CN101128990A - Adaptation of transmit subchannel gains in a system with interference cancellation - Google Patents

Abstract

A method and system for interference cancellation (IC). One aspect relates to traffic interference cancellation. Another aspect relates to joint IC for pilot, overhead and data. Another aspect relates to improved channel estimation. Another aspect relates to adaptation of transmit subchannel gains.

Description

The self adaptation that has transmit subchannel gains in the system of interference eliminated

Priority based on 35U.S.C. § 119 requirements

The application requires the priority of the commonly assigned U.S. Provisional Application No.60/638666 of application on December 23rd, 2004, the title of this provisional application is " TRAFFICINTERFERENCE CANCELLATION AT THE BTS ON A CDMAREVERSE LINK ", is incorporated herein this application for your guidance.

Technical field

The present invention relates generally to wireless communication system, be specifically related to the traffic carrying capacity interference eliminated in the wireless communication system.

Background technology

Communicating by letter between communication system can provide the base station and access terminal.Forward link or down link refer to from the base station to the transmission that accesses terminal (transmission).Reverse link or up link refer to from the transmission of the base station that accesses terminal.Each access terminal can the given moment with forward direction link and reverse link and one or more base station communication, this depend on access terminal whether be start and whether access terminal and be in soft handover.

Description of drawings

According to the detailed description that following connection with figures proposes, the application's feature, essence and advantage will become clearly.Similar Reference numeral can be represented identical or similar object with character.

Fig. 1 illustrates the wireless communication system that has the base station and access terminal.

The structure and/or the process (process) of the exemplary transmitter of realizing on Fig. 2 illustrates and can access terminal in Fig. 1.

Fig. 3 illustrates the process and/or the example of structure of the receiver that can realize on the base station in Fig. 1.

Fig. 4 illustrates another embodiment of the process or the structure of base station receiver.

Fig. 5 illustrates among Fig. 1 the general example of three users' distribute power in the system.

The even time migration that Fig. 6 illustrates for the frame asynchronous service amount interference eliminated of using equal transmit power distributes.

Fig. 7 illustrates the pilotaxitic texture that is used for reverse link data packets and the automatic re-send request may channel of forward link.

Fig. 8 illustrates the memory of striding complete 16 time slots grouping.

Fig. 9 A illustrates the method for the traffic carrying capacity interference eliminated of the order interference eliminated (SIC) of the nothing delay decoding of example.

Fig. 9 B illustrates the equipment of method among the execution graph 9A.

Receiver sample buffer after the continuous son grouping that Figure 10 is illustrated in pilotaxitic texture reaches,

Wherein eliminated through the son grouping of decoding and disturbed.

Figure 11 illustrates overhead channels structure.

Figure 12 A illustrates and at first carries out pilot tone IC (PIC), then the method for executive overhead IC (OIC) and traffic carrying capacity IC (TIC) together.

Figure 12 B illustrates the equipment of method among the execution graph 12A.

Figure 13 A illustrates the variant of method among Figure 12 A.

Figure 13 B illustrates the equipment of method among the execution graph 13A.

Figure 14 A illustrates associating PIC, the method for OIC and TIC carried out.

Figure 14 B illustrates the equipment of method among the execution graph 14A.

Figure 15 A illustrates the variant of method among Figure 14 A.

Figure 15 B illustrates the equipment of method among the execution graph 15A.

Figure 16 illustrates the model of emission system.

Figure 17 illustrates the example response that transmits and receives filtering to combination.

Figure 18 A and 18B illustrate the example that refers to the channel estimating (real part and imaginary part) of the multiplex (MUX) that each place estimates in (finger) based on three RAKE rakes.

Figure 19 A-19B illustrates with RAKE rake and refers to and the example of the improved channel estimating that despreads to the basis of carrying out with data chips.

Figure 20 A illustrates the RAKE rake and refers to that delay place comes the method for despreading with the data chips of regeneration.

Figure 20 B illustrates the equipment of method among the execution graph 20A.

Figure 21 A and 21B illustrate the example of estimating compound channel with the evenly spaced sample of 2 times of chip resolution.

Figure 22 A illustrates the method for estimating compound channel with the data chips of regeneration with even resolution.

Figure 22 B illustrates the equipment of method among the execution graph 22A.

Figure 23 illustrates the closed power control and the gain controlling of carrying out with fixed overhead subchannel gain.

Figure 24 illustrates the power control carried out with fixed overhead subchannel gain among Figure 23 and the variant of gain controlling.

Figure 25 illustrates the example of the power control of carrying out with the fixed overhead subchannel.

Figure 26 is similar to Figure 24, except overhead gain control.

Figure 27 only illustrates the variant with the Figure 26 that carries out the control of DRC overhead gain.

Embodiment

Any embodiment described here is not necessarily preferred or favourable with respect to other embodiment.Although different aspect of the present disclosure provides in the drawings, accompanying drawing is not necessarily drawn in proportion or is drawn fully.

Fig. 1 illustrates wireless communication system 100, and it comprises system controller 102, base station 104a-104b and a plurality of 106a-106h that accesses terminal.This system 100 can have the controller 102 of any amount, base station 104 and access terminal 106.Following different aspect of the present disclosure and embodiment can carry out in system 100.

Accessing terminal 106 can be that move or static, and can be dispersed in the whole communication system shown in Figure 1 100.Access terminal and 106 can be connected to as the calculation element of laptop PC or in calculation element, carry out.Replacedly, accessing terminal can be self-contained data set, as PDA(Personal Digital Assistant).Accessing terminal 106 can refer to polytype device, as wired phone, radio telephone, cell phone, laptop computer, radio communication personal computer (PC) card, PDA, external or internal modem etc.Accessing terminal can be by wireless channel or wire message way, for example uses optical fiber or coaxial cable communication that any device that provides data to connect as the user is provided.Access terminal and to have different titles, as mobile radio station, access unit, subscriber unit (subscriber unit), mobile device, portable terminal, mobile unit, mobile phone, travelling carriage, distant station, remote terminal, remote unit, user's set, subscriber equipment, hand-held device, or the like.

System 100 provides communication for many sub-districts, and each sub-district is by 104 services of one or more base stations here.Base station 104 also can refer to a part, modem pool transceiver (MPT) or the Node B of base transceiver systems (BTS), access point, Access Network.The network equipment that Access Network refers at Packet Switch Data Network (as the internet) and accesses terminal and provide data to connect between 106.

Forward link (FL) or down link refer to from the base station 104 to accessing terminal 106 transmission.Reverse link (RL) or up link refer to from 106 104 the transmission to the base station that access terminal.

Base station 104 can be used the data rate of selecting from one group of different pieces of information speed to transmit the data to and be accessed terminal 106.106 Signal to Interference plus Noise Ratio (SINR) that can measure by base station 104 pilot transmitted signals that access terminal, and for determining desired data rates to the 106 emission data that access terminal in base station 104.Accessing terminal 106 can send data request channel or data rate control (DRC) message to base station 104, thereby with desired data rates informing base station 104.

System controller 102 (also referring to base station controller (BSC)) can provide the coordination and the control of base station 104, and can further control through the base station 104 routes to 106 the calling of accessing terminal.System controller 102 can further be coupled to PSTN (PSTN) through mobile switching centre (MSC), and is coupled to Packet Data Network through group data service node (PDSN).

Communication system 100 can be used one or more communication technologys, as code division multiple access (CDMA), IS-95, HRPD (high rate packet data) (HRPD), be also referred to as high data rate (HDR), as regulation in " cdma2000High Rate Packet Data Air Interface Specification " like that, TIA/EIA/IS-856, data-optimized (EV-DO), the IXEV-DO of CDMA 1X evolution, wideband CDMA (WCDMA), universal mobile telecommunications system (UMTS), TD SDMA access (TD-SCDMA), OFDM (OFDM), or the like.The example that describes below provides details for clear understanding.Idea given here also can be applied to other system, and current example is not in order to limit the application.

Fig. 2 illustrates the example of the structure and/or the process of transmitter, and it can access terminal in Fig. 1 and carry out on 106.Function shown in Figure 2 and parts can pass through software, hardware, or the combination of software and hardware realizes.Except function shown in Figure 2, other function also can be added among Fig. 2 or be replaced function among Fig. 2.

Data source 200 provides data to encoder 202, thereby this encoder uses one or more encoding schemes to provide the coded data chip to the data bits of encoded.Each encoding scheme can comprise the coding of one or more types, as Cyclic Redundancy Check, and convolutional encoding, Turbo coding, block encoding (block coding), the coding of other types, or basic not coding.Other encoding scheme can comprise automatic re-send request may (ARQ), hybrid ARQ (H-ARQ), and incremental redundancy repeat techniques.Data of different types can be different encoding scheme coding.The opposing decline thereby the data bit behind 204 pairs of codings of interleaver interweaves.

Thereby modulator 206 is modulated data encoded, that interweave and is produced modulated data.The example of modulation technique comprises two-phase phase shift keying (BPSK) and quarternary phase-shift keying (QPSK) (QPSK).Modulator 206 also can be retransmitted modulated data sequence, or symbol is deleted surplus unit (symbol puncture unit) and sign bit can be deleted surplus.Modulator 206 also can cover sign indicating number (Walsh cover) (being the Walsh sign indicating number) thereby the modulated data formation of expansion data chips by Walsh.Thereby modulator 206 also can pilot chip and the MAC chip come time multiplexing date chip generated code laminar flow.Modulator 206 also can use Pseudo-Random Noise Code (PN) expander to come the extended code laminar flow with one or more PN sign indicating numbers (as short code, long code).

Base band-radio frequency (RF) converting unit 208 can be converted to baseband signal the RF signal, so that be emitted to one or more base stations 104 through antenna 210 on wireless communication link.

Fig. 3 illustrates the process and/or the example of structure of receiver, and it can be carried out in the base station 104 in Fig. 1.Function shown in Figure 3 and parts can softwares, and the combination of hardware or software and hardware is implemented.Except function shown in Figure 3, other function also can be added into Fig. 3 or replace the function of Fig. 3.

One or more antennas 300 receive from one or more reverse link modulated signals of 106 of accessing terminal.The path effects that a plurality of antennas can provide space various (spatial diversity) to worsen with opposing is as decline.The signal of each reception is provided for each receiver or RF arrives baseband conversion unit 302, its adjusting (, amplifying the conversion of frequency reducing rate) and the signal that digitlization received as filtering, thus be the signal generation data sample of this reception.

But the signal that demodulator 304 demodulation are received, thereby provide the symbol of reduction.For CDMA2000, resume data transmission is in the following way attempted in demodulation, (1) thus channelizing through the sample of expansion with the data that received and pilot tone is isolated or channelizing to code channel (code channel) separately and (2) thus provide through demodulated data with the data of the pilot tone coherent demodulation channelization recovered.Demodulator 304 can comprise and receives sample buffer 312 (being also referred to as associating front end RAM (FERAM) or sample RAM), harrow type receiver 314 and through demodulated symbols buffer 316 (be also referred to as rear end RAM (BERAM) or through demodulated symbols RAM).Wherein, receive the sample that sample buffer 312 is used to all users/storage received signal that accesses terminal, harrow type receiver 314 is used for despreading and handle a plurality of signal examples.Can have a plurality of through demodulated symbols buffer 316 with a plurality of users/access terminal corresponding.

Deinterleaver 306 deinterleavings are from the data of demodulator 304.

Thereby the modulated data of decoder 308 decodable codes are recovered the data bit through decoding by 106 emissions that access terminal.Data through decoding can be offered data sink 310.

Fig. 4 illustrates another embodiment of base station receiver flow process or structure.In Fig. 4, the bits of user data that success is decoded is imported into interference reconstruction unit 400, and it comprises encoder 402, interleaver 404, modulator 406 and filter 408.Encoder 402, interleaver 404 and modulator 406 can be similar to encoder 202, interleaver 204, the modulator 206 among Fig. 2.Filter 408 is with the user sample of FERAM resolution formation through decoding, as changing into 2 times of spreading rates from 1 times of spreading rate.The decoder user is from FERAM 312 they to be removed or eliminate to the contribution of FERAM.

Though the interference eliminated of base station 104 is described below, the notion here may be used on accessing terminal 106 or any other parts of communication system in.

The traffic carrying capacity interference eliminated

The CDMA reverse chain-circuit capacity can be subjected to the interference-limited between the user, because the signal of different user emission is not a quadrature at BTS 104 places.Therefore, the technology that reduces inter-user interference will be improved the systematic function of CDMA reverse link.Here described cdma system, implemented the technology of effective interference eliminated as CDMA20001xEV-DO-RevA for the advanced person.

Traffic carrying capacity, pilot tone and the overhead signal of each DO RevA user terminal emission all can cause the interference to other users.As shown in Figure 4, at BTS 104 places, signal can deduct by reconstruct and from front end RAM 312.The pilot transmitted signal at BTS 104 places be known and can based on about the knowledge of channel by reconstruct.Yet, overhead signal (as reverse rate (RRI), data request channel or data rate control (DRC), data source channel (DSC), reply (ACK)) is at first separated to be in harmonious proportion and is detected, and the data-signal of emission at BTS 104 by demodulation, deinterleaving and decoding, so that determine the expense and the traffic chips of emission.Be based upon given signal and determine the chip of emission, reconfiguration unit 400 can be based on the contribution of channel knowledge reconstruct to FERAM312.

Can retransmit and by encoder 202 from the packet bit of data source 200, interleaver 204 and/or modulator 206 are treated to a plurality of corresponding " son grouping ", so that be transmitted into base station 104.If base station 104 receives the high s/n ratio signal, then the first sub-grouping can comprise the information that is enough to make base station 104 decodings and derives original packet.For example, can be retransmitted from the grouping of data source 200 and be treated to four son groupings.User terminal 106 sends the first son grouping to the base station 104.It is relatively low that base station 104 can be correctly decoded and derive the probability of original data packet according to the first son grouping that receives.But 104 when receiving second, third and the 4th son grouping and combination from information that the son grouping of each reception is derived in the base station, decodes and the probability of deriving original data packet will increase.As long as correctly carried out original packet to decode (as using Cyclic Redundancy Check or other error detection techniques) in base station 104,, base station 104 stops to send the son grouping thereby just sending answer signal to user terminal 106.User terminal 106 can send the first son grouping of new grouping then.

The reverse link of DO-RevA adopts H-ARQ (Fig. 7), and each 16 time slots grouping here is divided into 4 son groupings and with certain pilotaxitic texture emission, between same two son groupings that interweave 8 time slots is arranged in this pilotaxitic texture.And different user/access terminal 106 can begin emission at different boundary of time slot, so the asynchronous arrival BTS of 4 time slots of different user grouping.Effective design of the interference cancellation receiver of asynchronous effect and H-ARQ and CDMA is described below.

The order of removing signal from FERAM 312 is depended in the gain of interference eliminated.Here the technology of Jie Shiing relate to according to traffic carrying capacity to pilot tone (T2P) ratio, effectively SINR or decoding probability decode (if with CRC by deduct) user.Here disclosed multiple being used for other users from reattempting the method for user's demodulation sign indicating number after FERAM 312 removes.The interference eliminated of BTS FERAM 312 can be implemented effectively to be used for the asynchronous CDMA system, and as EV-DO RevA, the user launches pilot signal, control signal and traffic carrying capacity signal with hybrid ARQ here.The disclosure also can be applied to EV-DV Rel D, W-CDMA EUL and cdma2000.

Traffic carrying capacity interference eliminated (TIC) may be defined as subtraction interference eliminated (subtractiveinterference cancellation), and it removes (Fig. 4) with user data to the contribution of FERAM 312 after the user is correctly decoded.Some and actual cdma system are gone up the relevant practical problems of TIC as CDMA2000, EV-DO, EV-DV and WCDMA and here are resolved.Many these problems are to have asynchronous and fact hybrid ARQ of user by reality system to cause.CDMA2000 even broadening user data frame in time wittingly for example, thus excessive deferral in the backhaul network prevented.The Rel D of the RevA of EV-DO, EV-DV and the EUL of WCDMA also use hybrid ARQ, and this has introduced more than one possible data length.

Multiuser Detection is the main type of the algorithm of TIC application, and Multiuser Detection refers to attempt will have interactive two different users to improve any algorithm of performance by allowing to detect.The TIC method may relate to the mixing of continuous interference eliminated (being also referred to as order interference eliminated or SIC) and parallel interference elimination." continuously interference eliminated " thus refer to decode users successively and use the user data of early decoding to improve any algorithm of performance." parallel interference elimination " broadly refers to the while decode users and deducts the user of all decodings simultaneously.

TIC can eliminate (PIC) with Pilot Interference different.A difference between TIC and the PIC is the pilot tone that signal receiver has been perfectly clear and has been launched in advance.Therefore PIC can only use channel estimating to deduct the contribution of pilot tone to received signals.Second main difference is that reflector and receiver carry out mutual nearly on Traffic Channel by H-ARQ mechanism.Receiver is not known the data sequence of being launched always, up to the user by till the successful decoding.

Similarly, in being called as overhead interference elimination (OIC) technology, hope can be removed overhead channel from front end RAM.Overhead channel all can not be removed before BTS 104 knows the overhead data of emission always, and this forms Overhead and definite then again by decoding.

Interference eliminated has defined class methods continuously.The chain rule of interactive information shows that under ideal conditions interference eliminated can realize the capacity of multiple access access channel continuously.Its essential condition is that all users are frame synchronization, and each subscriber channel can be estimated with insignificant error.

Fig. 5 illustrates the general example of three users' (user 1, and the user 2, and the user 3) distribute power, user's frame emission (frame from all users is received simultaneously) synchronously wherein, and each user launches with identical data rate.Each user is instructed to use specific transmitting power, launches with the power that is substantially equal to noise as user 3; User 2 launches with the power of the power plus noise that is substantially equal to user 3; And user 1 be substantially equal to user 2 add user 3 again the power of plus noise launch.

The order that receiver successively decreases with transmitting power is handled the signal from the user.From k=1 (user's 1 power is the highest), receiver is attempted 1 decoding for the user.If decode successfully, then user 1 contribution to received signal forms and deducts this contribution based on its channel estimating.This can be described as the frame synchronous sequential interference eliminated.Receiver continues, till all users are attempted to decode.Each user has identical SINR after the interference eliminated continuous to the user of previous decoding carried out interference eliminated.

Unfortunately, this method is very responsive for separating code error.If single high-power user fails to be correctly decoded as user 1, then all users' of back Signal to Interference plus Noise Ratio (SINR) can rapid deterioration.This has stoped in all users' decoding after this.Another shortcoming of this method is that the requirement user has specific relative power at the receiver place, and this is difficult to guarantee in fading channel.

Asynchronous and the interference eliminated of frame is as cdma2000

The skew of supposing user's frame is the will and the mistake that intersects each other by the people.This frame asynchronous operation has very big benefit to entire system.For example, the processing power at receiver place will have more consistent real-time service routine file (usage profile) with the network bandwidth.Compare, the frame synchronization among the user can need great processing power and Internet resources suddenly in each frame boundaries end, because all users will finish grouping simultaneously.Asynchronous by frame, BTS 104 can at first the decode user that earliest time arrives rather than the user of maximum power.

Fig. 6 illustrates the example for the even time shift distribution of the equal user's of transmitting power the asynchronous TIC of frame.Fig. 6 has described just to want instantaneous snapshot (snapshot) before decoded at user 1 frame 1.Because frame 0 is decoded and elimination for all users, it is shown Shadowed (user 2 and user 3) to contribution of disturbing.Usually, this method reduces half interference.Half interference was removed by TIC before the frame 1 of decode users 1.

In another embodiment, the user among Fig. 6 can refer to that the user organizes, as the user organize 1, the user organizes 2, the user organizes 3.

Similar if desired data rate, then asynchronous benefit with interference eliminated is relative symmetry between each user with regard to power level and error statistic.In having the general sequence interference eliminated of equal user data rate, last user is with the successful decoding that receive and that depend on all previous users to a great extent of low-down power.

Asynchronous, hybrid ARQ and interweaving is as EV-DO RevA

Fig. 7 illustrates the pilotaxitic texture (as at 1xEV-DO RevA) that is used for RL packet and FL ARQ channel.Each interweave (interweave 1, interweave 2, interweave 3) comprises the section of one group of time interleaving.In this example, each section has 4 time slots long.In each section, user terminal can be to the grouping of base station.Have three to interweave, and each section is that 4 time slots are long.Therefore, between given sub-end of packet that interweaves and the same next son start of packet that interweaves, 8 time slots are arranged.This separates numeral grouping and ACK or negative response (NAK) is relayed to reflector for receiver and has reserved time enough.

Hybrid ARQ utilizes the time-varying characteristics of fading channel.If channel condition is good for preceding 1,2 or 3 son grouping, then can only come the decoded data frame, and receiver sends ACK to reflector with this a little grouping.ACK indication reflector need not send the grouping of residue, but begins new grouping if desired the time.

The receiver architecture of interference eliminated

By TIC, the user's data through decoding is by reconstruct and deduct (Fig. 4), so BTS 104 can remove the interference that the user data through decoding causes other users.The TIC receiver can be furnished with two circulating memory: FERAM 312 and BERAM 316.

FERAM 312 stores the sample (as 2 times of spreading rates) that receives and is that all users are shared.No TIC receiver only uses the FERAM that is approximately 1 to 2 time slot (thereby hold in the demodulating process delay), because do not deduct traffic carrying capacity or overhead interference.In the TIC of the system with H-ARQ receiver, FERAM can stride many time slots, as 40 time slots, and is upgraded by the interference that deducts decode users by TIC.In another configuration, FERAM 312 can have the length of span less than a complete grouping, as has crossed over sub-start of packet from grouping to the length of the time period this grouping sub-end of packet subsequently.

BERAM 316 storages are by the demodulation symbol of the reception bit of demodulator harrow type receiver 314 generations.Each user has different B ERAM, because be by with the despreading of user-specific PN sequence through demodulated symbols, and refer to make up by each RAKE rake and obtains.TIC and no TIC receiver all can use BERAM 316.The demodulation symbol of the son grouping before BERAM 316 is used to store among the TIC, the son before these are not grouped in when FERAM 312 strides all son groupings and no longer are stored among the FERAM 312.BEARAM 316 can be when attempting to decode or time slot upgrade when from FERAM 312, withdrawing from.

Select the method for FERAM length

The big I of BERAM 316 and FERAM 312 is selected according to required processing power, the transfer bandwidth from the memory to the processor, the delay of system and various the trading off between the performance.Usually, use short FERAM 312, the benefit of TIC will be limited, because the longest son grouping of life period will not be updated.On the other hand, demodulation, subtraction and the lower transfer bandwidth of short FERAM 312 meeting generation lesser amts.

Interweave by RevA, the grouping of 16 time slots (four son groupings, each son is grouped in 4 time slots to be launched) will be striden 40 time slots.Therefore, 40 time slot FERAM can be used to guarantee remove the user from all affected time slots.

Fig. 8 illustrates 40 time slot FERAM 312 for EV-DO RevA, and it strides complete 16 time slots grouping.No matter when receive new son grouping, all attempts using all utilized sons that are stored among the FERAM312 this grouping of dividing into groups to decode.If decode successfully, then the contribution meeting of this grouping is by reconstruct with deduct all son grouping members' (1,2,3, or 4) contribution and eliminate from FERAM 312.DO-RevA FERAM length for 4,16,28 and 40 time slots will be striden 1,2,3 or 4 son grouping respectively.The length of the FERAM that implements at the receiver place can be depending on complexity to be considered, supports the different user needs of the time of advent, and the user in the former frame skew is carried out the ability of demodulation sign indicating number again.

Fig. 9 A illustrates the conventional method for the TIC that does not have order interference eliminated (SIC) example that postpones decoding.Other enhancings will be described below.This processing begins to go forward side by side into selection delay feature piece 902 from start block 900.In SIC, select delay feature piece 902 to omit.In functional block 903, BTS 104 finishes to select a user (or one group of user) among the sub user who divides into groups current time slots from those.

In functional block 904, according to user's sequence spreading with upset sequence (scramblingsequence) and according to its constellation sizes, demodulator 304 is for being stored in the sample of some or all the time period demodulation selected user grouping among the FERAM 312.In functional block 906, decoder 308 is attempted to use through the FERAM of demodulation sample and is stored among the BERAM 316 previous demodulated symbols and comes the decode users grouping.

In functional block 910, decoder 308 or another unit can determine whether user's grouping is successfully decoded, promptly by the error checking (errorcheck) such as use cyclic redundancy code (CRC).

If user grouping decoding failure, NAK is accessed terminal 106 to postbacking to give in functional block 918.If user grouping is correctly decoded, then ACK is sent to and accesses terminal 106 in functional block 908, and carries out interference eliminated (IC) in functional block 912-914.According to signal, channel impulse response and sending/receiving filter through decoding, functional block 912 regenerates subscriber signal.Therefore functional block 914 deducts user's contribution from FERAM 312, reduce its interference to the user that also not have to decode.

According to failure and success in the decoding, receiver moves on to the user that the next one will be decoded in functional block 916.When all users having been carried out the trial decoding, new time slot is inserted among the FERAM 312, and next time slot is repeated entire process.Sample can write among the FERAM 312 in real time, and promptly the sample of 2 times of spreading rates can write in each 1/2 chip.

Fig. 9 B illustrates and comprises the equipment of device 930-946 with method among the execution graph 9A.Device 930-946 among Fig. 9 B can hardware, the combination of software or hardware and software realizes.

Select the method for decoding order

Functional block 903 explanation TIC can or be applied sequentially to each user or the parallel user's group that is applied to.Along with group becomes big, the complexity of enforcement can reduce, but the benefit of TIC also may reduce, unless as following iteration (iterate) TIC.

The user be grouped and/or sort according to standard, can change by the type and the available processing power of the speed of channel variation, traffic carrying capacity.Good decoding order can comprise at first and will decode to removing user the most useful and the most probable decoding.Utilize TIC to realize that the standard of maximum gain can comprise:

A. payload size (payload size) and T2P:BTS 104 can divide into groups or the user that sorts according to the payload size, and begin decoding from the user with high transmit power successively, promptly from user with the highest T2P to user with minimum T2P.Decoding and remove high T2P user from FERAM312 has maximum benefit, because these users cause the maximum interference to other users.

B.SINR:BTS 104 can be before the user of the low SINR of decoding the user of the higher SINR of decoding because the user of higher SINR has higher decoding probability.And the user with similar SINR can be grouped into together.In the situation of fading channel, in whole group, when being, SINR becomes, and therefore the SINR that equates can be calculated so that determine suitable ordering.

C. time: BTS 104 can decoding " older " grouping before decoding " newer " grouping (promptly receiving the grouping of more son grouping at BTS 104 places for it).Such selection reflected, for given T2P ratio and ARQ target end, and the imagination that grouping more may divide into groups to decode with each son that increases progressively.

Again attempt the method for decoding

Therefore no matter when the user is correctly decoded, and its interference contribution all deducts from FERAM 312, has just increased the possibility that all users of sharing some time slot are correctly decoded.User's repeated attempt decoding to previous failure is favourable, because their seen interference may significantly reduce.Select delay feature piece 902 to select to be used as the time slot of the reference of decoding and IC (current or pass by).Select user function block 903 will be chosen in the user of terminator grouping in the time slot of selected delay.The selection that postpones can be based on following option:

In case A. all users can be utilized by next time slot among trial decoding and the FERAM 312, then current decoding indication moves to the selection of next (future) time slot.In this case, each user is attempted decoding once in each processing time slot, and this will be corresponding with continuous interference eliminated.

B. iterative decoding is handled in the time slot at each and is all repeatedly attempted decode users.The interference eliminated of user before will benefiting from decoding iteration subsequently for the second time in the iteration through decoding.When a plurality of users were not interfered IC by parallel decoding, iterative decoding can produce gain.By pure iterative decoding on the current time slots, select delay feature piece 902 will repeatedly select same time slot (promptly postponing) simply.

C. oppositely decoding: receiver is separated tune grouping and according to corresponding to all can utilize this grouping of trial solution sign indicating number of transferring of separating of son grouping among the FERAM of certain grouping.Have the grouping (being the user in the present frame skew) of the son grouping that in current time slots, finishes in the trial decoding after, the grouping (that is the user in the former frame skew) that receiver can be attempted to decode and decode in previous time slot and fail.Because the part in the middle of the async user overlaps, the interference of the elimination of the son grouping that finishes in current time slots will improve the chance of decoding son grouping in the past.This process can be by paying a return visit more multi-slot and by iteration.Maximum delay in the forward link ACK/NAK transmission can limit reverse decoding.

D. decode forward: after attempting all groupings with the son grouping that finishes in current time slots are decoded, receiver is attempted up-to-date user is decoded before also can being written among the FERAM in whole son groupings of up-to-date user.For example, 3 that receiver can be in the up-to-date son grouping of 4 time slots of user have been received the back decode users.

Upgrade the method for BERAM

In the BTS of no TIC receiver, grouping is only to decode based on the demodulation symbol that is stored among the BERAM, and FERAM only is used for the user of nearest time period of demodulation.When utilizing TIC, no matter when receiver is attempted the new user of demodulation, and FERAM 312 is still accessed.Yet, when utilizing TIC, the user based on reconstruct with deduct this user contribution and after being correctly decoded, just upgrade FERAM 312.Because complexity considers that hope can be chosen to the FERAM buffer length less than the span of grouping (for example, in EV-DO RevA, requiring 40 time slots to stride the grouping of 16 time slots).Along with new time slot is written among the FERAM 312, they will rewrite the longest sample of life period in the cyclic buffer.Therefore, along with new time slot is received, the time slot that life period is the longest can be rewritten, and decoder 308 will use BERAM 316 for these old times cracks.Even notice that grouping is placed among the FERAM 312 to stator, it is the up-to-date demodulated symbols of this sub-packet memory demodulator (determining according to FERAM 312) that BERAM 316 also can be used for, as interweaving and the intermediate steps of decode procedure.Renewal for BERAM 316 has two main options:

A. based on user's renewal: user's BERAM 316 only with attempt being updated when decoding for this user.In this case, the renewal of older FERAM time slot may be no advantage to given user's BERAM 316, if this user is not suitable time decoder (that is, the FERAM time slot of renewal may slip out from FERAM312 before the tested figure decoding of this user).

B. timeslot-based renewal: in order to utilize the benefit of TIC fully, the BERAM 316 of all affected user can be updated when time slot withdraws from FERAM 312.In this case, the content of BERAM 316 comprises all interference subtraction that FERAM 312 is carried out.

Be used for from eliminating the method for disturbing owing to missing the son grouping that the ACK off period arrives

Usually, the extra process that TIC uses can be incorporated in the decode procedure postponing, when use iterative scheme or backward during scheme (backward shceme) this delay have special correlation.This delay can surpass and ACK sent to transmitter so that the maximum delay when stopping emission that the son relevant with same grouping divide into groups.In this case, divide into groups also to deduct owing to the ACK that loses and to divide into groups at the son of reception soon, utilize the successfully benefit of decoding thereby receiver still can not only deduct son in the past by the data of use through decoding.

By TIC, by reconstruct and deduct, so the interference that it causes other users' groupings can be removed in base station 104 through the user's data of decoding.By H-ARQ, no matter when receive new son grouping, all original packet is attempted decoding.If decode successfully, so for H-ARQ, by reconstruct with deduct branch quantum grouping and the contribution of this grouping can be eliminated from the sample of reception with TIC.Consider according to complexity, can from 1,2,3 or 4 son grouping, eliminate by the longer historical record of storing sample and disturb.Usually, IC can or sequentially be applied to each user, perhaps sequentially is applied to each user's group.

Figure 10 illustrates the receiver sample buffer 312 of 3 time instance: slot time is n time slot, a n+12 time slot and n+24 time slot.For illustrative purposes, Figure 10 illustrates single the interweaving that has from the son grouping of three users in the same vertical shift, thereby emphasizes to have the interference cancellation operation of H-ARQ.Receiver sample buffer 312 is striden all 4 son groupings (for EV-DO RevA, can realize by 40 time slot buffers, because between each 4 time slots grouping 8 time slots are arranged) among Figure 10.Son grouping without decoding has been shown shade.Son through decoding divides into groups to be displayed in the 40 time slot buffers not cover and be eliminated with shade.Each time instance interweaves corresponding to this and goes up the arrival of another height grouping.At slot time n, the grouping of the son of 4 storages of user 1 is correctly decoded, and fails decoded from the up-to-date son grouping of user 2 and 3.

At a time legend n+12 time slot, along with user 1 the interference eliminated through (blank) son grouping 2,3 and 4 of decoding, the continuous son grouping that interweaves arrives.During a time instance n+12 time slot, successfully decode from the grouping of user 2 and 3.

Figure 10 organizes the user in the same vertical shift and uses IC, but does not carry out continuous interference eliminated in this group.In classical group IC, the user in same group does not stand mutual interference eliminated.Therefore,, carry out complexity and reduce, owing to lacking same group inter-user interference elimination and same decoding being attempted causing damage along with the interior number of users change of group is big.Yet by H-ARQ, receiver will arrive all users in the trial solution code character of back in the grouping of each new son, thereby allow that the user realizes mutual interference eliminated in same group.For example, when user 1 the time that is grouped in n, decode, decode when this helps the time that the is grouped in n+12 of user 2 and 3, and then help user 1 when time n+24, to decode.The sub-grouping of all of the grouping of decoding previously can be after them the son grouping be eliminated before decoding reattempting when arriving for other users.Though key point is that the specific user can be always in same group, their son is grouped in can experience the IC gain when other group members decode.

The associating interference eliminated of pilot tone, expense and Traffic Channel

The problem that this joint solves relates to the power system capacity of improving CDMA RL, and this is by estimating effectively at the base station receiver place and eliminating multi-user interference and realize.Usually, RL user's signal is made up of pilot tone, expense and Traffic Channel.This joint has been described all users' joint pilot, expense and traffic carrying capacity IC scheme.

Two aspects have been described here.At first introduce expense IC (OIC).On reverse link, all can disturb other all users' signal from each user's expense.For each user, because the interference that adds up that other all users' expense causes may account for the major part of the suffered total interference of this user.Eliminate this aggregate overhead interference and can further improve systematic function (as for CDMA20001xEV-DO RevA system) and increase reverse chain-circuit capacity, thus performance and capacity that corresponding PIC of surpassing of the systematic function of making and link capacity and TIC realize.

The second, the reciprocation between PIC, OIC and TIC is to illustrate by systematic function and trading off of hardware (HW) design.There are several schemes how to describe to all these three elimination processes and carry out best of breed.Some has the more property gain, and some has higher complexity advantage.For example, described scheme is removed all pilot signals before any expense of decoding and Traffic Channel, decodes successively then and eliminates user's expense and Traffic Channel.

This markingoff pin generally can be applicable to other cdma systems to CDMA20001x EV-DO RevA system, as W-CDMA, and CDMA20001x and CDMA20001x EV-DV.

Eliminate the method for overhead channel

Figure 11 shows the RL overhead channels structure such as EV-DO RevA.Two types overhead channel is arranged: one type is auxiliary RL demodulate/decode, comprises RRI (reverse rate) channel and Auxiliary Pilot Channel (when effective magnitude of load is 3072 bits or uses when bigger); Another kind of type is in order to promote forward link (FL) function, to comprise DRC (data rate control) channel, DSC (data source control) channel and ACK (replying) channel.As shown in figure 11, ACK and DSC channel are based on time slot and carry out time-multiplexed.Ack channel only is launched when with FL the grouping that is transmitted to same user being replied.

In overhead channel, the data of Auxiliary Pilot Channel are just to know in advance to receiver.Therefore, be similar to primary pilot channel, this channel does not need the demodulation sign indicating number, and Auxiliary Pilot Channel can be based on the knowledge reorganization of this channel.The auxiliary pilot of reconstruct can be 2 times of spreading rate resolution and can be expressed as (on a section)

$p_f[2n+{\mathrm{\δ}}_f]=\underset{\mathrm{\μ}=-M}{\overset{M}{\mathrm{\Σ}}}{c}_f[n-\mathrm{\μ}]w_{f,\mathrm{aux}}[n-\mathrm{\μ}]\·G_{\mathrm{aux}}\·\left(h_f\mathrm{\φ}[8\mathrm{\μ}-a_f]\right),n=0,...,511$

$p_f[2n+{\mathrm{\δ}}_f+1]=\underset{\mathrm{\μ}=-M}{\overset{M}{\mathrm{\Σ}}}{c}_f[n-\mathrm{\μ}]w_{f,\mathrm{aux}}[n-\mathrm{\μ}]\·G_{\mathrm{aux}}\·\left(h_f\mathrm{\φ}[8\mathrm{\μ}+4-a_f]\right),n=0,...,511$

The auxiliary pilot signal of equation 1 reconstruct

Wherein n is corresponding to 1 times of chip sample speed, and f is a rake index order (finger number), c _fBe the PN sequence, w _{F, aux}Be to compose the Walsh sign indicating number of giving Auxiliary Pilot Channel, G _AuxBe the gain of the relative dominant pilot of this channel, h _fBe estimated channel coefficient (or channel response), suppose its on a section for constant, φ is that (φ is assumed in [MT for the convolution of receiver low pass filter of filter function or transmitted pulse and 8 times of chip resolution _c, MT _c] in can not ignore), γ _fBe that this rake refers to 8 times of chip time migrations, wherein a of (finger) _f=γ _fMod4, and δ _f[γ _f/ 4].

Second group of overhead channel comprises DRC, DSC and RRI channel, by bi-orthogonal codes or single worker's sign indicating number coding.At receiver end,, at first compare with threshold value through the output of demodulation for each channel.If output below threshold value, is then announced to wipe and do not attempt its reconstruct to this signal.Otherwise they are decoded based on maximum likelihood method (ML) detector of symbol, and this detector can be in the decoder 308 of Fig. 4.Output bit through decoding is used to the reconstruct of respective channel, as shown in Figure 4.The reconstruction signal of these channels provides as follows:

$o_f[2n+{\mathrm{\δ}}_f]=\underset{\mathrm{\μ}=-M}{\overset{M}{\mathrm{\Σ}}}{c}_f[n-\mathrm{\μ}]w_{f,o}[n-\mathrm{\μ}]\·d_o{G}_o\·\left(h_f\mathrm{\φ}[8\mathrm{\μ}-a_f]\right),n=0,...,511$

$o_f[2n+{\mathrm{\δ}}_f+1]=\underset{\mathrm{\μ}=-M}{\overset{M}{\mathrm{\Σ}}}{c}_f[n-\mathrm{\μ}]w_{f,o}[n-\mathrm{\μ}]\·d_o{G}_o\·\left(h_f\mathrm{\φ}[8\mathrm{\μ}+4-a_f]\right),n=0,...,511$

The expense of equation 2 reconstruct (DRC, DSC and RRI) signal

Compare with equation 1, a new d is arranged here _o, it is the overhead channel data, w _{F, o}Be Walsh lid sign indicating number (Walsh cover), G _AuxThe overhead channel gain of representing relative dominant pilot.

The residue overhead channel is 1 bit ACK channel, and it can be the BPSK modulation, uncoded and repeat on half time slot.Receiver can restituted signal and the ack channel data is done hard decision.Reconstruction signal model can be identical with equation 2.

The method of another reconstruct ack channel adopts the accumulation ack signal through demodulation, can be expressed as after normalization:

y＝x+z，

Wherein x is the signal of emission, and z is the noise item of scale, and its variance is σ ²So, the log-likelihood ratio of y (LLR) is shown below:

$L=\ln \frac{\mathrm{Pr}(x=1|y)}{\mathrm{Pr}(x=-1|y)}=\frac{2}{{\mathrm{\σ}}^2}y.$

Then, for the reconstruct purpose, the soft estimation of emission bit can be expressed as:

$\hat{x}=\mathrm{Pr}(x=1)\·1+\mathrm{Pr}(x=-1)\·(-1)=\frac{\exp \left(L\right)-1}{\exp \left(L\right)+1}=\tanh \left(L\right)=\tanh \left(\frac{2}{{\mathrm{\σ}}^2}y\right),$

Here the tanh function expression of can tabulating.The ack signal of reconstruct is very similar to equation 2, exception be with

Replace d ₀Usually, soft estimation and removing method can provide better elimination performance, know data and this method has been brought confidence level because receiver is imprecise.Usually this method may extend into above-mentioned overhead channel.Yet the complexity of maximum a posteriori probability (MAP) detector that is used for obtaining the LLR of each bit can increase with the information bit number exponentially of a code sign.

The mode of an effective implement overhead channel reconstruction is that a rake refers to, can come this signal of bi-directional scaling (scale) according to each relative gain through the overhead signal of decoding, cover them with the Walsh sign indicating number, and they are added to together, then with a PN sequence extension and once filter (channel-scaled filter) the h  by the channel bi-directional scaling carry out filtering.This method can reduce about the computation complexity of subtraction and bandwidth of memory.

Associating PIC, OIC, and TIC

Can carry out associating PIC, thereby OIC and TIC realize high-performance and increase power system capacity.The different decodings of PIC, OIC and TIC and elimination order can produce the different system performance, and hardware design complexity is caused Different Effects.

Carry out PIC earlier, carry out OIC and TIC (first scheme) then together

Figure 12 A illustrates and at first carries out PIC, carries out the method for OIC and TIC then together.In start block 1200, receiver is derived channel estimating for all users and carry out power control in functional block 1202.Because at known all users' in BTS place pilot data, so in case their channel in PIC functional block 1204, estimated then they can be deducted.Therefore, all users' Traffic Channel and some overhead channel stand less interference, and can benefit from the pilot tone elimination of front.

Functional block 1206 is selected the not group G of decode users, and the grouping or the son of decode users are not grouped in the end of current time slots border for these.The demodulation sign indicating number of functional block 1208-1210 executive overhead/Traffic Channel.In functional block 1212, only incite somebody to action the channel data reconstruct of success decoding and from the front end RAM (FERAM) 312 that all users share, deduct these channel datas.Functional block 1214 checks whether have more users to decode.Functional block 1216 finishes this process.

Decoding/reconstruct/elimination can be carried out to the mode of interior next user's of group order from organizing an interior user, and this can be called continuous interference eliminated.With this method, the user of back decoding can have benefited from the elimination of front decode users in same group.The method of simplifying is all users in same group that at first decode, and once deducts their interference contribution then.Second method or scheme (describing below) allow lower bandwidth of memory and more effective pipeline architecture.In two kinds of situations, do not finish but can have benefited from this elimination with the user grouping of this component group crossover at same boundary of time slot.In the asynchronous CDMA system, this elimination can provide main elimination gain.

Figure 12 B illustrates and comprises the equipment of device 1230-1244 with method among the execution graph 12A.Among Figure 12 B device 1230-1244 can hardware, the combination enforcement of software or hardware and software.

Figure 13 A illustrates the variant of method among Figure 12 A.Functional block 1204-1210 removes signal based on the initial channel estimation in the functional block 1202.Functional block 1300 is derived based on the channel estimating of data or meticulous channel estimating.Channel estimating based on data can provide good channel to estimate, and is as described below.Functional block 1302 is carried out remaining PIC, promptly removes the revision estimation of signal based on the fineness of channel estimating in the functional block 1300.

For example, consider that functional block 1204-1210 removes initialize signal and estimates (as pilot signal) P1[n from the sample that receives].Then, based on the better channel estimating of deriving in functional block 1300, this method forms the signal of revising and estimates P2[n].Then, this method is removed the P2[n of increase from the sample that is arranged in RAM 312]-P1[n] poor.

Figure 13 B illustrates and comprises device 1230-1244, and 1310, thus the equipment of the method among the 1312 execution graph 13A.Device 1230-1244 among Figure 13 B 1310,1312 can hardware, the combination of software or hardware and software carries out.

At first carry out PIC, carry out OIC then, carry out TIC (alternative plan) more then

Alternative plan is similar to above-mentioned Figure 12 A, the overhead channel that difference is same group of user before any Traffic Channel is by the demodulation sign indicating number by the demodulation sign indicating number.This scheme is suitable for not having the system that interweaves, because there is not the restriction of strictness the ACK time limit.For interlacing system, as DO Rev.A, because the grouping of ACK/NAK signal response Traffic Channel, the patient decoding delay of Traffic Channel grouping generally is limited in a pair of time slot (a couple slots) (1 time slot=1.67ms).Therefore, if some overhead channels spread surpasses this time range, then this scheme becomes infeasible.Especially, for DO RevA, Auxiliary Pilot Channel and ack channel are short-duration format and can be deducted before TIC.

Joint pilot/overhead/traffic channel is eliminated (third party's case)

Figure 14 A illustrates the method for carrying out associating PIC, OIC and TIC.After start block 1400, receiver is derived channel estimating for all users and is carried out power control in functional block 1402.Functional block 1404 is selected the not group G of decode users.Functional block 1406 reappraises (re-estimate) channel according to pilot tone.Functional block 1408-1410 attempts executive overhead/Traffic Channel demodulation sign indicating number.Functional block 1412 is carried out PIC for all users, and only carries out OIC and TIC for the user who has the channel data of successfully being decoded.

Being different from above-mentioned first scheme (Figure 12 A), carry out channel estimating (functional block 1402) for all users after, is not to deduct pilot tone immediately from FERAM 312, and as no IC scheme, channel estimating is used to power control.Then, for the user's group that finishes on same packet/subpacket border, this method is to give definite sequence execution sequence decoding (functional block 1408 and 1410).

For the user who attempts decoding, this method at first reappraises channel (functional block 1402) according to pilot tone.The pilot tone of comparing is power control and separated timing (functional block 1402), and this pilot tone stands less interference, because be eliminated with the interference of the grouping intersected early decoding grouping that changes of traffic carrying capacity to be decoded.Therefore, the channel estimating quality is improved, and this is all useful to business channel decoding and elimination performance.This new channel estimating is used to business channel decoding (functional block 1410), and some overhead channel decoding (functional block 1408) (as RRI channel among the EV-DO).In case in functional block 1412 is that a user finishes decode procedure, this method will deduct this user's interference contribution from FERAM 312, and this comprises user's pilot channel and any overhead/traffic channel through decoding.

Whether functional block 1414 checks have more users to decode.Functional block 1416 finishes this process.

Figure 14 B illustrates and comprises the equipment of device 1420-1436 with method among the execution graph 14A.Device 1420-1436 among Figure 14 B can hardware, the combination of software or hardware and software is implemented.

Figure 15 A illustrates the variant of method among Figure 14 A.Functional block 1500 is derived the channel estimating based on data.Functional block 1502 is carried out residue PIC arbitrarily, and is such as shown in FIG. 13A.

Figure 15 B illustrates and comprises device 1420-1436,1510,1512 equipment with method among the execution graph 15A.Device 1420-1436 among Figure 15 B 1510,1512 can hardware, the combination of software or hardware and software implements.

First and third party's case between compromise (tradeoff)

Seem that first scheme has the performance that is better than third party's case because know pilot signal at the BTS place, and its to cancel them in front be significant.Have identical elimination quality if suppose two schemes, then first scheme can surpass third party's case on all data rates.Yet for first scheme, because pilot channel estimation is higher than the interference that traffic data demodulation stands, the estimation channel coefficients noise used for the purpose (pilot tone and overhead/traffic) of reconstruct is higher.Yet, for third party's case, because pilot channel estimation just carried out before traffic data demodulation/decoding once more, so this meticulous interference level that channel estimating stood and traffic data demodulation is identical.Therefore, generally speaking, elimination mass ratio first scheme of third party's case is good.

From the angle of hardware designs, third party's case can have following advantage: this method can be sued for peace and they are eliminated together to pilot tone with through the expense and the traffic channel data of decoding, and therefore, this method has been saved bandwidth of memory.On the other hand, reappraising of pilot tone can be carried out (from this angle of memory read sampling) with overhead channel demodulation or Traffic Channel demodulation, and therefore the requirement of bandwidth of memory do not increased.

Be 80% or 90% of third party's case if suppose the elimination quality of first scheme, then exist every user data rate trading off between a large number of users gain.Usually, if all users are in low data rate district then tend to first scheme, if all users are in the high data rate district then opposite.This method also can reappraise channel according to Traffic Channel when the data of a grouping in a single day are decoded.Eliminating quality will improve, because compare with pilot channel, Traffic Channel is worked with the SNR of high (many).

In case overhead channel is by successful demodulation, then they can be removed (elimination), in case and Traffic Channel by successful demodulation sign indicating number, then they can be removed.The base station is possible in some time point success all expense that access terminal of demodulate/decode and Traffic Channel.If (PIC, OIC TIC) take place, and then FERAM will only comprise remaining interference and noise for this.Pilot tone, expense and traffic channel data can different order be eliminated, and are the subclass elimination that accesses terminal.

A kind of approach is once to be that a user carries out interference eliminated (any combination of PIC, TIC and OIC) from RAM 312.Another kind of approach is that (a) is one group of user signal (any combination of PIC, TIC and OIC) of accumulating reconstruct and (b) is this group execution interference eliminated at synchronization then.These two kinds of approach can be applicable to any method disclosed herein, scheme and process.

For interference eliminated improves channel estimating

But the systematic function of the ability appreciable impact CDMA receiver of sample that accurately reconstruct receives, this CDMA receiver by reconstruct and remove launch data various compositions implement interference eliminated.In the RAKE receiver, on the reasonable time section, carry out pilot filtering (i.e. accumulation) then and estimate multipath channel by carry out the PN despreading with relative pilot frequency sequence.The length of pilot filtering is normally selected according to following such compromise, and promptly multisample increases estimation SNR by accumulating more, does not accumulate the long time simultaneously so that estimate that SNR is owing to the time fluctuation of channel worsens.The channel estimating of pilot filter output is used to carry out data demodulates then.

As described in Figure 4, a practical methods of implementing interference eliminated in the CDMA receiver is the contribution of 1 times of stream of chips of a plurality of emissions of reconstruct to (as 2 times of chips) FERAM sample.This relates to the stream of chips of definite emission and the estimation of the total channel between transmitter chips and the receiver sample.Because the channel estimating that the RAKE rake refers to is represented multipath channel self, total channel estimates also to illustrate the existence of reflector and receiver filtering.

This section has disclosed several technology of improving the total channel estimation for interference eliminated in the CDMA receiver.These technology can be applicable to CDMA2000,1xEV-DO, 1xEV-DV, WCDMA.

In order to carry out the TIC of the grouping that is correctly decoded, among Fig. 4 receiver can be from decoder output information extraction bit and by coding again, interweave modulation again, application data channel gain and expansion and the stream of chips of reconstruct emission more again.In order to be that TIC estimate to receive sample with pilot channel estimation, ask transmitter code laminar flow and convolution with the mould of the channel estimating of the reflector filtering of pilot PN sequence despreading and receiver filtering and RAKE receiver.

For replacing the use of pilot channel estimation, can be by the channel estimating (referring to delay place) of coming despreading to be improved with the data chips self of reconstruct at each RAKE rake.The channel estimating of Gai Shaning is useless for the data demodulates of grouping like this, because grouping is correctly decoded, but the channel estimating of this improvement is used for the contribution of this grouping of reconstruct to front-end samples.By this technology, each that refers to (as 8 times of chip resolution) for RAKE rake postpones, and this method can be come the sample (being inserted to 8 times of chips as interior) of " despreading " reception with the stream of data chips of reconstruct, and accumulates on the reasonable time section.This will cause the channel estimating improved, because Traffic Channel is (this traffic carrying capacity is the function of data rate to channel T2P ratio) with the power emission higher than pilot channel.Use data chips to estimate that as TIC channel can be the higher-wattage user and produces more precise channels estimation, this higher-wattage user eliminates most important to high accuracy.

For replacing referring to postpone to estimate multipath channel that this section has been described channel estimation process at each RAKE rake, this channel estimation process will be estimated the combined effect of transmitter filter, multipath channel and receiver filter clearly.This estimation can have the identical resolution of front-end samples (2 times of chip FERAM) with over-sampling.Channel estimating can realize by the transmit data chips despreading front-end samples with reconstruct, thus the T2P gain that realizes having precision of channel estimation.The time span of the channel estimating that evenly separates can be selected based on the information that refers to about RAKE rake postpone with to the prior estimate of the array response of transmitter filter and receiver filter.And, the channel estimating that the information that refers to from the RAKE rake can be used to become more meticulous and evenly separates.

Figure 16 illustrates the model of emission system, and it has emission filter p (t), overall/composite channel h (t) (to the multipath channel g (t) that describes below) and receiver filter q (t).The digital baseband of radio communication channel is represented can L discrete multipath composition modeling

$g\left(t\right)=\underset{l=1}{\overset{L}{\mathrm{\Σ}}}{a}_l\mathrm{\δ}(t-{\mathrm{\τ}}_l)$ Equation 3

Wherein the pahtfinder hard amplitude is to have phase delay τ ₁A ₁Reflector filtering and receiver filtering effect of Combination may be defined as  (t), wherein

Equation 4

Wherein

The expression convolution.Combination  (t) is selected to the raised cosine response similar usually.For example, in CDMA2000 and deriving technology thereof, this response is similar to the example  (t) shown in Figure 17.Total channel is estimated to be provided by following formula

$\hat{h}\left(t\right)=g\left(t\right)\⊗\mathrm{\φ}\left(t\right)=\underset{l=1}{\overset{L}{\mathrm{\Σ}}}{a}_l\mathrm{\φ}(t-{\mathrm{\τ}}_l)$ Equation 5

Figure 18 A and 18B illustrate the example (real part and imaginary part) of harrowing the channel estimating of the multipath channel of estimating at each RAKE rake place of finger in referring to based on three RAKE.In this example, actual channel illustrates with solid line, and a ₁Provide by asterisk.Reconstruct (dotted line) is based on a in the top equation 3 ₁Realize.Among Figure 18 A and the 18B RAKE rake refer to channel estimating be based on the pilot chip despreading realize (total here pilot tone SNR is-24dB).

Refer to postpone with the data chips of regeneration but not pilot chip is come despreading at RAKE rake

The quality of channel estimating has direct influence to the fidelity of reconstruct user contribution to received signal.In order to improve the performance of the cdma system of implementing interference eliminated, can determine the channel estimating of improvement with user's data chips through reconstruct.This will improve the precision that interference deducts.Relative with typical " about the despreading of user's pilot transmitted chip ", a kind of technology that is used for cdma system can be described as " about the data chips despreading of user's emission ".

Among Figure 18 A-18B RAKE rake refer to channel estimating be based on the pilot chip despreading (total here pilot tone SNR for-24dB).The channel estimating of the improvement that refers to based on RAKE rake is shown Figure 19 A-19B and with the example of data chips despreading, data chips is with the power emission than the high 10dB of pilot chip here.

Figure 20 A is illustrated in RAKE rake and refers to postpone the method for carrying out despreading with the data chips of regeneration.In functional block 2000, harrow type receiver 314 (Fig. 4) thus obtaining the RAKE rake with Pilot PN chip despreading front-end samples refers to value.In functional block 2002, demodulator 304 is carried out data demodulates.In functional block 2004, decoder 308 is carried out data decode and check (CRC).In functional block 2006, if CRC passes through, then unit 400 is by the data chips of encoding, interweaving, modulating and emission is determined in expansion again.In functional block 2008, thereby unit 400 obtains the channel estimating that each rake refers to the improvement of delay place with the data chips despreading front-end samples of launching.In functional block 2010, unit 400 is with the contribution to front-end samples of the channel estimating reconstruct subscriber traffic that improves and expense.

Thereby Figure 20 B illustrates the equipment of the method that comprises device 2020-2030 execution graph 20A.Device 2020-2030 among Figure 20 B can hardware, the combination of software or hardware and software realizes.

Estimate the compound channel of FERAM resolution with the data chips of regeneration

Typical case CDMA receiver can estimate that multipath channel refers to the complex value that postpones at each RAKE rake.Receiver front end before the RAKE receiver can comprise low pass receiver filter (that is, q (t)), and itself and transmitter filter (that is p (t)) are mated.Therefore, for the receiver of the filter of realizing mating with channel output, the RAKE receiver self attempts only to mate multipath channel (that is g (t)).The delay that RAKE rake refers to usually in minimum separation requires (as, each rake refers to separate at least 1 chip) from independently time tracking ring (time-tracking loop) driving.Yet physics multipath channel self can have energy usually in plurality of continuous postpones.Therefore, a kind of method is estimated compound channel (that is h (t)) with the resolution of front-end samples (as, 2 times of chip FERAM).

By the control of the transmitting power on the CDMA reverse link, the jointed harrow of all multipaths and receiver antenna refers to that SNR is controlled in the particular range usually.This SNR scope can cause estimating that from the compound channel that despread pilot chips is derived this pilot chip has big relatively estimate variance.Here it is why the RAKE receiver attempt only will harrow and refer to that " peak value " that be set in the energy delay profile locate.But by the T2P advantage with the data chips despreading of reconstruct, compound channel estimates to cause the estimation comparison to h (t) better with the direct estimation of the g (t) of the die combination of  (t).

Channel estimation process described herein has obviously been estimated the combined effect of transmitter filter, multipath channel and receiver filter.This estimation can be identical with the resolution of the front-end samples of over-sampling (as, 2 times of FERAM).Channel estimating can realize by the transmit data chips despreading front-end samples with reconstruct, thereby realizes the T2P gain with precision of channel estimation.The time span of (uniformly spaced) channel estimating that evenly separates can be selected based on the information that refers to about RAKE rake postpone with to the prior estimate of the array response of reflector and receiver filter.And, the channel estimating that the information that the RAKE rake refers to can be used for becoming more meticulous and evenly separates.Note, estimate that the technology of compound channel self also is useful, because it does not require the prior estimate of design use  (t).

Figure 21 A, 21B illustrate the example that the sample that evenly separates that uses 2 times of chip resolution is estimated compound channel.At Figure 21 A, among the 21B, data chips SNR is-4dB, corresponding to-the pilot tone SNR of 24dB and the T2P of 20dB.With only refer to that at RAKE rake the position compares with the data chips despreading, uniform (uniform) channel estimating provides better quality.At high SNR place, the effect limits of " fat path (fatpath) " refer to the ability of the accurate reconstruct channel in position with RAKE rake.The uniform sampling approach is particularly useful when estimating that SNR is high, estimates that SNR is high corresponding with the situation that with data chips is high T2P despreading.For the specific user, when T2P is high, channel reconstruction fidelity will be very important.

Figure 22 A illustrates the method for regenerated data chips with the compound channel of (uniform) resolution estimation uniformly of utilizing.Functional block 2000-2006 and 2010 is similar to above-mentioned Figure 20 A.In functional block 2200, RAKE receiver 314 (Fig. 4) or another parts refer to that based on the RAKE rake delay determines time span for uniform reconstruct.In functional block 2202, demodulator 304 or another parts are the channel estimating that the reasonable time span is determined improvement by the data chips despreading front-end samples with uniform delay emission.

Figure 22 B illustrates and comprises device 2020-2030, the equipment of method among 2220,2222 the execution graph 22A.Device 2020-2030 among Figure 22 B can hardware, the combination of software or hardware and software is implemented.

In the superincumbent description, g (t) is a wireless multipath channel self, and h (t) comprises the convolution of wireless multipath channel and reflector and receiver filtering: h (t)=g (t) and phi (t).

In the superincumbent description, " sample " can be speed (as twice of every chip sample) arbitrarily, but " data chips " is one of every chip.

Shown in functional block 2006 among Figure 20 A, " data chips of regeneration " is by coding again, interweave again, again modulation and again despreading form, as mentioned above.In principle, " regeneration " is the processing that the analog information bit is located to live through at mobile transmitter (accessing terminal)

" reconstructed sample " expression be stored in FERAM 312 or with receiver in FERAM 312 sample in the memory (as twice of every chip sample) independently.The sample of these reconstruct by with (regeneration) transmit data chips and channel estimating mutually convolution form.

If forming transmit data chips again or forming under the situation that receives sample then speech " reconstruct " and " regeneration " commutative use again.Sample or chip can form again, because " chip " waits operation to form by coding more again, yet " sample " is based on the chip that use forms again and incorporates the influence of wireless channel (channel estimating) and reflector and receiver filtering into and formed.Speech " reconstruct " and " regeneration " all mean basically to be rebuild or forms.And there is not technical difference.An embodiment uses " regeneration " for data chips, uses " reconstruct " for sample.Receiver can have data chip regeneration unit and sample reconstruction unit so.

Transmit subchannel gains is suitable certainly on the reverse link of the cdma system that interference eliminated is arranged Answer (adaptation)

Multi-user interference is a kind of limiting factor in the CDMA emission system, and any receiver technology that can alleviate this interference can significantly improve attainable data throughout.This section is described and to be used for adjusting the technology of transmit subchannel gains that (adapt) has the system of IC.

In reverse link transmissions, each user launches pilot tone, expense and service signal.Pilot tone provides the synchronization and the estimation of send channel.For MAC and traffic carrying capacity decode structures (set-up), overhead subchannel (such as RRI, DRC, DSC and ACK) is necessary.Pilot tone, expense and traffic sub channel have different requirements to Signal to Interference plus Noise Ratio (SINR).In cdma system, single power control can be adjusted the transmitting power of pilot tone, and the fixed gain that the power of expense and traffic sub channel has relative pilot tone.When BTS was equipped with PIC, OIC and TIC, a plurality of subchannels stood the interference of varying level, and interference level depends on the order of IC and the ability of elimination.In this case, the static relation between the subchannel gains may be damaged the performance of system.

This section is described the new gain control strategy for Different Logic subchannel in the system that implements IC.This technology as EV-DO RevA, and can be applied to EV-DV RelD, W-CDMA EUL, and cdma2000 based on cdma system.

Described technology is by implementing power and the gain controlling on the different subchannels according to the gain of each subchannel of performance self-adapting ground change of measuring, the performance of this measurement is with packet error rate, and SINR or interference power are weighed.Purpose provides reliable power and gain control mechanism, the effect that this mechanism allows to make full use of IC simultaneously for the time variation the loose transmission of subchannel robustness is provided.

Interference eliminated refers to remove the contribution of these subchannels to front-end samples after the logical sub-channel decoding, so that reduce the interference to other signals that will decode subsequently.In PIC, BTS knows the pilot transmitted signal, and the pilot tone channel estimating reconstruct that receives.In TIC or OIC, interference is to come this reception subchannel of reconstruct to remove by the reception subchannel that is used in the decoding of BTS place.

Current BTS (not having IC) control pilot subchannel E _CpPower so that satisfy error rate requirement in the Traffic Channel.It is relevant that the power of traffic sub channel and pilot tone multiply by immobilisation factor T2P, and this is decided by PT Payload Type and final target end (target termination goal).The self adaptation of pilot power (adaption) is to realize by the closed power controlling mechanism that comprises interior ring and outer shroud.Interior ring is intended to the SINR (E with pilot tone _Cp/ Nt) remain on threshold level T, and the exterior ring power control example as, (PER) changes threshold level T based on packet error rate.

When carrying out IC at the receiver place (Fig. 4), the self adaptation of subchannel gains is useful for system.In fact, because each subchannel all stands the interference of varying level, they should be by corresponding adjustment so that provide the performance of expectation for the gain of pilot tone.This section can solve the gain controlling problem to expense and pilot subchannel, and has described the adaptive technology of T2P, and by making full use of IC, the T2P self adaptation has increased the throughput of system.

Has the important parameter in the system of IC

Two adjustable parameters are that overhead subchannel gain and traffic carrying capacity gain to pilot tone (T2P).When TIC was effective, overhead subchannel gain can be increased (not having TIC relatively), so that allow between pilot tone and the overhead performance more compromise.By the baseline G that represents with G to use in the current system, the new value of overhead channel gain will be provided by following formula:

G’＝G·Δ _G。

In no IC scheme, the interference level that the overhead/pilots subchannel stands is identical with Traffic Channel, and the T2P/G of certain ratio can be expense and Traffic Channel performance and pilot channel estimation and provides satisfied performance.When IC was used, the interference level of overhead/pilots and traffic carrying capacity was different, and T2P can reduce so that allow the relevant performance of two class subchannels.For given payload, this method can allow the relative list value of T2P with factor _T2PReduce, so that meet the demands.By the baseline T2P that represents that with T2P payload specific in the current system is used, then the new value of T2P is:

T2P’＝T2P·Δ _T2P

The parameter Δ _T2PBut quantum turn to one group of finite value or centrifugal pump (as-0.1dB to-1.0dB) and be sent to and access terminal 106.

Can keep controlled certain tittle is traffic carrying capacity PER, pilot tone SINR and hot noise increase (rise over thermal).Pilot tone SINR can not fall below the required minimum level of channel estimating.Hot noise increase (ROT) is very important for the stability and the link budget of the CDMA reverse link of guaranteeing power control.In no TIC receiver, ROT defines for received signal.Usually, thus ROT should remain on and allows the compromise of good capacity/covering radius in the preset range.

Hold the control of noise recruitment

I ₀The signal power of expression receiver input.From the signal that receives, eliminate to disturb and make power reduction.I ₀' be illustrated in the average power signal of the input end of demodulator 304 after the IC:

I ₀’≤I ₀。

After upgrading with IC, I ₀' the available front-end samples of value measure.When IC was performed, ROT was still important for overhead subchannel, and ROT answers relative threshold to control, promptly in order to guarantee

$\mathrm{ROT}=\frac{I_0}{{\mathrm{<figure-callout\; id="0"\; label="N"\; filenames="A20058004857600461.png,A20058004857600611.png"\; state="\{\{state\}\}">N</figure-callout>}}_0}<{\mathrm{ROT}}_{\mathrm{thr}},$

N wherein ₀It is noise power.

Yet traffic carrying capacity and some overhead subchannel are also benefited from IC.The decoding performance of these subchannels is relevant with the hot noise increase of measuring behind IC.Effectively ROT is the ratio of signal power and noise power behind the IC.Effectively ROT can be by threshold value control, that is,

${\mathrm{ROT}}_{\mathrm{eff}}=\frac{{I_0}^{\&prime;}}{{\mathrm{<figure-callout\; id="0"\; label="N"\; filenames="A20058004857600461.png,A20058004857600611.png"\; state="\{\{state\}\}">N</figure-callout>}}_0}<{\mathrm{ROT}}_{\mathrm{thr}}^{\left(\mathrm{eff}\right)}$

Supposing under the constant situation of noise level, ROT _EffRestriction can be expressed as I of equal valuely ₀' restriction:

$I_o^{\&prime;}\&le;I_o^{\left(\mathrm{thr}\right)}$

I wherein ₀ ^(thr)Be corresponding to ROT _Thr ^(eff)The signal power threshold value.

Fixing overhead gain techniques

When ROT increased, the SINR of pilot tone and overhead channel (it does not benefit from IC) reduced, and may cause wiping speed increases.In order to compensate this influence, can improve overhead channel gain by fixed value or by adapting to specific system condition.

The fixing technology of the relative pilot tone of gain of overhead subchannel has been described.The technology that is proposed is adjusted the level and the Δ of (adapt) pilot subchannel for each user _T2P

Fixing Δ _GThe closed-loop control of the T2P of=0dB

Figure 23 illustrates for E _CpAnd Δ _T2PReach fixedly Δ _GThe closed power control (functional block 2308) of=0dB.For Δ _T2PAnd E _CpAdaptive first solution comprise:

A. for E _CpSelf adaptation, interior and outer shroud 2300,2302 can be carried out power control in a conventional manner.Outer shroud 2300 receiving targets (target) PER and traffic carrying capacity PER.Interior ring 2304 receive threshold T 2302 and the pilot tone SINR that measures also export E _Cp

B. closed loop gain control (GC) 2306 adjusts Δ based on the measurement to the interference of removing _T2PThe ROT that gain controlling 2306 receptions are measured and the ROTeff of measurement also export Δ _T2PReceiver is measured the interference of being removed by the IC scheme and is regulated Δ _T2P

C. Δ _T2PCan be periodically send to all receiving terminals 106 in the sector with message.

For Δ _T2PAdaptation, if the interference behind the IC is from I ₀Be reduced to I ₀', then therefore the amount of T2P can reduce:

${\mathrm{\&Delta;}}_{T2P}=\frac{I_0^{\&prime;}}{I_0}\&ap;\frac{{\mathrm{ROT}}_{\mathrm{eff}}}{\mathrm{ROT}}.$

E _Cp(by PC ring 2304) increased, is shown below:

${E_{\mathrm{cp}}}^{\&prime;}=\frac{I_0}{I_0^{\left(\mathrm{thr}\right)}}{E}_{\mathrm{cp}}..$

The ratio that has the total transmitting power of system of IC and do not have between the total transmitting power of system of IC will be expressed as:

$C=\frac{E_{\mathrm{cp}}(1+G+T2P)}{{E_{\mathrm{cp}}}^{\&prime;}(1+G+T2P^{\&prime;})},$

Here G is an overhead channel gain.For big value T2P (G relatively), ratio C can be approximately:

$C\&ap;\frac{I_0^{\left(\mathrm{thr}\right)}}{{I_0}^{\&prime;}}.$

Estimate that for effective ROT effectively ROT changes fast owing to the change of PC and channel condition.But Δ _T2PReflected ROT _EffSlow change.Therefore, for Δ _T2PSelection, effectively ROT is the average window measurement of length by signal behind the IC.Average window can be at least power two double-lengths of control update cycle.

Fixing Δ _GThe closed-loop control of the T2P of＞0dB

Except effective ROT of gain controlling 2306 receive thresholds and Δ _G＞0dB (functional block 2400), Figure 24 is identical with Figure 23.Δ _T2PAdaptive replaceable method is based on has identical coverage radius of cell to IC with no IC system requirements.In two kinds of situations, E _CpDistribution is identical.The effect of IC is double for the system of full and down: the 1) signal power before the IC, I ₀, the signal power of not having the IC system is relatively increased; 2) because the closed power of PER control is controlled I ₀' will be tending towards similar to the signal power of no IC system.Δ _T2PAdjust as follows:

${\mathrm{\&Delta;}}_{T2P}=\frac{I_0^{\left(\mathrm{thr}\right)}}{{I_0}^{\&prime;}}\&ap;\frac{{\mathrm{ROT}}_{\mathrm{thr}}^{\left(\mathrm{eff}\right)}}{{\mathrm{ROT}}_{\mathrm{eff}}}$

△ based on ACK _T2PControl

Figure 25 illustrates the E based on the ACK subchannel with fixed overhead subchannel gain (functional block 2506) _CpAnd Δ _T2PPC.

Δ _T2PClosed loop GC require feedback signal from BTS to AT, here all AT receive from BTS to Δ _T2PSame broadcast value (broadcast value).Interchangeable solution is with Δ _T2PThe open loop GC2510 and the closed loop PC 2500,2504 of each pilot tone do the basis.Closed loop pilot PC comprises according to threshold value T _o2502 adjust E _CpInterior ring 2504.Outer shroud control 2500 speed of wiping by overhead subchannel are wiped the speed guide as data rate controlled (DRC) subchannel error probability or DRC.No matter when DRC wipes speed surpasses threshold value, T _oAll increase, when threshold value is following, reduce gradually but wipe speed at DRC.

Δ _T2PAdjust by the ACK forward subchannel.Especially, by measuring the statistical value of ACK and NACK, AT is evaluated at the traffic carrying capacity PER (functional block 2508) at BTS place.The PER of gain controlling 2510 comparison object traffic carrying capacity PER and measurement.When PER is higher than threshold value, Δ _T2PIncrease, reach the T2P baseline value of no IC system up to T2P '.On the other hand, for lower PER, Δ _T2PReduce to handle so that make full use of IC.

Variable overhead gain techniques

Further optimization to transceiver can be by adjusting Δ _T2PAnd overhead subchannel gain (G expense) makes it all adapt to IC to handle and realize.In this case, need extra feedback signal.Δ _GValue can be from 0dB to the 0.5dB quantization.

Except expense GC 2600, Figure 26 is similar to Figure 24.The method 2600 of a kind of GC of overhead subchannel is based on the signal power of measuring behind the IC.In this case, E _CpBe used so that provide identical coverage radius of cell for no IC system.Signal before the IC has the power I of increase ₀, and overhead gain can compensate the interference that increases.Following such adjustment overhead gain is pressed in this enforcement:

${\mathrm{\&Delta;}}_G=\frac{I_0}{I_0^{\left(\mathrm{thr}\right)}}\&ap;\frac{\mathrm{ROT}}{{\mathrm{ROT}}_{\mathrm{thr}}}$

Δ _GCan be controlled so as to and be not less than 0dB, because this is corresponding to the unlikely useful overhead subchannel power that reduces.

Gain and power control scheme can comprise for E _CpInterior ring and outer shroud PC 2304,2300, as shown in figure 23, the aforesaid Δ that is used for _G GC ring 2600, be used for Δ _T2POpen loop GC2306, no matter when PER is at the above Δ of desired value here _T2PAll increase, and when target is following, all reduce as PER.The Δ of maximum horizontal _T2PAllow, it is corresponding to the level of no IC receiver.

Only carry out the overhead gain control of DRC

Figure 27 illustrates the variant of Figure 26, wherein has the overhead gain control 2702 of only carrying out DRC.

Even the overhead subchannel gain self adaptation, Δ _T2PGain controlling 2700 can carry out with closed loop, as mentioned above.In this case, E _CpAnd Δ _T2PBe Controlled, as the scheme among Figure 23, the self adaptation of overhead subchannel gain 2702 is wiped the speed execution by DRC simultaneously.Especially, if DRC wipes on threshold value, overhead subchannel gain 2702 increases.When DRC wipes speed under threshold value the time, overhead gain 2702 reduces gradually.

T2P control in the multicell network of many sectors

Because Δ _T2PGC on cell level, carry out, AT 106 can realize softer soft handover, different sectors can produce different self adaptation (adaption) request.In this case, can be for being requested to be sent to the Δ of AT _T2PSelection consider different options.On cell level, the amount that a kind of method can select the T2P minimum to reduce in the item that ask the sector of full and down, promptly.

${\mathrm{\&Delta;}}_{T2P}^{\left(\mathrm{cell}\right)}=\underset{s\&Element;\left\{\mathrm{loaded}\sec \mathrm{tors}\right\}}{\max }\left\{{\mathrm{\&Delta;}}_{T2P}^{\left(s\right)}\right\}$

△ wherein _T2P ^(s)It is the Δ that sector s requires _T2PΔ T can receive the difference request from different districts, and in this case, can adopt a plurality of standards.A kind of method can be selected the Δ corresponding to serving sector (serving sector) _T2PSo that guarantee and its most reliable communication.

In order to select Δ in sub-district and AT place _T2P, also can consider other selections, comprise minimum value, maximum or mean value in the value of being asked.

For the mobile terminal, an importance is to use T2P '=T2P * Δ _T2P, and G '=G * Δ _G, Δ wherein _T2PBe based on I at the BTS place _oAnd I _o' measured value (also may be about I _o ^ThrKnowledge) calculate and Δ _GAlso calculate at BTS.Because these delta factors calculate at BTS, so they can be broadcast to accessing terminal that all correspondingly work by each BTS.

Here the notion of Jie Shiing can be applied to the WCDMA system, and the WCDMA system uses overhead channel, as the Dedicated Physical Control Channel (E-DPCCH) or the High-Speed Dedicated Physical Control Channel (HS-DPCCH) of Dedicated Physical Control Channel (DPCCH), enhancing.The WCDMA system can use Dedicated Physical Data Channel (E-DPDCH) form of Dedicated Physical Data Channel (DPDCH) form and/or enhancing.

Here the content that is disclosed can be applied to have two the different interleaving structures WCDMA system of (for example 2-ms Transmission Time Interval and 10-ms Transmission Time Interval).Therefore, front-end memory, demodulator is with the configurable one or more son groupings of striding the grouping with different Transmission Time Interval of subtracter.

For TIC, business datum can be by one or more users with at least a transmission in EV-DO Release 0 form or the EV-DO Revision A form.

Specific decoding order as described herein can be corresponding to the order of demodulation sign indicating number.Decoded packet should come from demodulation more again, because the process of carrying out demodulation from the grouping of FERAM 312 is converted into better decoder input with interference eliminated.

Those skilled in the art will appreciate that and to use a lot of different technologies and in the technology any one to represent performance information and signal.For example, the data of mentioning in the above-mentioned explanation, instruction, order, information, signal, bit, symbol, and chip can be expressed as by voltage, electric current, electromagnetic wave, magnetic field or magnetic particle, light field or light particle or above combination and show.

Those skilled in the art can also further recognize, in conjunction with various illustrative logical blocks functional blocks, module, circuit and the algorithm steps that embodiment disclosed herein describes, can realize with electronic hardware, computer software or the combination of the two.For the interchangeability of hardware and software clearly is described, in the above description usually according to property assembly, functional block, module, circuit and the step of having described various examples with functional term.This function still is that hardware mode is carried out realization with software actually, depends on the specific application and the design constraint of whole system.The professional and technical personnel can use distinct methods to realize described function to each specific should being used for, but this realization decision should not be considered to exceed scope of the present invention.

Various exemplary logical block functional block, module and the circuit of describing in conjunction with embodiment disclosed herein can be with general processor, digital signal processor (DSP), application-specific integrated circuit (ASIC) (ASIC), field programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components or the above combination in any that is designed to carry out function described herein realize or carry out.General processor can be a microprocessor, but replacedly, processor also can be processor, controller, microcontroller or the state machine of any routine.Processor also may be implemented as the combination of computing equipment, for example, and the combination of the combination of DSP and microprocessor, the combination of a plurality of microprocessors, one or more microprocessor and a DSP core or other this type of configuration arbitrarily.

Can directly implement in conjunction with the method for embodiment description disclosed herein or the step of algorithm with hardware, the software module of processor execution or the combination of the two.Software module can place the storage medium of any other form known in RAM memory, flash memory, ROM memory, eprom memory, eeprom memory, register, hard disk, removable hard disk, CD-ROM or the technical field.Storage medium can be connected to processor, so that processor can be from read information and to the storage medium writing information.Replacedly, storage medium can be integrated in the processor.Processor and storage medium can place ASIC.ASIC can place user terminal.Replacedly, processor and storage medium can be used as separated components and place in the user terminal.

Here included title is for reference and some chapters and sections of assist location.These titles are not in order to limit the wherein scope of described notion, and these notions also have applicability in other chapters and sections of whole specification.

To the above-mentioned explanation of the disclosed embodiments, make those skilled in the art can realize or use the present invention.Multiple modification to these embodiment will be conspicuous to one skilled in the art, and defined herein general basic principle can be applied to other embodiment under the situation that does not break away from the spirit or scope of the present invention.Therefore, the present invention will can not be restricted to these embodiment shown in this article, but will meet and principle disclosed herein and novel features characteristics the wideest consistent scope.

Claims (34)

1. method, it comprises:

Reception is from the sample of the signal of a plurality of emissions that access terminal, and this sample comprises pilot channel data, overhead channel data and traffic channel data;

In the described pilot channel data of reconstruct, overhead channel data and the traffic channel data at least one;

In described sample, at least one at least a portion in the pilot channel data after the described reconstruct, overhead channel data and the traffic channel data is eliminated;

Handle the business datum of described sample to obtain to access terminal and send by first;

In the gross power of measurement traffic carrying capacity packet error rate (PER), pilot tone Signal to Interference plus Noise Ratio (SINR) and signal at least one; And

According in measured traffic carrying capacity packet error rate, pilot tone SINR and the gross power at least one, in described pilot tone, expense and the Traffic Channel at least one power and at least one in the gain control.

2. the method for claim 1, wherein said signal comprises code division multiple access (CDMA) signal.

3. the method for claim 1 also comprises:

With described reception sample storage in buffer; With

In pilot channel data, overhead channel data and the traffic channel data from the reception sample of described storage after the described reconstruct of elimination at least one.

4. the method for claim 1, wherein said overhead channel comprise reverse rate (RRI) channel, Auxiliary Pilot Channel, request of data control (DRC) channel, data source control (DSC) channel and reply in (ACK) channel at least one.

5. the method for claim 1, wherein said overhead channel comprise Dedicated Physical Control Channel (DPCCH), the Dedicated Physical Control Channel (E-DPCCH) that strengthens and at least one in the High-Speed Dedicated Physical Control Channel (HS-DPCCH).

6. the method for claim 1, wherein said overhead channel comprises Auxiliary Pilot Channel, this method also comprises based on the described Auxiliary Pilot Channel of channel estimating reconstruct.

7. the method for claim 1, the pilot channel data of wherein eliminating after the reconstruct comprises:

Be described a plurality of definite channel estimating that access terminal;

Use described channel estimating to come the reconstruct pilot channel data; And

Pilot channel data from the sample that accesses terminal from all after the described reconstruct of elimination.

8. the method for claim 1, the overhead channel data of wherein eliminating after the reconstruct comprise:

Be described a plurality of definite channel estimating that access terminal;

Use described channel estimating to come reconstruct overhead channel data; And

Overhead channel data from the sample that accesses terminal from all after the described reconstruct of elimination.

9. the method for claim 1, the data channel signal of wherein eliminating after the reconstruct comprises:

Be described a plurality of definite channel estimating that access terminal;

Use described channel estimating to come the reconstruct data channel data; And

Data channel signal from the sample that accesses terminal from all after the described reconstruct of elimination.

10. the method for claim 1, at least one that wherein control in described power and the described gain comprises:

When being eliminated, traffic channel data increases overhead channel gain.

11. the method for claim 1, at least one that wherein control in described power and the described gain comprises:

Reduce at least one traffic carrying capacity that accesses terminal to pilot tone (T2P) ratio.

12. the method for claim 1, at least one that wherein control in described power and the described gain comprises:

The value of relative threshold control hot noise increase (ROT).

13. the method for claim 1, at least one that wherein control in described power and the described gain comprises:

The closed loop pilot channel power controlling mechanism of ring and outer shroud in use has.

14. method as claimed in claim 13, wherein said outer shroud compares described traffic carrying capacity packet error rate of measuring and target service amount packet error rate.

15. method as claimed in claim 13, wherein said outer shroud is wiped speed with the target of measuring of wiping speed and described overhead channel of overhead channel and is compared.

16. method as claimed in claim 15, wherein said overhead channel are data rate control (DRC) channels.

17. method as claimed in claim 15, wherein said overhead channel comprise the Dedicated Physical Control Channel (E-DPCCH) of enhancing.

18. method as claimed in claim 15, wherein said overhead channel comprise Dedicated Physical Control Channel (DPCCH).

19. the method for claim 1, at least one that wherein control in described power and the described gain comprises:

After in eliminating described pilot tone, expense and traffic data channel at least one, measured signal power; With

Use closed loop gain control to come to adjust the change of traffic carrying capacity to pilot tone (T2P) ratio based on the signal power of measuring after eliminating.

20. method as claimed in claim 19, also comprising periodically accesses terminal to send at least one has the message of traffic carrying capacity to the change through adjusting of pilot tone (T2P) ratio.

21. method as claimed in claim 19, the change of wherein said T2P ratio is adjusted by replying (ACK) forward channel.

22. the method for claim 1, at least one that wherein control in described power and the described gain comprises:

With the value of the effective hot noise increase of average window measurement (ROT), the length of described average window is power two double-lengths of control update cycle at least.

23. the method for claim 1, at least one that wherein control in described power and the described gain comprises:

Traffic carrying capacity is to the open-loop gain control and the control of closed loop pilot power of pilot tone (T2P) ratio.

24. method as claimed in claim 23, wherein said closed power control comprises the interior ring of adjusting described pilot power according to threshold value.

25. method as claimed in claim 24 also comprises:

When data rate control (DRC) is wiped speed above second threshold value, increase described threshold value; And

When DRC wipes speed less than described second threshold value, reduce described threshold value.

26. the method for claim 1 also comprises:

When surpassing threshold value, the described traffic carrying capacity packet error rate of measuring increases the change of traffic carrying capacity to pilot tone (T2P) ratio; And

Reduce the change of traffic carrying capacity during less than described threshold value in the described traffic carrying capacity packet error rate of measuring to pilot tone (T2P) ratio.

27. the method for claim 1 also comprises:

Gross power according to described at least one traffic carrying capacity packet error rate of measuring, pilot tone Signal to Interference plus Noise Ratio (SINR) and signal is adjusted overhead channel gain.

28. method as claimed in claim 27 is wherein adjusted overhead channel gain and is comprised that the value of the hot noise increase that will measure and the value of target hot noise increase compare.

29. method as claimed in claim 27 is wherein adjusted overhead channel gain and is comprised that the data rate control (DRC) that will measure wipes speed and target data rate control (DRC) and wipe speed and compare.

30. the method for claim 1 also comprises:

Send a plurality of orders from a plurality of sectors to accessing terminal, each request all requires described accessing terminal to reduce traffic carrying capacity to pilot tone (T2P) ratio;

In a plurality of requests of the sector of carrying, identify the reduce minimum request of traffic carrying capacity to pilot tone (T2P) ratio from fullcharging.

31. method as claimed in claim 30 also comprises the sector that the identification fullcharging carries.

32. the method for claim 1 also comprises:

Send a plurality of requests from a plurality of sectors to accessing terminal, each request all requires described accessing terminal to reduce traffic carrying capacity to pilot tone (T2P) ratio;

From a plurality of requests, identify and the described request that accesses terminal and be associated from serving sector.

33. the method for claim 1, at least one that wherein control in described power and the described gain comprises:

Control the gain of described expense and Traffic Channel.

34. a base station, it comprises:

Memory, it is configured to store the data sample from the signal of a plurality of receptions that access terminal, and described sample comprises pilot channel data, overhead channel data and traffic channel data;

Demodulator, it is configured to one or more demodulation overhead channel data and traffic channel datas of accessing terminal;

Decoder, it is configured to overhead channel data and traffic channel data through demodulation are decoded, and determines which overhead channel data and traffic channel data are correctly decoded;

Reconfiguration unit, it is configured to overhead channel data and the traffic channel data reconstruct overhead channel data and the traffic channel data of decoding correctly, and described reconfiguration unit also is configured to use described channel estimating reconstruct pilot channel data;

Subtracter, it is configured to deduct in the sample from be stored in described memory the pilot channel data of reconstruct, the overhead channel data of reconstruct and the traffic channel data of reconstruct;

Power control unit, after its traffic channel data that is configured to the overhead channel data of pilot channel data, reconstruct in described reconstruct and reconstruct is deducted in the sample from be stored in described memory, control the pilot channel power that at least one accesses terminal; And

Gain control unit, it is configured to based on the change to pilot tone (T2P) ratio of the Interference Control traffic carrying capacity of described elimination of measuring.

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