... SNR (dB) Q -OFDMA P = 64 Q -OFDMA P = 16 OFDMA1 OFDMA2 OFDMA3 Figure 5: BER of uncoded systems with BPSK modulation under CM2 channel model, where N = 256 the system performance and Q -OFDMA is inferior ... 16 SNR (dB) Q -OFDMA, ZF, no iteration Q -OFDMA, MMSE, no iteration Q -OFDMA, MMSE, iterations Q -OFDMA, MMSE, iterations Q -OFDMA, FD-DFE Figure 6: BER performance comparison between Q -OFDMA systems ... = 1, the QOFDMA system becomes the conventional OFDMA system, which outperforms the Q -OFDMA system (1 < P < N) only in low SNR range This problem can be solved by utilizing advanced receivers,...