Transmitter macrodiversity in radio fibre microcellular networks

Abstract

Radio-fibre microcellular networks are composed by small-size cells that make use of a fibre optic network for the conveyance of RF signals from a central controller to remote antennae at cellsite. This structure is particularly suitable to accomplish receiver and transmitter macrodiversity since the same RF channel can be transmitted and received through multiple ports, thus providing a large coverage area in which mobiles do not have to switch channels when roaming. This paper investigates the performance of multitransmitter diversity in fading channels, in noise and interference limited conditions. The problem differs from diversity reception in that signal combining is now non-coherent. Results are presented in terms of radio coverage and cochannel reuse efficiency firstly under Rayleigh fading only and secondly in a city street microcell environment. Simulcasting is an effective shadowing counteraction in noise conditions and achieves similar performance to no diversity in interference conditions.