Algorithm Receiving as a Whole Element Wise Decision for Differential Phase Shift Keying π/4-DQPSK in Сhannels with Memory

The article provides the description of the demodulation features for a differential phase shift keying according to the reception algorithm as a whole element decision-making in radio channels with memory. In the considered method of differential phase, there are permitted and prohibited increments of the phase of two adjacent signals transmitted during the symbol transmission period. Such limitations is a source of additional information that can be used in order to reduce the error probability. Computer modeling with imitation of a communication channel with memory was used to evaluate the transmission quality. The reception algorithm as a whole was compared with the demodulation algorithm based on an equalizer. According to the simulation results, the dependences of the error probability on the signal/ noise ratio were observed to demonstrate that the reception algorithm as a whole makes it possible to decrease an error probability than the algorithm with equalizer, starting from a certain signal/noise proportion value.