Modeling and analysis of a digital portable communications channel with time delay spread

A general model that combines a convenient mathematical representation and a physically meaningful formulation is proposed to analyze and simulate a communications channel in a multipath radio propagation environment. A multipath radio channel can be represented by a time-varying impulse response h(τ;t), which is a complex Gaussian random process for received waveform at delay τ, and the power delay profile is equivalent to the probability density function of τ. Correlation functions of channel impulse response are derived for a general model. Application of this model to a digital portable communications system leads to two bit-error-rate bounds, which can be used to estimate the maximum operable data rate. Some results from a computer simulation are also shown for comparison.