Performance analysis of a multistage quasi-orthogonal minimum output energy multiuser detector for turbo coded CDMA systems in multipath environment

• Main Authors: Abd-El Aziz, M.M., El-Ramly, S.H.
• Format: Conference Proceeding
• Language: English
• Subjects: Applied sciences; Coding, codes; Decoding; Decorrelation; Detection, estimation, filtering, equalization, prediction; Detectors; Exact sciences and technology; Feeds; Information, signal and communications theory; Matched filters; Mean square error methods; Multiaccess communication; Performance analysis; Signal and communications theory; Signal, noise; Systems, networks and services of telecommunications; Telecommunications; Telecommunications and information theory; Transmission and modulation (techniques and equipments); Turbo codes; Viterbi algorithm
• ISSN: 1090-3038; 2577-2465
• DOI: 10.1109/VETECF.2004.1400108

In this paper presents the performance of the multistage quasi-orthogonal minimum output energy (QOMOE) detector for a turbo coded CDMA system. The QOMOE detector minimizes the output variance with respect to the component equivalent to the quasi-orthogonal component to the desired user's signature waveform, then the solution is the linear minimum mean square error (LMMSE) transformation. The multistage QOMOE multiuser detector (MuD) employs maximal-ratio combiner (QOMOE-MRC) for detection of the desired user, and feeds a soft decision Viterbi decoder. A comparison is made among multistage detectors with first stage QOMOE-MRC, matched filter (MF-MRC), decorrelator-MRC, LMMSE-MRC and blind adaptive-MRC detector, in a frequency flat Rayleigh fading channel. Analysis and simulation results show that the multistage QOMOE-MRC has better performance than that of multistage LMMSE-MRC detector.