Title of Invention

METHOD AND APPARATUS FOR DETERMINING ABORTION OF RECEPTION OF MESSAGE IN A CDMA COMMUNICATION SYSTEM

Abstract

Whether to abort reception of a multi-part message in a code division multiple access communication system is determined by receiving a part of the multi-part message. Correlating the received part of the multi-part message with a known sequence generates a correlation value. The correlation value is compared with a threshold level. Reception of the multi-part message is aborted if the correlation value is less than a threshold level. In another aspect, the threshold level is dynamically adjusted based on a communication traffic behavior. The communication traffic behavior may be, for example, whether traffic directed to a particular user equipment (UE) is part of a burst directed to that UE.

Full Text

FORM2 THE PATENTS ACT, 1970 (39 of 1970) & THE PATENTS RULES, 2003 COMPLETE SPECIFICATION (See section 10, rule 13) "ADAPTIVE THRESHOLD FOR HS-SCCH PART 1 DECODING" TELEFONAKTIEBOLAGET LM ERICSSON (PUBL), a Swedish company of 164 83 Stockholm, Sweden. The following specification particularly describes the invention and the manner in which it is to be performed. WO 2005/041465 PCT/EP2004/011147 2_ ADAPTIVE THRESHOLD FOR HS-SCCH PART 1 DECODING 5 BACKGROUND The present invention relates to communications systems, more particularly to Code Division Multiple Access (CDMA) communications systems, and even more particularly to efficiently and accurately determining whether particular information has been detected in a received signal in a CDMA communications 10 system. The cellular telephone industry has made phenomenal strides in commercial operations throughout the world. Growth in major metropolitan areas has far exceeded initial expectations and is rapidly outstripping system capacity. If this trend continues, the effects of this industry's growth will soon reach even fee 15 smallest markets. Innovative solutions are required to meet these increasing capacity needs as well as to maintain high quality service and avoid rising prices. Throughout the world, one important step in the advancement of radio communication systems has been the change from analog to digital transmission. Equally significant is the choice of an effective digital transmission scheme for 20 implementing next generation technology. Furthermore, Personal Communication Networks (PCNs), employing low cost, pocket-sized, cordless telephones that can be carried comfortably and used to make or receive calls in the home, office, street, car, and the like, are being provided by, for example, cellular carriers using the digital cellular system infrastructure. An important feature desired in these new systems is 25 increased traffic capacity, arid efficient use of this capacity. It is also important for the portable devices in such systems to provide high quality service while conserving energy to whatever extent possible, since they are very often powered by batteries. WO 2005/041465 3, PCT/EP2004/011147 Recent efforts at providing such systems have focused on the use of Wideband CDMA (WCDMA) techniques. In a WCDMA system, multiple users utilize the same radio spectrum simultaneously. From the point of view of a receiver in a WCDMA system, a received signal comprises a desired signal (i.e., a signal 5 intended to be received by that particular receiver) and a high level of noise. To enable the receiver to extract the desired signal from the received signal, information intended for that receiver is "spread" by combining (e.g., by multiplying) the information with a much higher bit rate known signature sequence. The signature sequence is unique to this particular receiver. One way to generate the signature 10 sequence is with a pseudo-noise (PN) process that appears random, but can be replicated by an authorized user. Because each active transmitter is utilizing the same process, a plurality of spread information signals modulate a radio frequency carrier, for example by binary phase shift keying (BPSK), and as said before, are jointly received as a 15 composite signal at the receiver. Each of the spread signals overlaps all of the other spread signals, as well as noise-related signals, in both frequency and time. If me receiver is authorized, then the composite signal is correlated with one of the unique signature sequences, and the corresponding information signal can be isolated and despread. If quadrature phase shift keying (QPSK) modulation or quadrature 20 amplitude modulation (QAM) is used, then the signature sequence may consist of complex numbers (having real and imaginary parts), where the real and imaginary parts are used to modulate respective ones of two carriers at the same frequency, but ninety degrees out of phase with respect to one another. Traditionally, a signature sequence is used to represent one bit of 25 information. However, other types of signature sequences can he employed. Receiving the transmitted signature sequence or its complement indicates whether the information bit is a +1 or -1 sometimes denoted "0" or '1' The signature sequence usually comprises some number, N, bits, and each bit of the signature sequence is called a "chip". The entire N-chip sequence, or its complement, is 30 referred to as a transmitted symbol. The conventional receiver, such as a RAKE receiver, correlates the received signal with the complex conjugate of the known signature sequence to produce a correlation value. Only the real part of the WO 2005/041465 PCT/EP2004/011147 4 correlation value is computed. When a large positive correlation results, a "0" is detected; when a large negative correlation results, a "1" is detected. It should be recognized that other types of receivers and other correlation techniques can be employed, 5 A number of efforts to standardize the use of WCDMA techniques in mobile communication systems exist One such effort is being accomplished by the Third Generation Partnership Project ("3GPP"). The term "third generation Refers to the fact that so-called second-generation radio access technology brought mobile telephony to a broad market By contrast, third-generation radio access technology 10 extends beyond basic telephony: a common, Internet Protocol (IP)-based service platform will offer mobile users an abundance of real-time and non-real time (traditional data) services. Typical services with real-time requirements are voice and video, as well as delay-sensitive applications, such as traffic-signaling systems, remote sensing, and 15 systems that provide interactive access to World Wide Web (WWW) servers. As explained in, for example, F. Miller et al, "Further evolution of me GSM/EDGE xadio access network", Ericsson Review vol. 78, no. 3, pp. 116-123 (2001), the challenge is to implement end-to-end services based on the Internet Protocol (IP). The main benefit of running IP end-to-end —including over the air interface—is 20 service flexibility. Indeed, flexibility more or less eliminates dependencies between applications and underlying networks, for example, access networks. To date, cellular access networks have been optimized in terms of voice quality and spectrum efficiency for circuit-switched voice applications. However, for services such as IP multimedia, which includes voice, the main challenge is to retain comparable quality 25 and spectrum efficiency without decreasing service flexibility. Today, for example, we can suffer considerable protocol overhead when we bridge the air interface with real-time protocol (RTP) use rdatagram protocol (UDP) or fP packets (which carry media frames). Needless to say, this runs counter to the goal of spectrum efficiency. To achieve spectrum efficiency, we can instead characterize different packet data 30 streams in terms of bandwidth and delay requirements. Characterization of this kind; is useful when implementing admission access algorithms that accommodate multiple user data streams in available spectrum. Different methods of limiting data WO 2005/041465 PCT/EP2004/011147 5 (such as header compression and session signaling compression) must also be applied to obtain adequate spectrum efficiency. T. Hedberg and S. Parfcvall, "Evolving WCDMA", Ericsson Review vol. 77, no. 2 pp. 124-131 (2001) describes how, for the purpose of improving support for 5 best-effort packet data, the 3GPP is working on an evolution of WCDMA known as high speed downlink packet data access (HSDPA). This enhancement to prior systems increases capacity, reduces round-trip delay, and increases peak data rates up to 8-10 Mbit/s. To achieve these goals, a new downlink shared channel (HS-DSCH) has been introduced. In addition, three fundamental technologies, which are 10 tightly coupled and rely on the rapid adaptation of me transmission parameters to the instantaneous radio conditions, have been introduced with this channel: fast-link adaptation technology allows adaptation of the channel coding rate, and enables the use of spectral-efficient higher-order modulation (e.g., 16 QAM) when channel conditions permit (for example, during a fading peak), and reverts to 15 robust QPSK modulation during less favorable channel conditions (for example, when experiencing a fading dip); fast hybrid automatic-repeat-request (H-ARQ) technology rapidly requests the retransmission of missing data entities and combines the soft information from the original transmission and any subsequent retransmissions before any attempts 20 are made to decode a message; and fast scheduling of users sharing me HS-DSCH - this technique, which exploits multi-user diversity, strives to transmit to users with favorable radio conditions. With the basic principles above, there is a possibility of unequal service 25 provision, offering higher data rates to users in favorable conditions. One aspect of HSDPA is its channel structure. The transport channel for tarrying user dataris a-high=speed downlink shared channel (HS=DSCH), A corresponding physical channel is denoted by HS-PDSCH. The HS-DSCH code resources include one or more channelization codes with a fixed spreading factor of 30 16. In order to leave sufficient room for other required control and data bearers, up to 15 such codes can be allocated. The available code resources .are primarily shared in me time domain. For example, they may be allocated to one user at a time. WO 2005/041465 PCT/EP2004/011147 6 Alternatively, the code resources may be shared using code multiplexing. In this case, two to four users share the code resources within a same transmission time interval (TTI). The HS-DSCH employs a short (2ms) TTI in order to reduce link adaptation 5 delays, increase the granularity in the scheduling process, facilitate better tracking of the time varying radio conditions, and decrease the round trip time (RTF). La addition to user data, it is also necessary to transmit control signaling to notify the next user equipment (UE) to be scheduled. This signaling is conducted on a high-speed shared control channel (HS-SCCH), which is common to all users. The 10 HS-SCCH is transmitted two slots in advance of the corresponding HS-DSCH TTI. The HS-SCCH is encoded by a user equipment-specific mask and also contains lower layer control information, including the employed settings for modulation, coding scheme, channelization code, and H-ARQ. In addition to the above-described channels, every user equipment has an 15 associated dedicated physical channel (DPCH) in both the uplink and downlink directions. The downlink associated channel carries the signal radio bearer for :Layer 3 signaling as well as power control commands for the uplink channel. By contrast, me uplink channel is used as a feedback channel, which for example might carry the TPC commands for downlink power control. If needed, other services 20 (e.g., circuit-switched voice or video) can also be carried on the DPCH. The HSDPA concept also calls for an additional high-speed dedicated physical control channel (HS-DPCCH) in the uplink for carrying the Channel Quality Indicator (CQI) information in addition to the H-ARQ acknowledgements. Focusing now on the HS-SCCH, it is used to address the UE by the network. 25 The HS-SCCH carries the following information: 1. UE identity (16 bits): Xue 2. Channelization-code-set (7 bits): Xccs 3. Modulation scheme information (1 bit): Xma 4. Transport-block size information (6 bits): Xibs .30 5. Hybrid-ARQ process information (3 bits): Xhap •- •: .- 6. Redundancy and constellation version (3 bits): Xnd, 1. New data indicator (1 bit): Xna 12 Still, these errors are costly in terms of wasted power (e.g., a UE expending energy receiving and decoding HS-SCCH Part 2 and HS-PDSCH information that is not really intended for that UE) and lost time and bandwidth (e.g., to detect that a transmission was never received by an intended recipient, 5 and to retransmit that information). While this background section has focused on a specific example in connection with reception of HS-SCCH information in a 3GPP system, similar problems can arise in any communication system that relies on correlation techniques to determine whether information has been accurately detected, and 10 whether a decision should be made to abort further efforts to receive a multi-part message. A document, Texas Instruments: "HS-SCCH: Performance results and improved structure" 3GPP TSG RAN WGl MEETING 25, [Online] 9 April 2002 (2002-04-09), PARIS, FRANCE, retrieved from the Internet from 15 URL:http://www3gpp.org/ftp/tsg_ran/WGI_RLI/TSGRI_25/Docs/Zips/R1-02- 0535.zip discloses determining whether a received HS-SCCH is valid based on a comparison of a Viterbi maximum likelihood metric against a threshold. Still, it is desirable to provide methods and apparatuses that can employ correlation techniques to accurately receive and decode information in an efficient 20 manner in HSDPA as well as other systems. SUMMARY It should be emphasized that the terms "comprises" and "comprising", when used in this specification, are taken to specify the presence of stated features, integers, steps or components; but the use of these terms does not 25 preclude the presence or addition of one or more other features, integers, steps, components or groups thereof. In accordance with one aspect of the present invention, the foregoing and other objects are achieved in methods, apparatuses and machine'-readable storage media that determine whether to abort reception of a multi-part message in a code 30 division multiple access communication system. D COT A CEMENT SKRRT WO 2005/041465 7 PCT/EP2004/011147 The first three of the above are needed to be able to set up the RAKE receiver for reception of the HS-PDSCH - indeed the UE identity information is used by the UE to determine whether it is the intended recipient of the data that is about to be transmitted. Thus, the HS-SCCH is transmitted in two successive parts, 5 with the first three of the above being transmitted in Part 1 of the HS-SCCH. The remaining information is carried in Part 2 of the HS-SCCH. All Layer 1 (L1) information is transmitted on the HS-SCCH; that is, no L1 information is transmitted on the HS-PDSCH or DPCH. There can be up to a maximum of four HS-SCCH codes to monitor in a cell, 10 all transmitted with, a spreading fector of 128 and QPSK modulation. In order to allow time for decoding and setting up the receiver for reception in the UE, the HS-PDSCH sub-frame (which carries the user data) doesn't begin until two slots after the start of the HS-SCCH sub-frame. This is illustrated in FIG. 1, and described in greater detail in 3GPP TS 25 101 V5.5.0 (2003-09). This arrangement allows me 15 entire HS-SCCH Part 1 to be received and men decoded simultaneously with reception of the first slot of HS-SCCH Part 2. FIG. 2 is a flowchart depicting conventional actions performed within a UE in connection with the HS-SCCH. It should be understood that if the UE, due to its UE Category, has limits on inter-TTL, then mere has to be a certain distance between 20 TTIs with HS-PDSCH. This will make HS-SCCH reception unnecessary for some TTIs. Thus, an initial action taken by the UE is to wait until a next possible subrrame (step 201). Then, HS-SCCH Part 1 is received for up to four spreading codes (step 203). Next, two operations are performed in parallel: HS-SCCH Part 1 is decoded 25 (step 205) and slot 1 of HS-SCCH Part 2 is received for all possible codes (step 207). Which, if any, of these received HS-SCCH Part 2s to use will be decided by the Part 1 information. It needs to be determined whether the UE detected that the received HS-SCCH Part 1 is intended for this particular UE (decision block 209). If the answer is 30 "no" ("NO" path out of decision block 209), then there is no point in taking further steps to receive this HS-SCCH, and the process is aborted (step 211). In this case, processing will continue back at step 201. WO 2005/041465 PCT/EP2004/011147 8 If it has been determined that the decoded HS-SCCH Part 1 is intended for thiss UE ("YES" path out of decision block 209), then it is known which code, c, applies to this HS-SCCH. Processing then continues by using the spreading codes from the Part 1 decoding to set up the UE to receive the HS-PDSCH (step 213) and, 5 in parallel with this action, receiving the second slot of Part 2 for HS-SCCH associated with code c (step 215) and then decoding Part 2 of the HS-SCCH associated with code c (step 217). After the HS-SCCH Part 2 has been received and decoded, its CRC code can be checked to determine whether decoding has been successful (decision block 219). 10 If not ("NO" path out of decision block 219), then HS-PDSCH reception is aborted (step 221) and processing reverts back to step 201. If the HS-SCCH Part 2 decoding was successful ("YES" path out of decision block 219), than the UE is set up for reception of HS-PDSCH slot 3 according to code c (step 223). The UE is than set up to decode the HS-PDSCH using parameters 15 derived from HS-SCCH Part 2 decoding (step 225). Referring back to decision block 219, it should be understood that an unsuccessful decoding of HS-SCCH Part 2 can be the result of errors introduced in the HS-SCCH Part 2 itself, but it can also be the result of erroneously determining mat HS-SCCH Part 1 had been successfully detected. To show why this is so, the 20 following discussion will take a closer look at HS-SCCH Part 1. FIG. 3 illustrates the conventional process that is undertaken to construct the HS-SCCH information (both Parts 1 and 2). The Xccr and Xms parameters are combined by a multiplexer 301 to generate data denoted X1. As is conventional in the art, multiplexers 301 and 311 which concatenate inputs into an output are 25 illustrated without a selection control input. In order to generate the Part 1 portion of HS-SCCH, the data X1 is men convolutionally encoded by channel coding logic 303 that performs channel coding 1 to generate data denoted Z1. Rate matching logic 305 then performs Part 1 rate matching that transforms the data Z1 into data denoted R1. 30 L1 order to enable the UE to detect that it is the intended recipient of the HS-SCCH Part 1 message, UE masking logic 307 mat performs UE specific masking on R1 is then applied. The details of this masking will now be described in connection WO 2005/041465 PCT/EP2004/011147 9 with the logic diagram illustrated in FIG. 4. In one aspect of this logic, a unique code representing the UE that is the intended recipient is generated by applying convolutional coding logic 401 to die 16-bit Xue data to generate a 48-bit number denoted bi. Puncturing logic 403 is then applied to bi to generate a 40-bit number 5 denoted ci. The number ci is then applied as a mask to the data Rl by performing a logical exclusive-OR (XOR) operation 405 between the two values. The resulting value is denoted S1. The idea behind this masking is mat each UE receiving the HS-SCCH Part 1 message can apply its own known value of ci in a de-masking operation. For 10 example, where XOR is used as a masking function, then again applying me same ci value will un-do the original masking operation. If the resulting value is a useable RI vahie (i.e-, if RI is a valid codeword),this means mat me UE's value of the was the right one, and that UE is the intended recipient of the HS-SCCH. AU other UE*s win apply the wrong-valued ci, which will result in a non-decodable value, thus 15 informing each of those UE's mat it was not the intended recipient of the HS-SCCH Part 1 message. It has been determined mat the minimum Hamming distance between two masks (ci in FIG. 4) is 8. It is worth noting mat, while in principle, each UE applies masking to the received HS-SCCH Part 1 and men determines whether the resultant R1 is a valid 20 codeword, this is not necessary in practical embodiments. The reason for mis is because each UE is capable of knowing what its own HS-SCCH Part 1 ought to look like just prior to de-masking. Thus, more efficient embodiments can be implemented that skip the UE's own masking step. Referring back now to FIG. 3, the generation of HS-SCCH Part 2 25 information will now be described. In one aspect, r, s, and b parameters are provided to RV coding logic 309 to generate redundancy and constellation version information,Xrv. The Xrv information as well as Xibs,Xhap, and Xnd are combined in multiplexing logic 311 to generate X2 information. The Xi information along with Xue and X1 are then supplied to UE specific CRC attachment logic 313 to generate Y • : 30 information, Specifically; the UE specific attachment logic 313 combined the Part 1 information (X1) and Part 2 information (X2) and generates a CRC. The CRC is masked with the UE identity (Xue), and the result is appended to the Part 2 WO 2005/041465 PCTYEP2004/011147 10 information to generate the Y information. For more information regarding the operation of the UE specific CRC attachment logic, the interested reader should refer to the document 3GPP TS 25.212 V5.6.0 (2003-09), the entire contents of which are herein expressly incorporated by reference. This is then processed by 5 channel coding 2 logic 315 to generate Z2 information. The Z2 information is processed by rate matching 2 logic 317 to generate R2 information. Finally, the S1 information (from HS-SCCH Part 1 generation) and the R2 information are subjected to physical channel mapping logic 319 to yield the HS-SCCH. 10 Referring back to Part 1 detection (e.g., decision block 209 in FIG. 2), it is known to utilize a maximum likelihood (ML) algorithm to correlate the received HS-SCCH Part 1 information with all 256 possible hypothesized codewords RI (or St if masking is included). The ML method will now be explained in greater detail Introduce S1 as the received codeword on code cc[l,.,.ne]. In the 15 described approach de-masking is not done on me received codeword. Masking is instead included in the hypothesized codewords. An equivalent method is to work on de-masked received codewords R1. We model S' as: where ec is a noise vector containing impairments from imperfect 20 transmission/reception, and vc is a random vector due to the masking/de-masking arrangement In the example of HSDPA, X1 is an 8-bit vector. Therefore, there are 256 corresponding codewords S1 for any given UE. The codewords are enumerated If we introduce 25 L_ 13 In one aspect, this is determined by receiving a part of the multi-part message. Correlating the received part of the multi-part message with a known sequence generates a correlation value. The correlation value is compared with a threshold level. Reception of the multi-part message is aborted if the correlation 5 value is less than a threshold level. In another aspect, the threshold level is dynamically adjusted based on a communication traffic behavior. The communication traffic behavior may Se, for example, whether traffic directed to a particular user equipment (UE) is Part of a burst directed to that UE. 10 ] REPLACEMENT SHEET WO 2005/041465 14 PCT/EP2ft04/011147 In yet another aspect., detecting whether traffic directed to the particular UE is part of a burst directed to that UE comprises detecting whether the UE has been addressed at any time during a number, n, of the most recent transmission time intervals. The number, n, may, for example, be equal to 10. 5 In still another aspect, the threshold level may be permitted to assume any one of a plurality of possible threshold levels. In such embodiments, determining whether to abort reception of the multi-part message comprises ensuring mat the threshold level takes on a lower one of the plurality of possible threshold levels if it is detected mat traffic directed to the particular UE is part of a burst directed to that 10 UE; and ensuring that the threshold level takes on a higher one of the plurality of possible threshold levels if it is not detected that traffic directed to the particular UE is part of a burst directed to that UE. In some embodiments, the plurality of possible threshold levels may comprise only a low threshold level and a high threshold level In some embodiments,, the code division multiple access communication 15 system is a High Speed Downlink Packet Access (HSDPA) system, hi such embodiments, the part of the multi-part message might be a High Speed Shared Control Channel Part 1 (HS-SCCH Part 1) message. In still another aspect of the invention, the HSDPA system includes a full set of possible known sequences. However, the correlation value is one of a set of 20 correlation values that are generated by correlating each of a reduced set of possible known sequences against the HS-SCCH Part 1 message, wherein the reduced set of possible known sequences is generated from the full set of possible known sequences. The reduced set of possible known sequences may include, for example, only 25 those known sequences that signify something meaningful. In another aspect, the reduced set of possible known sequences may include, for example, only those known sequences that are associated with one or more capabilities of a first User Equipment (UE), wherein the full set of possible known sequences includes at least one known sequence that is not associated with one or 30 more capabilities of the first UE, and the at least one known sequence is associated with one or more capabilities of a second UE. then the decision matrix D is constructed as 5 The maximum likelihood detection for each code c is then found as the row number associated with the largest value in the corresponding column of D: To allow for comparison of ML estimates from different codes, estimates of the variance of vt + ef are formulated as 10 where "excl." means exclude element with index x, and in this case results in a new vector with one less element, i.e., without the peak. The detection can then be defined as 15 The UE identity masking is the only measure taken to provide enough reliable transmission of HS-SCCH Part 1 information. Unlike the Part 2 information, the Part 1 information is not protected by CRC coding. This is not absolutely critical, since a UE mistakenly believing that it has detected HS-SCCH 20 Part 1 information for itself will discover the mistake when the HS-SCCH Part 2 information doesn't check out (due to the use of an erroneous code c in the decoding process). Similarly, if a UE mistakenly fails to detect HS-SCCH Part 1 information, this too will be discovered when the transmitter notices that no ACK has ever been received for the subsequently transmitted data. 25 REPLACEMENT SHEET WO 2005/041465 15 PCT/EP2004/011147 BRIEF DESCRIPTION OF THE DRAWINGS The objects and advantages of the invention will be understood by reading the following detailed description in conjunction with the drawings in which: FIG. 1 is a timing diagram that illustrates the relationship between the start 5 of a HS-PDSCH sub-frame and the start of a HS-SCCH sub-frame. FIG, 2 is a flowchart depicting conventional actions performed within a UE in connection with the HS-SCCH. FIG. 3 illustrates a conventional process that is undertaken to construct HS-SCCH information (both Parts 1 and 2). 10 FIG. 4 is a logic diagram that illustrates details of UE masking logic that enables a UE to detect mat it is the intended recipient of an HS-SCCH Part 1 message. FIG. 5 is a flowchart that depicts exemplary logic that decodes HS-SCCH and dynamically adjusts a threshold level, T, in accordance with an exemplary 15 embodiment of the invention. FIG. 6 is a flowchart mat depicts exemplary logic that decodes HS-SCCH and dynamically adjusts a threshold level, T, in accordance with an alternative exemplary embodiment of the invention. FIG. 7 is a tree diagram illustrating possible decoding outcomes from a 20 number of scenarios of interest FIGS. 8-10 are graphs showing test results for tests with different thresholds for three methods described herein. FIGS. 11-13 are graphs that depict the performance of lie three herein-described methods for three HS-SCCH test cases. 25 DETAILED DESCRIPTION The various features of the invention will now be described with reference to the figures, in which like parts are identified with the same reference characters. The various aspects of the invention will now be described in greater detail in connection with a number of exemplary embodiments. To facilitate an 30 understanding of the invention, many aspects of the invention are described in terms WO 2005/041465 16 PCT/EP2004/OI1147 of sequences of actions to be performed by elements of a computer system. It will be recognized that in each of the embodiments, the various actions could be performed by specialized circuits (e.g., discrete logic gates interconnected to perform a specialized function), by program instructions being executed by one or 5 more processors, or by a combination of both. Moreover, the invention can additionally be considered to be embodied entirely within any form of computer readable carrier, such as solid-state memory, magnetic disk, optical disk or carrier wave (such as radio frequency, audio frequency or optical frequency carrier waves) containing an appropriate set of computer instructions that would cause a processor 10 to carry out the techniques described herein. Thus, the various aspects of the invention may be embodied in many different forms, and all such forms are contemplated to be within the scope of the invention. For each of the various aspects of the invention, any such form of embodiments may be referred to herein as "logic configured to" perform a described action, or alternatively as "logic that" 15 performs a described action. As mentioned in me Background section, it is possible to detect mat an HS-SCCH Part 1 message was erroneously detected (referred to herein as "false detection" or "false alarm") by relying on the failure of HS-SCCH Part 2 decoding. However, it is desirable to reduce current consumption by aborting HS-SCCH 20 decoding as soon as possible if a false detection is likely. Thus, in accordance with one aspect of the invention, false detection is recognized by testing the quality of the HS-SCCH Part 1 detection. More specifically, a threshold value, T, is introduced mat needs to be reached for a detection to be considered valid. This may be expressed as: 25 The discussion will now turn to techniques for assigning values to the threshold T. Tuning the decision threshold t calls for a tradeoff to be made between WO 2005/041465 17 PCT/EP2004/011147 the probability of false alarm ( P(Efa)) and the probability of missed detection ( p(Em )) (i-e., the'failure on the part of a UE to detect that an HS-SCCH Part 1 message really was intended for reception by that UE). Missed detection leads to decreased throughput, and false alarm leads to increased power consumption due to 5 starting HS-SCCH Part 2 decoding and HS-PDSCH decoding without being addressed by Node B, i.e., the base station. The best technique for tuning the value of T will depend upon what method is used to determine whether an HS-SCCH code correlation is likely to be a correct detection. In me Background section, one detection technique was described in 10 which a variance estimate is used to make this determination. However, a variance estimate could be quite complex to implement An alternative is to use a "standard deviation estimate", as follows: 11 With this modification, me detection algorithm is: Yet another (third) alternative implementation of a detection algorithm compares the ratio between largest correlation with the second largest correlation for each HS-SCCH code to a threshold T. 20 Regardless of which of the above or other detection algorithms are used, the influence of the threshold is such that a larger threshold will reduce the false alarm rate, but will also increase the probability of missed detection. Conversely, a decreased threshold yields the opposite relation. In accordance with another aspect of the invention, the harsh tradeoff results 25 that come from using a static threshold are relaxed by instead using an adaptation technique to dynamically adjust the threshold value, T, based on communication traffic behavior. One such behavior is whether or not traffic directed to a UE is part WO 2005/041465 18 PCT/EP2004/011H7 of a burst directed to that UE. Burst behavior typically occurs for file downloads, web surfing, and the like. In accordance with an embodiment of the invention, If the UE is in a burst, then a relatively low threshold value, T, should be used. This will yield some false alarms, but it will not jeopardize 5 throughput However, if the UE is not in a burst, then a relatively higher threshold value, t, is used. This will reduce the number of false alarms, and thereby reduce power consumption. However, the ability to detect a message will decrease slightly. 10 Any technique for detecting the existence of a burst may be used as part of the invention. One such technique is to declare mat a burst exists if the UE has been addressed at any time during some number, n, of the most recent TTTs. Conversely, if the UE has not been addressed daring any of the n most recent TTTs, then it is considered mat no burst exists. As an example, n can be set to 10 Of course, this 15 number can be adjusted to best suit the particular application. Another technique would be to declare that a burst exists if the UE has been addressed at least a number of times during the n most recent TTTs, wherein the number is larger man one. An implementation of the adaptive threshold, then, can be: { Tlgw if the UE has been addressed in any of the most recent n TIT s TUJ otherwise 20 where rlow and rhigh represent the respective relatively low and high values of the threshold, T. The threshold values xlow and Thigh should be tuned to yield desired performance. A potential danger with this approach is that the probability of missed detection will become so large with T = Thigh that the UE would not be able to detect that it is addressed after a transmission gap. However, it has been found (as will be 25 discussed in greater detail below) that the probability of missed detection can be made to increase only slightly by adjusting the threshold from Tlow toThigh that is, it can be made to change from 4% to 6%, or similar. At the same time, the probability of false alarm can be made to go from 50% (when rlow is active) down to 1% (when Thighi is active). \VO 2005/041465 19 PCT/EP2004/011147 A modification of the adaptive threshold technique can employ a filtered threshold. Specifically, an intermediate threshold t't is set to either tlow or thigh, tlow and thigh, being calculated as discussed above. The selection of tlow versus thigh as the intermediate threshold t't is based upon whether it is believed that a burst exists or a 5 burst does not exist t't is filtered by a known filtering technique, for example . is used as the threshold t. Another modification of the adaptive threshold technique can employ filtered values for the addressing of the UE. Specifically, a parameter xt is set to 1 if the UE was addressed in TTlt, and Xt is set to 0 if the UE was not addressed. xt is men 10 filtered using a known filtering method, for example The filtered value accounts for the recenmess of the addressing of the UE. To determine whether the UE is ma burst is compared to a threshold. The threshold which is compared to is not the same threshold T. This threshold is selected to balance false detections and missed detections. 15 As an alternative to the use of two threshold value (thigh and tlow), a plurality of thresholds can be employed to form a continuous spectrum of threshold values. •Which of the plurality of threshold values to employ is determined based upon the recenmess of addressing of the UE. FIG, 5 is a flowchart that depicts exemplary logic mat decodes HS-SCCH 20 and dynamically adjusts a threshold level, T , in accordance with an exemplary embodiment of the invention. Steps 501,503, 505, and 507 operate the same as their counterpart steps 201,203,205, and 207, and therefore need not be described here in detail. At the point of entering decision block 509, it needs to be determined 25 whether the UE detected that the received HS:SCCH Part 1 is intended for this particular UE. To make this determination, any of the above-described tests involving comparison of a detection-indicating value (e.g., a correlation value or its equivalent) with the threshold level r is used. If the answer is "no" ("NO" path out of decision block 509), then there is no point in taking further steps to receive this 30 HS-SCCH, and the process is aborted (step 511). "Since'traffic behavior may also have changed, the threshold level r is potentially adjusted (step 513). In the WO 2005/041465 20 PCIYEP2004/011147 exemplary embodiment in which the presence or absence of a burst is the relevant traffic behavior, the threshold level t is set to (or kept at) its high value, thigh if it is determined that there is no ongoing burst of data directed to the UE. If there is the possibility mat there continues to be an ongoing burst, despite the fact that the UE 5 appears not to have been addressed by this particular HS-SCCH sub-frame, then the threshold level T may be kept at an already existing low value, tlow .Processing then continues back at step 501. If it has been determined mat me decoded HS-SCCH Part 1 is intended for mis UE ("YES" path out of decision block 509), then it is known which code, c, 10 applies to mis HS-SCCH. Processing men continues by using the spreading codes from the Part 1 decoding to set up the HE to receive the HS-PDSCH (step 515) and, in parallel with this action, receiving the second slot of part 2 for HS-SCCH associated with code c (step 517) and than decoding part 2 of the HS-SCCH associated with code c (step 519). 15 After the HS-SCCH Part 2 has been received and decoded, its CRC codecan be checked to determine whether decoding has been successful (decision block 521). If not ("NO" path out of decision block 521), then HS-PDSCH reception is aborted (step 523). It should be noted that the decoding of HS-SCCH Part 2 might have failed for any of a number of reasons. One possibility is that the Part 1 detection 20 may have been a false alarm. This means that the UE was not really the intended recipient of the HS-SCCH. Alternatively, the failure to successfully decode Part 2 may have been due to actual corruption of the Part 2 data upon reception. In this exemplary embodiment, it is assumed that the failure is due to the existence of a false alarm. 25 Having taken the "NO" path out of decision block 521, it is once again possible that traffic behavior has changed since it was last checked. Thus, the threshold level T is potentially adjusted (step 525). hi the exemplary embodiment in which the presence or absence of a burst is the relevant traffic behavior, the threshold level r may be set to (or kept at) its high value thigh, if it is determined 30 that there is no ongoing burst of data directed to the UE. If there is the possibility that there continues to be an ongoing burst, despite the fact mat the UE appears not WO 2005/041465 21 PCT/EP2004/011147 to have been addressed by this particular HS-SCCH sub-frame, then the threshold level T may be kept at an already existing low value,tlow Processing (thann reverts back to step 501. If the HS-SCCH Part 2 decoding was successful ("YES" path out of decision 5 block 521), then Ihe UE is set up for reception of HS-PDSCH slot 3 according to code c (step 527). The UE is then set up to decode the HS-PDSCH using parameters derived from HS-SCCH Part 2 decoding (step 529). Also, the threshold level T is potentially adjusted (step 531) to account for the possibility that traffic behavior has changed since it was last checked In the exemplary embodiment in which the 10 presence or absence of a burst is the relevant traffic behavior, the threshold level t may be set to (or kept at) its low value, t low, if it is determined that mere is an ongoing burst of data directed to the UE (step 531). For example, using the exemplary test set forth above, me feet of coming through this path in me logic indicates that the UE has just been addressed. Thus, it is true that the UE has been 15 addressed within the most recent n TTTs, and the threshold level, T , should be decreased to (or maintained at) its low level,tlow If some other test for me presence of a burst is used, its outcome should be used to determine whether the threshold level, t, should be set to its low or high value. Processing then reverts back to step 501, 20 FIG. 6 is a flowchart that depicts exemplary logic that decodes HS-SCCH and dynamically adjusts a threshold level, t , in accordance with an alternative exemplary embodiment of the invention. Those blocks in FIG. 6 having like-numbered reference numerals as those depicted in FIG. 5 perform the same functions as their respective counterpart blocks in FIG. 5, and therefore need not be 25 described here further. The flowchart of FIG. 6 differs from FIG. 5 by not including block-525, and by instead including block 60-1. Referring to the "NO" path out of decision block 521 in FIG. 6, it will again be recalled that the decoding of HS-SCCH Part 2 might have failed for any of a number of reasons; One possibility is that the Part 1 detection may have been a false 30 alarm. This means that the UE was not really the intended recipient of the HS-SCCH. Alternatively, the failure to successfully decode Part 2 may have been due WO 2005/041465 22 PCT/EP2004/01I147 to actual corruption of the Part 2 data upon reception. In this alternative exemplary embodiment, it is assumed mat the UE really was the intended recipient of the HS-SCCH, and mat the failure is instead due to corruption of the Part 2 data upon reception. Accordingly, when it comes time to reevaluate whether the threshold 5 level r is set at an appropriate level, it is assumed mat burst conditions prevail. Thus, the threshold level should be set to (or kept at) a low level, t, (step 601). In all other respects, however, the logic depicted in FIG. 6 is identical to mat depicted in FIG. 5. Although the methods of FIG . 5 and 6 have been described in connection with two threshold levels, any of me different threshold levels discussed 10 above can be employed. Turning now to other improvements mat can be made to the Mis-algorithm introduced in me Background section, it is possible to reduce the complexity of the ML-algorimm in a number of ways. In one aspect of the invention, the number of codewords to correlate with can 15 be reduced from 256 to 240. An inspection of how Xccs is constructed (see 3GPP TS 25.212 V5.6.0 (2003-09)) reveals how this is possible. The Xccs (7 bits) is constructed as 20 where P is the starting code and O is the number of codes. Working through the above definition it turns out that Xccs, [112,... ,119] does not signal anything meaningful, and will thus not be used by Node B. In X1 formulation, it corresponds to the following set of codewords being illegal: X1, [224,... ,239]. With this simplification, the number of correlations to be made is reduced 25 from 256nc to 240ne (i.e., the number of rows in S^ is reduced). In another aspect, it is possible to reduce the number of pos sible codewords based on UE category. It is expected that most UE's will not be capable of receiving more than 5 or 10 spreading codes in parallel; some may not even be capable of v _ 16QAM reception.: This will limit the set of possible O, P andXms values further, 30 and thus reduce the number of possible codewords for a certain UE. The capability WO 2005/041466 23 PCT/EP2004/Oim7 of a UE in terms of multi-code and 16QAM reception is given by the UE Category (see 3GPP TS 25.306 V5.6.0 (2003-09) for details). Below, the number of possible codewords has been calculated for the different UE Categories: UE Category Max nr of codes 16QAM Size (XI) 1-6 5 Y 130 7-g 10 Y 210 9-10 15 Y 240 11-12 5 N 65 With this simplification, the number of correlations to be made is reduced from 240nc to 130nc fora 5-code terminal with 16QAM capability. This capability will be used in the test results that now follow. Tests have been conducted to determine the performance of the HS-SCCH 10 decoding methods described earlier. The simulation setups used are based on the HS-SCCH test cases defined in 3GPP TS 25.101 V5.5.0 (2003-09). In these tests, a genie path searcher has been used. There are three HS-SCCH tests defined in 3GPP TS 25.101 V5.5.0 (2003-09). The differences in the test cases are channel conditions (PAS or VA3O) and 15 location in the cell (1or 1 1oc = 0 or 5). The test is whether the UE under test has a probability of miss detection P(Em) less than a specification value at a certain Ec/Ior for the HS-SCCH. In me tests the UE is informed that the cell has four channel codes for HS-SCCH. The UE under test is addressed every third TTI in a pattern "...XOOXOOXOOX...". Specific UE identities to be used have been defined. 20 FIG. 7 is a tree diagram illustrating possible decoding outcomes from a number of scenarios of interest. The 3GPP test cases only specify a minimal performance in the left part of the graph (i.e., when the UE is addressed). The test quantity, probability of miss detection, is given by WO 2005/041465 24 PCT/EP2004/OJ1147 with the notation being taken from FIG. 7. The right side of the graph is, however, also of importance with respect to decreasing current consumption due to false alarms. As was shown earlier (see, e.g., FIG. 5), if a false alarm is generated, the UE will continue HS-SCOH decoding with Part 2, and set up the RAKE receiver for 5 HS-PDSCH reception. This analysis will not look into the "pathological" cases occurring when the CRC fails to certify that the detection was incorrect The probability for this event is 216 = 1.52e-5, that is, one CRC check in 65000. The error event will only happen when a false detection in Part 1 occurs and the CRC checks, which will occur 10 approximately once in a few hours. These error cases are quite severe, but will be handled by higher layers. The methods to be evaluated only differ in the method used for detecting whether a good enough correlation is found in HS-SCCH Part 1 decoding. The methods under test win be enumerated as follows. 15 Method Description 1 Comparing a variance estimation as described in the Background section with a threshold t. 2 Comparing the ratio between largest and the second largest correlation with a threshold T, as described earlier. 3 Comparing a simplified variance estimation, as described earlier, with a threshold T. In all cases it is assumed that the UE Category is 6 (i.e., 16QAM with 5 multi-codes). This assumption reduces the number of possible codewords to 130. FIGS. 8-10 are graphs showing test results for tests with different thresholds 20 for the three methods. More particularly, FIG. 8 deplete probabilities of miss detection and for false alarm for different threshold values, T when the tuning of Method 1 is employed. FIG. 9 depicts probabilities of miss detection and for false alarm for different threshold values, T when the tuning of Method 2 is employed. FIG. 10 depicts probabilities of miss detection and for false alarm for different 25 threshold values, T when the tuning of Method 3 is employed. WO 2005/041465 25 PCT/EP2004/011147 The tests were performed for the 3GPP HS-SCCH test cases, with a fixed HS-SCCH Ec/Ior (-11.5, -12, -13 for the test cases respectively). In FIGS. 8-10, the probabilities for miss detection and false alarm are shown for different values of the threshold, 9. ft can be seen that the trade-off between false alarm and miss detection 5 is quite tricky. Below one threshold that gave good probability of miss detection « and one threshold that gives reasonable probability for false alarm were chosen. These could be reasonable values to use in an adaptive threshold algorithm; otherwise, some compromise fixed threshold value would need to be used. Method Threshold 1 3.0 1 4.0 2 1.2 2 1.6 3 3,5 3 4.5 10 The lower threshold is designed to be used inside a traffic burst, while the higher is designed to be used between traffic bursts. The performance of the chosen methods and thresholds will now be evaluated in the HS-SCCH test cases defined in 3GPP TS 25.101 V5.5.0 (2003-09). 15 The test cases only require good enough performance on probability of miss detection, but to lower the power consumption the probability of false alarm has to be considered as well. False alarm probability is not dependent on HS-SCCH Ec /Ior because no HS-SCCH is sent to the UE when there is a false alarm. The false alarm 20 probabilities simulated for different methods and thresholds are: WO 2005/041465 26 PCT/EP2004/011147 Method Test case Threshold False alarm probability 1 1 3.0 55% 1 2 3.0 55% 1 3 3.0 55% 1 1 4.0 1.8% 1 2 4.0 1.9% 1 3 4.0 1.7% 2 1 1.2 70% 2 2 1.2 71% 2 3 1.2 70% 2 1 1.6 6.2% 2 2 16 6.4% 2 3 1.6 5.7% 3 1 3.5 62% 3 2 3.5 60% 3 3 3.5 61% 3 1 4.5 3.8% 3 2 4.5 3.6% 3 3 4.5 3.2% As seen from the false alarm probabilities above, Method 2 is clearly worse man the others. Method 1 seams slightly better than Method 3. 5 The discussion will now turn to the probability of miss detection, P(Em). FIGS. 11-13 are graphs that depict the performance of the three methods for the three HS-SCCH test cases. More particularly, FIG. 11 is a graph depicting the performance of decoding Methods 1,2, and 3 for the 3 GPP HS-SCCH test case 1. FIG. 12 is a graph depicting the performance of decoding Methods 1,2, and 3 for 10 the 3GPP HS-SCCH test case 2. And, FIG. 13 is a graph depicting the performance of decoding Methods 1,2, and 3 for the 3GPP HS-SCCH test case 3. WO 2005/041465 27 PCT/EP2004/011147 From the performance tests, it is clearly seen that Method 2 is outperformed by the other two methods, both in probability of miss detection and probability of false alarm. The performance gap is less between Method 1 and Method 3. Method 1 is however slightly better in both probability of miss detection and probability of 5 false alarm. If the adaptive threshold method described earlier is implemented, the following implementation margins (i e., shown as the distance between the low threshold curve and the 3GPP specification point) are obtained: Method Test case Implementation Margin (dB) 1 1 2,8 1 2 2.6 1 3 3.1 2 1 2l 2 2 2.1 2 3 1.7 3 1 2.6 3 2 2.4 3 3 2.5 10 The following conclusions are reached: Methods for HS-SCCH Part 1 decoding have been described and analyzed. All of the studied methods build on the ML-method correlating with all possible codewords. The complexity of the ML- correlations was decreased by observing limitations in the number of possible 15 codewords. The decrease of possible codewords came from some being unused, and in some cases due to not using the highest UE Category. With respect to the problem of how to detect whether the network is addressing the UE, three methods with different complexity have been described. The three methods perform differently in terms of probability of miss detection and 20 probability of false alarm. One method was however judged as better than the other two. WO 2005/041465 28 PCT/EP2004/011147 To avoid the tradeoff between probability of miss detection and probability of false alarm, an adaptive method for control of the decision threshold has been described. With the proposed HS-SCCH decoding algorithms 2.6-3.IdB in 5 implementation margin is obtained, compared to the 3GPP specification point. The invention has been described with reference to particular embodiments. However, it will be readily apparent to those skilled in the art that it is possible to embody the invention in specific forms other than those of the preferred embodiment described above. This may be done without departing from the spirit of 10 the invention. It should be noted that the UE may perform the Part 1 decoding in different ways, depending on whether or not it is in a burst. Generally, the UE can handle the reception of HS-SCCH Part 1 information in different ways, depending on whether it is in a burst or not 15 Thus, the preferred embodiment is merely illustrative and should not be considered restrictive in anyway. The scope of the invention is given by the appended claims, rather than the preceding description, and all variations and equivalents which fall within the range of the claims are intended to be embraced therein. 20 29 WHAT IS CLAIMED IS: 1. A method of determining whether to abort reception of a multi-part message in a code division multiple access communication system, comprising: ; receiving (503) a part of the multi-part message; 5 generating a correlation value (505) by correlating the received part of the multi-part message with a known sequence; comparing the correlation value with a threshold level (509); aborting reception of the multi-part message (511) if the correlation value is less than a threshold level; and 10 dynamically adjusting the threshold level (513, 525, 531) based on a communication traffic behavior. 2. The method of claim 1, wherein the comprising step is performed as: 15 wherein c is a code, MLc is a maximum likelihood detection for each code c, D is 20 a decision matrix, Vc is a variance of code c, t is a threshold, ne is an index corresponding to a number of codes, X1_dctection is the resulting code word number, and MLc detection is the number of the code word giving the largest correlation for spreading code c_detection. 25 3. The method of claim 1, wherein the comparing step is performed as: where wherein c is a code, MLc is a maximum likelihood detection for each code c, D is a decision matrix, Sc is a standard deviation of code c, r is a threshold, nc is an index corresponding to a number of codes, X1 detection is the resulting code word 10 number, and MLc detection is the number of the code word giving the largest correlation for spreading code c detection. 4. The method of claim 1, wherein the comparing step is performed by comparing a ratio between a highest correlation and a second highest correlation 15 with a threshold. 5. The method of claim 1, wherein the communication traffic behavior is whether traffic directed to a particular user equipment (UE) is part of a burst directed to that UE. 20 6. The method of claim 5, wherein detecting whether traffic directed to the particular UE is part of a burst directed to that UE comprises: detecting whether the UE has been addressed at any time during a number, n, of the most recent transmission time intervals. 25 7. The method of claim 6, wherein the number, n, is equal to 10. 8. The method of claim 1, where in the communication traffic behavior accounts for the recentness of traffic addressed to a particular UE. 30 REPLCEMENT SHEET 31 9. The method of claim 1, wherein the threshold level is permitted to assume any one of a plurality of possible threshold levels. 10. The method of claim 9, comprising: 5 if it is detected that traffic directed to the particular UE is part of a burst directed to that UE, then ensuring that the threshold level takes on a lower one of the plurality of possible threshold levels; and if it is not detected that traffic directed to the particular UE is part of a burst directed to that UE, then ensuring that the threshold level takes on a higher 10 one of the plurality of possible threshold levels. 11. The method of claim 9, wherein the plurality of possible threshold levels consists of a low threshold level and a high threshold level. 15 12. The method of claim 9, wherein an intermediate threshold is set to one of the plurality of possible threshold levels, and the intermediate threshold is filtered. 13. The method of claim 1, wherein the code division multiple access 20 communication system is a High Speed Downlink Packet Access (HSDPA) system. 14. The method of claim 13, wherein the part of the multi-part message is a High Speed Shared Control Channel Part 1 (HS-SCCH Part 1) message. 25 15. The method of claim 14, wherein: the HSDPA system includes a full set of possible known sequences; the correlation value is one of a set of correlation values that are generated . by correlating each of a reduced set of possible known sequences against the HS-30 SCCH Part 1 message; and 32 the reduced set of possible known sequences is generated from the full set of possible known sequences. 16. The method of claim 15, wherein the reduced set of possible known 5 sequences includes only those known sequences that signify something meaningful. 17. The method of claim 15, wherein: the reduced set of possible known sequences includes only those known 10 sequences that are associated with one or more capabilities of a first User Equipment (UE); and the full set of possible known sequences includes at least one known sequence that is not associated with one or more capabilities of the first UE, and the at least one known sequence is associated with one or more capabilities of a 15 second UE. ] 8. A method of decoding a High Speed Shared Control Channel Part 1 (HS- SCCH Part 1) message in a High Speed Downlink Packet Access (HSDPA) system that includes a full set of possible codewords, the method comprising: 20 receiving the HS-SCCH Part 1 message; generating a set of correlation values by correlating each of a reduced set of possible codewords, against the received HS-SCCH Part 1 message; and selecting as a decoded value that one of the reduced set of possible codewords that is associated with a highest one of the correlation values, 25 wherein the reduced set of possible codewords is generated from the full set of possible codewords. 19. The method of claim 18, wherein the reduced set of possible codewords includes only those codewords that signify something meaningful. 30 20. The method of claim 18, wherein: REPLACEMENT SHEET 33 the reduced set of possible codewords includes only those codewords that are associated with one or more capabilities of a first User Equipment (UE); and the fall set of possible codewords includes at least one codeword that is not associated with one or more capabilities of the first UE, and the at least one 5 codeword is associated with one or more capabilities of a second UE. 21. An apparatus that determines whether to abort reception of a multi-part message in a code division multiple access communication system, the apparatus comprising: 10 logic that receives (503) a part of the multi-part message; logic that generates a correlation value (505) by correlating the received part of the multi-part message with a known sequence; logic that compares the correlation value with a threshold level (509); logic that aborts reception of the multi-part message (511) if tbe 15 correlation value is less than a threshold level; and logic that dynamically adjusts the threshold level (513,525, 531) based on a communication traffic behavior. 22. The apparatus of claim 21, wherein the logic that compares performs: 20 25 wherein c is a code, MLC is a maximum likelihood detection for each code c, D is a decision matrix, Vc is a variance of code c, t is a threshold, nc is an index corresponding to a number of codes, X 1 detection is the resulting code word number, and MLc_detection is the number of the code word giving the largest correlation for spreading code c_detection. REPLACEMENT SHEET 23. The apparatus of claim 21, wherein the logic that compares performs: where 10 wherein c is a code, MLc is a maximum likelihood detection for each code c, D is a decision matrix, Se is a standard deviation of code c, r is a threshold, nc is an index corresponding to a number of codes, X1 detection is the resulting code word 15 number, and MIc_ detection is the number of the code word giving the largest correlation for spreading code c_detection. 24. The apparatus of claim 21, wherein the logic that compares a ratio between a highest correlation and a second highest correlation with a threshold. 20 25. The apparatus of claim 21, wherein the communication traffic behavior is whether traffic directed to a particular user equipment (UE) is part of a burst directed to that UE. 25 26. The apparatus of claim 25, wherein the logic that detects whether traffic directed to the particular UE is part of a burst directed to that UE comprises: logic that detects whether the UE has been addressed at any time during a number, n, of the most recent transmission time intervals. REPLACEMENT SHEET 27. The apparatus of claim 26, wherein the number, n, is equal to 10. 28. The apparatus of claim 21, wherein the communication traffic behavior 5 accounts for the recentness of traffic addressed to a particular UE. 29. The apparatus of claim 21, wherein the threshold level is permitted to assume any one of a plurality of possible threshold levels. 10 30. The apparatus of claim 29 comprising: logic that ensures that the threshold level takes on a lower one of the plurality of possible threshold levels if it is detected that traffic directed to the particular UE is part of a burst directed to that UE; and logic that ensures that the threshold level takes on a higher one of the 15 plurality of possible threshold levels if it is not detected that traffic directed to the particular UE is part of a burst directed to that UE. 31. The apparatus of claim 29, wherein the plurality of possible threshold levels consists of a low threshold level and a high threshold level. 20 32. The apparatus of claim 29, wherein an intermediate threshold is set to one of the plurality of possible threshold levels, and the intermediate threshold is filtered. 25 33. The apparatus of claim 21, wherein the code division multiple access communication system is a High Speed Downlink Packet Access (HSDPA) system. 34. The apparatus of claim 33, wherein the part of the multi-part message is a 30 High Speed Shared Control Channel Part 1 (HS-SCCH Part 1) message. REPLACEMENT SHEET 36 35. The apparatus of claim 34, wherein: the HSDPA system includes a full set of possible known sequences; . the correlation value is one of a set of correlation values that are generated . by correlating each of a reduced set of possible known sequences against the HS-5 SCCH Part 1 message; and the reduced set of possible known sequences is generated from the full set of possible known sequences. 36. The apparatus of claim 35, wherein the reduced set of possible known 10 sequences includes only those known sequences that signify something meaningful. 37. The apparatus of claim 35, wherein: the reduced set of possible known sequences includes only those known 15 sequences tbat are associated with one ot more capabilities of a first User Equipment (UE); and the full set of possible known sequences includes at least one known sequence that is not associated with one or more capabilities of the first UE, and the at least one known sequence is associated with one or more capabilities of a 20 second UE. 38. An apparatus that decodes a High Speed Shared Control Channel Part 1 (HS-SCCH Part 1) message in a High Speed Downlink Packet Access (HSDPA) system that includes a full set of possible codewords, the apparatus comprising: 25 logic that receives the HS-SCCH Part 1 message; logic that generates a set of correlation values by correlating each of a reduced set of possible codewords against the received HS-SCCH Part 1 message; and logic that selects as a decoded value that one of the reduced set of possible 30 codewords that is associated with a highest one of the correlation values, REPLACEMENT SHEET 30 -35= wherein the reduced set of possible codewords is generated from the full set of.possible codewords. 39. Tbe apparatus of claim 38, wherein the reduced set of possible codewords 5 includes only those codewords that signify something meaningful. 40. The method of claim 38, wherein: the reduced set of possible codewords includes only those codewords that are associated with one or more capabilities of a first User Equipment (UE); and J 0 the full set of possible codewords includes at least one codeword that is not associated with one or more capabilities of tbe first UE, and the at least one codeword is associated with one or more capabilities of a second UE. 15 41. A machine readable storage medium having stored thereon one or more instructions that cause a processor to determine whether to abort reception of a multi-part message in a code division multiple access communication system, the one or more instructions causing the processor to perform: receiving (503) a part of the multi-part message; generating a correlation value (505) by correlating the received part of the 20 multi-part message with a known sequence; comparing the correlation value with a threshold level (509); aborting reception of the multi-part message (511) if the correlation value is less than a threshold level; and dynamically adjusting the threshold level (513, 525, 531) based on a 25 communication traffic behavior. 42. The machine-readable storage medium of claim 41, wherein the communication traffic behavior is whether traffic directed to a particular user equipment (UE) is part of a burst directed to that UE. 30 REPLACEMENT SHEET 38 43. The machine readable storage medium of claim 42, wherein detecting whether traffic directed to the particular UE is part of a burst directed to that UE comprises : detecting whether the UE has been addressed at any time during a number, 5 n, of the most recent transmission time intervals. 44. A machine readable storage medium having stored thereon one or more instructions that cause a processor to decode a High Speed Shared Control Channel Part 1 (HS-SCCH Part 1) message in a High Speed Downlink Packet 0 Access (HSDPA) system that includes a full set of possible codewords, the one or more instructions causing the processor to perform: receiving the HS-SCCH Part I message; generating a set of correlation values by correlating each of a reduced set of possible codewords against the received HS-SCCH Part 1 message; and 5 selecting as a decoded value that one of the reduced set of possible codewords that is associated with a highest one of the correlation values, wherein the reduced set of possible codewords is generated from the full set of possible codewords. 45. A method of determining whether to abort reception of a multi-part message in a code division multiple access communication system; a method of decoding a High Speed Shared Control Channel Part 1 (HS-SCCH Part 1) message in a High Speed Downlink Packet Access (HSDPA); an apparatus determines whether to abort reception of a multi-part message in a code division multiple access communication system; an apparatus of decoding a High Speed Shared Control Channel Part 1 (HS-SCCH Part 1) message in a High Speed Downlink Packet Access (HSDPA); and a machine readable storage medium having stores one or more instructions that cause a processor to determine whether to abort reception of a multi-part message in a code division multiple access communication system, such as herein described with reference to the accompanying drawings. Dated this 20th day of March 2006. OMANA RAMAKRISHNAN Of K & S PARTNERS AGENT FOR THE APPLICANT(S) REPLACEMENT SHEET

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336-MUMNP-2006-ABSTRACT(23-3-2011).pdf

336-mumnp-2006-abstract(24-03-2006).doc

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336-MUMNP-2006-CORRERESPONDENCE(12-9-2011).pdf

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336-mumnp-2006-correspondence(25-09-2006).pdf

336-MUMNP-2006-CORRESPONDENCE(28-9-2006).pdf

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336-mumnp-2006-description(complete)-(24-03-2006).pdf

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336-MUMNP-2006-DRAWING(23-3-2011).pdf

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336-mumnp-2006-form 1(3-4-2006).pdf

336-mumnp-2006-form 18(28-09-2006).pdf

336-mumnp-2006-form 2(24-03-2006).doc

336-mumnp-2006-form 2(24-03-2006).pdf

336-MUMNP-2006-FORM 2(GRANTED)-(16-2-2012).pdf

336-MUMNP-2006-FORM 2(TITLE PAGE)-(23-3-2011).pdf

336-mumnp-2006-form 2(title page)-(24-03-2006).pdf

336-MUMNP-2006-FORM 2(TITLE PAGE)-(24-3-2006).pdf

336-MUMNP-2006-FORM 2(TITLE PAGE)-(GRANTED)-(16-2-2012).pdf

336-MUMNP-2006-FORM 26(24-3-2006).pdf

336-MUMNP-2006-FORM 3(23-3-2011).pdf

336-mumnp-2006-form 3(24-3-2006).pdf

336-mumnp-2006-form 5(24-3-2006).pdf

336-mumnp-2006-general power of attorney(24-3-2006).pdf

336-MUMNP-2006-PETITION UNDER RULE 137(23-3-2011).pdf

336-MUMNP-2006-REPLY TO EXAMINATION REPORT(23-3-2011).pdf

336-MUMNP-2006-REPLY TO HEARING(6-2-2012).pdf

336-mumnp-2006-wo international publication report(24-3-2006).pdf