Design And Research Of Dielectric Embedded Special Yagi Antenna

With the development of wireless communication,the requirements for antennas are also changing,so many different types of antennas need to be designed to achieve the performance we want.In navigation and communication systems,higher requirements are placed on antennas,such as small size,conformability,and dual beams.The microstrip Yagi antenna not only has the advantages of two kinds of antennas,but also reduces the size of the antenna and improves the front-to-back ratio of the antenna.But their conformal effect is not good,and the dielectric embedded antenna can solve this problem well.Later,some scholars studied the microstrip Yagi antenna embedded in the dielectric with normal shape,which can solve the problems of directivity,integration,and especially conformal,but did not solve the dual beam characteristics.In this thesis,combined with microstrip antennas,Yagi antennas,and dielectric embedded antennas,the dielectric embedded special-shaped Yagi antennas have been studied to solve the problem of dual beam implementation.It not only has good application prospects in communications,but also has greater application value in electronic reconnaissance and air warning.The main work is as follows:In this thesis,the dielectric embedded special-shaped Yagi antenna is taken as the research object,the microstrip special-shaped Yagi antenna is buried in the dielectric,and a kind of dielectric embedded special-shaped Yagi antenna is studied.The electromagnetic simulation software HFSS is used to simulate the antenna performance.A set of simulation experimental data is obtained: the maximum gain of the antenna is 4.16 d B,the resonance frequency of the antenna is 15.7GHz,the antenna bandwidth is 2.52 GHz,the antenna standing wave ratio is 1.25.When the antenna reaches its maximum gain at the resonance frequency,the E-plane pattern corresponds to two beams: at ? = 15°,the lobe width is 17°,the gain is 4.1d B;at ? = 345°,the lobe width is 17°,the gain is 4.16 d B.Based on this research,the improvement of the antenna performance was explored.By adding a "fence"(parasitic vibrator),a simulation test was carried out on the modified dielectric buried Yagi antenna,and a set of data was obtained: the maximum gain of the antenna is 5.06 d B,the resonance frequency of the antenna is 15.58 GHz,the antenna bandwidth is 2.54 GHz,and the antenna standing wave ratio is 1.24.When the antenna reaches its maximum gain at the resonance frequency,the E-plane pattern corresponds to two beams: at ? = 14°,the lobe width is 15°,the gain is 4.92 d B;at ? = 346°,the lobe width is 16°,the gain is 5.06 d B.The simulation results show that after adding the "fence",the antenna gain is increased,the bandwidth is increased by 20 MHz,and the half-power beam width of the antenna on the E-plane is reduced,which shows that the "fence" effectively improves the antenna performance and plays a role.Then the improved antenna is made,and the antenna is tested to obtain the test result.The test results show that the working frequency of the antenna is 15.46 GHz,the maximum gain of the antenna is 3.92 d B,the frequency range of the antenna reflection coefficient less than-10 d B is 14.67 GHz ? 16.57 GHz,the absolute bandwidth is 1.9GHz,and the relative bandwidth is 12.3%,the antenna standing wave ratio is 1.28.When the antenna reaches its maximum gain at the resonance frequency,the E-plane pattern corresponds to two beams: at ?=15°,the lobe width is 11°,the gain is 3.81 d B;at ?=347°,the lobe width is 10°,the gain is 3.92 d B.