CN1242577C - Partial interference counteracting method and device for upstream channel of wideband CDMA system - Google Patents
Partial interference counteracting method and device for upstream channel of wideband CDMA system Download PDFInfo
- Publication number
- CN1242577C CN1242577C CN 02111500 CN02111500A CN1242577C CN 1242577 C CN1242577 C CN 1242577C CN 02111500 CN02111500 CN 02111500 CN 02111500 A CN02111500 A CN 02111500A CN 1242577 C CN1242577 C CN 1242577C
- Authority
- CN
- China
- Prior art keywords
- dpcch
- signal
- unit
- demodulation
- user
- 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 - Lifetime
Links
Images
Landscapes
- Noise Elimination (AREA)
Abstract
The present invention relates to a partial interference cancellation method and a device for uplink channels of a wideband code division multiple access system. The method comprises the steps that baseband input signals are outputted by two channels, namely, a first channel and a second channel; delay signals are outputted after first channel signals are delayed; the second channel combines the outside world to input each multi-path information and a scrambling code of each user for demodulating a DPCCH; after delayed, a demodulation result combines the outside world to input the scrambling code of each user for countermodulation; then, a result of the countermodulation is interpolated for obtaining data having the same velocity with the adoption rate; the delay signals outputted by the first channel is subtracted from the data to output signals after the signal to noise ratio is increased. The technical scheme is adopted for carrying out the countermodulation and partial interference cancellation by the demodulation result of the DPCCH. Simultaneously, the countermodulation and the partial interference cancellation are only carried out to the DPCCH, and thus, the operation amount can be reduced, and thereby, the requirements of the system for hardware equipment can be reduced for reaching the purpose of cost reduction.
Description
(1) technical field
The present invention relates to up channel is handled in WCDMA (Wideband Code Division Multiple Access (WCDMA)) system method and device.
(2) background technology
In CDMA (code division multiple access) system,, can cause that multiple access disturbs (MAI) because intersymbol is non-orthogonal.The multiple access interference-limited capacity of system.Existing system generally adopts RAKE (multipath) receiver, but can only solve the problem that multipath disturbs, and can not reduce multiple access effectively and disturb.Be to eliminate the influence that multiple access disturbs, people have proposed to utilize other user's Given information to remove to eliminate the multi-user test method that multiple access disturbs, and wherein a kind of is to deduct Interference Detection mutually.Deducting mutually in the Interference Detection, carry out secondary or repeatedly demodulation, promptly at first go out all users' of this sub-district DPDCH (DPCH data channel) and DPCCH (DPCH control channel) signal according to total receiving signal demodulation, DPDCH signal for a specific user, other all channels all are that multiple access disturbs, therefore in total received signal, deduct the multiple access interference, again the signal that obtains be carried out demodulation, thereby get the higher information of signal to noise ratio.This demodulation, removal multiple access disturb and the process of demodulation again can repeat repeatedly, because the multiple access interference all is different concerning each specific DPDCH channel, therefore this method will demodulate the calculating that a DPDCH channel need carry out complexity to all subscriber signals of this sub-district, if always total N DPDCH channel, this calculating is except result partly can share, remainder will repeat N time, make the scale of calculating quite complicated.
Above-mentioned interference cancellation method is because the algorithm complex height can increase a lot of hardware facilities, thereby improve the cost of system.
(3) summary of the invention
The object of the present invention is to provide a kind of partial interference counteracting method and device of upstream channel of wideband CDMA system, thereby reduce the hardware size of system, the cost of reduction system.
The partial interference cancellation device of a kind of upstream channel of wideband CDMA system provided by the present invention, this device is to carry out work under clock signal of system control, it is characterized in that it comprises: data interface unit, receive user's baseband signal of this sub-district, and this signal is done two-way output; Data buffer storage unit receives one tunnel output signal from data interface unit, the time delay output; DPCCH channel demodulation unit, receive another road output signal from data interface unit, and obtain each user's multipath information and scrambler from the external world, the DPCCH channel of every multipath of all users of sub-district is carried out demodulation, the DPCCH soft-decision symbol after the output demodulation and the time delay information of multipath; DPCCH symbol buffer unit, with the back output of delaying time of the DPCCH soft-decision symbol of the output of DPCCH channel demodulation unit, the symbol of every multipath of each user of output aligns on the DPCCH of system time symbol rank, exports corresponding multidiameter delay information simultaneously; DPCCH symbol and time delay information are read from DPCCH symbol buffer unit in the band spectrum modulation unit, and in conjunction with the extraneous scrambler of importing each user, the DPCCH symbol are carried out band spectrum modulation, export the DPCCH signal after every multipath of each user is modulated; Interpolation unit obtains the DPCCH signal of spreading rate from the band spectrum modulation unit, carry out interpolation according to the needs of data sampling rate, removes the DPCCH signal simultaneously owing to carry out the gain that demodulation brings, and makes its amplitude and carries out former consistent of demodulation; Offset unit is read the data of DPDCH in buffer memory, and deducts from the DPCCH signal of every multipath of all users of interpolation unit acquisition the signal after output signal-to-noise ratio improves.
The present invention also provides a kind of partial interference counteracting method of upstream channel of wideband CDMA system, base-band input signal is done 2 tunnel output, i.e. first, second roads that is:; With the first via signal back output time delayed signal of delaying time; The second tunnel information and the scrambler of importing every multipath of each user in conjunction with the external world carries out demodulation to DPCCH, after delaying time, demodulation result carries out counter modulation in conjunction with the extraneous scrambler of importing each user again, result to counter modulation carries out interpolation then, obtain and the sample rate data of same rate mutually, the time delayed signal that these data are exported by the first via subtracts each other, the signal after output signal-to-noise ratio improves.
Adopt above technical scheme, utilized the DPCCH demodulation result to carry out counter modulation and carry out partial interference cancellation, counter modulation simultaneously and Interference Cancellation only carry out DPCCH, thereby can reduce operand, thereby can reduce system to requirements on hardware equipment, thereby reach the purpose that reduces cost.
(4) description of drawings
Fig. 1 is the flow chart of the inventive method;
Fig. 2 is the schematic diagram of structure of the present invention.
(5) embodiment
As shown in Figure 1, the present invention, the partial interference counteracting method in promptly a kind of Wideband Code Division Multiple Access (WCDMA) up channel is divided into 2 the tunnel with base-band input signal, i.e. first, second road; With the first via signal back output time delayed signal of delaying time; The second tunnel information and the scrambler of importing every multipath of each user in conjunction with the external world carries out demodulation to DPCCH, after delaying time, demodulation result carries out band spectrum modulation in conjunction with the extraneous scrambler of importing each user again, result to band spectrum modulation carries out interpolation then, obtain and the employing rate data of same rate mutually, the time delayed signal that these data are exported by the first via subtracts each other, the signal after output signal-to-noise ratio improves.
As shown in Figure 2, the present invention, the partial interference cancellation device in promptly a kind of Wideband Code Division Multiple Access (WCDMA) up channel, this device are to carry out work under clock signal of system control, it comprises:
Data buffer storage unit 301, the data that data interface unit 101 is sent here are made buffer memory, cache-time comprises the demodulation of finishing the DPCCH channel and calculates all processing times of interference signal, can also comprise and wait for that TFCI (transformat indication) deciphers the needed time, this unit can be realized with memory, I, Q two-way can be stitched together simultaneously to save memory space;
DPCCH demodulating unit 201, base band data that reception data interface unit 101 is sent here and all users' of this sub-district that import from the external world multipath information and scrambler, each bar multipath to all users' of sub-district DPCCH channel carries out demodulation, demodulation can realize with correlator, export the DPCCH channel soft-decision symbol of each bar multipath after the demodulation, export the time delay information of this multipath simultaneously;
DPCCH symbol buffer unit 202, receive the DPCCH channel soft-decision symbol of sub-district each bar multipath of all users and the time delay information of corresponding multipath from DPCCH demodulating unit 201, time delay information and system time according to multipath are determined corresponding stored position, symbol with every multipath of each user of guaranteeing output aligns on the DPCCH of system time symbol rank, and this module is exported every multipath of each user in turn at the DPCCH soft-decision symbol of same symbol on regularly;
DPCCH symbol and time delay information are read from DPCCH symbol buffer unit 202 in band spectrum modulation unit 203, and in conjunction with the extraneous scrambler of importing each user, the DPCCH symbol are carried out band spectrum modulation, export the DPCCH signal after every multipath of each user is modulated;
Claims (2)
1. the partial interference cancellation device of a upstream channel of wideband CDMA system, this device are to carry out work under clock signal of system control, it is characterized in that it comprises:
Data interface unit receives user's baseband I Q signal of this sub-district, and this signal is made two-way export;
Data buffer storage unit receives one tunnel output signal from data interface unit, the time delay output;
DPCCH channel demodulation unit, receive another road output signal from data interface unit, and obtain each user's multipath information and scrambler from the external world, the DPCCH channel of every multipath of all users of sub-district is carried out demodulation, the DPCCH soft-decision symbol after the output demodulation and the time delay information of multipath;
DPCCH symbol buffer unit, with the back output of delaying time of the DPCCH soft-decision symbol of DPCCH channel demodulation unit output, the symbol of every multipath of each user of output aligns on the DPCCH of system time symbol rank, exports corresponding multidiameter delay information simultaneously;
DPCCH symbol and time delay information are read from DPCCH symbol buffer unit in the band spectrum modulation unit, and in conjunction with the extraneous scrambler of importing each user, the DPCCH symbol are carried out band spectrum modulation, export the DPCCH signal after every multipath of each user is modulated;
Interpolation unit obtains the DPCCH signal of spreading rate from the band spectrum modulation unit, carry out interpolation according to the needs of data sampling rate, removes the DPCCH signal simultaneously owing to carry out the gain that demodulation brings, and makes its amplitude and carries out former consistent of demodulation;
Offset unit, sense data in the data buffer storage unit, and deduct the DPCCH signal of every the multipath of all users that obtains from interpolation unit, the signal after output signal-to-noise ratio improves.
2. the partial interference counteracting method of a upstream channel of wideband CDMA system is characterized in that: base-band input signal is done 2 tunnel output, i.e. first, second roads; With the first via signal back output time delayed signal of delaying time; The second tunnel information and the scrambler of importing every multipath of each user in conjunction with the external world carries out demodulation to DPCCH, after delaying time, demodulation result carries out counter modulation in conjunction with the extraneous scrambler of importing each user again, result to counter modulation carries out interpolation then, obtain and the sample rate data of same rate mutually, the time delayed signal that these data are exported by the first via subtracts each other, the signal after output signal-to-noise ratio improves.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 02111500 CN1242577C (en) | 2002-04-26 | 2002-04-26 | Partial interference counteracting method and device for upstream channel of wideband CDMA system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 02111500 CN1242577C (en) | 2002-04-26 | 2002-04-26 | Partial interference counteracting method and device for upstream channel of wideband CDMA system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1453946A CN1453946A (en) | 2003-11-05 |
| CN1242577C true CN1242577C (en) | 2006-02-15 |
Family
ID=29256800
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 02111500 Expired - Lifetime CN1242577C (en) | 2002-04-26 | 2002-04-26 | Partial interference counteracting method and device for upstream channel of wideband CDMA system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN1242577C (en) |
Families Citing this family (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100342664C (en) * | 2004-06-08 | 2007-10-10 | 华为技术有限公司 | CDMA up special physical information channel multi-user receiving apparatus |
| CN101908907B (en) * | 2005-01-24 | 2012-07-25 | 株式会社Ntt都科摩 | Mobile communication terminal and method for controlling activation of multi-path interference removing apparatus |
| US7688925B2 (en) * | 2005-08-01 | 2010-03-30 | Ati Technologies, Inc. | Bit-deskewing IO method and system |
| CN1929353B (en) * | 2005-09-09 | 2012-04-25 | 展讯通信（上海）有限公司 | Method and device for channel estimation of common-frequency cell |
| CN100411318C (en) * | 2005-11-11 | 2008-08-13 | 华为技术有限公司 | Method for carrying out parallel interference compensation based on control channel |
| CN101494506B (en) * | 2009-03-10 | 2012-05-23 | 北京科技大学 | Circuit for capturing running water structure underwater sound spread-spectrum communication bandpass signal |
| CN102006099B (en) * | 2009-08-31 | 2013-12-25 | Tcl集团股份有限公司 | Iterative combined detection and decoding method with interference elimination and system thereof |
| WO2011079470A1 (en) * | 2009-12-31 | 2011-07-07 | 中兴通讯股份有限公司 | Method and apparatus for cancelling interference |
| CN102088787B (en) * | 2010-12-10 | 2014-08-20 | 中兴通讯股份有限公司 | Method and system for demodulating uplink data channel in wideband code division multiple access system |
| CN103684725A (en) * | 2013-12-03 | 2014-03-26 | 深圳市华星光电技术有限公司 | Method for avoiding interference in pulse signal and terminal applicable thereto |
| CN110149286A (en) * | 2015-05-11 | 2019-08-20 | 蒋华丽 | The signal processing method of the raising signal-to-noise ratio of digital communication under additive noise environment |
-
2002
- 2002-04-26 CN CN 02111500 patent/CN1242577C/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| CN1453946A (en) | 2003-11-05 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN100379166C (en) | RAKE Receiver in CDMA system, with space-time transmitting diversity | |
| CN1143449C (en) | Combining sub-chip resolution samples in fingers of a spread-spectrum rake receiver | |
| CN1242577C (en) | Partial interference counteracting method and device for upstream channel of wideband CDMA system | |
| EP1774670B1 (en) | Use of adaptive filters in cdma wireless systems employing pilot signals | |
| CN1192505C (en) | CDMA receiver that shares tracking device among multiple Rake branches | |
| US20100040035A1 (en) | Interference canceling CDMA mobile station receiver | |
| JPH10504143A (en) | Direct sequence CDMA coherent uplink detector | |
| EP0749215A2 (en) | Multipath diversity reception in a spread spectrum communication system | |
| CN101278489A (en) | A method and apparatus for received communication signal processing | |
| CN100411318C (en) | Method for carrying out parallel interference compensation based on control channel | |
| JPH10336072A (en) | Rake receiver for direct diffusion cdma transmission system | |
| CN1711708B (en) | Method and apparatus for rake combining based upon signal to interference noise ratio | |
| CN1615598B (en) | Low complexity multiuser detector and method for generating de-spread sequence for user in CDMA reciever system | |
| JP2006054900A (en) | Chip equalizer for spread spectrum receiver, noise factor computation method and filter coefficient determination method used in the chip equalizer | |
| CN101379719B (en) | Determination of active spreading codes and their powers | |
| Lingwood et al. | ASIC implementation of a direct-sequence spread-spectrum RAKE-receiver | |
| CN103825847B (en) | A kind of channel disturbance offsets method, apparatus and base station | |
| CN102790628B (en) | Acquisition method and device for multipath code phase based on broadcast positioning signal | |
| CN1312620A (en) | Ruiker receiver with low-pass filter | |
| CN1879338A (en) | Multi-path search method of CDMA communication system | |
| CN100392992C (en) | Receiving apparatus | |
| CN100438385C (en) | Baseband receiving synchronous acquiring method and apparatus for CDMA system | |
| JP4176522B2 (en) | Interference reduction device | |
| CN101036402A (en) | Baseband processing method based on double sampling | |
| KR20070061694A (en) | Method and apparatus for channel estimation through multiple access interference cancellation in wireless telecommunication basestation system |
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 | ||
| C56 | Change in the name or address of the patentee |
Owner name: SHANGHAI ALCATEL-LUCENT CO., LTD. Free format text: FORMER NAME: BEIER AERKATE CO., LTD., SHANGHAI Owner name: BEIER AERKATE CO., LTD., SHANGHAI Free format text: FORMER NAME: BELL CO.,LTD., SHANGHAI |
|
| CP01 | Change in the name or title of a patent holder |
Address after: 201206 Pudong New Area Jinqiao Export Processing Zone, Nanjing Road, No. 388, Shanghai Patentee after: ALCATEL-LUCENT SHANGHAI BELL Co.,Ltd. Address before: 201206 Pudong New Area Jinqiao Export Processing Zone, Nanjing Road, No. 388, Shanghai Patentee before: Shanghai Bell Alcatel Co.,Ltd. Address after: 201206 Pudong New Area Jinqiao Export Processing Zone, Nanjing Road, No. 388, Shanghai Patentee after: Shanghai Bell Alcatel Co.,Ltd. Address before: 201206 Pudong New Area Jinqiao Export Processing Zone, Nanjing Road, No. 388, Shanghai Patentee before: Shanghai Bell Co.,Ltd. |
|
| CP01 | Change in the name or title of a patent holder | ||
| CP01 | Change in the name or title of a patent holder |
Address after: 201206 Pudong New Area Jinqiao Export Processing Zone, Nanjing Road, No. 388, Shanghai Patentee after: NOKIA SHANGHAI BELL Co.,Ltd. Address before: 201206 Pudong New Area Jinqiao Export Processing Zone, Nanjing Road, No. 388, Shanghai Patentee before: ALCATEL-LUCENT SHANGHAI BELL Co.,Ltd. |
|
| CX01 | Expiry of patent term | ||
| CX01 | Expiry of patent term |
Granted publication date: 20060215 |