Asymptotic performance of hierarchical fuzzy interference suppressors for CDMA

The paper presents a hierarchical fuzzy logic canceller that suppresses digital and/or analog interference from a CDMA signal. The optimum filter to remove them is the conditional mean estimator (CME) or the MAP detector of the interference. The CME and MAP, however, present a high computational burden which makes their feasibility difficult. To overcome this drawback, we propose a hierarchical fuzzy canceller that is beneficial in terms of computational load. Finally, asymptotic studies of the signal-to-interference-plus-noise ratio (SINR) improvement and the working region of the fuzzy canceller have been carried out.