An Application of a Semi Markov Model in Predicting the Fading Occurrences in Wireless Communication Channels

Abstract

The most frustrating and troublesome issue in wireless communication is fading. Estimating thefading occurrence for the design of greatly reliable communication link is crucial. In this paper,we present a novel mathematical method for predicting the future signal fading on the basis ofcurrent and past data. The application of a Semi Markov Model as a generalization of the MarkovModel is discussed for predicting the deep fading occurrence probabilities of the receivedenvelope in wireless communications channels. This flexible model is given for assessing thesystem performance with the envelope correlation. 142 deep fading data whose amplitudes arelower than a mean of the amplitudes which occurred in a typical wireless system with the Jakesfiltering are considered. The transition probability matrix and the holding time mass functionsare calculated for the next 1 to 21 unit times. One unit time is regarded as the inverse of samplingfrequency; moreover, the core matrix and the cumulative probability distribution of the waitingtime are obtained. Calculating the interval transition probabilities for Amplitude to Amplitudetransition for these deep fades demonstrates the forecasting occurrence probabilities in the futureand the possibility of forecasting the fading occurrences in dimensions of time and amplitude.