Abstract
In this paper, we derive the detection probability of cooperative spectrum sensing using the energy detector with multiple branches and multihops in each branch. The primary signal passes through Li hops in the ith branch. Two cooperation protocols are considered. In the first one, the fusion center combines the signal of all branches, and it is known as all-participating relaying. It requires multiples channels for branch transmissions to avoid interferences. In the second one, only the branches with the highest SNR are activated. The results are valid for any number of hops and branches. We also consider situations where the direct link is available or not. We have studied the evolution of the detection probability with respect to the signal-to-noise ratio for a constant false alarm rate.