Equivalence measurement studies (sections 1-4), volume 1

The report describes the results of an investigation concerned with developing and evaluating concepts for channel quality monitoring of advanced digital data transmission techniques over four fading dispersive channels of interest to military communications: the line-of-sight ground point-to-point microwave relay, troposcatter, satellite ionospheric scintillation, and high-frequency long haul channels. The study emphasis is on a monitoring subsystem called the Media Quality Unit (MQU) which continually estimates long- and short-term error rates for a nondegraded receiver and by comparison with actual error rate as measured by a Performance Monitor Unit (PMU) allows estimation of receiver degradation trends and classification of outages into receiver-, media, or interference-caused. Major effort was devoted to development and analysis of MQU techniques which use the received information-bearing signal alone as a source of channel information since continuous one-line operation is possible and no special probing signals are required.