Analysis of the tap weight fluctuation in zero forcing automatic equalizer

Abstract

Long‐term instability is one of many serious problems in Zero‐Forcing (ZF) automatic equalizers for television signals. This paper analyses this problem by solving the tap weight covariance matrix. the result is that the tap weight fluctuation (variance) increases significantly as the input signal bandwidth becomes narrow and/or the number of taps increases. the leakage algorithm which is very effective in reducing the tap weight variance is examined also. In addition, the timing adjustment which is another problem in the ZF algorithm, is examined and it is proved that the leakage algorithm does not improve the instability caused by timing misadjustment.