Research On Frequency Scanning Antenna

With the rapid development of radar,communication,imaging and other technologies,electronic beam scanning antenna has been widely used in various fields.Frequency scanning antenna,which changes the beam direction by changing the operating frequency,has the advantages of low cost and simple realization.Based on stripline and substrate integrated waveguide(SIW)as slow wave lines,this paper designed two frequency scanning antennas.The main work is as follows:First,several key issues in frequency scanning antenna design are studied.Firstly,the correspondence between the working frequency band and the scanning angle in the frequency scanning antenna is analyzed and the conclusion is drawn.Then,the relationship between the aperture distribution of the antenna array and the coupling coefficient of each element is analyzed,and the coupling coefficient is calculated by MATLAB program.Finally,different types of transmission lines are compared,and the loss is analyzed and simulated.Second,this paper designed two frequency scanning antennas,using stripline and substrate integrated waveguide as a slow wave transmission line respectively.The two antennas adopt different radiating elements and coupling structure,in which the stripline frequency scanning antenna adopts Vivaldi antenna unit and parallel coupling line directional coupler;the SIW frequency scanning antenna adopts microstrip patch radiating element and slot coupling structure.Simulation and test results show that when the stripline frequency scanning antenna operates between 9.5GHz and 10.5GHz,the corresponding scanning angle is up to 50 degrees.And when the SIW frequency scanning antenna operates between 10 GHz and 10.5GHz,the corresponding scanning angle is up to 36 degrees,which proves the feasibility of the design in practical application.