CN1549473B - Beam forming method adapted to wide band CDMA system - Google Patents
Beam forming method adapted to wide band CDMA system Download PDFInfo
- Publication number
- CN1549473B CN1549473B CN031154158A CN03115415A CN1549473B CN 1549473 B CN1549473 B CN 1549473B CN 031154158 A CN031154158 A CN 031154158A CN 03115415 A CN03115415 A CN 03115415A CN 1549473 B CN1549473 B CN 1549473B
- Authority
- CN
- China
- Prior art keywords
- module
- signal
- weights
- wave beam
- input
- Prior art date
- Legal status (The legal status 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 status listed.)
- Expired - Fee Related
Links
Images
Landscapes
- Radio Transmission System (AREA)
- Mobile Radio Communication Systems (AREA)
Abstract
The present invention relates to a beam forming method applicable in wide-band code-division multiple access system, which comprises the steps of carrying out the spatial processing on array signals, wherein the array signals are baseband signals X aligned in time delay; during the pilot bit period of a first time slot, performing the cross-correlation operation on a symbol obtained through respreading and scrambling a known pilot symbol in an uplink channel for each frame as a reference signal and the baseband signals X, so as to obtain a cross-correlation matrix r*r=E[Xr*]; calculating a suboptimum weighted value till all pilot bits in the first time slot are over; during the periods of information symbol bits and other time slots, performing the iteration operation on the suboptimum weighted value as an initial value, the respread and scrambled signals of despread and descrambled information symbol bits and the respread and scrambled signals of known pilot bits as reference signals respectively, based on the principle of the minimum mean square error, so as to figure out a self-adaptive suboptimal weighted value W=r*r; and forming beams by means of the suboptimal weighted value W to obtain Y=W*X. The beam forming method simplifies the structure of the system and also greatly reduces the technical difficulty and the amount of calculation.
Description
Technical field
The present invention relates to broadband CDMA system, particularly relate to a kind of adaptive beam formation method of intelligent antenna base station.
Background technology
WCDMA WCDMA is a third generation mechanics of communication, because of its with preceding two generation mechanics of communication compare, have better confidentiality, higher performances such as transmission rate, so become the communication system development current.Because code division multiple access system is an interference-limited systems, the existence that multiple access disturbs can have a strong impact on systematic function, therefore how effectively to suppress the key that multiple access interference (MAI) is 3G (Third Generation) Moblie research.Utilize the difference of useful signal and the interference signal aspects such as propagation characteristic on signal structure, room and time, what propose at present mainly contains two kinds of multi-access interference suppression technology: intelligent radio and Multiuser Detection.And intelligent antenna technology is the key technology of WCDMA system, it help to anti-interference, increase power system capacity and increase the sub-district area coverage.Smart antenna has two kinds of implementations at present: adaptive mode and switched-beam mode, though theoretically in the engineering practice realization of adaptive antenna all than the switched-beam antenna complex many, but adaptive antenna can obtain more performance.In the adaptive mode; Respective antenna weights or perhaps beam shape can be adjusted arbitrarily according to certain space-time two-dimensional adaptive algorithm; Thereby current transmission environment is carried out the maximum possible coupling, and corresponding smart antenna received beam can be to point to arbitrarily, can make maximum sensing of wave beam aim at desired user like this; Aim at interference user, obtain higher processing gain and zero of wave beam is fallen into.And each weights can only be selected from pre-specified several class values in switched-beam; The smart antenna mode of operation in a certain moment can only be selected from pre-designed several wave beams; Not to point to arbitrarily; Thereby only possibly carry out the part coupling to current transmission environment, say from point of theory not to be optimum.
Therefore; Most crucial technology is exactly that adaptive beam forms technology in the antenna system, and antenna system depends primarily on the performance of adaptive beam formation method to the improvement degree of communication system, has proposed various adaptive beam formation method at present; Like constant modulus algorithm; But this algorithm is a kind of total blindness's algorithm, does not utilize the pilot bit of WCDMA agreement defined, is a kind of waste of resource; Also have some other beamforming algorithm, like sign indicating number filtering and cascade training method, in calculating process, all relate to the computing that large-scale matrix multiplies each other and inverts, complexity and operand are excessive, are not easy to hardware and realize.At present, the technical scheme that does not also at all address the above problem.
Summary of the invention
The present invention is just in order to overcome the problem that exists in the above-mentioned prior art, and proposes a kind of adaptive beam formation method that is applicable in the broadband CDMA system, to reach the minimizing operand, reduces the computing complexity, improves processing accuracy and speed simultaneously.
In order to reach said goal of the invention, the present invention provides a kind of wave beam formation method that is applicable in the broadband CDMA system, and it comprises the following steps:
The array signal carries out the spatial domain to be handled, and said array signal is the baseband signal X of time delay alignment, comprising: to each frame,
During the pilot bit of first time slot; With the heavily expansion scrambled symbols of known up channel frequency pilot sign signal r as a reference; Carry out computing cross-correlation with said baseband signal X; Obtain cross-correlation matrix
and calculate the suboptimum weights, up to all pilot bit end of first time slot;
During the pilot bit of information symbol position and other time slot; With said suboptimum weights is initial value; The heavily expansion scrambled signals that heavily expands scrambled signals and known pilot bits with the information symbol position of despreading descrambling is a reference signal respectively; Carry out iteration according to minimum mean square error criterion; Obtain self adaptation suboptimum weights
and carry out wave beam formation, obtain Y=W * X with said self adaptation suboptimum weights W;
Wherein, Carry out iteration according to minimum mean square error criterion; Obtain self adaptation suboptimum weights
and carry out wave beam formation, obtain Y=W * X and comprise with said self adaptation suboptimum weights W:
Weights when finishing the pilot bit of first time slot are input to multiplier; Multiply each other with said baseband signal X, the wave beam that obtains each array element forms signal, forms signal to the wave beam of each array element through synthetic one road signal of adder; Be input to the calculating iteration error module that heavily expands iteration module and the descrambling module of time domain processing module to this signal respectively again; Wherein, be input to the signal of the calculating iteration error module that heavily expands iteration module, the quilt during as the error of calculation subtracts vector; Be divided into I circuit-switched data and Q circuit-switched data after being input to the signal descrambling of descrambling module of time domain processing module, said Q circuit-switched data gets into the despreading module; Data are handled after utilizing channel estimating and compensating module to despreading, adjudicate again, and the sign bit that obtains is input to and heavily expands iteration module;
During current time is the information symbol position; The sign bit that obtains after the said judgement is input to the calculating iteration error module that heavily expands iteration module after overweight expansion, scrambling; Adder signal subtraction with previous input; Obtain error signal, be input to the spatial domain wave beam and form in the new weights module of calculating of module;
During when current time being the pilot bit of other time slot; Heavily expand scrambled signals as an input of heavily expanding the calculating iteration error module of iteration module by known up channel pilot bit; Adder signal subtraction with previous input; Obtain error signal, be input to the spatial domain wave beam and form in the new weights module of calculating of module;
Judge that weights with the new weights module output of said calculating carry out iteration error that wave beam formation obtains whether within convergence threshold; As not, then return the array signal and carry out the spatial domain treatment step; In this way, then preserve said weights, be used for carrying out wave beam and form as said self adaptation suboptimum weights W.
The good effect that the present invention can bring is; Adopt method provided by the invention to realize that adaptive beam forms; System is constituted simplify, technical difficulty and operand reduce greatly, and the R&D cycle shortens; And the performance of intelligent antenna of broadband CDMA system base station processes is improved greatly, make things convenient for Project Realization.
The present invention will combine embodiment to be elaborated with reference to accompanying drawing, so that to the object of the invention, technical characterictic and good effect have more deep understanding.
Description of drawings
Fig. 1 overall flow figure of the present invention;
Multiple target array algorithm structure chart is heavily expanded in the auxiliary despreading of Fig. 2 pilot bit based on minimum mean square error criterion of the present invention.
Embodiment
As shown in Figure 1, flow process begins, step 101; At first; During the pilot bit of first time slot; With the heavily expansion scrambled symbols of known up channel frequency pilot sign signal as a reference; Carry out computing cross-correlation with the array received vector X of the current information position of time delay alignment; Obtain the suboptimum weights; During the pilot bit of first time slot of every frame; With the signal r as a reference of the signal after the pilot signal spectrum-spreading and scrambling; The approximate solution of asking the pilot signal X of array received and the cross-correlation matrix of reference signal r
to obtain according to minimum mean square error criterion is carried out wave beam formation Y=W * X as self adaptation suboptimum weights
and with the weights
that top two steps calculate; Y is time domain processing module 22 and the input of heavily expanding iteration module 23, step 102; The signal that wave beam is formed carries out descrambling, despreading; During the pilot bit of information symbol position and other time slot; With the suboptimum weights is initial value, and the heavily expansion scrambled signals that heavily expands scrambled signals and known pilot bits with the information symbol position of descrambling and de-spreading is a reference signal respectively, carries out LMS (least mean square algorithm) iteration; Obtain weights, step 103; Judge least mean-square error whether within convergence threshold, step 104; If do not satisfy, then repeated execution of steps 102, step 103; If error meets the demands, then preserve these weights, be used for wave beam to form the signal data of this time slot, step 105; After forming with convergence weights wave beam, the I circuit-switched data of descrambling and de-spreading up channel is accomplished the reception of information, statistics and output signal-to-noise ratio, step 106; Last flow process finishes step 107.
As shown in Figure 2; For the schematic diagram that multiple target array adaptive algorithm realizes is heavily expanded in the auxiliary despreading of the pilot bit based on minimum mean square error criterion provided by the present invention; The wave beam that this figure is depicted as to the unique user individual paths forms, and can the unique user individual paths that it comprised be superposeed for multipath and multi-user.This figure specifies as follows: the signal of array received becomes baseband signal through radio-frequency front-end and baseband-converted, carries out self-adaptive processing in base band.Baseband signal supposes that at first the array received signal is the baseband signal 214 of time delay alignment because the influence of space channel can produce changes of properties such as time delay expansion and angle spread, and next, we will carry out algorithm process to 214.During the pilot bit of first time slot, the signal 234 that heavily expands scrambling by known pilot bits signal and baseband signal 214 is as a reference asked cross-correlation matrix together, calculates the suboptimum weights, finishes up to all pilot bit of first time slot; Weights when finishing the pilot bit of first time slot are input to multiplier 211, form signal to the wave beam of each array element through adder 212 synthetic one road signals, become two paths of signals to this signal decomposition again; One the tunnel is input to the calculating iteration error module 233 that heavily expands iteration module 23, and the quilt during as the error of calculation subtracts vector, and another road is input to the descrambling module 221 of time domain processing module 22; The Q circuit-switched data of the data behind the descrambling gets into despreading module 222, and the data unit that despreading is come out is a bit, and exploitable channel is estimated and compensating module 223; 224 pairs of despread data are handled; Reduce the influence of channel, the data after the judgement 225 are 1 ,-1; ... sign bit, be input to and heavily expand iteration module 23; During current time is information bit; Be input to behind overweight expansion module 231, scrambling module 232 by the sign bit of time domain processing module 22 input and calculate iteration error module 233; Adder 212 signal subtractions with previous input; Obtain error signal, be input to the spatial domain wave beam and form in the new weights module 213 of calculating of module 21; During when current time being the pilot bit of other time slot; Input of heavily expanding scrambled signals 235 conduct calculating iteration error modules 233 by known pilot bits; Adder 212 signal subtractions with previous input; Obtain error signal, be input to the spatial domain wave beam and form in the new weights module 213 of calculating of module 21.Be input to the signal of the new weights module 213 of calculating and the signal 214 of time delay alignment; Based on minimum mean square error criterion; Iteration is obtained weights, meets the demands if carry out the iteration error that wave beam forms with these weights; The data de-scrambling that then this wave beam is formed, despreading, channel estimating compensation and RAKE merge, and export.
Claims (2)
1. one kind is applicable to the wave beam formation method in the broadband CDMA system, and said wave beam formation method may further comprise the steps:
The array signal carries out the spatial domain to be handled, and said array signal is the baseband signal X of time delay alignment, comprising: to each frame,
During the pilot bit of first time slot; With the heavily expansion scrambled symbols of known up channel frequency pilot sign signal r as a reference; Carry out computing cross-correlation with said baseband signal X; Obtain cross-correlation matrix
and calculate the suboptimum weights, up to all pilot bit end of first time slot;
During the pilot bit of information symbol position and other time slot; With said suboptimum weights is initial value; The heavily expansion scrambled signals that heavily expands scrambled signals and known pilot bits with the information symbol position of despreading descrambling is a reference signal respectively; Carry out iteration according to minimum mean square error criterion; Obtain self adaptation suboptimum weights
and carry out wave beam formation, obtain Y=W * X with said self adaptation suboptimum weights W;
Wherein, Carry out iteration according to minimum mean square error criterion; Obtain self adaptation suboptimum weights
and carry out wave beam formation, obtain Y=W * X and comprise with said self adaptation suboptimum weights W:
Weights when finishing the pilot bit of first time slot are input to multiplier; Multiply each other with said baseband signal X, the wave beam that obtains each array element forms signal, forms signal to the wave beam of each array element through synthetic one road signal of adder; Be input to the calculating iteration error module that heavily expands iteration module and the descrambling module of time domain processing module to this signal respectively again; Wherein, be input to the signal of the calculating iteration error module that heavily expands iteration module, the quilt during as the error of calculation subtracts vector; Be divided into I circuit-switched data and Q circuit-switched data after being input to the signal descrambling of descrambling module of time domain processing module, said Q circuit-switched data gets into the despreading module; Data are handled after utilizing channel estimating and compensating module to despreading, adjudicate again, and the sign bit that obtains is input to and heavily expands iteration module;
During current time is the information symbol position; The sign bit that obtains after the said judgement is input to the calculating iteration error module that heavily expands iteration module after overweight expansion, scrambling; Adder signal subtraction with previous input; Obtain error signal, be input to the spatial domain wave beam and form in the new weights module of calculating of module;
During when current time being the pilot bit of other time slot; Heavily expand scrambled signals as an input of heavily expanding the calculating iteration error module of iteration module by known up channel pilot bit; Adder signal subtraction with previous input; Obtain error signal, be input to the spatial domain wave beam and form in the new weights module of calculating of module;
Judge that weights with the new weights module output of said calculating carry out iteration error that wave beam formation obtains whether within convergence threshold; As not, then return the array signal and carry out the spatial domain treatment step; In this way, then preserve said weights, be used for carrying out wave beam and form as said self adaptation suboptimum weights W.
2. a kind of wave beam formation method that is applicable in the broadband CDMA system as claimed in claim 1; It is characterized in that it is to be directed against the unique user individual paths that said array signal carries out the spatial domain processing, and multipath and multi-user are the result's of said unique user individual paths stacks.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN031154158A CN1549473B (en) | 2003-05-07 | 2003-05-07 | Beam forming method adapted to wide band CDMA system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN031154158A CN1549473B (en) | 2003-05-07 | 2003-05-07 | Beam forming method adapted to wide band CDMA system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1549473A CN1549473A (en) | 2004-11-24 |
| CN1549473B true CN1549473B (en) | 2012-12-05 |
Family
ID=34320250
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN031154158A Expired - Fee Related CN1549473B (en) | 2003-05-07 | 2003-05-07 | Beam forming method adapted to wide band CDMA system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN1549473B (en) |
Families Citing this family (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1875633A4 (en) | 2005-04-25 | 2012-03-21 | Korea Electronics Telecomm | Apparatus and method of on-channel repeater |
| CN100544231C (en) | 2005-06-08 | 2009-09-23 | 中兴通讯股份有限公司 | Smart antenna implementation method and smart antenna based on software radio are realized system |
| CN101651483B (en) * | 2009-09-23 | 2013-08-07 | 中国人民解放军信息工程大学 | Method and device for synthesizing and enhancing signals based on randomly laid antenna arrays |
| CN101645728B (en) * | 2009-09-23 | 2013-01-02 | 中国人民解放军信息工程大学 | Multi-antenna signal synthesis strengthening method based on parametric self-adaptive compensation and device |
| CA2787774C (en) * | 2010-01-22 | 2019-02-12 | Sharp Kabushiki Kaisha | Transmission device, reception device, communication system, and communication method |
| CN103178894B (en) * | 2013-02-04 | 2015-08-26 | 中国人民解放军信息工程大学 | A kind of signal synthesis method of multi signal stream and device |
| CN106688194B (en) * | 2014-12-31 | 2020-04-21 | 华为技术有限公司 | Array antenna beam adjusting device and method |
| EP3253104B1 (en) | 2015-01-29 | 2021-08-25 | Sony Group Corporation | Device and method |
| CN111418163B (en) * | 2017-12-07 | 2023-04-11 | 三菱电机株式会社 | Wireless device and wireless communication control method |
| CN111694023A (en) * | 2020-06-08 | 2020-09-22 | 西安交通大学 | Satellite navigation anti-interference receiving processing method based on despreading and despreading |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1339888A (en) * | 2001-10-23 | 2002-03-13 | 杨大成 | Receiver structure applying intelligent antenna and combined detection in radio communication system and its algorithm |
| CN1373577A (en) * | 2001-03-07 | 2002-10-09 | 华为技术有限公司 | Time-space united multi-path search method and device for wireless CDMA communication system |
-
2003
- 2003-05-07 CN CN031154158A patent/CN1549473B/en not_active Expired - Fee Related
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1373577A (en) * | 2001-03-07 | 2002-10-09 | 华为技术有限公司 | Time-space united multi-path search method and device for wireless CDMA communication system |
| CN1339888A (en) * | 2001-10-23 | 2002-03-13 | 杨大成 | Receiver structure applying intelligent antenna and combined detection in radio communication system and its algorithm |
Non-Patent Citations (6)
| Title |
|---|
| 丁杰伟，李鲲鹏，黄超，傅丰林.WCDMA***中智能天线PSALS-SDRMTA自适应算法.通信学报24 2.2003,24(2),78-83. |
| 丁杰伟,李鲲鹏,黄超,傅丰林.WCDMA***中智能天线PSALS-SDRMTA自适应算法.通信学报24 2.2003,24(2),78-83. * |
| 张华，李会勇，龚耀寰.WCDMA***基站阵列接收方案带训练序列的LMS-DRMTA算法.电子与信息学报24 4.2002,24(4),527-533. |
| 张华,李会勇,龚耀寰.WCDMA***基站阵列接收方案带训练序列的LMS-DRMTA算法.电子与信息学报24 4.2002,24(4),527-533. * |
| 张华，龚耀寰.DS/CDMA***上行链路的2D-Rake及PPIC接收方案.电波科学学报17 4.2002,17(4),412-417. |
| 张华,龚耀寰.DS/CDMA***上行链路的2D-Rake及PPIC接收方案.电波科学学报17 4.2002,17(4),412-417. * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN1549473A (en) | 2004-11-24 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| KR100735813B1 (en) | Method of generating weighted vector in the development of smart antennas for IMT-2000 CDMA wireless communication | |
| US5724378A (en) | CDMA multiuser receiver and method | |
| US7079570B2 (en) | Communication system with receivers employing generalized two-stage data estimation | |
| CN1549473B (en) | Beam forming method adapted to wide band CDMA system | |
| Sengupta et al. | On multipath channel estimation for CDMA systems using multiple sensors | |
| JP4183134B2 (en) | Smart antenna and beam forming method and apparatus thereof | |
| Min et al. | Direction-of-arrival tracking scheme for DS/CDMA systems: Direction lock loop | |
| CN100433594C (en) | Adaptive beamforming method in wideband code division multiple access system | |
| KR100329110B1 (en) | Space-Time Array Receive System Using Chip-Level, Time-Reference Beamforming Algorithm | |
| JPH0964846A (en) | Cdma multi-user receiver and its method | |
| Sengupta et al. | Maximum likelihood multipath channel parameter estimation in CDMA systems | |
| Yang et al. | A novel adaptive antenna array for DS/CDMA code acquisition | |
| Russell et al. | Application of APES to adaptive arrays on the CDMA reverse channel | |
| Chang et al. | Chip-level 2-D RAKE receiver with symbol-level searcher beamforming | |
| Sengupta et al. | Fixed point error analysis of multiuser detection and synchronization algorithms for CDMA communication systems | |
| CN100373832C (en) | Code filtering self-adaptive wave beam formation method | |
| Shao-li et al. | Performance of active codes detection algorithms for the downlink of TD-SCDMA system | |
| Liu et al. | Adaptive minimum bit error rate multitarget array algorithm | |
| Chen et al. | A RAKE receiver design for WCDMA FDD uplink with an RLS-based adaptive beamforming scheme | |
| KR100406529B1 (en) | Smart antenna base station system and the method of chip level beamforming based and his action method to use standard signal production apparatus and the method and he | |
| Du et al. | An adaptive multiuser detection algorithm for CDMA systems using antenna diversity | |
| Liu et al. | Implementation of adaptive beamforming based on QR decomposition for CDMA | |
| Affes et al. | Near-far resistant single-user channel identification by interference subspace rejection in wideband CDMA | |
| Chang et al. | Chip-level beamforming vs. symbol-level beamforming in coherent CDMA adaptive antenna array systems | |
| Im et al. | An iterative decorrelator with multipath combiners for CDMA frequency-selective fading channels |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20121205 Termination date: 20210507 |
|
| CF01 | Termination of patent right due to non-payment of annual fee |