Cooperative Spectrum Sensing Over Weibull and Hoyt Fading Channels using Centralized and Distributed Schemes

Multipath fading, hidden terminal and shadowing are problems faced by users in non-cooperative type spectrum sensing techniques. A solution to this problem is Cooperative Spectrum Sensing (CSS) technique. CSS allows users to collaborate to perform spectrum sensing which may be managed by a common receiver. Further, it has two categories Distributed CSS (DCSS) and Centralized CSS (CCSS). In this paper these two schemes are compared with each other and different fusion rules are applied over them. Mathematical formulas for detection probability (Pd) of two fading channels namely Weibull and Hoyt are shown and further different fusion rules are applied on cluster-based CSS to explore the performance of centralized and distributed CSS. This concept has been earlier used for the conventional fading channels i.e. Rayleigh, Rician, Nakagami-m. In this paper results for cluster-based CSS are examined for comparatively lesser studied Weibull and Hoyt fading channels. It is noticed for different fusion rules, Weibull fading channel generates better performance as compared to Hoyt fading channel. This paper focuses on the implementation of four different fusion rules such as AND-AND, AND-OR, OR-AND along with centralized AND for these two fading channels. Results have shown that at SNR<5dB Weibull fading channel attains a higher probability of detection (Pd) than the Hoyt fading channel for all four fusion rules. It is noticed that the slope of the curve for Hoyt fading channel is steep as compared to Weibull fading channel and reaches to 0.9 Pd at SNR>5dB for OR-AND and AND-OR rule, while with these fusion rules, Weibull fading channel attains 0.9 Pd at SNR less than 0dB. OR-AND fusion rule gives the best result amongst all 4 fusion rules for both the channels.