Performance Evaluation of OFDM Based Cognitive Radio System with Wiener Filter Channel Estimation Using Frequency Hopping GSM Channel Model at 900 MHz

The 900 MHz band (GSM band) is one of the highly occupied spectrum band. In this paper the access to such spectrum by the Cognitive Radio (CR) system using frequency hopping as a dynamic method of spectrum utilization is suggested. OFDM as an efficient modulation scheme is used, and the frame design according to the bluetooth TDD frame is considered. OFDM CR transmission over 900 MHz GSM band with frequency hopping in urban area and rural areas are simulated. The BER performances with 1-D Wiener Filter and 2times1-D channel estimation in the short packet frame (Bluetooth TDD frame) are evaluated. The results show how effective is frequency hopping CR OFDM transmission in 900 MHz GSM band.