Method for determining the quantisation distortions of transmission devices, particularly for PCM

摘要

In this method, a quasi-stochastic noise signal is used at the transmitting end and the noise signal and the signal components produced by distortion are evaluated in two measuring branches at the receiving end. To achieve a short measuring time with high accuracy of the measurement signal, the quantisation distortion is determined in three measuring phases by means of a quotient analog/digital converter QAD, after the signal components Az(t), An(t) have been integrated together in the two measuring branches, the quantisation distortion is determined from the reverse-integration time by reverse integration of the output variable Ana(t) of the second integrator IN as reference variable. The invention can be mainly applied in the testing of telephone lines. <IMAGE>