Low complexity linear iteraction multiple users detecting device and method
A technology of multi-user detection and linear iteration, which is applied in the field of linear iterative multi-user detection devices and multi-user detection devices in direct sequence code division multiple access systems, can solve the difficulty of solving the inverse of the correlation matrix R and the difficulty of computational complexity Acceptance, Difficulty, etc.
Patent Information
- Authority / Receiving Office
- CN · China
- Current Assignee / Owner
- Publication Date
- 2007-01-24
- Estimated Expiration
- Not applicable · inactive patent
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Abstract
Description
Technical field:
[0001] The present invention relates to a low-complexity linear iterative multi-user detection device and method, belonging to the field of digital communication using electromagnetic wave technology, and in particular to a device and method for multi-user detection in a Direct Sequence Code Division Multiple Access (DS-CDMA) system, These devices and methods can eliminate the multiple access interference (MAI) existing in the DS-CDMA system in real time. Background technique:
[0002] In a CDMA communication system, the main factors restricting system performance include co-channel interference and intersymbol interference. Inter-symbol interference restricts the communication rate of the system, which is mainly suppressed by equalization or diversity technology; it is mainly caused by multiple access interference (MAI) such as mobile stations in the same cell, same-frequency base stations or mobile stations in adjacent cells, and other communication system...
Examples
Embodiment Construction
[0070] The technical solution of the present invention will be further described through specific implementation below.
[0071] Using Matlab simulation software to simulate, the simulation system is a synchronous / asynchronous DS-CDMA system, AWGN channel, BPSK modulation, carrier phase is 0, and a pseudo-random sequence with a length of 10 is used to spread spectrum. The analysis is carried out from three aspects of bit error rate, anti-"near and far" effect and computational complexity. Assume that user 1 is the expected user and the number of users is 10.
[0072] Step 1: At the receiving end, a vector of 10 matched filter bank outputs is available:
[0073] y=RBb+N
[0074] Among them, R=S·S H , the size of the correlation matrix R is 10×10, which represents the correlation value between two codewords.
[0075] Step 2: For the MMSE multi-user detector, select the adaptive adjustment factor α, the measured noise power σ 2 and signal amplit...