Co-channel interference mitigation in the time-scale domain: the CIMTS algorithm

In many communication systems, the problem of co-channel interference is encountered when along with the signal of interest (SOI), and one or more interfering signals are present in a common receiver. The SOI and the interference are correlated, possess similar characteristics and power, and share the same region of support both in the time and frequency domains. In this paper, we present co-channel interference mitigation in the time-scale domain (CIMTS) algorithm (for MPSK signals) which estimates the SOI and the interfering signal from their superposition in the presence of additive noise. This method is inspired by the reconstruction of interference from the null space of the SOI in the time-scale domain. Once the null space of the SOI is determined, the interfering signal is reconstructed via a set of linear operations. Therefore, the SOI is estimated by a simple subtraction of the estimated interference from the observations.