Delay spread statistics in vicinity of same-frequency repeater

The statistics of the delay spread in a two-path mobile radio environment where every path is subject to log-normal shadowing are derived. The channel profile thus considered consists of two delta functions whose power levels are in addition, correlated. Analytical expressions for the probability density function, the mean and the standard deviation of the resulting delay spread are obtained and compared with simulation results     

Delay-spread considerations of same-frequency repeaters in widebandchannels

In current analog cellular systems, same-frequency repeaters are very often used as gap fillers. With digital wideband systems, the use of a repeater, with its inherent group delay added to the differential propagation delay, may yield a degradation in the performance in view of the resulting delay spread. An approach to estimate the statistics of the delay spread when each link is subjected to lognormal shadowing and each channel's power-delay profile follows an exponential decay is presented. Expressions for the cumulative density function (CDF), mean value, mean-square value, and standard deviation for the RMS delay spread are derived, and their accuracy is verified through simulation