ABSTRACT
This chapter analyses the functioning of the channel equalizer based on an Adaptive Network-based Fuzzy Inference System (ANFIS). It may be noted that the equalization of wireless mobile channels is a nonlinear problem, so a nonlinear solution is more appropriate. Fuzzy filters are nonlinear filters that incorporate linguistic information in the form of IF–THEN fuzzy rules. Fuzzy filters have been used for equalization due to their success in the related area of pattern classification. Fuzzy if–then rules or fuzzy conditional statements are expressions of the form IF A T HEN B, where A and B are labels of fuzzy sets, characterized by appropriate membership functions. Fuzzy modeling is applied to situations where the exact mathematical model is difficult to conceive and a measurement of values associated with the variables involved is quite tedious. The fuzzy if–then rules are generated by ANFIS based inverse system, which effectively acts as an adaptive equalizer at the receiver side.
