Power minimization in multi-user OFDMA-based cognitive radio systems with guaranteed throughput provision

Cognitive Radio (CR) is an innovative technology, which will capable future wireless networks to utilize the spectrum more efficiently. Orthogonal Frequency Division Multiplexing (OFDM) because of its unique features, is one of the best candidates for implementing CR. Due to services that new generations of networks are presenting, a guaranteed throughput for these networks becomes so important. In this paper, a resource allocation algorithm for the downlink of a multi-user OFDM-based CR system is presented. The presented algorithm provides a guaranteed throughput for CR users, with minimum power consumption while keeping the interference to each primary user (PU) below a certain threshold. The performance of the proposed algorithm is compared with Sum Throughput Maximization Algorithm and Uniform Resource Allocation Algorithm.