Abstract: Considering the inter-carrier interference (ICI) when the variety of channel is comparatively large, a novel paraller interference cancellation(PIC) equalization method is proposed that can be applied to the time variant WLAN and WMAN systems. The time impulse response of the channel is estimated using the preamble sequence. By assuming the channel to be linearly variant, the pre-filter and ICI cancellation filter is used at the same time to cancel the ICI, the initial decision of the pre-filter can reduce the enhancement of the noise attaining better performance.