A relay selection method for swipt cooperative communication system based on firefly algorithm

Abstract

The invention discloses an SWIPT cooperative communication system relay selection method based on a firefly algorithm. With the purpose of maximizing channel capacity of a destination node, energy harvesting relay nodes are selected; the optimum number of relay nodes are reasonably selected by taking single carrier sending power minimum requirement factor into consideration; and moreover, the carrier number is allocated fully by taking spectrum utilization efficiency into consideration, so a spectrum utilization rate is maximized. According to the method, the firefly algorithm is applied to arelay selection problem in an SWIPT system. Through utilization of the algorithm, the reasonable number of relays are selected for transmission, so the relatively high optimization precision and a convergence rate are obtained. A standard firefly algorithm applies to a continuous variable space. According to the method, the algorithm is diffused according to a practical problem; distance calculation and a moving mode are changed; the distance among fireflies is measured through adoption of hamming distance; the algorithm is applicable to solution of a diffusion problem in a relay selection scene; locations of the fireflies are randomly moved; the diversity of firefly groups is increased; and the algorithm is prevented from entering local optimization solution.

Description

technical field [0001] The invention relates to the technical field of mobile communication, in particular to a firefly algorithm-based relay selection method for a SWIPT collaborative communication system. Background technique [0002] Multiple-Input Multiple-Output (MIMO) technology provides an effective solution to improve communication system performance, improve cell edge user throughput and transmission reliability. Cooperative communication technology makes full use of the relay technology and the omnidirectional propagation characteristics of radio waves, so that the nodes in the wireless network cooperate to form a virtual antenna array to obtain the space diversity gain that can be obtained by traditional MIMO technology. [0003] The traditional collaborative network has the disadvantages of limited battery capacity of relay nodes and inconvenient battery replacement, while the emerging wireless portable communication technology (SWIPT) can realize efficient and r...

AI Technical Summary

Problems solved by technology

[0004] At present, many studies have proposed various methods for relay selection in wireless cooperative communication systems, but most relay selection problems focus on considering the selection of a single relay node for cooperation

The publication number is CN104507144A, and the publication date is April 8, 2015. The invention patent "Wireless energy-carrying relay network joint relay selection and resource allocation method" considers relay selection strategy, channel allocation, source node, and relay node The joint optimization of power and relay node energy collection strategy maximizes network energy efficiency while ensuring user quality of service (QoS) requirements. However, this invention only considers the selection of a single subcarrier and a single relay node for cooperation, and does not consider Multiple relays bring improved system performance and utilization efficiency of the system frequency band, while the general convex optimization method is slow to achieve

Images