Joint Cross-Layer Scheduling and Spectrum Sensing for OFDMA Cognitive Radio Systems

In most of the existing works on cognitive radio (CR) systems, the spectrum sensing and the cross-layer scheduling are designed separately, where the cross-layer scheduling is performed based on the hard sensing information (HSI) generated from the sensing modular. In this paper, we shall propose a joint cross-layer and sensing design and study its performance advantages over the aforementioned traditional decoupled approaches. We shall also propose a joint design framework to optimize a system utility by adapting the power allocation and the subcarrier assignment across the secondary users (under a average interference constraint to the primary users) based on both the channel state information (CSI) and the raw sensing information (RSI). Simulation results reveals its substantial performance gain over the conventional CR systems.