Performance Analysis of MF-TDMA Multi-Carrier Demultiplexer/Demodulators (MCDDs) in the Presence of Critical Degrading Factors

Two typical MCDD (multi-carrier demultiplexer/demodulator) architectures, M-MCD (multistage multicarrier demultiplexer) and PPF (polyphase FFT) suitable for multimedia service via the on-board processing (OBP) satellite, are analytically modeled and their error performances are numerically evaluated in the presence of five degrading factors including: narrow-band AWGN, carrier frequency offset, phase error, ISI and quantization error. Cumulative effects of these factors on the BERs of the two different MCDD structures are also assessed and compared for possible tradeoff under MF-TDMA (Multi-Frequency Time Division Multiplex Access) scheme using QPSK modulation. Results show that both architectures are commonly vulnerable to most degrading factors. However, combined effect of phase error with AWGN is more critical to M-MCD than PPF. In addition, PPF method proves to be more sensitive to quantization error than M-MCD. When all five degrading factors are considered, MCDD using PPF method exhibits better BER performance than that of M-MCD, especially when carrier phase error is significant.