Joint spectrum sensing and resource allocation for multi-band cognitive radio systems with heterogeneous services

In this paper, we study joint spectrum sensing and resource allocation for heterogeneous services in multi-band cognitive radio systems. Two types of services are considered: delay-sensitive (DS) services and delay-tolerant (DT) services. Considering the influence of the probabilities of miss detection and false alarm, the detection threshold, power and sub-channel allocation are jointly optimized to maximize the total data rate of DT services while satisfying the delay requirement of DS services. For the protection of primary transmission, a new criterion referred to as rate loss constraint is introduced. With the queue theory, the delay requirements of DS services are transformed into constant rate requirements. The optimization problem is formulated as a three-variable non-convex problem under constraints. Moreover, by dividing the optimization problem into two stages, an iterative dual decomposition method is proposed to solve it. The effectiveness of our proposed algorithm is evaluated by extensive simulations and compared with existing algorithms.