VOICE TRANSMISSION QUALITY OF MOBILE SATELLITE-COMMUNICATIONS SYSTEMS

Recently, a number of commercial digital mobile satellite communicatio ns systems have become operational, and the introduction of more syste ms is imminent. The voice transmission quality of the Inmarsat-aeronau tical, Inmarsat-M and Inmarsat-B systems was evaluated and compared wi th the quality of the Inmarsat-A analogue communication system on the basis of subjective listener opinion assessments. From this evaluation it can be concluded that, under nominal operating conditions, the cur rent generation of digital mobile systems may offer a perceived perfor mance that surpasses that of the older Inmarsat-A analogue system, at least when measured in terms of transmission quality.