Abstract
Signal processing is the critical equipment and the guarantee of technology to media gateway, so it is very important to evaluate the signal processing effect of media gateway. In this paper the Correlation Criterion which is based correlation operator on theory and uses correlation coefficient as the index of evaluation is put forward. In this method, the select of standard test signal is the key. The paper introduces the dependence and reason of choosing standard test signal. The cross correlation criterion is a normalized, quantitative, time domain evaluation method.