An Adaptive Robust Fuzzy Detector for Narrowband Interference Cancellation in DS-CDMA Communications

Abstract

The significant performance degradation occurs when the direct-sequence code-division multiple access (DS-CDMA) communication systems presence the narrow-band interference (NBI). In this paper, we design a two-stage cancellation filter to deal with both NBI and multiple access interference (MAI). First, adaptive robust fuzzy cancellation filters, which adopt the method of fuzzy logic systems to modify the ratio of reduce the NBI to the MAI. Next, a set of MAI cancellation filters is developed to improve the signal to interference ratio (SIR) and handle the MAI effect. The simulation confirms that the proposed scheme performance is significantly improved and to avoid performance deterioration due to the unreliable initial detection if the NBI and the MAI is considered in our proposed design criterion.