The relationship between an adaptive quantizer and a variance estimator (Corresp.)

In this correspondence, it is shown that an adaptive quantizer with a one word memory can be viewed as one that estimates the variance of its input and normalizes the input by the square root of the estimate. It is shown that, even though the estimate is an exponential average, the effect of transmission errors does not die out. Finally, a method of combating the effect of such errors is described.