Research On Energy Efficiency Optimization Mechanism Of Multi-hop D2D Communications Based On Network Coding

With The rapid development and application of 5G,the explosive growth of mobile terminal devices and data services has become a major problem faced by mobile communications.D2D(device-to-device)communication has the advantages of improving spectrum utilization,expanding network coverage and improving system throughput,so it has become an important research topic in the academic circle.Network coding technology can effectively improve the network throughput.Therefore,this thesis studies multi-hop D2 D communication based on network coding.Although some achievements have been made in the research of multi-hop D2 D communication based on network coding,there are still some problems and challenges,which are shown in the following aspects: 1)Most of the researches only focus on the specific two-hop D2 D communication scene,and do not extend the system scene to the general situation;2)some working assumptions are that the transmission power of D2 D terminal equipment is the same;3)in most studies on energy efficiency,the codec energy loss of network coding is not considered.To this end,this thesis proposes the topic of "research on energy efficiency optimization mechanism of multi-hop D2 D communication based on network coding".The main work is as follows:(1)Based on the two-way n-hop D2 D communication model,two coding schemes based on analog network coding are designed,and the general closed expressions of endto-end average bit error rate and system throughput in the two schemes are derived.The results show that the two schemes can improve the average bit error rate and throughput of the system,so as to improve the energy efficiency of the system.(2)Based on the multi-hop D2 D communication model in cellular network,an iterative power distribution strategy is proposed.In this strategy,considering the influence of co-frequency interference and network coding and decoding energy consumption on the energy efficiency optimization of multi-hop D2 D communication,the two-layer optimization method is adopted for the energy efficiency objective function.The simulation results show that the proposed power distribution mechanism can improve the energy efficiency of the system to some extent.In summary,this thesis conducts an in-depth study on the energy efficiency optimization direction of multi-hop D2 D communication based on network coding,proposes a network coding scheme for n-hop D2 D communication,and designs a power allocation strategy for multi-hop D2 D communication under cellular network,which provides a theoretical basis for promoting the development of energy efficiency optimization technology for multi-hop D2 D communication.