Resource Allocation for Heterogeneous Cognitive Radio Networks with Imperfect Spectrum Sensing
In this paper, the authors study the Resource Allocation (RA) in Orthogonal Frequency Division Multiplexing (OFDM)-based Cognitive Radio (CR) networks, under the consideration of many practical limitations such as imperfect spectrum sensing, limited transmission power, different traffic demands of secondary users, etc. The general RA optimization framework leads to a complex mixed integer programming task which is computationally intractable. They propose to address this hard task in two steps. For the first step, they perform sub-channel allocation to satisfy heterogeneous users' rate requirements roughly and remove the intractable integer constraints of the optimization problem. For the second step, they perform power distribution among the OFDM sub-channels.