Adaptive resource allocation in multi-user OFDM-based Cognitive Radio systems

Cognitive Radio (CR) is a promising concept for improving the utilization of scarce radio spectrum resource. OFDM is considered as a well-matched technology for CR systems. Resource allocation is a vital task in such systems. In this paper, we model the problem of subcarrier, bit and power allocation for multi-user OFDM-based CR systems with imperfect spectrum detection and mutual interference consideration. Based on this model, we propose three similar resource allocation schemes which aim at maximizing the throughput of CR system in a greedy approach. Numerical results show the effectiveness of our proposed schemes.