Design and Implementation of a Low Complexity Multiuser Detector for Hybrid CDMA Systems

Autor: Vittorio Rampa
Jazyk: angličtina
Rok vydání: 2005
Předmět:
Zdroj: Journal of Communications Software and Systems, Vol 1, Iss 1, Pp 42-50 (2005)
Druh dokumentu: article
ISSN: 1845-6421
1846-6079
Popis: In hybrid CDMA systems, multiuser detection (MUD) algorithms are adopted at the base station to reduce both multiple access and inter-symbol interference by exploitingspace-time (ST) signal processing techniques. Linear ST-MUD algorithms solve a linear problem where the system matrix has a block-Toeplitz shape. While exact inversion techniques impose an intolerable computational load, reduced complexity algorithms may be efficiently employed even if they show suboptimal behavior introducing performance degradation and nearfar effects. The block-Fourier MUD algorithm is generally considered the most effective one. However, the block-Bareiss MUD algorithm, that has been recently reintroduced, shows also good performance and low computational complexity comparingfavorably with the block-Fourier one. In this paper, both MUD algorithms will be compared, along with other well known ones, in terms of complexity, performance figures, hardware feasibility and implementation issues. Finally a short hardware description of the block-Bareiss and block-Fourier algorithms will be presented along with the FPGA (Field Programmable Gate Array) implementation of the block-Fourier using standard VHDL (VHSIC Hardware Description Language) design.
Databáze: Directory of Open Access Journals