltage signal applied to a grid electrode or a base electrode of at least one power amplifier transistor in the power amplifier unit. 9. The NE of claim 8. wherein the main control unit comprises: an information acquisition module, adapted to acquire information related to the NE, the information includes at least one of signaling, service information, external control signals, internal clock signals; a slate acquisition module, adapted to determine the state of the NE according to the information: and a signal sending module, adapted to send the voltage control signal according to the state of the NE. 10. The NE of claim 8. wherein the power amplifier unit comprises at least two power amplifier, wherein the at least two power amplifier are connected in parallel or in series or operated independently. 11. The NE of claim 8. wherein the NE is a base station or a terminal. A method and an NE for controlling power amplification are provided. The method for controlling power amplification includes: outputting a voltage signal according to the state of an NE: applying the voltage signal to a grid electrode or a base electrode of at least one power amplifier transistor in a power amplifier. Thus, static power dissipation of the power amplifier tan be eliminated when no RE power is output, and the efficiency of the power amplifier can be improved by using the above method and NE.

Full Text

FIELD OF THE INVENTION
The present invention relates to the field of communications, and more particularly
to a method and a device for controlling power amplification.
BACKGROUND OF THE INVENTION
A radio frequency (RF) power amplifier is a key component of a network equipment
(NE) in a radio communication system. The RF power amplifier is substantially an energy
converter, which converts Direct Current (DC) energy of a power source into RF energy for
transmission through an antenna. A ratio of the RF power to the DC power provided by
the power source is referred to as the efficiency ? of the power amplifier, and the
efficiency is an important factor of the power amplifier. Taking the power amplifier in a
base station for example, the efficiency is directly associated with factors such as the power
source, heat dissipation, size. fans, and noises of the base station system. A high
efficiency of the power amplifier improves the reliability of the base station system and
reduces the cost of the base station equipment. For a telecommunication operator, a high
efficiency of the power amplifier can effectively reduce the cost of system operation and
subsequent maintenance.
The efficiency ? of a power amplifier is calculated according to the following
formulae:

where Vdd is a voltage provided by a DC power source, and Id is a current
provided by the DC power source.
In the whole power conversion process, a part of the DC energy is inevitably
converted into heat, which will be wasted. Therefore, the actual efficiency of the power
amplifier is always lower than 100%.
In a current base station power amplifier, to consider the efficiency and linearity
indexes comprehensively, a static working point of the power amplifier is normally set to
Class A or Class AB. that is. a static working current of the power amplifier Idq>0A
Taking a laterally diffused metal oxide semiconductor (LDMOS) for example, the LDMOS
is a power amplifier transistor widely applied at present. If a voltage bias of a power
amplifier using the power amplifier transistor is in Class AB. and the power amplifier is in a
saturated output state, the efficiency is the highest. However, with the decrease of the
output power, the efficiency will be reduced gradually. That is, the ratio of the heat
converted from the DC energy provided by the power source will rise with the decrease of
the efficiency of the power amplifier.
When the power amplifier does not output any RF power, the dissipated DC power
is as follows:

for the base station system, the state in which the power amplifier does not output
any RF power appears frequently (for example, when no subscriber accesses the system).
According to the above analysis, at this time, for a common Class A or Class AB amplifier,
the static power is wasted, and the overall efficiency of the power amplifier is lowered.
To improve the overall efficiency of the power amplifier, the following solution is
adopted in the prior art. When the power amplifier is in a state with no RF power output,
a voltage of a drain electrode of the power amplifier transistor in the power amplifier is
adjusted to 0 V. It is known from Formula [3] that, at this time, Power-dc = 0W, i.e. the
dissipated DC power is 0 W.
Though the overall efficiency of the power amplifier is increased to some extent by
using the above method, the inventors found the following problems from the solution.
1) The response time is long, the solution is applicable to few scenarios only, and
the improvement to the efficiency of the power amplifier is limited.
Normally the drain electrode of the power amplifier transistor operates in the state
of high voltage (for example. 28 V) and large current (for example. 10 A), so the power
supply unit thereof must be a power source capable of providing a high power. Limited by
factors such as the charging and discharging of high-capacitance capacitors and the
soft-start mechanism to ensure security, the time for establishing or disabling the output
voltage of such a power source is often several seconds or even several tens of seconds.
However, in normal situations, time periods required by services of the base station
system are much shorter than one second. For example, in a Global System for Mobile
Communications (GSM), the timeslot period of each user is only 577 us. Subscribers may
access (the power amplifier needs to switch on) or not access (the power amplifier needs to
switch off) the GSM system in a timeslot period, while the solution of controlling the
voltage of a drain electrode cannot track such a fast change. To ensure normal
communications, the voltage on the drain port of the power amplifier transistor must remain
at the normal operating voltage without changes for a long time, and thus a part of the static
power will be dissipated
In view of the above, the solution of controlling the voltage of a drain electrode is
applicable to very few scenarios in practice. Normally, this solution is adopted only when
no subscriber accesses the system for a long time at night. Therefore, the improvement to
the efficiency of the power amplifier is unobvious. and the power-saving effect is limited.
2) The control circuit is complicated with a high cost and low reliability.
The solution of controlling the voltage of a drain electrode deals with signals with a
high voltage and large current, so many high-power elements are needed. Therefore, the
circuit implementation is complicated, the cost is high, and the reliability is low, which may
easily cause potential quality problems.
SUMMARY OF THE INVENTION
Accordingly, the embodiments of present invention provide a method and a device
for controlling power amplification, a base station, and a terminal, so as to improve the
efficiency of a power amplifier by reducing static power dissipation in a time period without
output power.
In an embodiment of the present invention, a method for controlling power
amplification is provided. The method includes the following steps.
Outputting a voltage signal according to the state of an NE;
Applying the voltage signal to a grid electrode or a base electrode of at least one
power amplifier transistor in a power amplifier.
In an embodiment of the present invention, a transmitter is provided. The
transmitter includes a main control unit, a voltage control unit, and a power amplifier unit.
The main control unit is adapted to obtain the state of an NE where the transmitter is
located, and send a voltage control signal according to the state.
The voltage control unit is adapted to output a voltage signal according to the
voltage control signal received from the main control unit.
The power amplifier unit is adapted to switch on or switch off according to the
voltage signal applied to a grid electrode or a base electrode of at least one power amplifier
transistor therein by the voltage control unit.
In an embodiment of the present invention, a base station is provided. The base
station includes a main control unit, a voltage control unit, and a power amplifier unit.
The main control unit is adapted to obtain the state of the base station, and send a
voltage control signal according to the state.
The voltage control unit is adapted to output a voltage signal according to the
voltage control signal received from the main control unit.
The power amplifier unit is adapted to switch on or switch off according to the
voltage signal applied to a grid electrode or a base electrode of at least one power amplifier
transistor in the power amplifier unit.
In an embodiment of the present invention, a terminal is provided. The terminal
includes a main control unit, a voltage control unit, and a power amplifier unit.
The main control unit is adapted to obtain the state of the terminal, and send a
voltage control signal according to the state.
The voltage control unit is adapted to output a voltage signal according to the
voltage control signal received from the main control unit.
The power amplifier unit is adapted to switch on or switch off according to the
voltage signal applied to a grid electrode or a base electrode of at least one power amplifier
transistor therein by the voltage control unit.
In an embodiment of the present invention, a device for controlling power
amplification is provided. The device includes a main control unit and a voltage control
unit.
The main control unit is adapted to obtain the state of an equipment, and send a
voltage control signal according to the stale.
The voltage control unit is adapted to output a voltage signal to a grid electrode or a
base electrode of at least one power amplifier transistor in a power amplifier unit according
to the voltage control signal.
Compared with the prior art, the embodiments of the present invention achieve the
following beneficial effects.
The response time is short, the solution is applicable to more scenarios, and the
power amplification efficiency is improved to the maximum extent. The grid electrode of
the power amplifier transistor normally operates in the state of low voltage (for example. 3
V) and small current (for example. 5 mA). the circuit does not have capacitors with high
capacitance, and the charging/discharging time is at us level or even lower. Therefore, the
power amplifier transistor can switch on or switch off at the same speed, which is
advantageous to a fast response to the control signal. Through the control over the grid
electrode or the base electrode of the power amplifier transistor, static power dissipation at a
timeslot level is reduced, so as to avoid energy dissipation to the maximum extent.
The control circuit is simple, the cost is low, and the reliability is high. The
voltage control unit processes low-voltage and small-current signals. The circuit
implementation is simple, the cost is low. and the reliability is high.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG 1 is a flow chart of a method for controlling power amplification according to a
first embodiment of the present invention;
FIG. 2 is a schematic view of the relationship between RF power output of a power
amplifier and limeslots according to the first embodiment of the present invention;
FIG. 3 is a schematic view of the relationship between power dissipation of a
conventional Class AB power amplifier in the prior art and timeslots;
FIG. 4 is a schematic view of the relationship between power dissipation of the
power amplifier and timeslots according to the first embodiment of the present invention;
FIG. 5 is a schematic view of a system for controlling power amplification according
to a second embodiment of the present invention, in which a voltage control unit is
connected to a grid of a power amplifier transistor;
FIG. 6 is a schematic view of a main control unit according to the second
embodiment of the present invention;
FIG. 7 is a schematic view of the system for controlling power amplification
according to the second embodiment of the present invention, in which the voltage control
unit is connected to grids of two power amplifier transistors;
FIG. 8 is a schematic view of a system for controlling power amplification according
to a third embodiment of the present invention, in which a voltage control unit is integrated
in a main control unit:
FIG. 9 is a schematic view of a system for controlling power amplification according
to a fourth embodiment of the present invention, in which a voltage control unit is
integrated in a power amplifier;
FIG. 10 is a schematic view of a system for controlling power amplification
according to a fifth embodiment of the present invention, in which power amplifiers are
operated independently or connected in parallel in operation; and
FIG. 11 is a schematic view of a system for controlling power amplification
according to a sixth embodiment of the present invention, in which power amplifiers are
connected in scries in operation.
DETAILED DESCRIPTION OF THE EMBODIMENTS
In the embodiments of the present invention, a voltage signal is output to a grid
electrode or a base electrode of a power amplifier transistor according to the state of an NE,
and the power amplifier transistor can switch on or switch off according to the state of the
NE under the control of the voltage signal, so as to improve the efficiency of a power
amplifier.
The technical solutions of the present invention are described in detail below in the
embodiments with reference to some accompanying drawings.
A method for controlling power amplification is provided in a first embodiment of
the present invention. Referring to FIG. 1, the method includes the following steps.
Step 8101. outputting a voltage signal according to the state of an NE.
In this step, information related to the NE is obtained firstly. The information
includes signaling or service information or external control signal or internal clock signal
of the NE. and the state of the NE can be determined according to one or multiple
combinations of the information. The NE may be in an Idle or a Busy state. The Idle
state indicates that the NE is not required to output an RF signal, for example, the NE is not
accessed by any subscriber or in an idle timeslot. or receives a control signal for enabling
the power amplifier to switch off. The Busy state indicates that the NE is required to
output an RF signal, for example, the NE is accessed by subscribers, in a non-idle timeslot.
or receives a control signal for enabling the power amplifier to switch on. Taking a base
station for example, when a terminal accesses the base station, if a channel type assigned in
the signaling is a main broadcast control channel (BCCH) or a packet data traffic channel
(PDTCH). it is determined that the NE is in the Busy state, that is, the NE needs to output
an RF signal.
After the state of the NE is obtained, the voltage signal is output according to the
state. When the system is in the Busy state, the voltage signal corresponding to the Busy
state is output: and when the system is in the Idle state, the voltage signal corresponding to
the Idle state is output. The value of the voltage signal varies with different power
amplifier transistors. For example, if the power amplifier transistor is an N-channel
LDMOS, the voltage signal corresponding to the Busy state may be 2 V to 5 V, and the
voltage signal corresponding to the Idle state may be 0 V to 2 V. Besides, if the power
amplifier transistor is an N-channel depletion-mode gallium arsenide metal-semiconductor
field effect transistor (GaAs MESFET), the voltage signal corresponding to the Busy state
may be -4 V to 0 V, and the voltage signal corresponding to the Idle state may be -5 V to -4
V.
Step 8102. applying the voltage signal to a grid electrode or a base electrode of at
least one power amplifier transistor in a power amplifier
When the NE is in the Busy state, the voltage signal corresponding to the Busy state
is applied to the grid electrode or the base electrode of one or more power amplifier
transistors in ;.hc power amplifier. At this time, the power amplifier transistor works in an
amplification range, and the power amplifier has RF power output. When the NE is in the
Idle state, the voltage signal corresponding to the Idle state is applied to the grid electrode
or the base electrode of one or more power amplifier transistors in the power amplifier. At
this time, the power amplifier transistor switches off with no RF power output, and thus
does not have static power dissipation.
After the method of the present invention is described in the above embodiment, the
difference between DC power dissipation of the power amplifier in the method of the
present invention and that of the power amplifier in the prior art is given below with
specific examples.
It is assumed that FIG. 2 is a schematic view of the relationship between the RF
power output of a Class A or Class AB power amplifier in eight timeslot periods and
timeslots according to the first embodiment of the present invention, in which the Pf axis
represents the RF output power, and the t axis represents the timeslots. The timeslots 2, 4,
and 6 are idle timeslots. during which the power amplifier does not have RF power output;
while the timeslots 1. 3. 5. 7. and 8 are non-idle timeslots. during which the power amplifier
has RF power output.
FIG. 3 is a schematic view of the relationship between the power dissipation of a
conventional Class AB power amplifier in the prior art and the timeslots in the RF power
output state as shown in FIG. 2. In FIG. 3, the Pq1 axis represents the power dissipation of
the power amplifier, the Vg1 axis represents a grid electrode bias voltage of the power
amplifier transistor in the power amplifier, and the dashed line Vgsl represents a current
grid bias voltage of the power amplifier transistor. As shown in FIG. 3, Vgsl is constant
(normally between 2 V and 5 V). and the power dissipation is not zero in the idle timeslots
2. 4. and 6.
FIG. 4 is a schematic view of the relationship between the power dissipation of the
Class A or Class AB power amplifier utilizing the method embodiment of the present
invention and the timeslots in the RF power output state as shown in FIG. 2. In FIG. 4. the
Pq2 axis represents the power dissipation of the power amplifier, the Vg2 axis represents a
grid electrode bias voltage of the power amplifier transistor in the power amplifier, and the
dashed line Vgs2 represents a current grid electrode bias voltage of the power amplifier
transistor. As shown in FIG. 4. Vgs2 varies with the state of the timeslots. In the idle
timeslots 2, 4. and 6. Vgs2 is between 0 V and 2 V. the power amplifier transistor switches
off, and (he power dissipation of the power amplifier is zero; while in the non-idle timeslots
1, 3. 5, 7, and 8. Vgs2 is between 2 V and 5 V, the power amplifier transistor works in an
amplification range, and the power amplifier has RF power output.
If the power amplifier transistor in the power amplifier is a bipolar junction
transistor (BJT). the efficiency of the power amplifier can still be improved by using the
above method, and the difference lies in that Vgs2 represents a base bias voltage of the BJT,
and the value of Vgs2 in the idle and non-idle timeslots can be adjusted according to
specific parameters of the transistor.
As described above, the voltage of the voltage signal (for example, Vgs2) is
relatively low, so that the voltage control circuit does not need high-capacitance capacitors
or high-inductance inductors, and the response time can meet the requirements for the
timeslot period of the subscribers. By using the method embodiment of the present
invention, the power dissipation of the power amplifier is much lower than that of the
conventional Class AB power amplifier in the prior art, so as to significantly improve the
efficiency of the power amplifier.
The method for controlling power amplification is applicable to an RF transmitter,
and is also applicable to an NE including, but not limited to, a base station, a wireless
terminal, a server a switch, and a base station controller.
A system lor controlling power amplification is provided in a second embodiment of
the present invention. Referring to FIG. 5, the system includes a main control unit 200, a
voltage control unit 210. and a power amplifier unit, in which the power amplifier unit
includes a power amplifier 220.
Referring to FIG. 6. the main control unit 200 is adapted to obtain the state of an NE.
and send a voltage control signal according to the state.
The main control unit 200 includes an information acquisition module 202, a state
acquisition module 204, and a signal sending module 206.
The information acquisition module 202 is adapted to acquire information related to
the NE through a port A21. The information includes signaling or service information or
external control signals or internal clock signals of the NE. Priorities of the signals may
be set in the main control unit, for example, the priority of the external control signals is set
to the highest, and thus, when a fault alarm signal or a signal for forcedly turning off the
transmitter or power amplifier is received, even if the NE is in the non-idle timeslots as
indicated by the signaling, the main control unit still determines the state of the NE as Idle
according to the priority.
The state acquisition module 204 is adapted to determine a current state of the NE
according to the above information. The NE may be in an Idle state or a Busy state. The
Idle stale indicates that the NE is not required to output an RF signal, for example, the NE
is not accessed by any subscriber, in an idle timeslot, or receives a control signal for
enabling the power amplifier to switch off. The Busy state indicates that the NE is
required to output an RF signal, for example, the NE is accessed by subscribers, in a
non-idle timeslot. or receives a control signal for turning on the power amplifier.
The signal sending module 206 is adapted to send the voltage signal according to
the state of the NE. For example, the voltage control signal corresponding to the Idle state
is represented by a logic voltage "0". and the voltage control signal corresponding to the
Busy state is represented by a logic voltage "1". Further, an inverse logic expression may
also be adopted, that is the voltage control signal corresponding to the Idle state is
represented by a logic voltage "1", and the voltage control signal corresponding to the Busy
state is represented by a logic voltage "0". The voltage control signal is output from a port
A22.
The main control unit 200 may be an integrated chip or a functional module of an
integrated chip, for example, a functional module integrated in a control chip of a wireless
terminal such as a mobile phone. The main control unit 200 may also be a part of a base
station controller, and the voltage control signal is directly sent to a transmitter on a base
station side through a signaling channel by the base station controller. The main control
unit 200 may also be directly integrated on a board of a transmitter.
The voltage control unit 210 is connected to the main control unit 200, and adapted
to receive the voltage control signal from the main control unit 200 through a port B21,
obtain the voltage signal according to the voltage control signal, and apply the obtained
voltage signal to a grid electrode or a base electrode of a power amplifier transistor 221 in
the power amplifier 220 through a port B22. The value of the voltage signal varies for
different power amplifier transistors. For example, when the power amplifier transistor is
an N-channel LDMOS. the voltage signal corresponding to the voltage control signal "1"
(the Busy state) may be 2 V to 5 V. and the voltage signal corresponding to the voltage
control signal "0" (the Idle state) may be 0 V to 2 V. When the power amplifier transistor
is an N-channel depletion-mode GaAs MESFET, the voltage signal corresponding to the
voltage control signal "1" (the Busy state) may be -4 V to 0 V, and the voltage signal
corresponding to the voltage control signal "0" (the Idle state) may be -5 V to -4 V. The
voltage control unit may be formed by an analog switch circuit or a digital-to-analog
converter circuit. The voltage control unit may be set separately or integrated in the main
control unit as a functional module.
The power amplifier 220 is adapted to switch on or switch off according to the bias
voltage signal applied to the grid electrode or a base electrode of the power amplifier
transistor 221 therein. A port C21 of the power amplifier 220 is adapted to receive an RF
signal, a port C22 is adapted to connect a constant power supply voltage Vdd, and a port
C23 is adapted to output the RF signal.
The power amplifier 220 may be a Class A or Class AB amplifier, and the power
amplifier transistor 221 therein includes, but is not limited to. an LDMOS, a GaAs
MESFET. a BJT. a junction Held effect transistor (JFET). or a gallium nitride (GAN)
transistor.
When the power amplifier is formed by multiple power amplifier transistors, the
voltage control unit enables the power amplifier to switch on or switch off by controlling
the grid voltage or base voltage of the one or multiple power amplifier transistors in the
power amplifier. As shown in FIG. 7, a main control unit 300 obtains information related
to an NE through a port A31, a port A32 sends a voltage control signal to a port B31 of a
voltage control unit 3 10. the voltage control unit 310 responds to the signal, and a port B32
outputs a voltage signal to a grid electrode or a base electrode of a power amplifier
transistor 32 1 and a grid electrode or a base electrode of a power amplifier transistor 322 in
a power amplifier 320. A port C31 of the power amplifier 320 is adapted to receive an RF
signal, a port (32 is adapted to connect a constant power supply voltage Vdd, and a port
C33 is adapted to output the RF signal. In practice, the power amplifier transistors
connected to and controlled by the voltage control unit may be determined according to the
internal structure of the power amplifier. When multiple power amplifier transistors need
to be controlled, multiple voltage signals are used, which vary according to specific
conditions of the power amplifier.
As the voltage control unit processes low-voltage and low-current signals, the
circuit structure is simple, and the manufacturing cost is low. Moreover, as the circuit
includes fewer components, the stability of the circuit is also improved.
The system for controlling power amplification is applicable to an RF transmitter,
and is also applicable to an NE such as a base station or a wireless terminal. When the
system lor controlling power amplification is applied in the wireless terminal, in order to
simplify the equipment connection and improve the integration level, the voltage control
unit may he directly integrated in the main control unit, or the main control unit, the voltage
control unit, and the power amplifier unit may be integrated in a chip or in a functional
module of a chip.
A system for controlling power amplification is provided in a third embodiment of
the present invention, in which a voltage control unit is integrated in a main control unit.
Referring to FIG. 8, the system includes a main control unit 400 and a power amplifier unit,
and the power amplifier unit includes a power amplifier 420.
A voltage control unit 401 is integrated in the main control unit 400. A port A41 of
the main control unit 400 is an information input port adapted to obtain information related
to an Nfi. The information includes at least one of signaling, service information, external
control signals, and internal clock signals of the NE. A current state of the NE is
determined according to the above information. A bias voltage signal is applied to a grid
electrode or a base electrode of a power amplifier transistor 421 according to the current
state of the NE.
The NE may be in an Idle state or a Busy state. The Idle state indicates that the NE
is not required to output an RF signal, for example, the NE is not accessed by any
subscriber, in an Idle limeslot, or receives a control signal for turning off the power
amplifier. The Busy state indicates that the NE is required to output an RF signal, for
example, the NE is accessed by subscribers, in a non-idle timeslot, or receives a control
signal for turning on the power amplifier. Taking a GSM mobile terminal for example, in
the process that the terminal establishes connections, the network side delivers a service
channel assignment message, in which sequence numbers of timeslots available to the
terminal are specified. The main control unit obtains the message, and determines whether
the terminal is in a Busy state according to the message and the internal clock when the
specified timeless arrive.
The voltage control unit 401 integrated in the main control unit 400 outputs a
voltage signal according to the state of the NE. and the voltage signal is applied to the grid
electrode or the base electrode of the power amplifier transistor 421 through a port A42.
The value of the voltage signal varies for different power amplifier transistors. For
example, if the power amplifier transistor is an N-channel LDMOS, the voltage signal
corresponding to the Busy state of the NE may be 2 V to 5 V, and the voltage signal
corresponding to the Idle state may be 0 V to 2 V. If the power amplifier transistor is an
N-channel depletion-mode GaAs MESFET, the voltage signal corresponding to the Busy
stale may be -4 V to 0 V. and the voltage signal corresponding to the Idle state may be -5 V
to -4 V.
The power amplifier 420 is adapted to switch on or switch off according to the
voltage signal applied to the grid electrode or the base electrode of the power amplifier
transistor 421 therein. A port C41 of the power amplifier 420 is adapted to receive an RF
signal, a port C42 is adapted to connect a constant power supply voltage Vdd, and a port
C43 is adapted to output the RF signal.
The power amplifier 420 may be a Class A or Class AB amplifier, and the power
amplifier transistor 421 therein includes, but is not limited to. an LDMOS. a GaAs
MESFEL a BJI. a JFET. or a GAN transistor.
The voltage control unit is directly integrated in the main control unit. Thus, the
integration level of the equipment is improved, the configuration and circuit connection are
simplified, and the delay of the control signal is significantly shortened to make the
response to the voltage signal more timely. In addition, the function of the main control
unit 400 may be realized through a dedicated integrated circuit, a central processing unit
(CPU), or a field programmable gate array (FPGA).
The system for controlling power amplification is applicable to an RF transmitter,
and is also applicable to an NE such as a base station or a wireless terminal.
According to actual requirements, the voltage control unit may also be directly
integrated in the power amplifier.
A system for controlling power amplification is provided in a fourth embodiment of
the present invention, in which a voltage control unit is integrated in a power amplifier.
Referring to FIG. 9. the system includes a main control unit 500 and a power amplifier 520.
A port A3 1 of the main control unit 500 is an information input port adapted to
obtain information related to an NE. The information includes at least one of signaling,
service information, external control signals, and internal clock signals of the NE. A
current state of the NE is determined according to the above information.
The NE may be in an Idle state or a Busy state. The Idle state indicates that the NE
is not required to output an RF signal, for example, the NE is not accessed by any
subscriber, in an idle timeslot, or receives a control signal for turning off the power
amplifier. The Busy state indicates that the NE is required to output an RF signal, for
example, the NE is accessed by subscribers, in a non-idle timeslot. or receives a control
signal for turning on the power amplifier.
The main control unit 500 sends a voltage control signal according to the state of the
NE. For example, the voltage control signal corresponding to the Idle state is represented
by a logic voltage "0", and the voltage control signal corresponding to the Busy state is
represented by a logic voltage "1". Further, an inverse logic expression may also be
adopted, that is. the voltage control signal corresponding to the Idle state is represented by a
logic voltage "1" and the voltage control signal corresponding to the Busy state is
represented by a logic voltage "0". The voltage control signal is output from a port A52.
The main control unit 500 may be an integrated chip or a functional module of an integrated
chip. The main control unit may also be a part of a base station controller, and the voltage
control signal is directly sent to a transmitter on a base station side through a signaling
channel by the base station controller. The main control unit may also be integrated in a
baseband signal processing subsystem of a base station, or directly integrated on a board of
a transmitter.
A voltage control unit 522 is integrated in the power amplifier 520. A port C54 of
the voltage control unit 522 receives the voltage control signal from the main control unit
500. The voltage control unit 522 responds to the voltage control signal, and applies a
voltage signal to a grid electrode or a base electrode of a power amplifier transistor 521.
The power amplifier transistor switches on or switches off according to the voltage signal.
The value of the voltage signal varies for different power amplifier transistors. For
example, when the power amplifier transistor is an N-channel LDMOS, the voltage signal
corresponding to the voltage control signal "1" (the Busy state) may be 2 V to 5 V, and the
voltage signal corresponding to the voltage control signal "0" (the Idle state) may be 0 V to
2 V. If the power amplifier transistor is an N-channel depletion-mode GaAs MESFET, the
voltage signal corresponding to the voltage control signal "1" (the Busy state) may be -4 V
to 0 V. and the voltage signal corresponding to the voltage control signal "0" (the Idle state)
may be -5 V to -4 V. A port C51 of the power amplifier 520 is adapted to receive an RF
signal, a port C52 is adapted to connect a constant voltage Vdd of power source, and a port
C53 is adapted to output the RF signal.
The power amplifier 520 may be a Class A or Class AB amplifier, and the power
amplifier transistor 521 therein includes, but is not limited to, an LDMOS, a GaAs
MFSELI. a BJL a JEET, or a CAN transistor. The power amplifier 520 may also be an
integrated circuit, and the voltage control unit therein is implemented through a
digital-to-analog converter circuit or an analog switch circuit.
The voltage control unit is integrated in the power amplifier unit (which includes the
power amplifier). Thus, the universality of the power amplifier unit is improved.
Moreover, as the transmission path of the voltage signal is short, the interference to the
voltage signal caused by other signals is effectively prevented. Therefore, this
configuration is applicable when the main control unit is at a long distance to the power
amplifier.
The sytem for controlling power amplification is applicable to an RF transmitter,
and is also applicable to an NE such as a base station or a wireless terminal.
A system lor controlling power amplification is provided in a fifth embodiment of
the present invention, in which multiple power amplifiers are operated independently or
connected in parallel in operation. Referring to FIG. 10. the system includes a main
control unit 600. a voltage control unit 610, and a power amplifier unit formed by a first
power amplifier 620. a second power amplifier 630, and a third power amplifier 640.
A port A61 of the main control unit 600 is an information input port adapted to
obtain information related to an NE. The information includes at least one of signaling,
service information, external control signals, and internal clock signals of the NE. A
current state of the NE is determined according to the above information.
The NE may be in an Idle state or a Busy state. The Idle state indicates that the NE
is not required to output an RF signal, for example, the NE is not accessed by any
subscriber, in an idle timeslot, or receives a control signal for turning off the power
amplifier. The Busy state indicates that the NE is required to output an RF signal, for
example, the NE is accessed by subscribers, in a non-idle timeslot, or receives a control
signal lor turning on the power amplifier.
The main control unit 600 sends a voltage control signal according to the state of the
NE. For example, the voltage control signal corresponding to the Idle state is represented
by a logic voltage "0", and the voltage control signal corresponding to the Busy state is
represented by a logic voltage "1". Further, an inverse logic expression may also be
adopted, that is. the voltage control signal corresponding to the Idle state is represented by a
logic voltage " 1". and the voltage control signal corresponding to the Busy state is
represented by a logic voltage "0". The voltage control signal is output from a port A62.
When the power amplifier unit is formed by multiple power amplifiers, the main control
unit outputs multiple independent voltage control signals, and the logic expression of each
voltage control signal is the same as the preceding description. The main control unit 600
may be an integrated chip or a functional module of an integrated chip. The main control
unit may also be a part of a base station controller, and the voltage control signal is directly
sent to a transmitter on a base station side through a signaling channel by the base station
controller. The main control unit may also be directly integrated on a board of a
transmitter.
The voltage control unit 610 is connected to the main control unit 600, and adapted
to receive the voltage control signals from the main control unit 600 through a port B61,
obtain voltage signals according to the voltage control signals, and apply the obtained
voltage signals to grid electrodes of the power amplifier transistors 621, 631, and 641 or
base electrodes of the power amplifier transistors 621. 631. and 641 through a port B62,
respectively. Here, the port B62 can output three independent voltage signals to control
the three power amplifiers independently, or output only one voltage signal to control the
three power amplifiers uniformly. The value of the voltage signals varies for different
power amplifier transistors. For example, when the power amplifier transistors are
N-channel LDMOSs. the voltage signals corresponding to the voltage control signals "1"
(the Busy state) may be 2 V to 5 V. and the voltage signals corresponding to the voltage
control signals '0" (the Idle state) may be 0 V to 2 V. If the power amplifier transistors are
N-channel depletion-mode GaAs MESFETs. the voltage signals corresponding to the
voltage control signals "1" (the Busy state) may be -4 V to 0 V, and the voltage signals
corresponding to the voltage control signals "0" (the Idle slate) may be -5 V to -4 V. The
voltage control Link may be formed by an analog switch circuit or a digital-to-analog
convener circuit. The voltage control unit may be set separately or integrated in the main
control unit or the power amplifier unit as a functional module.
When the fust power amplifier 620, the second power amplifier 630, and the third
power amplifier 640 operate independently, ports C61, C64, and C67 receive three
independent RF signals, and ports C63, C66. and C69 output three amplified RF signals,
respectively. Each of the power amplifiers is adapted to switch on or switch off according
to the voltage signal applied to the grid electrode or the base electrode of the power
amplifier transfer therein. The first power amplifier 620. the second power amplifier 630,
and the third power amplifier 040 may respectively include one or more power amplifier
transistors, and ports C62, C65. and C68 thereof are connected to a constant power supply
voltage Vdd respectively.
When the power amplifiers operate in parallel, the ports C61 ,C64, and C67 receive
one RF signal, which is then divided into three signals. The three signals are amplified by
the three power amplifiers, then combined by the ports C63, C66, and C69, and output as
one RF signal. Each of the power amplifiers is adapted to switch on or switch off
according to a bias voltage signal applied to the grid electrode or the base electrode of the
power amplifier transistor therein. The first power amplifier 620, the second power
amplifier 630. and the third power amplifier 640 may respectively include one or more
power amplifier transistors, and the ports C62, C65, and C68 thereof are connected to a
constant voltage Vdd of a power source respectively. The main control unit controls, via
the voltage signal, the number of the power amplifiers which are in the On state, according
to the input RF power, so as to improve the overall efficiency of the power amplifier unit.
For example, only one power amplifier switches on when the power of the input RF signal
is small, and three power amplifiers are turned on when the power of the input RF signal is
large. The three power amplifiers may be controlled uniformly by one voltage signal, so
as to double the output power.
The first power amplifier 620, the second power amplifier 630, and the third power
amplifier 640 may be Class A or Class AB amplifiers, and the power amplifier transistors
therein include, but are not limited to, LDMOS, GaAs MESFET, BJT, JFET, or GAN
transistors.
The main control unit outputs multiple voltage signals through the voltage control
unit, which realizes the collective control over multiple power amplifiers, saves the
equipment cost, and improves the efficiency of the power amplifiers.
The system for controlling power amplification is applicable to an RF transmitter,
and is also applicable to an NE such as a base station or a wireless terminal.
Sometimes, multiple power amplifiers need to be connected in series in operation to
obtain a higher gain. A system for controlling power amplification is provided in a sixth
embodiment of the present invention, in which power amplifiers are connected in series in
operation. Referring to FIG. 11, the system includes a main control unit 700. a voltage
control unit 710, and a power amplifier unit formed by a first power amplifier 720, a second
power amplifier 730, and a third power amplifier 740.
A port A71 of the main control unit 700 is an information input port adapted to
obtain information related to an NE. The information includes at least one of signaling,
service information, external control signals, and internal clock signals of the NE. A
current state of the NE is determined according to the above information.
The NE may be in an Idle state or a Busy state. The Idle state indicates that the NE
is not required to output an RF signal, for example, the NE is not accessed by any
subscriber, in an idle timeslot. or receives a control signal for turning off the power
amplifier. The Busy state indicates that the NE is required to output an RF signal, for
example, the NE is accessed by subscribers, in a non-idle timeslot, or receives a control
signal for turning on the power amplifier.
The main control unit 700 sends a voltage control signal according to the state of the
NE. For example, the voltage control signal corresponding to the Idle state is represented
by a logic voltage "0". and the voltage control signal corresponding to the Busy state is
represented by a logic voltage "1". Further, an inverse logic expression may also be
adopted, that is. the voltage control signal corresponding to the Idle state is represented by a
logic voltage "1". and the voltage control signal corresponding to the Busy state is
represented by a logic voltage '"0". The voltage control signal is output from a port A72.
If the power amplifier unit is formed by multiple power amplifiers, the main control unit
outputs multiple independent voltage control signals, and the logic expression of each
voltage control signal is the same as the preceding description. The main control unit 700
may be an integrated chip or a functional module of an integrated chip. The main control
unit may also be a part of a base station controller, and the voltage control signal is directly
sent to a transmitter on a base station side through a signaling channel by the base station
controller. The main control unit may also be directly integrated on a board of a
transmitter.
The voltage control unit 710 is connected to the main control unit 700, and adapted
to receive the voltage control signals from the main control unit 700 through a port B71,
obtain voltage signals according to the voltage control signals, and apply the obtained
voltage signals to grid electrodes of the power amplifier transistors 721, 731, and 741 or
base electrodes of the power amplifier transistors 721, 731, and 741 through a port B72,
respectively. Here, the port B72 can output three independent voltage signals to control
the three power amplifiers independently, or output only one voltage signal to control the
three power amplifiers uniformly. In addition, for the power amplifiers connected in series,
the voltage signal may be applied to individual power amplifiers. For example, in this
embodiment, the voltage signal is applied to only the grid electrode of the power amplifier
transistor 741 in the last power amplifier 740. The value of the voltage signal varies for
different power amplifier transistors. For example. If the power amplifier transistors are
N-channel LDMOSs. the voltage signals corresponding to the voltage control signals "1"
(the Busy state) may be 2 V to 5 V. and the voltage signals corresponding to the voltage
control signals "0" (the Idle state) may be 0 V to 2 V. When the power amplifier
transistors are N-channel depletion-mode GaAs MESFETs, the voltage signals
corresponding to the voltage control signals "'1" (the Busy state) may be -4 V to 0 V, and the
voltage signals corresponding to the voltage control signals "0" (the Idle state) may be -5 V
to -4 V. The voltage control unit may be formed by an analog switch circuit or a
digital-to-analog converter circuit. The voltage control unit may be set separately or
integrated in the main control unit or the power amplifier unit as a functional module.
The first power amplifier 720. the second power amplifier 730, and the third power
amplifier 740 arc connected in series in operation, and each of the power amplifiers switch
on or switch off according to a bias voltage signal applied to the grid electrode or the base
electrode of the power amplifier transistor therein. The first power amplifier 720, the
second power amplifier 730, and the third power amplifier 740 may respectively include
one or more power amplifier transistors. A port C71 is an RF signal input terminal, ports
C73 and C74 arc connected, ports C76 and C77 are connected such that the RF signals are
amplified on three stages and output from a port C79, and ports C72, C75. and C78 are
connected to a constant voltage Vdd ol a power supply respectively.
The first power amplifier 720, the second power amplifier 730, and the third power
amplifier 740 may be Class A or Class AB amplifiers, and the power amplifier transistors
therein include, but are not limited to, LDMOS, GaAs MESFET, BJT, JFET. or GAN
transistors.
The system for controlling power amplification is applicable to an RF transmitter,
and is also applicable to an NE such as a base station or a wireless terminal.
A device for controlling power amplification is provided in a seventh embodiment
of the present invention. The device includes a main control unit and a voltage control
unit. The mail, control unit is adapted to obtain the state of an NE, and send a voltage
control signal according to the state. The voltage control unit is adapted to output a
voltage signal to a grid electrode or a base electrode of a power amplifier transistor in a
power amplifier unit according to the voltage control signal.
The main control unit further includes an information acquisition module, a state
acquisition module, and a signal sending module.
The information acquisition module is adapted to acquire information related to the
equipment. The information is signaling, service information, control signals, or internal
clock signals.
The state acquisition module is adapted to acquire the state of the equipment
according to the above information.
The signal sending module is adapted to send the voltage signal according to the
state of the equipment.
Though several specific embodiments of the present invention are disclosed above,
the present invention is not limited thereto. Various modifications and variations that can
be thought of by persons skilled in the art shall fall within the protective scope of the
present invention.
WE CLAIM:
1. A method for controlling power amplification, comprising:
outputting a voltage signal according to the state of a network equipment, NE; and
applying the voltage signal to a grid electrode or a base electrode of at least one power
amplifier transistor in a power amplifier.
2. The method of claim 1, further comprising:
obtaining information related to the NE, wherein the information includes at least one
of signaling, service information, external control signal, internal clock signal; and
determining the state of the NE according to the information.
3. The method of claim 2, wherein outputting a voltage signal according to the state of
an NE comprises:
outputting a first voltage signal according to the state of the NE if the state of the NE is
Busy; or
outputting a second voltage signal according to the state of the NE if the state of the NE
is Idle.
4. The method of claim 3, wherein:
the Idle state indicates that the NE is not required to output a radio frequency signal;
and
the Buss stale indicates that the NE is required to output a radio frequency signal.
5. The method of claim 1, wherein applying the voltage signal to a grid electrode or a
base electrode of at least one power amplifier transistor in a power amplifier is in order to
enable the power amplifier transistor to switch on or switch off according to the voltage
signal.
6. A transmitter, comprising:
a main control unit, adapted to obtain a state of a network equipment, NE, where the
transmitter is located, and send a voltage control signal according to the state;
a voltage control unit, adapted to output a voltage signal according to the voltage
control signal received from the main control unit; and
a power amplifier unit, adapted to switch on or switch off according to the voltage
signal applied to a grid electrode or a base electrode of at least one power amplifier
transistor therein by the voltage control unit.
7. The transmitter of claim 6. wherein the main control unit comprises:
an information acquisition module, adapted to acquire information related to the NE, the
information includes at least one of signaling, service information, external control signals,
internal clock signals of the NE:
a state acquisition module, adapted to determine the state of the NE according to the
above information: and
a signal sending module, adapted to send the voltage signal according to the state of the
NE.
8. A network equipment. NE, for controlling power amplification, comprising:
a main control unit, adapted to obtain a state of the NE, and send a voltage control
signal according to the state;
a voltage control unit, adapted to output a voltage signal according to the voltage
control signal received from the main control unit; and
a power amplifier unit, adapted to switch on or switch off according to the voltage
signal applied to a grid electrode or a base electrode of at least one power amplifier
transistor in the power amplifier unit.
9. The NE of claim 8. wherein the main control unit comprises:
an information acquisition module, adapted to acquire information related to the NE, the
information includes at least one of signaling, service information, external control signals,
internal clock signals;
a slate acquisition module, adapted to determine the state of the NE according to the
information: and
a signal sending module, adapted to send the voltage control signal according to the
state of the NE.
10. The NE of claim 8. wherein the power amplifier unit comprises at least two power
amplifier, wherein the at least two power amplifier are connected in parallel or in series or
operated independently.
11. The NE of claim 8. wherein the NE is a base station or a terminal.

A method and an NE for controlling power amplification are provided. The method
for controlling power amplification includes: outputting a voltage signal according to the
state of an NE: applying the voltage signal to a grid electrode or a base electrode of at least
one power amplifier transistor in a power amplifier. Thus, static power dissipation of the
power amplifier tan be eliminated when no RE power is output, and the efficiency of the
power amplifier can be improved by using the above method and NE.

Documents:

http://ipindiaonline.gov.in/patentsearch/GrantedSearch/viewdoc.aspx?id=zblAIMWVESa+wUmyhFp73A==&loc=wDBSZCsAt7zoiVrqcFJsRw==

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Patent Number

272143

Indian Patent Application Number

10/KOLNP/2010

PG Journal Number

13/2016

Publication Date

25-Mar-2016

Grant Date

18-Mar-2016

Date of Filing

01-Jan-2010

Name of Patentee

HUAWEI TECHNOLOGIES CO., LTD.

Applicant Address

HUAWEI ADMINISTRATION BUILDING, BANTIAN, LONGGANG DISTRICT, SHENZHEN, GUANGDONG 518129, P.R. CHINA

Inventors:

#	Inventor's Name	Inventor's Address
1	YIN, WEIMIN	HUAWEI ADMINISTRATION BUILDING, BANTIAN, LONGGANG DISTRICT, SHENZHEN, 518129, GUANGDONG, P.R. CHINA
2	ZHANG, XIKUN	HUAWEI ADMINISTRATION BUILDING, BANTIAN, LONGGANG DISTRICT, SHENZHEN, 518129, GUANGDONG, P.R. CHINA
3	SUN, JIE	HUAWEI ADMINISTRATION BUILDING, BANTIAN, LONGGANG DISTRICT, SHENZHEN, 518129, GUANGDONG, P.R. CHINA
4	CHEN, WEI	HUAWEI ADMINISTRATION BUILDING, BANTIAN, LONGGANG DISTRICT, SHENZHEN, 518129, GUANGDONG, P.R. CHINA
5	SUN, YIPING	HUAWEI ADMINISTRATION BUILDING, BANTIAN, LONGGANG DISTRICT, SHENZHEN, 518129, GUANGDONG, P.R. CHINA
6	SUN, YIJUN	HUAWEI ADMINISTRATION BUILDING, BANTIAN, LONGGANG DISTRICT, SHENZHEN, 518129, GUANGDONG, P.R. CHINA

PCT International Classification Number

H04B1/04; H04B7/005; H04B1/04

PCT International Application Number

PCT/CN2008/071966

PCT International Filing date

2008-08-13

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1	200710076519.8	2007-08-17	China