Wireless Energy-carrying Relay Based On Generalized Carrier Index Differential Chaos Shift Keying

With the rapid development of Fifth Generation(5G)mobile communication and Internet of Things(Io T),the number of sensor nodes in wireless sensor networks(WSNs)has increased dramatically,leading to more severe spectrum scarcity and energy shortages.Therefore,applying energy-efficient and green communication technologies to WSNs is essential to solve these problems.Currently,Two-way Relay(TWR)technology has become a research hotspot in the field of WSNs.However,the limited battery life of relay nodes renders the two-way relay system unable to function properly.Thus,researching low-cost and sustainably powered TWR technology can not only prolong the lifespan and coverage range of wireless sensing nodes but also avoid network interruptions caused by signal attenuation and obstruction,thereby improving network transmission reliability.Digital chaos modulation technology has the advantages of low complexity and low power consumption and can effectively solve the energy-limited problem of WSNs through simultaneous wireless information and power transfer(SWIPT)technology.In addition,network coding(NC)technology also plays an important role in improving the throughput performance and spectrum utilization of TWR systems.While SWIPT technology has been researched and applied in TWR networks,there are still limited studies on applying SWIPT-based digital chaos communication technology to TWR systems.Therefore,this paper combines TWR with SWIPT and digital chaos modulation technology and conducts in-depth research on it.The main contributions are summarized as follows:(1)To solve the energy consumption issue of sensing nodes,an improved digital chaos communication system with lower power consumption and hardware complexity was chosen,and SWIPT technology was used for simultaneous signal and energy transmission.This paper presents a GCI-DCSK SWIPT system that integrates generalized carrier index differential chaos shift keying(GCI-DCSK)modulation technology with SWIPT.The bit error rate(BER)performance,energy sustainability,energy efficiency(EE)and spectrum efficiency(SE)of the system are analyzed.Additionally,optimization methods for factors that affect the system’s BER and energy sustainability are introduced,and the GCI-DCSK SWIPT is compared with CIDCSK1/2 SWIPT and GCI-DCSK systems in terms of performance.(2)Due to the limited transmission range of WSNs,when the distance between nodes is too far,it aggravates the path loss and increases the probability of signal distortion.Therefore,a GCI-DCSKbased wireless energy-carrying three-time slot bidirectional single relay system is investigated,where the relay nodes use direct network coding technique and decode-and-forward(DF)technique,and all the collected energy is used to process and forward the signals.The BER and outage probability of the system are analyzed,and the correctness and feasibility of the scheme are verified by simulation analysis.The results show that the proposed GCI-DCSK SWIPT system has more flexibility in terms of EE and SE,and has relatively good BER performance based on achieving energy self-sustainability.The GCIDCSK-based wireless energy-carrying three-time slot two-way single relay system not only expand the communication coverage,but also realize green energy transmission.