Analysis and Design of Interleavers for Iterative Multiuser Receivers In Coded CDMA Systems (original) (raw)
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Analysis and design of interleavers for CDMA systems
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The high-speed data services supported by the 3G mobile systems have claimed the usage of an efficient channel coding technique. Hence, powerful error correcting codes known as Turbo Codes" have been adopted for the Universal Mobile Telecommunications Systems (UMTS). As a crucial component in the turbo-code structure, the turbo-code interleaver is believed to have a key role in its outstanding performance. In this paper, we propose a turbo-code interleaver design algorithm for UMTS. Computer simulations are used to compare the performance of the proposed interleaver to that of the UMTS standard interleaver. Simulation results show that the proposed turbo-code interleaver has a better performance in both additive white Gaussian noise (AWGN) and Rayleigh fading channels.
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The performance of a Turbo code depends on the interleaver design. There are two major criteria that can be considered in the design of an interleaver. Distance spectrum properties of the code and the correlation of the extrinsic information with the input data are the two major criteria in designing an interleaver. This paper describes a new interleaver design based on these two criteria. Simulation results compare the new interleaver design to different existing interleavers. The distance spectrum properties of the Turbo code are compared for different interleaver choices. A new solution to the interleaver edge effects is proposed here.
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Performance of iterative multiuser receiver for turbo-coded DS-CDMA
The 57th IEEE Semiannual Vehicular Technology Conference, 2003. VTC 2003-Spring., 2003
Abstract-In this paper, a low complexity iterative multiuser receiver is analyzed for a turbo-coded CDMA system. The receiver includes a soft multiuser detector and the decoders for users. The simulation considers an uplink asynchronous transmission over a correlated frequency ...