A new demodulation procedure for CDMA systems based on complete complementary codes

Signal design methods for the approximately synchronized CDMA systems based on complete complementary codes have been proposed. It has been shown that both the information transmission rate and the frequency usage rate can be increased in these kinds of CDMA systems. The bit error rate (BER) properties of these systems have been also reported recently. However, it's not been considered sufficiently why bit errors occur. In this paper, we analyze the bit error distribution and discuss the cause of bit errors in these systems. In addition, we propose the effective demodulation scheme to decrease bit errors and compare the BER performances of the proposed method with that of the original demodulation scheme of CDMA systems using complete complementary codes through some numerical simulations.