| The antenna is one of the important components in modern wireless communication systems.In practical applications,it is rapidly becoming more compact,broadband and highly integrated.The substrate integrated waveguide(SIW)antenna is a novel antenna with small size,light weight,low circuit cost,high Q value,low loss,and easy integration with planar circuits.Since the substrate integrated waveguide structure is similar to the metal waveguide structure,it also has the advantages of high performance,high power,high thermal stability and structural stability similar to those of the conventional metal waveguide antenna.The millimeter wave frequency is higher and the information storage capacity is larger,but because of its large propagation loss in the air,it is particularly important to study a high gain millimeter wave antenna.The thesis focuses on antenna arrays with high gain,wide bandwidth,stable pattern,high efficiency and easy integration.First,a common high-gain back-cavity antenna is proposed.This conventional back-cavity antenna has the advantages of high gain,high efficiency and stable pattern,but it is rarely applied to the antenna array due to its large size.The thesis then proposes a substrateintegrated waveguide back-cavity antenna that not only has the advantages of a backcavity antenna,but also has the advantages of small size and ease of integration.In this thesis,the substrate integrated waveguide back cavity microstrip patch antenna is designed and simulated by HFSS.The antenna operating frequency is 55.9GHz-58.4GHz,and the antenna resonant frequency is 56.6GHz,S11=-33.92 dB,and the gain is 8.0273 dBi.And the simulation obtained the antenna has higher efficiency and can reach more than 90.5%.Prepare for the design of the antenna array.The thesis designs an1?4 antenna array based on the substrate integrated waveguide back cavity microstrip patch antenna.The array uses a linear array and a one-point fourpower splitter feed.The gradual transition is used to reduce the parasitic capacitance caused by the ground of the coplanar waveguide and the ground of the microstrip not on the same plane,and the antenna coplanar waveguide feed is successfully converted into a microstrip feed.The paper adopts the way of merging the back cavity walls of adjacent array elements to reduce the size of the antenna array and realize the miniaturization of the antenna.At the same time,the performance of the antenna array is not reduced compared with the antenna array before the back cavity is combined.The maximum gain of the antenna array obtained by HFSS simulation is 19.7 dB,which effectively increases the gain of the antenna relative to a single independent antenna.Since the millimeter wave test system mostly supports the rectangular waveguide interface,the paper uses the fin line transition method to convert the microstrip into a waveguide,which is convenient for antenna testing. |
