本文着重分析PAL制彩色电视接收机爬行的原因及改进措施。理论上,边缘爬行(即大面积爬行)是由于梳状滤波器未调整好而引起的,群延时误差不符合要求是主要原因。实验验证指出,可以用改变带通形状的办法来调整群延迟时间的大小,从而改善彩条过渡处的分离比,减少边缘处的爬行现象。 This article focuses on the analysis of PAL color television receiver crawling reasons and improvements. In theory, the edge creeping (ie, large-area creeping) is due to the uncorrected comb filter, which is the main reason why the group delay error does not meet the requirements. Experimental verification indicates that the group delay time can be adjusted by changing the shape of the band-pass, so as to improve the separation ratio at the transition of the color bar and reduce the creeping phenomenon at the edge.