A new signal quality degradation monitor for digital transmission channels

An innovative approach to the automatic monitoring of signal quality on digital transmission channels such as communication links is presented. A communication channel is said to be experiencing some form of stress when the channel (and hence the signal) is distorted from nominal conditions. The stress may be the result of a variety of sources such as transmitter and receiver equipment errors, ionospheric effects, tropospheric effects, and jamming. A new monitor, the DEGRAD (Digital Eye Gridded Receiver with Arbitrary Degradation) monitor, is developed that is better able to detect and identify channel degradations before a significant change in signal quality is noticed by the end user. >