Power Allocation Scheme and Performance Analysis for Multiuser Underlay Full-Duplex Cognitive Radio Networks With Energy Harvesting (original) (raw)
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This paper studies the achievable total throughput of an energy harvesting cooperative cognitive radio (CR) network. A CR transmitter cooperates with a primary user (PU) transmission if PU is found to be present in the given channel while it transmits its own data in the absence of PU. The CR transmitter is an energy harvesting node which harvests simultaneously from non-RF signal as well as RF signal of PU. The CR transmitter uses the harvested energy on shared basis for cooperation and transmission. The same study is also extended for cooperation of multiple CRs in multiple PU band scenario. In cooperation in muti-band scenario, all CRs sense all PU channels and sensing informations are fused at fusion centre to know about the status of PU. Performance is investigated in terms of total network throughput for several parameters such as sensing time, energy splitting parameter, and energy allocation ratio etc. Novel analytical expressions for total useful throughput and optimal energy allocation ratio parameter under the considered network scenario are developed. Useful throughput and optimal energy allocation ratio parameter are also estimated for a target secondary network (CR network) throughput under a quality of service constraint of PU such as collision probability. It is observed that the value of optimal energy allocation parameter gets reduced if the number of CRs in cooperation increases or the number of PU channels increases.
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This paper analyzes cooperative spectrum sensing with energy harvesting using power splitting mode of operation simultaneously. Secondary users (SU) will harvests RF energy from primary user (PU) throughout the durations of sensing and transmission. The main aim of this paper is to analyze the residual energy of SU with power splitting ratio, number of samples, number of SUs and probability of detection. Mathematical expressions of energy consumption, harvested energy and residual energy are developed. The simulation results of residual energy with different parameters are verified and have proved that residual energy of SUs is increased with increase in power splitting ratio, number of SUs, number of samples of SU for sensing and probability of detection
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