Controlling the Performance of Mdpsk in Bad Scattering Channels

This paper describes a modification of the conventional M-ary Differential Phase Shift Keying MDPSK scheme. This method reduces the number of phases which improves the performance of the system by applying a mathematical method from the combinatorial theory called Balanced Incomplete Block Design BIB-design. It is a coding modulation technique in which the signal is represented by a set of phases selected and controlled by the encoder. Each block is transmitted serially or in parallel with equal energy.