An identification technique for the co-frequency mixed communication signals based on cumulants

Abstract

Identification of the co-frequency interference is a common problem in wireless digital communication systems. The high-order statistics (HOS) feature based on cumulants is a widely adopted solution. However, prior knowledge of the timings and the symbol period is required to extract the cumulants, which is quite difficult in a blind environment. In order to solve this problem, this paper proposed a more general calculation for the cumulants based on the over-sampled data with consideration of the inter-symbol interference (ISI). The generalized theoretical value of the cumulants is deduced in this paper. Besides, the HOS feature based on the generalized cumulants for identification is found to be robust with different roll-off factor and sampling number per symbol. Computer simulations are performed to prove the validity of the proposed method.