Hybrid macro- and generalized selection combining microdiversity in lognormal shadowed rayleigh fading channels

The performance of hybrid microdiversity, in the form of generalized selection combining (GSC), and macrodiversity is presented for lognormal shadowed Rayleigh fading channels. The GSC-augmented macrodiversity consists of K ports in a cell, each port carrying N microscopic diversity antennas. The macroscopic diversity involves selecting the port with the highest long-term local mean SNR among the K ports, and the GSC uses n strongest signals of the N branch received signals from that port for processing. We derive analytical expressions for error probability and outage for systems employing this hybrid scheme. The expressions are valid for any configurations of K,N, n. In microcell systems substantial correlation could exist among the ports in contrast to macrocell; results are also shown for correlated lognormal shadowed Rayleigh channels. Extensive simulations are carried out to validate the analytical expressions derived.