Hilbert Transform Applications in Asynchronous Demodulation for Real Zero Single Sideband Signals in Mobile Radio Path

Abstract

This paper presents asynchronous demodulation methods without the threshold effect for a single sideband (SSB) with reduced carrier signal propagating through mobile radio paths. After an SSB with reduced carrier signal is converted into real zero SSB (RZ SSB) signals in a receiver, the relation of a Hilbert transform pair plays the main role in obtaining its practically perfect demodulation performance using DSP (Digital Signal Processing) processors. The asynchronous demodulation method, first developed in this study, is indispensable for supporting ‘burst mode transmission’ using SSB technology for voice/digital data communications with an ITU-T (International Telecommunication Union Telecommunication Standardization Sector) voiceband modem (MOdulator-DEModulator).