Digitized speech transmission through VHF FM repeaters

This paper presents a study of digitized speech transmission through existing VHF FM repeaters. The basic configuration of digitized speech transmission through FM repeaters is considered and test apparatus for performance measurements of the single repeater radio system in the analog and digital mode of operation is described. The results of performance measurements reported here include 1) receiver sensitivity in the analog and digital mode of operation versus RF signal level at the repeater input, and 2) bit error rate (BER) curves as functions of RF signal levels at the repeater and receiver inputs.