Optimum multiuser detection for MC-CDMA systems using sphere decoding
نویسنده
چکیده
The Maximum Likelihood joint detection of all users in a Multi-Carrier Code Division Multiple Access (MCCDMA) system has a prohibitive complexity, growing exponentially with the number of users, when it is performed using an exhaustive search. In this paper, a novel ML multiuser detection algorithm is proposed, whose complexity is a polynomial function of the number of users and is independent of the modulation size. The MC-CDMA system is modelled using a sphere packing lattice representation and an efficient lattice decoder, called the sphere decoder, is applied to jointly detect all users. Simulation results are proposed up to 64 users transmitting 16-QAM symbols.
منابع مشابه
Optimum and sub-optimum multiuser detection based on sphere decoding for multi-carrier code division multiple access systems
When performed using an exhaustive search, the Maximum Likelihood (ML) joint detection of all users in a MultiCarrier Code Division Multiple Access (MC-CDMA) system has a prohibitive complexity, growing exponentially with the number of users and the number of bits in each modulation symbol. An ML multiuser detection algorithm has recently been proposed, with a complexity growing polynomially wi...
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تاریخ انتشار 2002