A Study On The Performance Of DSTF Codin And M-ary Orthogonal Signaling In Cooperative Communication Systems

When the channel changes rapidly, it is difficult to estimate channel state information (CSI) accurately. Differential space-frequency group codes (DSFC) and Differential unitary space-time-frequency (DUSTF) codes do not require CSI. Compared with coherent detection, the application of differential detection loses3dB performance. Multiple-symbol differential detection (MSDD) can narrow the performance gaps between differential detection and coherent detection. Compared with the Rayleigh distribution, Nakagami distribution is the better-fit distribution for obtaining experimental data with great variability. Therefore, this paper investigates the error performance of DSFC and DUSTF coded multiple-input multiple-output (MIMO)-orthogonal frequency division multiplexing (OFDM) systems with MSDD in frequency-selective Nakagami fading channels.M-ary orthogonal signalings can be widely applied to power-limited wireless communication systems. By sharing the antennas of mobile terminals, cooperative diversity can improve the transmission reliability of information, and combat the adverse impacts of multipath fading. Therefore, this paper investigates the error performance of decode-and-forward (DF) cooperative communication systems with maximal ratio combining (MRC) and coherent M-ary orthogonal signaling modulation in flat Nakagami fading channels.Chapter1presents a brief review of differential space-frequency (DSF) coding, differential space-time-frequency (DSTF) coding, the performance analysis of M-ary orthogonal signaling in fading channels, and several common system models and protocols of cooperative communication.Chapter2investigates the error performance of DSFC coded MIMO-OFDM system in frequency-selective Nakagami fading channels, uses equispaced subcarrier grouping DSFC coded scheme, and derives the expression for MSDD decoding algorithm of DSFC. Simulation results show that the error performance of DSFC coded MIMO-OFDM system can be improved by applying MSDD.Chapter3investigates the error performance of DUSTF coded MIMO-OFDM system in frequency-selective Nakagami fading channels, analyzes and derives MSDD decoding algorithms of different DUSTF codes. Simulation results show that the error performance of DUSTF coded MIMO-OFDM system can be improved by increasing the channel fading parameters or extending the observation interval.Chapter4derives the exact closed-form expressions for the average symbol error rate (SER) and bit error rate (BER) of coherent M-ary orthogonal signaling for DF single relay cooperative system, dual-hop single relay cooperative system, and relay selection cooperative system with MRC in flat Nakagami fading channels. The numerical results show that the error performance of DF cooperative communication systems can be improved by increasing the number of the receiving antennas at the relay node and the destination node or the dimensions of M-ary orthogonal signaling.Chapter5finishes the paper with concluding remarks.