Design Of Ultra-wideband Tightly Coupled Array Antenna

Tightly coupled array antennas are widely used in engineering for their advantages of ultrawideband and high gain.Attributing to their miniaturized size and high compatibility with radar and warcraft systems,tightly coupled array antennas draw board attention in the field of electronic conutermeasures.In view of the above strengths exhibited by tightly coupled array antennas,we in this paper throughly investigate the following properties of the tightly coupled array antennas and how they can applied in the field of electronic contermeasures:1.Surrounding the application background and design objectives of this paper,the progress and research status of electronic countermeasures technology,ultra-wideband array antennas and tightly coupled array antennas at home and abroad are systematically investigated.The theoretical methods of tightly coupled array antennas are analyzed and researched,their radiation principles and analysis methods are introduced,the design idea of tightly coupled array antennas to broaden the antenna bandwidth is elaborated.on the basis of the above research,the radiation principles and design criteria of the proposed On the basis of the above research,the radiation principle and design criterion of the array antenna are demonstrated,and the theoretical foundation is laid for the subsequent chapters.2.Vivaldi antenna element applied to 1～5 GHz was designed and manufactured.The feed structure in the form of microstrip line-slotted line balun converter is designed.The current distribution when the element radiates is analyzed,and the antenna performance of the antenna element in the low frequency band is improved by loading the fence structure in the Vivaldi radiation patch.The physical processing and testing work of the Vivaldi antenna element is carried out on the basis of the simulation verification.the test results show that the fence structure can effectively improve the low-frequency characteristics of the antenna,which verifies the validity and achievability of the simulation work.3.A tightly coupled array antenna operating at 1～5 GHz is studied.The Vivaldi antenna is used as the basic element,which is formed into a one-dimensional infinite array along the E and H planes.Respectively,the truncation effect in the tightly coupled array is analyzed based on the mutual coupling effect between the array elements.Several methods to compensate for the truncation effect are summarized,and one of the methods is verified by simulation experiments.Based on the above studies,the simulation analysis of 8×8 finite large array is carried out.4.An improved tightly coupled array antenna operating at 1～5 GHz is investigated.By slicing the radiating body of the Vivaldi antenna,the high cross-polarization phenomenon under the non-principal plane(D-plane)beam scan in the array is effectively improved.The radiation efficiency of the array antenna is further improved.The improvement made in this paper retains the structure of Vivaldi antenna to the greatest extent,so it effects a little on the broadband characteristics of Vivaldi array antenna itself,which makes the array antenna achieve good broadband wide-angle scanning characteristics,and is more widely used in electronic countermeasures technology and applicable to most electronic defense and attack systems.