Abstract
Code-phase shift keying modulation is a new technology presented recently. It derives from the conventional DSSS system and is modified by employing distinct symbols with distinct code phases of a single periodic m-sequence. According to the length of period and sampling interval of the m-sequence, CPSK can be separated into two kinds: short code sequences and long code sequences. The advantages of using M-ary CPSK is to advance the power efficiency compared to conventional BPSK and advance the bandwidth efficiency by increasing . It also raises the system flexibility by using long code sequences. We will show the analysis about system performance and illustrate the implementation of two methods.