Digital receiver evaluator measuring reception quality - subjects demodulator or comparator to perturbation and obtains pseudo-error rate at adder output

摘要

The evaluator measures the quality of reception of a regenerator's receiver in a digital communications link or of a digital receiver by using a corrective demodulator or comparator and an auxiliary demodulator or comparator functioning in a perturbation mode. A pseudo error is obtained at the output of a modulo 2 adder whose inputs are connected to the outputs of the demodulators or comparators. The level of perturbation to which the auxiliary demodulator or comparator is subjected is controlled such that a constant pseudo error rate is obtained at the output of the adder. The value of this level of perturbation determines the quality of reception.