Design And Implementation Of Sum And Difference DF Antenna Array With Ratio Amplitude

In recent years,with the continuous development of radio technologies and the constant renewal of various radio services,urbanization in urban areas has been increasingly perfected,and the range of radio direction finding has been severely limited.Therefore,it is necessary to use simpler direction-finding equipment.It is found that the current individual direction-finding equipment is not only bulky and heavy,which makes the radio direction finding equipment gradually develop towards the direction of “reducing system complexity,combining software and hardware,and reducing system cost”,aiming at the above situation.In this article,the design of sum and differential of amplitude ratio direction-finding antenna array has the advantages of "light weight,simple structure and light weight,and easy to carry".Firstly,based on the principle of single pulse radar direction finding,combined with the actual engineering project requirements,a simple structure and a differential type of amplitude measuring direction antenna array are designed.Taking into account the difficulty of processing and production costs,the oscillator of a conventional stick-like log-periodic antenna is changed into a patch type in this article.Combined with technical indicators,the high-frequency electromagnetic simulation software HFSS is used to simulate and model the patch-type logarithmic antenna element.And the designed antenna unit is processed in kind,and the vector network analyzer is used to test the return loss.Then,to design the feed network.The feed network is an important part of most radio direction-finding systems,which is to generate the signals needed for antenna array direction finding.The function of the sum and difference feed network designed in this article is to perform the sum and difference processing of the two signals with the same frequency and phase received by the two antennas at the same time and obtain the sum signal and the difference signal respectively.Then ADS(Advanced Design System)software is used to design 0° power divider,0° combiner and 180° combiner,and verify the feasibility of the design.And the sum and difference feed network is consisted of the dividers and the combiners in-kind for actual testing.Finally,the antenna elements are arrayed,and the HFSS simulation software is also used to design the DF antenna array model.The influence of the binary element spacing on the pattern of the sum signal and the difference signal is analyzed.The final spacing of the array elements is 200 mm.The simulations were conducted simultaneously with the design of DF antenna arrays with different polarizations.According to the designed antenna array model,the physical array of antennas is performed,and the actual test of indoor and outdoor is performed.The Sum and Difference DF Antenna Array with Ratio Amplitude is designed in this article,which is mainly used in knapsack direction-finding systems.It not only has low processing cost,but also has a simple structure and is easy to carry.It can be operated by one person,or it can be coordinated by multiple people or with a mobile direction-finding vehicle.Used in conjunction with the remote mountain areas where the direction-finding vehicles cannot reach,it is more suitable and more practical.