A time-varying filter is proposed which improves by 5 dB upon traditional FRESH and Wiener filters when rejecting a pulsed radar signal. The filter is a Time-Varying FRESH (TV-FRESH) filter, which applies different sets of filter weights in a periodic manner, with the same periodicities of the received signal. Matching the periodicities of the filter to that of the signal improves the rejection of interference, producing a better estimate of the desired signal. The simulated results show mitigating the interference from a radar signal to an Orthogonal Frequency Division Multiplexing (OFDM) signal.