Estimation of the hysteresis value for handover decision algorithms using Bayes criterion

Abstract

In mobile radio communications, inter-cell handover is the process whereby a call in progress is maintained while the mobile unit passes through different cells. Current handover decision algorithms compare the difference between the received signal strengths from different base-stations to a hysteresis value. The proposed paper is a contribution towards an optimal estimation of the hysteresis value using Bayes criterion. An expression of the threshold value h is derived in terms of the standard deviation a of the log-normal shadowing affecting the received signals and the ratio /spl eta/ between the a priori probability of handover and probability of no handover. The performance of the handover decision algorithm is evaluated in terms of the probability of false alarm, or probability of unnecessary handover, and probability of detection, or probability of successful handover.