Summary

(WiMAX) is an emerging broadband wireless technology that promises high-speed data services. Mobile WiMAX is a broadband wireless solution that enables convergence of mobile and fixed broadband networks through a common wide area broadband radio access technology and flexible network architecture. Mobile WiMAX is based on orthogonal frequency division multiplexing / orthogonal frequency division multiplexing Access (OFDM/OFDMA) technology [1, 2, 3]. It supports Adaptive Modulation and Coding in both downlink and uplink with variable packet size. This paper presents a new form of Adaptive Modulation (AM), which has the ability to enhance the data rate of Mobile WiMAX OFDMA system especially at low SNR values, this new form of AM will combine together with the simplest Peak to Average Power ratio (PAPR) reduction technique, which is the clipping to produce a novel algorithm called Modulation adaptation and Clipping algorithm (MC) has the ability to improve the performance of Mobile WiMAX system through reducing the PAPR, improving the SER performance, and increasing the data rate. Key words