Research On Characteristics Of Substrate Integrated Waveguide And Single Pulse Antenna Design

Substrate Integrated Waveguide is an excellent planar waveguide structure.The SIW has high Q value and low loss,which makes it widely used in the manufacture of passive microwave components such as filters and power splitters.More importantly,its processing is simple.Low profile structure makes it easy to combine with active circuit and thus plays an important role in the miniaturization of microwave devices.The monopulse radar system can accurately locate the elevation,azimuth,and distance spatial information of a target by transmitting and receiving pulse signals,and is thus widely used in the field of flight navigation,missile tracking,etc.However,the traditional single-pulse antenna is often bulky,heavy and difficult to process,and costly.Therefore,it is considered to use a substrate integrated waveguide technology to improve the traditional single-pulse antenna design method.This article uses SIW design and simulate Ka-band and X-band single-pulse antennas with center frequencies of 34.5 GHz and 10 GHz,respectively.The dielectric plate material used was CLTE-XT high-frequency plate of Rogers Company with a dielectric constant of 2.94.The Ka-band monopulse antenna thickness is 0.76 mm and the overall size is 159.7mm×87mm×0.8mm.Simulation results show that the antenna gain is 20 dB,the elevation sidelobe levels are less than-29.6dB,and the azimuth sidelobe level is less than-20 dB,the elevation difference beam zero depth is-33.5dB,and the azimuth difference beam zero depth is-55.3dB.The X-band thickness is 2.29 mm.In order to increase the effective area of the X-band single-pulse antenna,the radiation surface of the X-band single-pulse antenna is in the form of a circular array,and the power division network,the sum-difference network,the phase adjustment structure,and the radiation are designed in the corresponding layers,and energy transmission is achieved through coupling holes between the layers.Finally,a six-layer single-pulse antenna structure is realized.The overall size is ?=144 mm in diameter and h=14.4 mm in thickness.The simulation results show that The antenna gain is 17.6dB,the elevation sidelobe levels is less than-22.6dB,the azimuth sidelobe level is less than-24 db,the elevation difference beam zero depth is-31.7dB,and the azimuth difference beam zero depth is-26.9dB.The specific work is as follows:1.This article studies the structural characteristics and propagation characteristics of SIW,and points out that it has similarity with the waveguide when working in the fundamental mode of the corresponding waveguide,we can get the equivalent relationship between SIW and waveguide.through the empirical formula and HFSS electromagnetic simulation.2.Analyze the array antenna theory and the standing wave slot array theory,calculate the SIW radiation gap length,width,center offset and other parameters through programming,and use the HFSS electromagnetic simulation software for simulation and optimization to complete the X-band back-to-back 10 slots,8 slots,6 slots and Ka-band back-to-back 12 slots one-dimensional standing wave slot array design and simulation.3.Use the SIW technology to implement a sum-difference network design because the low-side lobes of the elevation plane and the azimuth plane must be realized at the same time.Therefore,the power divider is required to achieve power distribution that conforms to the Taylor distribution,and 1 to 8 unequal power divider is realized using the SIW.The divider design,at the same time,adjusts the phase of each output port,so that the current distribution of the final elevation surface meets the phase requirement of the Taylor distribution,and finally completes the design and simulation of the whole single pulse antenna.At the same time,a Wilkinson power divider with high isolation and large power ratio dividers and the sum-difference networks in the form of microstrip have designed.This article has the following features: First,in order to increase the effective area of the radiating surface,the X-band consists of a 10-slots slot,8-slots,and 6-slots onedimensional standing wave slot array to form a circular array,effectively utilizing the area of the radiating surface..Secondly,the Stevenson formula of the standing wave slot array theory is improved in combination with a specific design situation,so that the results obtained by the formula are more agreement wiith the actual results.Third,using SIW to design a 1 to 8 unequal power divider,so that the output current of each output port of the power divider accords with the Taylor distribution,and then realize the low sidelobe radiation characteristics in the elevation plane.