Neuro-fuzzy controller for reverse link power control of DS-CDMA system over multi-path fading

This paper presents the Direct Sequence-Code Division Multiple Access (DS-CDMA) model and the algorithm to control the reverse link closed loop power of DS-CDMA cellular system by using the Neuro-Fuzzy Controller (NFC). The controller´s parameters of this method are selected and adjusted by Genetic Algorithms (GAs). The controller´s inputs are the error between the signal strength of each mobile station and signal strength target (P*) at base station, and the difference of this error. The controller´s output is the increasing or decreasing power. The NFC was then tested to control DS-CDMA model which designed synchronous transmission. In the test, M sequence code used in spread spectrum was utilized under multi-path fading. The experimental results by comparing the operation characteristic of the designed and implement NFC with fuzzy controller (FC) and IS-95 controller show that the NFC gives the power level closed to the target and a lower outage probability.