Pulse Shape Design for Efficient Rejection of Unknown In-Band Interference Using Cyclic Wiener Filtering

Abstract

We study cyclic Wiener (CW) filtering based interference rejection to deal with unknown jamming interference. A desired wideband signal is assumed to spectrally overlap with an unknown narrowband interference. At the receiver, the CW filter exploits the spectral redundancy associated with pulse shaping the desired signal for rejecting the interference and recovering the desired signal. Its performance, however, largely depends on the carrier frequency offset between the desired and interfering signals and the amount of excess bandwidth associated with pulse shaping the desired signal. To alleviate these problems, we propose new pulses that we name as time-domain shrunk raised cosine pulses. Proposed pulses satisfy the Nyquist criterion and, compared to conventional raised cosine pulses, largely improve the ability of CW filtering at rejecting in-band interference, even for a less amount of excess bandwidth. Besides, the almostflat shape of their frequency response is shown to entail a good performance for CW filtering irrespective of the carrier frequency offset between the desired and interfering signals.