cooperative sensing with transmit diversity based on randomized stbc in cr networks
In this paper, a cognitive radio (CR) network composed of K secondary users who cooperatively sense a channel using the k -out-of- K fusion rule to determine the presence of the primary user is studied. The sensing-throughput tradeoff problem is investigated in a realistic environment where both the sensing channels and reporting channels are characterized by fading channels. It is observed that taking into consideration the probability of reporting error in the CR network increases the sensing time and reduces the maximum average throughput of the secondary users. To mitigate the effect of the probability of reporting error, a transmit diversity based cooperative spectrum sensing method using randomized space-time block coding (RSTBC) is proposed. Simulations results show that the spatial diversity gain induced by RSTBC significantly decreases the sensing time and improves the throughput of the secondary users.
cooperative sensing cognitive radio networks optimization sensing throughput tradeoff