Outage Probabilities of a MIMO Scheme in Shadowed Fading Channels with Micro- and Macrodiversity Reception

Abstract

A compound probability density function (pdf) model is used for the outage analysis of a multiple input multiple output (MIMO) scheme operating in shadowed fading channels. Instead of the lognormal pdf, the compound pdf uses a gamma distribution to account for shadowing, leading to a closed form expression for the pdf of the signal-to-noise ratio in a shadowed fading channel. While the mitigation of short term fading is achieved through the use of multiple transmitters and multiple receivers, the shadowing is mitigated with macrodiversity using two base stations. Taking into account the fact that shadowing has a larger correlation distance, the two base stations are treated to have nonzero correlation. It is shown that the expression for the outage probability in a MIMO scheme operating in shadowed fading channels can be written in a simple form eliminating the need for numerical evaluation of double integrals. Results demonstrate the usefulness of the approach for the analysis of MIMO schemes.