Noise immunity of discrete-message transmission in the case of selective frequency-diversity

The paper analyzes the noise immunity of discrete-signal transmission in radio channels with fading which employ the method of frequency-adaptation (selective diversity) for the case of statistically homogeneous independent diversity-branches. Consideration is given to the effects of time lag on adaptation of the transmitter and to the number of frequencies which ensure minimal error-probability during reception. An expression is obtained for this error probability, which enables generalization for nonadaptive systems with selective diversity and for adaptive systems with data transmission at the optimal frequency.