Title of Invention

A CLOSED LOOP POWER CONTROL METHOD OF REVERSE SUPPLEMENT CHANNEL

Abstract

A closed loop power control method of reverse supplement channel includes accounting the frame quality combination condition of reverse supplement channel R-SCH and reverse primary channel R-FCH calculating the power bias's adjustment amount GR.SCH according to the said statistical result to adjust R-SCH power. Utilizing the said method of the present invention can ensure R-FCH error rate converges to the goal error rate, meanwhile achieve independence closed loop power control to R-SCH make R-SCH bit error converge to goal error rate commendably.

Full Text

A CLOSED LOOP POWER CONTROL METHOD OF REVERSE SUPPLEMENT CHANNEL Field of the Invention [001] The present invention relates to the field of wireless communications, and in particular, to a method for closed loop power control of a Reverse Supplement Channel (R-SCH). Background of the Invention [002] Wireless communications will play an increasingly important role in future communication systems. Code Division Multiple Access (CDMA) will become one of the main wireless access techniques for the 3rd generation (3G) mobile communication systems. IS2000 is one of the standards for 3G mobile communication systems. [003] In Reverse Closed Loop Power Control (RCLPC) of a reverse service channel in a 3G mobile communication system employing IS2000 standard, the power of the reverse service channel is controlled by a Reverse Pilot (R-PILOT) Channel. A Base Station Controller (BSC) adjusts the power of the R-PILOT Channel at a rate of 800Hz by using reverse power control bits. The relatively fixed power offset of a Reverse Fundamental Channel (R-FCH) and a Reverse Supplement Channel (R-SCH) from the R-PILOT Channel, as shown in Figure 1, causes the power of the R-FCH and the R-SCH to change with the change in the power of the R-PILOT Channel. [004] The RCLPC is configured to maximize the reverse capacity of one or more service channels while keeping the Frame Error Rates (FER) of the service channels low. If only one service channel, such as an R-FCH is activated, the RCLPC is achieved in such a way that a BSC adjusts the power of the R-FCH by adjusting the power of an R-PILOT Channel according to the quality of the frames received from the R-FCH. However, it is difficult to achieve the RCLPC if multiple service channels, such as an R-FCH and an R-SCH are activated. In this case, the RCLPC should be able to control the power of the R-FCH according to the R-FCH frame quality while controlling the power of the R-SCH independently according to the R-SCH frame quality. In addition, base station CSM5000 chips sometimes may not be able to distinguish erroneous SCH frames from Discontinuous Transmission (DTX) SCH frames, which also brings difficulty to realize the function of RCLPC. [005] Figure 2 schematically illustrates one method for reverse closed loop power control of an R-SCH according to the prior art. [006] The closed loop power control of an R-FCH and an R-SCH are combined together by the method illustrated in Figure 2. In the power control outer loop of a BSC, an RCLPC algorithm generates a value for the outer loop by considering both the R-FCH frame quality and the R-SCH frame quality, and simultaneously controls both the power of the R-FCH and the power of the R-SCH, by adjusting the power of the R-PILOT Channel using reverse power control bits via a controlling channel according to the value for the outer loop. [007] According to the method illustrated in Figure 2, the power offset of the R-SCH and of the R-FCH from the R-PILOT Channel is fixed, and the difference between the power of the R-SCH and the R-FCH is kept constant. Therefore, it may not be possible to perform the closed loop power control on the R-SCH and the R-FCH independently. If there is a difference between the wireless characteristics of these two service channels, it may not be possible to adjust their power differently. Moreover, it may not be possible for the frame error rate of both the R-SCH and the R-FCH to converge on a target frame error rate. [008] Figure 3 schematically illustrates another method for RCLPC of an R-SCH according to the prior art. [009] The method illustrated in Figure 3 includes: indirectly adjusting the power of an R-FCH and an R-SCH by controlling an R-PILOT Channel by using power control bits according to the R-FCH frame quality; and adjusting the power of an R-SCH by changing the power offset GR.SCH of the R-SCH from the R-PILOT Channel through a Layer 3 message according to the R-SCH frame quality. [0010] According to the method illustrated in Figure 3, two different power control operations, which are combined together without any coordination there between, are performed on the power of R-SCH. Therefore, it may not be ensured that the frame error rate of the R-SCH converges on a target frame error rate. Summary of the Invention [0011] An object of the present invention is to provide a method for closed loop power control of an R-SCH while ensuring the convergence of the frame error rate of the R-FCH to a target frame error rate. [0012] An embodiment of the invention provides a method for closed loop power control of an R-SCH, and the method includes: [0013] making statistics of each of the combinations of R-SCH frame quality and R-FCH frame quality; [0014] calculating a adjustment value for power offset GR.SCH according to the counting result, and adjusting the power of the R-SCH in which the power offset GR.SCH is the power difference between the R-SCH and an R-PILOT Channel. [0015] Preferably, the R-SCH frame quality and the R-FCH frame quality are combined, and the frame number in each of the combinations is counted. [0016] Preferably, the R-SCH frame quality and the DTX R-SCH frame quality are combined, and the frame number in each of the combinations is counted. [0017] The method further includes counting the DTX frames as bad R-SCH frames. [0018] The making statistics of each of the combinations of the R-SCH frame quality and the R-FCH frame quality includes the following: [0019] creating an inspection window; [0020] counting the frame number in each of the combinations in the inspection window; and [0021] calculating the frame error rate of the R-SCH frames in the inspection window. [0022] The method further includes: [0023] calculating an adjustment value for the GR.SCH in each of the combinations according to the counting result; and [0024] obtaining a final adjustment value for the GR.SCH according to the calculated adjustment value for the GR.SCH in each of the combinations. [0025] Preferably, the adjustment value for the GR.SCH is calculated by using a fixed cycle or a variable cycle. [0026] The method further includes: [0027] transmitting, by a base station, the adjustment value for the GR.SCH to a mobile station through an air interface message; and [0028] adjusting, by a base station, the GR.SCH according to the received adjustment value for the GR.SCH, and adjusting the power of the R-SCH. [0029] Preferably, the GR.SCH is adjusted by means of a reverse channel power adjustment factor, and the power of the R-SCH is thus adjusted. [0030] In summary, according to an embodiment of the invention, an adjustment value for GR.SCH is calculated by making statistics of each of the combinations of the R-SCH frame quality and the R-FCH frame quality, so that the power of the R-SCH may be adjusted independently and it may be ensured that the adjustment on the power of the R-SCH is not coupled with the adjustment on the power of the R-FCH. Therefore, the closed loop power control of the R-SCH may be performed independently, and it may be ensured that the frame error rate of the R-FCH is converged on a target frame error rate. According to an embodiment of the invention, the influence of a base station's erroneous judgment of the R-SCH frame quality on the power control may be reduced by differently processing R-SCH DTX. Brief Description of the Drawings [0031] Figure 1 schematically illustrates power relations between an R-FCH, an R-SCH and an R-PILOT Channel; [0032] Figure 2 schematically illustrates one method for RCLPC of an R-SCH in the prior art; [0033] Figure 3 schematically illustrates another method for RCLPC of an R-SCH in the prior art; [0034] Figure 4 schematically illustrates a method for closed loop power control of an R-SCH according to an embodiment of the invention; and [0035] Figure 5 is an exemplary flow chart of a method for closed loop power control of an R-SCH according to an embodiment of the invention. Detailed Description of the Embodiments [0036] An embodiment of the invention provides a method for closed loop power control of an R-SCH, in which an adjustment value for GR.SCH is calculated by making statistics of each of the combinations of the R-SCH frame quality and the R-FCH frame quality, so that the power of the R-SCH may be adjusted independently. [0037] The principles, characteristics and advantages of the invention will become more apparent under the detailed descriptions of the invention with reference to the drawings and specific examples. Figure 4 schematically illustrates an embodiment of a method for closed loop power control of an R-SCH according to an embodiment of the invention. [0038] The closed loop power control of the R-SCH is supplement to the closed loop power control of the R-FCH. The closed loop power control of the R-FCH implements high-frequency and precise control of the R-FCH and the R-SCH, and the closed loop power control of the R-SCH implements separate supplement control of the R-SCH. [0039] If the frame error rate of the R-FCH has achieved FER convergence, and the R-SCH has not achieved FER convergence according to the R-FCH frame quality and the R-SCH frame quality, a formula for calculating the adjustment value for the GR.SCH (shown in detail below) may be deduced by establishing a mathematical model according to an algorithm for the closed loop power control of the R-SCH, and the adjustment value for the GR.SCH may be determined. The GR-SCH may then be adjusted according to the adjustment value for the GR.SCH, so that the R-SCH converges on the target FER. [0040] If the R-FCH does not converge on the target FER, it is indicated that the power of the R-PILOT Channel is improper and needs to be adjusted. As a result, there is no an adjustment reference for the closed loop power control of the R-SCH. In this case, the power offset GR.SCH cannot be adjusted and the closed loop power control of the R-SCH cannot be performed; otherwise, the power of the R-SCH will be readjusted and coupled with the power adjustment of the R-FCH. [0041] For example, figure 5 shows an exemplary flow chart of the method for closed loop power control of an R-SCH according to an embodiment of the invention. [0042] In block 5-1, an inspection window is created in a reverse service channel. [0043] For example, an inspection window, whose size may be preset to e.g. W frames according to actual requirements, is created in a reverse service channel. [0044] In block 5-2, the frame number in each of the combinations of R-SCH frame quality and R-FCH frame quality are counted by the inspection window. [0045] For example, when closed loop power control needs to be performed on the R-SCH, the frame number in each of the combinations of R-SCH frame quality and R-FCH frame quality are counted by the inspection window. In an embodiment, each of the R-FCH frames and the R-SCH frames is counted as either a good frame or a bad frame, and thus four combinations are obtained. By analyzing the four combinations, it is determined whether the GR.SCH needs to be increased, decreased or kept unchanged. [0046] The relationships between the combinations of R-SCH frame quality and R-FCH frame quality and correspondent adjustments of the GR.SCH are shown in Table 1. Table 1 (Table Removed) [0047] In an embodiment, the frame number in each of the four combinations shown in Table 1, i.e. combination A, B, C and D, are counted. [0048] For example, in an inspection window having a size of W frames, if the frame number in combination A is a, the frame number in combination B is b, the frame number in combination C is c, and the frame number in combination D is d, [0049] then a + b + c + d = W. [0050] In block 5-3, the adjustment value for the GR-SCH is calculated according to the counting result. [0051] Assuming that the frame error rate of the R-SCH and the R-FCH within the inspection window have achieved FER convergence, then: a + b + c + d D W; (b + c) / W = FER_SCH (frame error rate of the R-SCH frames); and (d + c) / W = FER_FCH (frame error rate of the R-FCH frames). [0052] An increasing step size and a decreasing step size of the adjustment value for the GR.SCH may be deduced according to the above equations. [0053] When the inspection window is closed, the adjustment value for the GR.SCH may be calculated according to the relationships between the frame number in the four combinations A, B, C and D. Moreover, the adjustment value for the GR.SCH may vary between a maximum value and a minimum value. [0054] In another embodiment, in addition to the four combinations shown in Table 1, the two combinations of the R-SCH frame quality and the R-SCH DTX quality may be considered. [0055] In order to reduce the influence of a base station's erroneous judgment of the R-SCH frame quality on the power control, a DTX frame is regarded as an erroneous SCH frame that is erroneously judged as a DTX frame, and the DTX frame is counted as a bad R-SCH frame. [0056] According to an embodiment of the invention, in addition to using a fixed cycle, the adjustment value for the GR-SCH may be calculated by using a variable cycle. [0057] In block 5-4, the calculated adjustment value for the GR.SCH is transmitted to a mobile station through an air interface message. [0058] According to an embodiment of the invention, after the adjustment value for the GR.SCH is calculated, a separate control channel is provided for the closed loop power control of the R-SCH, and the calculated adjustment value for the GR.SCH is transmitted to the mobile station by transmitting an air interface message via the separate control channel. [0059] In block 5-5, the mobile station adjusts the power of the R-SCH according to the adjustment value for the GR-SCH. [0060] The mobile station adjusts the power offset GR.SCH between the R-SCH and the R-PILOT Channel according to the received adjustment value for the GR-SCH. The GR.SCH may be adjusted by means of a reverse channel adjustment factor (Reverse_Channel_Adjustment_Gain). The power of the R-SCH may be adjusted by adjusting the GR.SCH, so that the frame error rate of the R-SCH may converge on a target frame error rate. [0061] Additional advantages and modifications will readily occur to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details and representative embodiments shown and described herein. Accordingly, various modifications and variations may be made without departing from the spirit or scope of the invention as defined by the appended claims and their equivalents. CLAIMS What is claimed is: 1. A method for closed loop power control of a Reverse Supplement Channel (R-SCH), comprising: making statistics of each of the combinations of R-SCH frame quality and Reverse Fundamental Channel (R-FCH) frame quality; calculating an adjustment value for power offset GR.SCH according to the counting result; and adjusting the power of the R-SCH according to the adjustment value for the power offset GR.SCH- 2. The method according to claim 1, wherein the power offset GR.SCH is the power difference between the R-SCH and a Reverse Pilot (R-PILOT) Channel. 3. The method according to claim 1, further comprising: combining the R-SCH frame quality and the R-FCH frame quality; and counting the frame number in each of the combinations. 4. The method according to claim 2, further comprising: combining the R-SCH frame quality and the Discontinuous Transmission (DTX) R-SCH frame quality; and counting the frame number in each of the combinations. 5. The method according to claim 3, further comprising: counting the DTX frames as bad R-SCH frames. 6. The method according to claim 1, 2 or 3, wherein the making statistics of each of the combinations of the R-SCH frame quality and the R-FCH frame quality comprises: creating an inspection window; counting the frame number in each of the combinations in the inspection window; and calculating the frame error rate of the R-SCH frames in the inspection window according to the frame number in each of the combinations. 7. The method according to claim 6, further comprising: calculating an adjustment value for the GR.SCH in each of the combinations according to the counting result; and obtaining a final adjustment value for the GR.SCH according to the calculated adjustment value for the GR.SCH in each of the combinations. 8. The method according to claim 6 or 7, wherein the adjustment value for the GR.SCH is calculated by using a fixed cycle or a variable cycle. 9. The method according to claim 6, further comprising: transmitting, by a base station, the adjustment value for the GR.SCH to a mobile station through an air interface message; and adjusting the power of the R-SCH by adjusting, by the mobile station, the GR.SCH according to the received adjustment value for the GR.SCH- 10. The method according to claim 6 or 9, wherein the power of the R-SCH is adjusted by adjusting the GR.SCH by means of a reverse channel power adjustment factor.

Documents:

460-delnp-2008-1-Claims-(31-07-2013).pdf

460-delnp-2008-1-Correspondence Others-(31-07-2013).pdf

460-delnp-2008-1-GPA-(31-07-2013).pdf

460-delnp-2008-abstract.pdf

460-delnp-2008-Claims Copy-(20-10-14}.pdf

460-delnp-2008-Claims-(20-10-14}.pdf

460-delnp-2008-claims.pdf

460-delnp-2008-Coprrespondence Others-(18-03-2014).pdf

460-delnp-2008-Correspondance-(20-10-14}.pdf

460-delnp-2008-Correspondence Others-(16-02-2012).pdf

460-delnp-2008-Correspondence Others-(18-01-2013).pdf

460-delnp-2008-Correspondence Others-(19-09-2013).pdf

460-delnp-2008-Correspondence Others-(20-06-2011).pdf

460-delnp-2008-Correspondence Others-(22-05-2013).pdf

460-delnp-2008-Correspondence Others-(31-07-2013).pdf

460-delnp-2008-Correspondence-others (21-03-2014).pdf

460-delnp-2008-correspondence-others.pdf

460-delnp-2008-description (complete).pdf

460-delnp-2008-drawings.pdf

460-delnp-2008-form-1.pdf

460-delnp-2008-Form-13-(27-03-2008).pdf

460-delnp-2008-form-2.pdf

460-delnp-2008-Form-3-(19-09-2013).pdf

460-delnp-2008-Form-3-(20-06-2011).pdf

460-delnp-2008-form-3.pdf

460-delnp-2008-form-5.pdf

460-delnp-2008-GPA-(20-10-14}.pdf

460-delnp-2008-GPA-(22-05-2013).pdf

460-delnp-2008-pct-210.pdf

460-delnp-2008-pct-237.pdf

460-delnp-2008-pct-304.pdf

460-delnp-2008-pct-373.pdf

460-delnp-2008-Petition-137-(31-07-2013).pdf

Cover letter with Form 3.pdf

Petition under Rule 137.pdf