Performance comparison of DS-BPSK and DS-QPSK CDMA systems

QPSK (quadrature phase shift keying) has been known to be a bandwidth efficient modulation format. The performances of DS-BPSK (direct sequence binary phase shift keying) and DS-QPSK (direct sequence quadrature phase shift keying) modulation formats in a CDMA (code division multiple access) environment are compared in this study to see if this efficiency is preserved under the above conditions. This comparison study includes the effects of bandpass filtering which is not found in current literature. Parameters of interest are the BER (bit error rate) and the capacity supported.