This paper focuses on the performance of the minimum mean-squared error (MMSE) multiuser detector (MUD) in the downlink of direct-sequence code-division multi-ple-access (DS-CDMA) systems. An analytical upper bound on the bit-error probability in frequency-nonse-lective Rayleigh fading channels is derived. This bound is obtained by evaluating the bit-error probability of a linear detector, which is characterised by a reduced complexity with respect to the MMSE. The closeness of this theoretical bound to the ideal MMSE bit-error rate (BER) performance is analysed by simulation in several scenarios, evidencing the performance gain at low signal-to-noise (SNR) with respect to the decorrelator detector. Thus, this receiver can be considered a possible compromise between MMSE and decorrelator detector as far as performance and complexity is concerned.
An Analytical Upper Bound on MMSE Performance Using Approximated MMSE Multiuser Detector in Flat Rayleigh Fading Channels
RUGINI, LUCA;BANELLI, Paolo;CACOPARDI, Saverio
2002
Abstract
This paper focuses on the performance of the minimum mean-squared error (MMSE) multiuser detector (MUD) in the downlink of direct-sequence code-division multi-ple-access (DS-CDMA) systems. An analytical upper bound on the bit-error probability in frequency-nonse-lective Rayleigh fading channels is derived. This bound is obtained by evaluating the bit-error probability of a linear detector, which is characterised by a reduced complexity with respect to the MMSE. The closeness of this theoretical bound to the ideal MMSE bit-error rate (BER) performance is analysed by simulation in several scenarios, evidencing the performance gain at low signal-to-noise (SNR) with respect to the decorrelator detector. Thus, this receiver can be considered a possible compromise between MMSE and decorrelator detector as far as performance and complexity is concerned.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
