The New If Combiner for Microwave Radio Relay System

Nowadays, transmission of digital data is rapidly expanding. Especially, the transmission with more bits/Hz and greater hop distance are needed because efficient band use and economy are required. Under these conditions, the noise performance in a microwave radio system is inevitably degraded by fading. Many kind of methods for improving the performance such as the hitless combiner, adaptive equalizer and transversal equalizer have been investigated. In this paper, hitless IF combiner used for space deversity reception is described.