This paper proposes a new fuzzy-based multi-rate STBC transmission method over dynamic fading channels in order to have an optimal channel usage and to control performance according to the instantaneous channel situations. The proposed method employs a fuzzy inference system (FIS) over estimated average delay and minimum value of cost function designed for Alamouti code in each block decision. We consider several membership functions (MBFs) and rules to cover all possible values of the parameters. Monte Carlo simulation is used to evaluate the system performance in mobile radio channel environments according to the COST207* channel model.
