Title :
Performance of Variable Rate and Variable Power MQAM System Based on Bit Error Rate and Channel Estimates
Author :
Ong, L.T. ; Shikh-Bahaei, M. ; Chambers, J.A. ; Lambotharan, S.
Author_Institution :
Center of Digital Signal Process., Cardiff Univ.
Abstract :
We consider the effect of an imperfect channel estimate on a variable rate and variable power (VRVP) multilevel quadrature amplitude modulation (MQAM) system, where the transmit power and data rate are varied relative to the estimate of the received signal. Based on the VRVP-MQAM system operating over a Rayleigh flat-fading channel, we derive a bit error rate (BER) estimator using a maximum aposteriori (MAP) estimation approach. We apply the BER estimator to the VRVP-MQAM system, and thereby derive and obtain system expressions which are applicable to any channel estimation technique. In addition, the resulting formulations are also useful for analyzing the effect of channel state information (CSI). Consequently, we derive and obtain an optimal solution for our proposed system and generate numerical results to compare the variations of system performance with imperfect CSI
Keywords :
Rayleigh channels; channel estimation; error statistics; maximum likelihood estimation; quadrature amplitude modulation; CSI; MAP; Rayleigh flat-fading channel; VRVP-MQAM system; bit error rate; channel estimation; channel state information; maximum aposteriori estimation; multilevel quadrature amplitude modulation; variable rate-variable power system; Amplitude estimation; Bit error rate; Channel estimation; Channel state information; Delay estimation; Fading; Performance analysis; Power system modeling; Signal analysis; Transmitters;
Conference_Titel :
Communications, Circuits and Systems Proceedings, 2006 International Conference on
Conference_Location :
Guilin
Print_ISBN :
0-7803-9584-0
Electronic_ISBN :
0-7803-9585-9
DOI :
10.1109/ICCCAS.2006.284902
