Quality monitoring system for digital signals includes discrimination of signal against levels, and use of average discriminated value

摘要

The system uses differentiation and probability density to determine signal quality. The procedure for monitoring the quality of a digital signal includes digitizing a discrimination level, and then discriminating a digital input signal into n levels (n being an integer greater than 2) by comparison of this value with the discrimination level. An average value of the discriminated signal is then detected, and a quality parameter is calculated on the basis of the average value. The quality factor may be determined by consideration of a probability density function along the length of the amplitude axis of the signal, formed by differentiation of the average value of the signal w.r.t the discrimination levels.