CN100337415C - Multipath searching method and apparatus for CDMA communication system - Google Patents
Multipath searching method and apparatus for CDMA communication system Download PDFInfo
- Publication number
- CN100337415C CN100337415C CNB021374635A CN02137463A CN100337415C CN 100337415 C CN100337415 C CN 100337415C CN B021374635 A CNB021374635 A CN B021374635A CN 02137463 A CN02137463 A CN 02137463A CN 100337415 C CN100337415 C CN 100337415C
- Authority
- CN
- China
- Prior art keywords
- power spectrum
- time
- delay power
- unit
- energy value
- 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
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02D—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN INFORMATION AND COMMUNICATION TECHNOLOGIES [ICT], I.E. INFORMATION AND COMMUNICATION TECHNOLOGIES AIMING AT THE REDUCTION OF THEIR OWN ENERGY USE
- Y02D30/00—Reducing energy consumption in communication networks
- Y02D30/70—Reducing energy consumption in communication networks in wireless communication networks
Landscapes
- Mobile Radio Communication Systems (AREA)
Abstract
The present invention provides a method for multiple-path search and a device, which can complete multiple-path search processing rapidly and stably. According to the method for multiple-path search, a plurality of time delay power spectrums in a section of time interval are processed through a minimum value filter to generate a new time delay power spectrum firstly, wherein the energy value of each phase in the new time delay power spectrum is equal to the minimum value of energy values on a plurality of corresponding phases in the time delay power spectrums. Then a multiple-path judgment threshold is determined according to the new time delay power spectrum. The multiple-path judgment threshold is used for multiple-path judgment. Compared with the prior art, the method can effectively filter noise information in time delay power spectrums, and thus, false alarm probability and alarm dismissal probability are reduced. Moreover, because the processing does not greatly increase the complexity and the system overhead of the device for multiple-path search, the realization mode of the device is simple and economic.
Description
Technical field
The present invention relates to method for receiving and processing signal and device in code division multiple access (CDMA) communication system, particularly multipath searching method and the device in the cdma receiver system.
Background technology
Compare with wire message way, wireless channel environment is comparatively abominable, have many interference such as decline, multipath, so the whether suitable of the method for receiving and processing signal of wireless communication system is the decisive factor that influences systematic function always.
So-called multipath transport phenomena, refer to from the signal of transmitter emission and arrive receiver through the different transmission path of too much bar, therefore receiver will receive the transmission signals of the mulitpath that decline degree and phase place do not wait with different time-delays, and these multipath signals can cause the multipath fading phenomenon when mixing arrival receivers.Fig. 1 and Fig. 2 show under ideal situation and the actual conditions time-delay power spectrum from a certain transmitter received signal respectively, transverse axis among the figure is represented the time that signal receives, vertical pivot is represented the energy or the power of received signal, time and power that each arrow 101～106 expression multipath signals occur on receiver.In real system, because the combined influence of factors such as the non-synchronous fully and noise of the imperfection of code length, sign indicating number, system, multipath signal is not as shown in Figure 1 discrete type vertical line on the power spectrum in time-delay, but the time dependent full curve of energy as shown in Figure 2.Still be formed with signal peak among Fig. 2 with near Fig. 1 corresponding peak value position, but the position is not accurate correspondence, and, then almost can't distinguishes for 104 and 106 two less peaks of energy.In addition, on 20 positions that indicate a false multipath signal that is caused by the higher noise energy appears also.
Although there are various noise jamming in the multipath signal of actual reception, still comprised utilizable information, therefore for example in cdma system, receiver can be by merging the signal to noise ratio that multipath signal improve received signal.The general RAKE reception technique that adopts in cdma receiver carries out diversity and merges to obtain better receptivity the multipath signal interval greater than a chip.RAKE receiver generally is made up of Multipath searching unit, despreading descrambling unit/unit group, channel estimating and compensating unit and multipath merge cells.The Multipath searching unit is used for determining to belong to from the baseband signal of input the relative time position or the phase place of each multipath signal of same transmitter or user, on the multi-path location that despreading descrambling unit/unit group is then determined in the Multipath searching unit signal is carried out the despreading scramble process to obtain each multipath signal.Because the decline degree and the phase place of each road multipath signal do not wait, therefore need they to be carried out signal compensation and correction by channel estimating and compensating unit.At last, the multipath merge cells merges each multipath signal through overcompensation to obtain to have the signal than high s/n ratio.
Above-mentioned Multipath searching unit in fact also is used to system synchronization.Generally speaking, system adopts the two-stage method of synchronization, promptly at first carry out Multipath searching, each bar multipath signal in obtaining on a large scale, carry out multipath tracking then and handle, Multipath searching is handled the rough position that obtains adjust to determine accurate multi-path location and to overcome possible the moving of multipath peak position in the cycle of a Multipath searching.Therefore, Multipath searching is actually a kind of thick simultaneous techniques that obtains the multipath home position in big time range.
The general structure of Multipath searching unit as shown in Figure 3.In the Multipath searching unit, at first according to certain condition code baseband signal is carried out the despreading scramble process, thereby obtain the time-delay power spectrum of the despreading descrambling output energy of relative users on different time position (or phase place) by despreading descrambling unit/unit group 31.Phase place smooth unit 32 is carried out smoothing processing to suppress the time-delay power spectrum behind the noise to the multipath signal on each phase place.Peak filter 33 detects peak and the corresponding energy through the time-delay power spectrum after the inhibition noise processed, and exports testing result to multi-path judging unit/unit group 34.34 of multi-path judging unit/unit group determine according to predefined decision rule whether detected peak position is the multi-path location of signal, if be defined as multi-path location, then export the phase information of this multi-path location, but also transmit control signal to despreading descrambling unit/unit group 31.In above-mentioned Multipath searching unit, despreading descrambling unit/unit group 31 is with the fast speeds processing signals, can be described as the front-end processing part, phase place smooth unit 32, peak filter 33 and multi-path judging unit/unit group 34 can be described as the back-end processing part with symbol level (perhaps slower speed step) velocity process signal.
The major function of phase place smooth unit 32 is to suppress influence that ubiquitous noise causes multi-path judging and sudden big noise is had restriction, the general linear filter that adopts is realized for example finite impulse response (FIR) filter or infinite impulse response (IIR) filter.The most frequently used is the first order IIR filtering device, and its structure as shown in Figure 4.In this filter, finish the product calculation of intake and filter coefficient α by multiplier 71, carry out delay process and delay process result and coefficient (1-α) multiplied each other by 73 pairs of delay registers output energy by multiplier 72, by adder 74 with the output results added of multiplier 71 and 72 as exporting energy.The value of filter coefficient α has determined the performance of this filter, if factor alpha is bigger, then whole system is more stable, and false alarm probability (be about to non-multipath signal erroneous judgement and be the probability of multipath signal) is lower, but the multipath searching time is also longer; If side reaction coefficient is less, then system response is relatively sensitiveer, and the multipath searching time is also short, but erroneous judgement appears in false alarm probability also corresponding increase easily.
Multi-path judging unit/unit group 34 can adopt various decision rules to determine whether the peak position of peak filter output is multi-path location.The simplest a kind of decision rule is, if peak energy, determines then that this peak position is a multi-path location greater than predetermined threshold value T.Obviously, the size of threshold value T has determined the reliability of judgement.If T is bigger, then false alarm probability is less, but false dismissal probability (be about to the multipath signal erroneous judgement and be the probability of non-multipath signal) is bigger; Otherwise if T is bigger, then false dismissal probability is less, but false alarm probability is bigger.
In above-mentioned Multipath searching unit, each unit before the multi-path judging unit is linear unit, and its signal detecting method all is linear.Verified in theory, linear signal detects and can not make false alarm probability and false dismissal probability minimum simultaneously.Therefore when the design system parameter, just have between false alarm probability and false dismissal probability, get compromise, cause systematic function not very good.In addition, the response speed of linear system also is a ubiquitous contradiction with final precision, that is, can not rely on linear signal to detect to obtain not only stable but also multi-path location decision method fast.
Summary of the invention
The purpose of this invention is to provide a kind of multipath searching method and the device that can finish the Multipath searching processing fast and stable.
According to the multipath searching method that is used for code division multiple address communication system of the present invention, receiver in the described communication system obtains time-delay power spectrum from the received signal of same transmitter by the despreading scramble process, and described receiver obtains multi-path location according to following steps from the time-delay power spectrum:
(1) generate a new time-delay power spectrum according to some time-delay power spectrum of a period of time at interval, the energy value in the wherein said new time-delay power spectrum on each phase place equals the minimum energy value on a plurality of respective phase in described some time-delay power spectrum;
(2) determine the multi-path judging threshold value according to the average energy value of described new time-delay power spectrum, the difference of wherein said multi-path judging threshold value and described the average energy value is a predefined constant; And
(3) with the energy value of each peak position in the described new time-delay power spectrum and described multi-path judging threshold ratio, if this energy value is more than or equal to described multi-path judging threshold value, judge that then this peak position is multi-path location and phase place and the energy value of exporting this peak position, otherwise, judge that this peak position is non-multi-path location.
Form by front-end processing unit and back-end processing unit according to the multipath searching device that is used for code division multiple address communication system of the present invention, described front-end processing unit is converted to time-delay power spectrum from same transmitter received signal by the despreading scramble process with baseband receiving signals, multi-path location is determined in described back-end processing unit from the time-delay power spectrum, described back-end processing unit comprises:
The minimum value filter unit, be used for generating a new time-delay power spectrum according to some time-delay power spectrum of a period of time at interval, the energy value in the wherein said new time-delay power spectrum on each phase place equals the minimum energy value on a plurality of respective phase in described some time-delay power spectrum;
Multi-path judging threshold value generation unit is used to calculate the average energy value of the new time-delay power spectrum that described minimum value filter unit obtains, and it is determined the multi-path judging threshold value mutually with a predefined constant;
The peak filtering unit, the phase place and the energy value of new each peak position of time-delay power spectrum that is used for determining that described minimum value filter unit obtains; And
The multi-path judging unit, the energy value of each peak position and described multi-path judging threshold ratio are in the new time-delay power spectrum that described peak filtering unit is definite, if this energy value is more than or equal to described multi-path judging threshold value, judge that then this peak position is multi-path location and phase place and the energy value of exporting this peak position, otherwise, judge that this peak position is non-multi-path location.
In method and apparatus of the present invention, a plurality of time-delay power spectrum generate a new time-delay power spectrum through the minimum value Filtering Processing, compare with phase place smoothing processing mode of the prior art, therefore this Nonlinear Processing mode can reduce false alarm probability and alarm dismissal probability effectively with the noise information filtering in the time-delay power spectrum.And above-mentioned processing do not increase considerably the complexity and the overhead of multipath searching device, so implementation is easy and economical.
Description of drawings
Fig. 1 is the time-delay power spectrum of ideally wireless receiving signal.
Fig. 2 is the time-delay power spectrum of wireless receiving signal under the actual conditions.
Fig. 3 is the schematic diagram of Multipath searching unit under the prior art.
Fig. 4 is the schematic diagram of single order IIR filter.
Fig. 5 is the flow chart according to the multipath searching method of preferred embodiment of the present invention.
Fig. 6 is the schematic diagram according to the multipath searching device of preferred embodiment of the present invention.
Fig. 7 is the schematic diagram according to minimum value filter in the multipath searching device of preferred embodiment of the present invention.
Fig. 8 is the schematic diagram according to peak filter in the multipath searching device of preferred embodiment of the present invention.
Embodiment
In the time-delay power spectrum of real system, except that the true multi-path location of respective user signal, signal on other time-delay position or the phase place all is regarded as white Gaussian noise, erroneous judgement is made of false-alarm and omission, wherein, false-alarm mainly since on the non-multi-path location the paroxysmal increase of noise energy cause, and omission mainly is to be caused by the additive white Gaussian noise two aspect factor actings in conjunction that occur big negative value on not high and this multi-path location of multipath energy itself.In other words, the sudden increase of white Gaussian noise is the main cause that causes false-alarm or omission erroneous judgement.It is to be noted in addition, owing to the variation that wireless channel between transmitter and the receiver is interior at certain time intervals is little, therefore the time-delay power spectrum in this interval may present periodic structure roughly, promptly, this time-delay power spectrum can be divided into several time-delay power spectrum, and they have similar multi-path location and distribute.Based on above-mentioned analysis, core concept of the present invention is, can above-mentionedly somely have in the time-delay power spectrum that similar multi-path location distributes the energy value on the same phase place and determine whether this phase place belongs to multi-path location by investigating, particularly, if subscriber signal, then on corresponding a plurality of phase places, energy value all should be bigger, on the contrary, if noise signal, then on corresponding a plurality of phase places, all keep the probability of higher-energy value (no matter being negative value or positive) obviously to reduce, can improve the accuracy of multi-path location judgement thus.
According to method of the present invention, some time-delay power spectrum that at first selected a period of time is interior are at interval also handled in the following manner, that is,, choose the energy value of minimum energy value as corresponding phase in the new time-delay power spectrum for one group of energy value on these each phase places of time-delay power spectrum; Next is to determine the multi-path judging threshold value according to new time-delay power spectrum, thereby specifically comprises the average energy value of the time-delay power spectrum that calculating is new and itself and a predefined constant addition are obtained the multi-path judging threshold value; Can carry out multi-path judging according to the multi-path judging threshold value that obtains at last, in fact be exactly with the energy value of each peak position in the new time-delay power spectrum and multi-path judging threshold ratio, if this energy value is more than or equal to the multi-path judging threshold value, judge that then this peak position is multi-path location and phase place and the energy value of exporting this peak position, otherwise, judge that this peak position is non-multi-path location.
Below by Fig. 5 a preferred embodiment according to the inventive method is described.As shown in Figure 5, at first enter step S1, thereby baseband signal is comprised that the front-end processing of despreading scramble process obtains the time-delay power spectrum from a certain transmitter received signal; Then enter step S2, the corresponding delay power spectrum of storing when in memory, upgrading multi-path judging last time with new time-delay power spectrum; Enter step S3 subsequently, the stored number of this time-delay power spectrum is counted; Then, judge whether the time-delay power spectrum quantity of current storage satisfies the quantity L of judgement needs, and L is predetermined system parameters, can determine according to system's concrete condition or emulation at step S4.If satisfy, then make counter O reset and change step S5 over to, otherwise return step S1; In step S5, L time-delay power spectrum carried out the minimum value Filtering Processing to obtain a new time-delay power spectrum, particularly, in this L time-delay power spectrum, for each corresponding phase place L energy value arranged all, in order to improve the judgement accuracy, the minimum value in this L energy value is chosen to be the energy value of respective phase in the new time-delay power spectrum.
Enter step S6 subsequently, the average energy value T of the filtered time-delay power spectrum of calculated minimum
0Then in step S7, calculate decision threshold T with following formula:
T＝T
0+T
1
T wherein
1Be predetermined threshold constant, can determine according to system's concrete condition or emulation.
In step S8, whether all periods of judging the time-delay power spectrum after the minimum value Filtering Processing all pass through peak filtering is handled, if "Yes" then finishes this multi-path judging process, otherwise change step S9 over to, continue that time-delay next period of power spectrum is carried out peak filtering and handle; Then in step S10, judge whether there is peak position in this period,, then change step S11 over to if there is peak position according to the peak filtering result, otherwise, step S8 then returned; At step S11, the energy value and the decision threshold T of peak position compared, be multi-path location and change step S12 over to if the peak position energy value, is then judged this peak position more than or equal to decision threshold T, otherwise, judge that this peak position is non-multi-path location and returns step S8; At step S12, step S8 is exported and returned to the energy value and the phase place that are judged as the peak position of multi-path location.
Below by Fig. 6 a preferred embodiment according to multipath searching device of the present invention is described.As shown in Figure 6, this multipath searching device comprises front-end processing unit 41 and back-end processing unit 42, wherein, front-end processing unit is converted to time-delay power spectrum from same transmitter received signal by the despreading scramble process with baseband receiving signals, and the rear end processing unit is then determined multi-path location from this time-delay power spectrum.
Front-end processing unit 41 comprises front-end processing module 411 and square summation module 412 compositions, and front-end processing module 411 can be sliding correlation detector/correlator bank or matched filter.It will be apparent to one skilled in the art that the operation principle of sliding correlation detector/correlator bank and matched filter and structure all are known, therefore repeat no more.Baseband signal is isolated the signal of each user on different delayed time position or phase place after handling through front-end processing module 411, and this signal comprises I road component and Q road component.Thereby this signal is made the time-delay power spectrum that square summation operation obtains each user in square summation module 412 then.When carrying out multi-path judging, front-end processing unit 41 can serial mode offer back-end processing unit 42 one by one with L the time-delay power spectrum that obtains in a period of time interval at every turn.The quantity L of time-delay power spectrum can determine according to system's concrete condition or emulation.
Back-end processing unit 42 comprises minimum value filter 421, peak filter 422, multi-path judging threshold value generation unit 423 and multi-path judging unit 424.
The operation principle of above-mentioned minimum value filter 421 is below described.When front end processing unit 41 is exported the time-delay power spectrum one by one with serial mode, control unit 124 is write by control and is enabled the full duplex dual port RAM 1222-122 (L-1) that enabling on selector 1211～121 (L-1) output selects signal to choose to write the current delay power spectrum, when for example power spectrum is delayed time in the 1st of front-end processing unit 41 output, if it is stored in the full duplex dual port RAM 1221, then control unit 124 makes to write and enables selector 1211 output WEs and be output as 1, other is write the WE that enables selector and is output as 0, meanwhile, control unit 124 writes the address by the read/write address port input of full duplex dual port RAM 1221, thereby the data of the 1st time-delay power spectrum are write, and the used time-delay power spectrum data of last time multi-path judging of original storage promptly is updated in this full duplex dual port RAM.Except last time-delay power spectrum, other time-delay power spectrum write that the rest may be inferred, repeat no more.For last time-delay power spectrum, it is directly sent into chooses minimum value unit 123.The address is read in the read/write address port input of control unit 124 by full duplex dual port RAM 1221-122 (L-1), thus with the data read of (L-1) individual time-delay power spectrum of memory ram storage to choosing minimum value unit 123.Choose the time-delay power spectrum data that 123 bases in minimum value unit directly read from the time-delay power spectrum data of front-end processing unit input with in the RAM and carry out the minimum value selection operation, thereby finish minimum value filtering to generate new time-delay power spectrum.
As shown in Figure 6, multi-path judging threshold value generation unit 423 is made up of accumulator 113, divider 114 and adder 115, the energy value of each phase place of time-delay power spectrum of 113 pairs of minimum value filters of accumulator, 421 outputs adds up, and divider obtains the accumulation result of accumulator 113 the average energy value T of this time-delay power spectrum divided by the phase place sum
0, and adder 115 is with the average energy value T
0With a pre-set threshold constant T
1Obtained multi-path judging threshold value T mutually.
Each peak that the multi-path judging threshold value T that multi-path judging unit 424 is exported according to multipath threshold value decision unit 423 exports peak filter 424 carries out multipath and judges, particularly, energy value and multi-path judging threshold value T comparison with each peak position of peak filtering unit output, if this energy value is more than or equal to the multi-path judging threshold value, judge that then this peak position is multi-path location and phase place and the energy value of exporting this peak position, otherwise, judge that this peak position is non-multi-path location.Multi-path judging unit 424 also exports control command to front-end processing module 411 in addition.
Claims (7)
1. multipath searching method that is used for code division multiple address communication system, receiver in the described communication system obtains received signal time-delay power spectrum from same transmitter by the despreading scramble process, it is characterized in that described receiver obtains multi-path location according to following steps from the time-delay power spectrum:
(1) generate a new time-delay power spectrum according to some time-delay power spectrum of a period of time at interval, the energy value in the wherein said new time-delay power spectrum on each phase place equals the minimum energy value on a plurality of respective phase in described some time-delay power spectrum;
(2) the average energy value with described new time-delay power spectrum is obtained the multi-path judging threshold value mutually with a predefined constant; And
(3) with the energy value of each peak position in the described new time-delay power spectrum and described multi-path judging threshold ratio, if this energy value is more than or equal to described multi-path judging threshold value, judge that then this peak position is multi-path location and phase place and the energy value of exporting this peak position, otherwise, judge that this peak position is non-multi-path location.
2. multipath searching method as claimed in claim 1 is characterized in that, the quantity and the described predefined constant that generate the used some time-delay power spectrum of new time-delay power spectrum are determined by emulation experiment.
3. multipath searching device that is used for code division multiple address communication system, form by front-end processing unit and back-end processing unit, described front-end processing unit is converted to time-delay power spectrum from same transmitter received signal by the despreading scramble process with baseband receiving signals, multi-path location is determined in described back-end processing unit from the time-delay power spectrum, it is characterized in that described back-end processing unit comprises:
The minimum value filter unit, be used for generating a new time-delay power spectrum according to some time-delay power spectrum of a period of time at interval, the energy value in the wherein said new time-delay power spectrum on each phase place equals the minimum energy value on a plurality of respective phase in described some time-delay power spectrum;
Multi-path judging threshold value generation unit is used to calculate the average energy value of the new time-delay power spectrum that described minimum value filter unit obtains, and it is determined the multi-path judging threshold value mutually with a predefined constant;
The peak filtering unit, the phase place and the energy value of new each peak position of time-delay power spectrum that is used for determining that described minimum value filter unit obtains; And
The multi-path judging unit, the energy value of each peak position and described multi-path judging threshold ratio are in the new time-delay power spectrum that described peak filtering unit is definite, if this energy value is more than or equal to described multi-path judging threshold value, judge that then this peak position is multi-path location and phase place and the energy value of exporting this peak position, otherwise, judge that this peak position is non-multi-path location.
4. device as claimed in claim 3, it is characterized in that, with L time-delay of serial mode output power spectrum, wherein L is the quantity of described some time-delay power spectrum to described front-end processing unit by its output, and the minimum value filter unit in the described back-end processing unit comprises:
Control unit;
(L-1) individual writing enables selector, and each is write and enables selector and all have under the control of described control unit output enable and select writing of signal to enable selector output end;
Enable selector (L-1) individual full duplex dual port RAM one to one with described (L-1) individual writing, each full duplex dual port RAM comprises:
The full duplex dual port RAM input that links to each other with described front-end processing unit output;
The full duplex dual port RAM output of the time-delay power spectrum of its storage of output under described control unit control;
Enable the read-write control port that selector output end links to each other with corresponding described writing; And
The read/write address port that links to each other with described control unit; And
Choose the minimum value unit, have one with front-end processing unit the output input that directly links to each other and (L-1) the individual input that links to each other with described (L-1) individual full duplex dual port RAM output, and under the control of described control unit, the time-delay power spectrum of input is chosen minimum value operation.
5. device as claimed in claim 4, it is characterized in that, described control unit by control each write enable selector enable select signal to select to write the full duplex dual port RAM of time-delay power spectrum, and select it is carried out the address of read-write operation by the read/write address port of controlling each full duplex dual port RAM.
6. as any described device among the claim 3-5, it is characterized in that described multi-path judging threshold value generation unit comprises:
Accumulator is used for the energy value of new each phase place of time-delay power spectrum of minimum value filter unit output is added up;
Divider, be used for accumulation result with described accumulator divided by the phase place sum to obtain the average energy value of this time-delay power spectrum; And
Adder is used for the average energy value is obtained the multi-path judging threshold value mutually with a predefined constant.
7. as any described device among the claim 3-5, it is characterized in that the quantity and the described predefined constant that generate the used some time-delay power spectrum of new time-delay power spectrum are determined by emulation experiment.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB021374635A CN100337415C (en) | 2002-10-16 | 2002-10-16 | Multipath searching method and apparatus for CDMA communication system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB021374635A CN100337415C (en) | 2002-10-16 | 2002-10-16 | Multipath searching method and apparatus for CDMA communication system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1490963A CN1490963A (en) | 2004-04-21 |
| CN100337415C true CN100337415C (en) | 2007-09-12 |
Family
ID=34147041
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB021374635A Expired - Fee Related CN100337415C (en) | 2002-10-16 | 2002-10-16 | Multipath searching method and apparatus for CDMA communication system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN100337415C (en) |
Families Citing this family (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100396157C (en) * | 2005-03-03 | 2008-06-18 | 华为技术有限公司 | Method for building transmission link in softer handover |
| CN1925470B (en) * | 2005-08-29 | 2011-03-02 | 中兴通讯股份有限公司 | Multi-path judging method for time-division duplex mobile communication system |
| CN100407872C (en) * | 2005-11-28 | 2008-07-30 | 华为技术有限公司 | Method for confirming multi-path location by different-frequency hard handoff in base station |
| CN1863408B (en) * | 2006-06-12 | 2010-05-12 | 北京天碁科技有限公司 | Method and system for implementing common frequency measurement in TD-SCDMA system |
| CN100396143C (en) * | 2006-08-09 | 2008-06-18 | 华为技术有限公司 | Method and device for processing transmission time delay in wide shrouding |
| CN1921324B (en) * | 2006-09-18 | 2010-08-11 | 北京北方烽火科技有限公司 | Multipath searching method for code division multiple access communication system |
| CN101662310B (en) * | 2009-09-30 | 2012-11-28 | 中兴通讯股份有限公司 | Noise path selection method and device thereof |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1182986A (en) * | 1996-08-23 | 1998-05-27 | Ntt移动通信网株式会社 | RAKE receiver |
| JP2000022664A (en) * | 1998-06-29 | 2000-01-21 | Toshiba Corp | Rake receiver |
| JP2001251215A (en) * | 2000-03-03 | 2001-09-14 | Matsushita Electric Ind Co Ltd | Method and circuit for detecting rake synthesis path |
| JP2002057603A (en) * | 2000-08-08 | 2002-02-22 | Clarion Co Ltd | Ds-cdma system rake receiver |
-
2002
- 2002-10-16 CN CNB021374635A patent/CN100337415C/en not_active Expired - Fee Related
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1182986A (en) * | 1996-08-23 | 1998-05-27 | Ntt移动通信网株式会社 | RAKE receiver |
| JP2000022664A (en) * | 1998-06-29 | 2000-01-21 | Toshiba Corp | Rake receiver |
| JP2001251215A (en) * | 2000-03-03 | 2001-09-14 | Matsushita Electric Ind Co Ltd | Method and circuit for detecting rake synthesis path |
| JP2002057603A (en) * | 2000-08-08 | 2002-02-22 | Clarion Co Ltd | Ds-cdma system rake receiver |
Also Published As
| Publication number | Publication date |
|---|---|
| CN1490963A (en) | 2004-04-21 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN1299199A (en) | Code multiplex system and operation method having improved signal catching and processing | |
| US7050484B2 (en) | Method of detecting path timings and CDMA receiving apparatus using the same | |
| US6173008B1 (en) | Rake receiver for reducing hardware consumption and improving search performance | |
| CN1329789A (en) | Channel estimator with variable number of taps | |
| CN100337415C (en) | Multipath searching method and apparatus for CDMA communication system | |
| CN1183182A (en) | Receiving method and a receiver | |
| CN1254033C (en) | Multi-path searching method and apparatus | |
| CN100459474C (en) | Multipath searching method and device in CDMA system | |
| CN1204695C (en) | Multipath selection deciding method and apparatus for Rake receiver | |
| CN1317893A (en) | Multi-path detecting circuit and system | |
| CN1312620A (en) | Ruiker receiver with low-pass filter | |
| CN1318922A (en) | Demodulating device and method for mobile communication | |
| US7804810B2 (en) | Circuit, method, and program in a CDMA communication system for quickly tracking a stable path | |
| EP1118177A1 (en) | Spread spectrum multipath combining subsystem and method | |
| CN100456662C (en) | A Multipath tracing method and apparatus for CDMA communication system | |
| CN1536773A (en) | Self-adaptive balancer | |
| CN1235363C (en) | Multipath tracking method and device | |
| CN1310442C (en) | Transmission power control circuit using W-CDMA method | |
| EP1339172A1 (en) | Rake receiver apparatus and receiving method | |
| CN1369982A (en) | CDMA mobile communication demodulating circuit and related demodulating method | |
| CN101183881A (en) | Multipath search method and apparatus, signal reception processing method and Rake receiver | |
| CN1303839C (en) | Method and device for reducing sum of calculation for searching in zones and increasing accuracy of calculation | |
| CN1235364C (en) | A multipath search method and apparatus using two layer filtration process | |
| CN1783760A (en) | Peak value searching and arranging device for energy signal | |
| CN1155188C (en) | Multiple user testing method based on removal of interference |
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 | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20070912 Termination date: 20201016 |