Signal transmission over channels with time-varying random delays

Many communication channels can best be studied when they are modeled as linearly time varying systems, such that their impulse response is itself a random process. An important class of such channels that having pure delay is considered, and the problem of signal transmission over such channels is analyzed. In a pure delay channel the input signal suffers a time varying and possibly random delay on passage from the transmitter to the receiver such that an impulse applied at time t produces a weighted impulse at the output at time t+theta(t), where theta(t) is a delay function which characterizes the channel completely. Several important applications are found in satellite communications, tropospheric scatter, radar and sonar systems, random path networks, speaker recognition studies, etc. These systems can be modelled as pure delay channels.