Noise immunity of digital information transmission in a radio communication system by DQPSK signals with frequency hopping spread spectrum in the partial-band jamming noise.

Abstract

The article deals with an algorithm for noncoherent reception of signals with Differential Quadrature Phase Shift Keying (DQPSK) using their weight processing for radio communication systems (RCS) with Frequency-hopping spread spectrum (FHSS) under Partial-band jamming noise (concentrated in the interference spectrum). Numerical calculations of bit/symbol error probability in the reception of DQPSK signals with a symbol-by-symbol frequency hopping are presented, as well as the results of modelling the considered reception algorithm for a radio communication system with an intra-symbol frequency hopping to study the noise immunity of receiving a DPQSK signal in the considered mode. It is shown that for not too large signal-to-jamming ratios when only a part of the operating frequencies is clogged by this noise, the noncoherent reception algorithm with weight processing provides higher noise immunity than the symbol-by-symbol frequency-hopping algorithm.