Fast and accurate testing of ISDN S/T interface devices using pseudo error rate techniques
B.W. Sprinkle · 2002
A procedure for extrapolating bit error rates (BERs) from a digital data receiver's ability to decode degraded data properly has been developed for ISDN (integrated services digital network) S/T interface loops. Three methods of signal degradation are described: noise addition, jitter addition, and intersymbol interference. It is shown that pseudo-error-rate (PER) testing reduces test time significantly and can be easily adapted to other forms of digital transmission. 1-s PER tests replacing 2.5-min BER testing are discussed. Results indicate a high degree of repeatability and confidence levels exceeding 90%. PER testing of ISDN S/T interface devices will reduce functional test time to a few seconds or less compared with several minutes for BER testing.>