Abstract: Cognitive radio (CR) is a new era of wireless communication system in which the use for efficient spectrum utilization of radio frequency (RF) band or RF channel for future wireless communication. Cooperative spectrum sensing is the very important key component of cognitive radio technology in which the sensing information from CR users combines at the Fusion center (common receiver) by soft combination or conventional hard combination techniques. Soft combination has excellent performance but, it requires a lot of overhead for feedback observation. In contrast, the conventional hard combination scheme requires only one bit of overhead, but it has worst performance because of loss of sensing information. Softened hard (quantized)decision fusion based cooperative spectrum sensing is optimum choice between overhead and detection performance. In this paper we mainly concentrate on the quantized (softened) cooperative spectrum sensing in environment of different fading channel like Rayleigh, Rice an and Nakagami. Centralized detection approaches are considered for the analysis of different data fusion rules of quantized cooperative sensing. The simulation result indicates the various types of analysis and comparison which can be very useful for analysis of fading in quantized cooperative spectrum sensing research and development.

Keywords: Cognitive radio, cooperative spectrum sensing, energy detection, fading channel.