Concatenated Space-Time Block Coded and Turbo Coded Symbol-by-Symbol Adaptive OFDM and Multi-Carrier CDMA Systems

摘要

1. An uncoded AQAM scheme with optimum switching levels results in constant average BER and attains highest possible average BPS throughput. 2. Space-Time block coding increases diversity gain but it reduces the relative gain of AQAM. 3. Additional turbo convolutional coding results in near error-free performance, achieving 6dB SNR gain at 1 BPS throughput in comparison to the uncoded counterpart. 4. The SNR gain of adatpive MC-CDMA over adaptive OFDM is less than 3dB over W-ATM channel scenario. 5. If the complexity of 2-Tx is not affordable, Adaptive QAM is a good low-complexity solution. For 2-Tx schemes, Adaptive modulation is not necessary.