The BER performance of a quasi-orthogonal minimum output energy multiuser detector for CDMA systems in Nakagami environment

The paper presents the performance of the quasi-orthogonal minimum output energy (QOMOE) detector for a synchronous CDMA system in Nakagami environment. 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 QOMOE receiver employs maximal-ratio combiner (QOMOE-MRC) for detecting the desired user. A comparison is made among QOMOE-MRC, matched filter (MF-MRC), decorrelator-MRC, LMMSE-MRC and blind adaptive-MRC receivers, in a Nakagami channel model. Analysis and simulation results show that the QOMOE-MRC can obtain better performance than that of LMMSE-MRC receiver