2015/11/12 by Seyed Eman Mahmoodi, K. P. Subbalakshmi, Mahmoodi, S. Eman +5
Computer Science · Engineering · #Advanced MIMO Systems Optimization #Cognitive Radio Networks and Spectrum Sensing #Cooperative Communication and Network Coding #FOS: Computer and information sciences #Information Theory (cs.IT)
paper · pdf · doi:10.48550/arxiv.1511.04115
openalex publication_date 2015/11/12 · openalex created_date 2022/10/05 · openalex updated_date 2026/07/28
In this paper, we investigate the joint spectrum sensing and resource\nallocation problem to maximize throughput capacity of an OFDM-based cognitive\nradio link with a cognitive relay. By applying a cognitive relay that uses\ndecode and forward (D&F), we achieve more reliable communications, generating\nless interference (by needing less transmit power) and more diversity gain. In\norder to account for imperfections in spectrum sensing, the proposed schemes\njointly modify energy detector thresholds and allocates transmit powers to all\ncognitive radio (CR) subcarriers, while simultaneously assigning subcarrier\npairs for secondary users (SU) and the cognitive relay. This problem is cast as\na constrained optimization problem with constraints on (1) interference\nintroduced by the SU and the cognitive relay to the PUs; (2) miss-detection and\nfalse alarm probabilities and (3) subcarrier pairing for transmission on the SU\ntransmitter and the cognitive relay and (4) minimum Quality of Service (QoS)\nfor each CR subcarrier. We propose one optimal and two sub-optimal schemes all\nof which are compared to other schemes in the literature. Simulation results\nshow that the proposed schemes achieve significantly higher throughput than\nother schemes in the literature for different relay situations.\n