Interference Mitigation via Doppler Filtering in Integrated Sensing and Communication Networks

Interference mitigation is one of the key challenges in wireless communication networks. Traditional approaches are based on the MAC layer scheduling or multiuser detection in the physical layer, in which signals are separated using either orthogonal channels or distinct waveforms. In this paper, motivated by the recently emerged integrated sensing and communications (ISAC), an interference mitigation scheme, based on the distinct Doppler shifts of legitimate signal and interference, is proposed, in which the physical features of legitimate transmitter are obtained from the capability of sensing in ISAC. An alternative motivation is the clutter mitigation in radar systems, which excludes clutters reflected from undesired objects in the Doppler domain. Different interference mitigation schemes are discussed for modulations in the time, frequency and delay-Doppler domains, respectively. Numerical simulations are carried out to demonstrate the validity of the proposed schemes.