Research On Array Layout And Circuit Design Of 5.8GHz High Efficiency Rectenna Array

Microwave power transmission(MPT)is a kind of method of using microwave to carry out long-distance energy transmission,which is applicable to the situation where direct current energy is not easy to obtain,and has the application value in the fields of space,military,civil,medical and so on.The MPT system consists of a microwave transmitting antenna system and a receiving rectenna system.The receiving recenna system which is composed of receiving antenna and rectifier,often arranged in an array form.And it is one of the keys of the MPT system.However,there is still no perfect theoretical support for the design of the rectenna array.In view of this,this paper aims to realize the high efficiency of entire rectenna array,and the work is carried out in three aspects: research on the method of sub-array layout;design of high efficiency rectifier and design of direct current synthesis circuit.The specific research work is as follows:(1)Research on the method of sub-array layoutIn order to solve the problem of low efficiency and high complexity of the two existing array layout methods for receiving rectenna array,a subarray layout method is proposed.Firstly,based on the Friis equation,the subarray receiving power calculation model is established.Then based on this calculation model,the subarray layout optimization model which is aim to achieve the purpose of uniform reception power of subarrays is established.Secondly,the local search algorithm is used to solve the optimization model.Finally,the effectiveness of the subarray layout method is verified by comparing the simulation result of subarray layout method with the existing two layout methods.(2)Design of high efficiency rectifierAiming at high conversion efficiency,two kinds of rectifier with different input power are designed.Firstly,two kinds of rectifier are designed and simulated with the help of ADS by using diodes of HSMS2860 and HSMS2820.Then,the two rectifier are tested and verified based on the test method of efficiency and large signal reflection coefficient proposed in this paper.The simulation and test results show that the simulation rectification efficiency of the two rectifier circuits is 80% and 78.5%,the test rectification efficiency is 75% and 62%,and the reflection coefficient is lower than-20 dB.It is proved that the designed rectifiers have high conversion efficiency.(3)Research on Series-parallel method of DC SynthesisIn order to solve the problems of large loss and poor load capacity of the traditional DC synthesis methods,the dynamic series-parallel method is studied.Firstly,Based on the test data of designed rectifier,the equivalent circuit model of single rectifier is established.Secondly,based on the equivalent circuit model of single rectifier,the volt-ampere characteristic curve of series-parallel system of rectifier array is derived,and the correctness of the derivation relationship is verified by experiments.Thirdly,based on this relationship,in order to enhance the load capacity of rectifier array system,a dynamic series-parallel optimization model is established,and the genetic algorithm is used to solve the optimization model.Finally,a dynamic series-parallel circuit which is easy to realize is given.