WO2006105689A1 - Methode et dispositif de reduction de la complexite du traitement des signaux des terminaux mobiles - Google Patents

Methode et dispositif de reduction de la complexite du traitement des signaux des terminaux mobiles Download PDF

Info

Publication number
WO2006105689A1
WO2006105689A1 PCT/CN2005/000455 CN2005000455W WO2006105689A1 WO 2006105689 A1 WO2006105689 A1 WO 2006105689A1 CN 2005000455 W CN2005000455 W CN 2005000455W WO 2006105689 A1 WO2006105689 A1 WO 2006105689A1
Authority
WO
WIPO (PCT)
Prior art keywords
channel
mobile terminal
signal
base station
complexity
Prior art date
Application number
PCT/CN2005/000455
Other languages
English (en)
Chinese (zh)
Inventor
Baiqing Zong
Changchun Xiao
Original Assignee
Zte Corporation
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Zte Corporation filed Critical Zte Corporation
Priority to PCT/CN2005/000455 priority Critical patent/WO2006105689A1/fr
Publication of WO2006105689A1 publication Critical patent/WO2006105689A1/fr

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B17/00—Monitoring; Testing
    • H04B17/20—Monitoring; Testing of receivers
    • H04B17/24—Monitoring; Testing of receivers with feedback of measurements to the transmitter

Definitions

  • the present invention relates to wireless communications, and more particularly to a method and apparatus for reducing the complexity of signal processing of mobile terminals without degrading the quality of data transmission. Background technique
  • EDGE Enhanced Data Rates for GSM Evolution
  • HSDPA High Speed Down-Link Packet Access
  • the receive equalizer algorithm must be able to cope with multipath equal power signals received in a 16 ⁇ delta interval.
  • 16 ⁇ 8 in the GSM system within approximately 5 bit duration, if the Viterbi algorithm MLSE (Maximum Likelihood Sequence Estimation) is employed, computational complexity is 250, but in the EDGE system is 15 bits, if still using the MLSE
  • the Viterbi algorithm whose computational complexity will be exponentially increasing, ie 2 15 , is difficult to implement in the system. Therefore, for systems with advanced modulation, only suboptimal equalizer designs can be considered.
  • sub-ideal equalizers for advanced modulation are still exponentially increasing. Due to the scalability of the base station system, these sub-ideal equalizers (such as a hardware-accelerated RSSE disclosed in EP 1 432 190) are generally not a problem in base stations. However, implementation in a mobile terminal is a problem because the development direction of the mobile terminal is dexterous and multi-functional. On the one hand, the reduction in volume limits the processing capability of the mobile terminal, and on the other hand, the multi-function requires the mobile terminal to have Large enough processing power. In this way, a complex equalizer occupies a large amount of processor resources, which is bound to seriously affect the application development of the mobile terminal. Summary of the invention
  • the technical problem to be solved by the present invention is to provide a method and apparatus for reducing the complexity of signal processing of a mobile terminal without degrading the transmission quality of data, and reducing the complexity of signal processing of the mobile terminal for a sub-ideal equalizer of advanced modulation. To the extent that the development direction of mobile terminals is dexterous and multifunctional.
  • the present invention provides a method for reducing the complexity of signal processing of a mobile terminal, wherein a channel compensator is arranged on the base station side, and a downlink signal transmitted by the base station is convoluted by the channel compensator to cancel the signal. Distortion of the signal caused by the wireless channel during transmission, and the parameters of the channel compensator are obtained by inferring the channel parameters after estimation.
  • the foregoing method for reducing the complexity of signal processing of a mobile terminal is characterized in that, in the TDD mode, the following steps are specifically included:
  • Step al adding a training sequence to the uplink signal
  • Step a2 The uplink signal is received by the base station after being transmitted through the wireless channel, sampled by down-conversion, and the training sequence is located from the sampled signal;
  • Step a3 The base station obtains channel parameters by estimating the uplink channel, and simultaneously equalizes and demodulates the received signal;
  • Step a4 performing inverse transform processing on the channel parameters, and the base station transmitter uses the obtained value as a downlink channel compensator parameter;
  • Step 5 • The channel compensator convolves the pulse-formed signal in the downstream direction, and then transmits it after up-conversion.
  • the method for reducing the complexity of the signal processing of the mobile terminal further includes the following steps: Step a6 : The mobile terminal receives the pre-compensated signal and performs down-conversion, sampling, receive filtering, demodulation, and decoding de-interleaving.
  • the above method for reducing the complexity of signal processing of a mobile terminal is described.
  • the channel compensator is a laterally limited impulse response structure.
  • Step M In the initial state, the base station sends a downlink signal that is not compensated, and adds a training sequence to the transmitted data. ;
  • Step b2 The mobile terminal performs down-conversion, sampling, and filtering on the received signal, and locates The position of the training sequence in the received signal;
  • Step b3 The mobile terminal estimates and inverts the downlink channel to obtain a channel compensation correction amount caused by the channel change, and reports the correction amount to the base station;
  • Step b4 The base station side updates the channel compensator parameters
  • Step b5 In the next transmission cycle, the pulse-formed signal in the downlink direction is subjected to convolution processing using the updated channel compensator parameters and then transmitted.
  • the method for reducing the complexity of signal processing of the mobile terminal further includes the following steps: Step b6: The mobile terminal performs down-conversion, sampling, reception filtering, demodulation, decoding and de-interleaving after receiving the pre-compensated signal.
  • the method for reducing the complexity of the signal processing of the mobile terminal is as described above.
  • the mobile terminal reports the obtained channel compensation correction amount to the base station through the control channel.
  • the above method for reducing the complexity of signal processing of a mobile terminal is as described above.
  • the control channel is an independent dedicated control channel or a fast auxiliary control channel.
  • the step b3 specifically includes: Step b31: setting a storage unit to store a first delay positioning number whose initial value is 0; Step b32: Obtaining a channel according to the training sequence The channel compensation correction amount caused by the change; Step b33: determining whether the channel compensation correction amount is 0, if not 0 enters the next step, if it is 0, then proceeds to step b35;
  • Step b34 reporting the channel compensation correction amount by the independent dedicated control channel or the fast auxiliary control channel, and proceeding to step b4;
  • Step b35 Performing an operation of multiplying 2 by 1 after delaying the number of positioning, and re-assigning the obtained value to the first delayed positioning number to obtain a second delayed positioning number;
  • Step b36 Delay the second delay to locate a number of frames and return to step b32.
  • the present invention further provides a device for reducing the complexity of signal processing of a mobile terminal, which includes a channel compensator disposed on a base station side, where the channel compensator performs downlink signals sent by the base station. Convolution processing to cancel the distortion of the signal generated by the wireless channel during signal transmission, and the parameters of the channel compensator are obtained by inferring the channel parameters after estimation.
  • the above apparatus for reducing the complexity of signal processing of a mobile terminal, wherein the mobile terminal communicates with a base station by time division duplexing or frequency division duplexing.
  • the invention realizes no equalization or reduced rank equalization reception of the mobile terminal, and greatly reduces the letter of the mobile terminal
  • the complexity of the processing, especially for mobile communication systems using advanced modulation or the like, can effectively save the processor resources of the mobile terminal and facilitate its application development.
  • the radio signal transmitted by the downlink is pre-compensated by the base station side, and the pre-compensation pre-processing of the downlink signal by the base station transmitter is dynamically adaptively adjusted according to the feedback of the channel parameter by the base station receiver or the mobile terminal.
  • the base station receiver directly feeds back the parameters of the uplink channel to the base station transmitter pre-compensator, and then the base station transmitter can fully compensate the downlink channel transmission distortion so that the training sequence or character of the auxiliary channel equalization in the downlink direction can be used for the service. Transmission, effectively improve the downlink data transmission capability.
  • the mobile terminal calculates the channel state change amount according to the downlink training sequence sent by the base station, and then reports the channel state change amount to the base station through the uplink control channel, and the base station adjusts and updates the channel compensator according to the reported change amount, and the whole process is performed. It is an iterative process that greatly reduces the complexity of signal processing for mobile terminals.
  • FIG. 1 is a block diagram of a base transceiver and a mobile terminal transceiver in a TDD mode according to the present invention
  • FIG. 2 is a structural diagram of a downlink channel compensator of a base station transmitter according to the present invention
  • FIG. 3 is a block diagram of a base station and a mobile terminal transceiver in the FDD mode according to the present invention
  • FIG. 4 is a flow chart of the mobile terminal changing the time window variable time window update algorithm in the FDD mode according to the present invention.
  • the invention pre-compensates the transmitted downlink wireless signal by the base station side to cancel the distortion of the signal generated by the wireless channel during the signal transmission process, so that the mobile terminal can receive the high-quality signal, thereby reducing the complexity of the signal processing of the mobile terminal.
  • the compensation pre-processing of the downlink signal by the base station transmitter is dynamically adaptively adjusted according to the feedback of the channel parameters by the base station receiver or the mobile terminal.
  • the present invention will be described below for the two modes of Time Division Duplexing (TDD) and Frequency Division Duplexing (FDD).
  • the base station can completely obtain the parameters of the downlink channel by performing channel processing on the uplink signal, and pre-processing the downlink signal according to the channel parameters to implement unbalanced reception of the mobile terminal, thereby simplifying physical layer signal processing of the mobile terminal.
  • the training sequence or characters for the auxiliary channel equalization can be used for service transmission, thereby effectively improving the downlink data transmission capability.
  • FIG. 1 is a block diagram of a base station and a mobile terminal transceiver in a TDD mode according to the present invention.
  • the transmission path of the mobile terminal is still the same as the current transmitter structure, that is, the data to be transmitted first is performed.
  • the signal is transmitted by the antenna after the amplifier.
  • the uplink signal processing is received by the base station after the radio frequency signal is transmitted through the wireless channel, sampled by down-conversion, and after receiving the filter, the received training sequence s R is located from the sampled signal, and the base station passes the uplink.
  • the channel estimation is obtained by the adaptive equalizer, and the equalization process is performed at the same time, and the function of transmitting the uplink channel parameters to the transmitter after inverse processing of the channel parameters is added.
  • the base station adds a channel compensator with a tap coefficient c ⁇ after the pulse shaping filter to pre-compensate the transmitted signal.
  • the mobile terminal After receiving the signal pre-compensated by the base station, the mobile terminal passes through the down-conversion, sampling and receiving filters, and does not need to equalize and directly demodulate the baseband data, so that the complexity of the receiver and the processing capacity are greatly simplified.
  • the channel compensator can adopt a horizontal finite impulse response FIR (Finite Impulse Response) structure, as shown in Fig. 2.
  • FIR Finite Impulse Response
  • the FIR in Figure 2 is 2N+1, ie
  • Precompensation of the downlink transmit signal requires first obtaining the parameters of the compensator based on the current transport channel state.
  • the tap coefficient C of the channel compensator is obtained by receiving the training sequence in the uplink data. Let the modulated training sequence be, e is the signal error, then
  • a training sequence is added to the uplink signal;
  • the uplink signal is received by the base station after being transmitted through the wireless channel, and is sampled after down-conversion;
  • the received training sequence is located from the sampled signal; and the channel parameter C is obtained through the training sequence, Equalizing and demodulating the received signal;
  • the base station obtains channel parameters by estimating the uplink channel, performs inverse transform processing, and feeds back the obtained value to the base station transmitter as a downlink channel compensator parameter;
  • the channel compensator performs convolution processing on the pulse-formed signal in the downlink direction, and then transmits the signal after up-conversion;
  • the mobile terminal performs down-conversion, sampling, reception filtering and demodulation after receiving the pre-compensated signal. Since the signal has been pre-compensated by the transmission, the signal can be directly demodulated, which simplifies the complexity of the receiver and the amount of processing.
  • the uplink and downlink signal transmissions use different frequencies, so the transmission channel characteristics of the uplink and downlink signals are different.
  • the compensation for the downlink channel is performed by the base station and the mobile terminal together.
  • the mobile terminal first calculates the channel state change amount according to the downlink training sequence sent by the base station; and then reports the channel state change amount to the base station through the uplink; the base station adjusts and updates the channel compensator according to the reported change amount.
  • the whole process is an iterative process.
  • Figure 3 is a block diagram of a base transceiver and a mobile terminal transceiver in FDD mode.
  • the structure of the base transceiver station in the FDD mode is basically the same as that in Fig. 2, except that the transmission of the channel parameters to the base station transmitter is mainly performed by the mobile terminal.
  • the equalizer processes only the amount of change in the downlink channel parameters and is a process of gradually decreasing the rank until the base station transmitter completely compensates for the distortion of the downlink channel.
  • the output of the mobile terminal receiving filter end at time tl is:
  • the estimated value of the downlink channel parameters by the mobile terminal is actually a correction value that the base station transmitter does not fully compensate for the downlink channel.
  • the wireless channel is generally a time-varying channel
  • AC is generally not zero and is time-varying, but AC is generally characterized by low-order filters (because At- is much smaller than the fading period of the channel, that is, at the time scale of At The upper channel is a slow time varying channel). Therefore, the pre-compensation of the downlink channel by the base station transmitter greatly simplifies the equalizer of the mobile terminal, thereby effectively saving the processor resources of the mobile terminal.
  • the base station transmits a downlink signal that has not been compensated in the initial state, and adds a training sequence to the transmitted data.
  • the channel compensator can take the following values:
  • the mobile terminal down-converts, samples and filters the received RF signal, locates the position of the training sequence in the received signal, and estimates and inverts the downlink channel.
  • the channel compensation correction due to channel variation is obtained by the LMS algorithm.
  • the obtained channel compensation correction Ac is transmitted to the base station through an uplink dedicated control channel (SDCCH) or a fast auxiliary control channel (FACCH).
  • SDCCH uplink dedicated control channel
  • FACCH fast auxiliary control channel
  • the base station side updates the channel compensator.
  • the relationship between the old and new parameters of the compensator is given by:
  • the pulse-formed signal in the downlink direction is convoluted and transmitted after using the updated channel compensator parameters.
  • the mobile terminal performs down-conversion, sampling, reception filtering, and demodulation after receiving the pre-compensated signal. Since the signal has been pre-compensated by the transmission, the signal can be directly demodulated without equalization, but still Downlink estimation and monitoring of the downlink channel is required.
  • the present invention solves this problem using a variable time window update algorithm.
  • Figure 4 is a flow chart of the variable time window update algorithm for the downlink channel parameters of the mobile terminal in FDD mode.
  • the mobile terminal determines the downlink channel parameter update based on the estimation of the channel parameter correction amount AC. If the AC is not equal to zero, the mobile terminal reports the estimated value of the downlink channel parameter correction amount ⁇ C every frame period. If AC is equal to zero, the mobile terminal directly demodulates the received data, and delays one frame to continue to estimate the downlink channel parameter correction amount. If the AC is still zero, the delay three frames continue to correct the downlink channel parameter. Make an estimate, and so on, until AC is not equal to zero. As shown in Figure 4, it includes the following steps:
  • Step 41 Initialize the delay positioning number m, set to 0;
  • Step 42 Estimating the channel parameter correction value AC
  • Step 43 Determine whether ⁇ (3 is 0, if it is not 0, go to the next step, if it is 0, go to step 45;
  • Step 44 Reporting AC by SDCCH or FACCH channel, and performing equalization processing on the data;
  • Step 45 Performing 2m+l operation on m and assigning it to m;
  • Step 46 After delaying m frames, return to step 42;
  • the invention realizes the unbalanced or reduced rank equalization reception of the mobile terminal, and greatly reduces the signal processing complexity of the mobile terminal, especially for the mobile communication system adopting advanced modulation, which can effectively save the processor resources of the mobile terminal and facilitate the application development thereof.
  • the present invention pre-compensates the downlink transmitted wireless signal by the base station side, and the base station transmitter compensates the downlink signal for the dynamic adaptive adjustment according to the feedback of the channel parameter by the base station receiver or the mobile terminal.
  • the base station receiver directly feeds back the parameters of the uplink channel to the base station transmitter pre-compensator, and then the base station transmitter can fully compensate for the downlink channel transmission distortion, so that the training sequence or the character of the auxiliary channel equalization in the downlink direction can be used.
  • the mobile terminal calculates the channel state change amount according to the downlink training sequence sent by the base station, and then reports the channel state change amount to the base station through the uplink control channel, and the base station adjusts and updates the channel compensator according to the reported change amount, the whole process. It is an iterative process.

Landscapes

  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Mobile Radio Communication Systems (AREA)

Abstract

La présente invention concerne une méthode et un dispositif permettant de réduire la complexité du traitement des signaux des terminaux mobiles. La station de base est équipée d’un compensateur de canal, dont la convolution permet de traiter le signal descendant transmis par la station de base et de compenser ainsi la distorsion engendrée par le canal sans fil. Les paramètres du compensateur de canal sont définis en fonction d’une évaluation des paramètres du canal. La présente invention permet de pré-compenser le signal sans fil descendant, mais également d’ajuster la pré-compensation de manière dynamique et adaptée en fonction du signal retour relatif aux paramètres du canal transmis par la station de base ou le mobile. Ce dernier peut donc recevoir des signaux non égalisés ou peu égalisés. Cette méthode permet ensuite de réduire de manière significative la complexité du traitement des signaux du mobile, en particulier pour les systèmes de communication mobile à modulation élevée, tout en économisant les ressources du processeur du terminal mobile.
PCT/CN2005/000455 2005-04-07 2005-04-07 Methode et dispositif de reduction de la complexite du traitement des signaux des terminaux mobiles WO2006105689A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
PCT/CN2005/000455 WO2006105689A1 (fr) 2005-04-07 2005-04-07 Methode et dispositif de reduction de la complexite du traitement des signaux des terminaux mobiles

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/CN2005/000455 WO2006105689A1 (fr) 2005-04-07 2005-04-07 Methode et dispositif de reduction de la complexite du traitement des signaux des terminaux mobiles

Publications (1)

Publication Number Publication Date
WO2006105689A1 true WO2006105689A1 (fr) 2006-10-12

Family

ID=37073079

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2005/000455 WO2006105689A1 (fr) 2005-04-07 2005-04-07 Methode et dispositif de reduction de la complexite du traitement des signaux des terminaux mobiles

Country Status (1)

Country Link
WO (1) WO2006105689A1 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2013174351A3 (fr) * 2012-08-28 2014-01-16 中兴通讯股份有限公司 Procédé et dispositif de formation de faisceau

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1464660A (zh) * 2002-06-19 2003-12-31 上海贝尔有限公司 一种宽带码分多址指示信道接收器
CN1496158A (zh) * 2002-08-01 2004-05-12 ���ǵ�����ʽ���� 用于检测业务信道和导频信道之间的功率比的设备和方法
CN1534910A (zh) * 2003-03-27 2004-10-06 �͵ø��ƶ�ͨ�Źɷ����޹�˾ 正交频分复用无线通信系统与信道补偿方法

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1464660A (zh) * 2002-06-19 2003-12-31 上海贝尔有限公司 一种宽带码分多址指示信道接收器
CN1496158A (zh) * 2002-08-01 2004-05-12 ���ǵ�����ʽ���� 用于检测业务信道和导频信道之间的功率比的设备和方法
CN1534910A (zh) * 2003-03-27 2004-10-06 �͵ø��ƶ�ͨ�Źɷ����޹�˾ 正交频分复用无线通信系统与信道补偿方法

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2013174351A3 (fr) * 2012-08-28 2014-01-16 中兴通讯股份有限公司 Procédé et dispositif de formation de faisceau
CN103634037A (zh) * 2012-08-28 2014-03-12 中兴通讯股份有限公司 波束成形方法及装置
CN103634037B (zh) * 2012-08-28 2020-01-14 中兴通讯股份有限公司 波束成形方法及装置

Similar Documents

Publication Publication Date Title
KR100935378B1 (ko) 이중 안테나 무선 기기를 위한 주파수 도메인 등화기
US8861575B2 (en) Method and apparatus for equalizing signals
US8073088B2 (en) Method and communication device for interference cancellation in a cellular TDMA communication system
US6792049B1 (en) Digital transceiver system with adaptive channel pre-coding in an asymmetrical communications network
US7684481B2 (en) High speed data packet access minimum mean squared equalization with direct matrix inversion training
EP1903732A2 (fr) Détermination au domaine fréquentielle de coefficients d'égalisateur pour radio MIMO/MISO
EP1903729A2 (fr) Égalisateur de domaine de fréquence avec annulation d'interférences dominantes pour radio à antenne double
WO2008115702A1 (fr) Égaliseur adaptatif destiné à des canaux de communication
JPWO2010029765A1 (ja) 無線送信装置およびプレコーディング方法
US7957463B2 (en) Adaptive frequency equalizer
JP2005323384A (ja) 線形フィルタ等化器
TW201121254A (en) Transceivers and methods for enhancing channel estimation
WO2013059350A1 (fr) Annulation avancée d'interférences pour un réseau geran (réseau d'accès radio gsm/edge) précodé
WO2011108429A1 (fr) Circuit d'estimation de canal, procédé d'estimation de canal, et récepteur
JP2000040987A (ja) 無線通信システム
KR20070110325A (ko) 채널 이퀄라이제이션을 위한 방법 및 시스템
US10862715B2 (en) Equalizer and method for equalizing a receive signal
WO2001048991A1 (fr) Correcteur de phase avec une fonction cout prenant en compte l'energie de bruit
JPH0795655A (ja) 移動通信システム
Sahoo et al. Channel equalization using adaptive zero forcing technique in rayleigh fading channel
EP1629649A1 (fr) Appareil et procede pour le precodage d'un signal de multiporteuse
WO2006105689A1 (fr) Methode et dispositif de reduction de la complexite du traitement des signaux des terminaux mobiles
Gibbard et al. Asymmetric signal processing for indoor wireless LANs
JP2002344362A (ja) 等化装置、受信装置、及び等化方法並びに受信方法
JP4559205B2 (ja) 無線通信システム

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application
WWE Wipo information: entry into national phase

Ref document number: 200580048760.9

Country of ref document: CN

NENP Non-entry into the national phase

Ref country code: DE

WWW Wipo information: withdrawn in national office

Country of ref document: DE

NENP Non-entry into the national phase

Ref country code: RU

WWW Wipo information: withdrawn in national office

Country of ref document: RU

122 Ep: pct application non-entry in european phase

Ref document number: 05741843

Country of ref document: EP

Kind code of ref document: A1

WWW Wipo information: withdrawn in national office

Ref document number: 5741843

Country of ref document: EP