Research On Leaky Wave Antenna And Array Antenna Integrated Substrate Gap Waveguide Technology

The development of 5G communication technology has greatly promoted the research of millimeter wave antennas,and at the same time,higher requirements have been put on millimeter wave antennas.Due to its own characteristics,leaky wave antennas have been rapidly studied by experts and scholars since they were proposed,and have been widely used in microwave and above frequency bands.With the emergence of the planar leaky wave antenna,it has a new look in the millimeter wave band,low cost,simple structure and easy processing.In recent years,Integrated Substrate Gap Waveguide(ISGW)is a novel waveguide structure proposed that can work in high frequency bands.The waveguide has high efficiency,low loss and wide bandwidth characteristics.At present,microwave devices based on this waveguide technology,such as filters,circularly polarized antennas,couplers,etc.,have been processed and have good performance.This new type of waveguide technology can effectively solve the instability of the gap waveguide and the mode conversion problem of SIW,and meet the needs of the current5G communication technology.Based on this,this paper studies the leaky wave antenna and its array antenna that can work in the 5G band around this waveguide technology.In this paper,the specific research work is as follows:1.Three types of leaky wave antennas based on integrated substrate gap waveguide are proposed.The three types of ISGW-LWAs are:Cross-shaped slots ISGW-LWA,Rosette-shaped slots ISGW-LWA and Gear-shaped slots ISGW-LWA.And using the HFSS soft(High Frequency Structure Simulator)to model and simulate the three types of ISGW-LWAs.The performance of the three ISGW-LWAs was evaluated through the results of the S-parameters,antenna gain,and radiation efficiency obtained from the simulation.2.Through evaluation and comparison,the ISGW-LWA with the Gear-shaped slots was finally selected as the best of the three ISGW-LWAs.The ISGW-LWA can work at25.5GHz-28.8GHz,the relative bandwidth is 12.1%,and the S₁₁ parameters are less than-10dB,and the S₂₁ parameters are less than-23.5dB,which shows that this ISGW-LWA not only matches well but also most of the electromagnetic energy can radiate out of space.At the same time,the radiation efficiency of ISGW-LWA operating in this frequency range is 87.3%to 99%,and the antenna gain range is 10.35dB-13.9dB.3.A T-shaped power divider based on integrated substrate gap waveguide technology is proposed.The ISGW T-shaped power divider operates in the frequency range of 24.5GHz to 29.5 GHz.S₁₁ is lower than-14.5 dB over the entire frequency band,and the relative bandwidth is approximately 18.5%.And the insertion losses(i.e.S₂₁ and S₃₁)are relatively small,both around 3.35dB,which meets design requirements and can be applied to 5G communication systems.4.A new type of leaky wave antenna array based on ISGW T-shaped power divider is proposed:The Normal ISGW-LWA array(NISGW-LWA Array).NISGW-LWA array can work in the frequency band 24.7GHz-28.8GHz(relative bandwidth is about 15.3%);the radiation efficiency of the array antenna is between 89%-99%,and the gain range is11.4dB to 17dB.Compared with the single ISGW-LWA,the gain of the NISGW-LWA array has increased from 14dB to 17dB for the single ISGW-LWA,which is an increase of about 3.1dB.The working frequency band of a single antenna is 25.5GHz to 28.8GHz.The operating bandwidth is between 24.7GHz and 28.8GHz,and the bandwidth is increased by 3.1%.Finally,the NISGW-LWA array was fabricated.5.Based on the NISGW-LWA array,another form of the ISGW-LWA array is proposed,i.e.the Bent Terminal ISGW-LWA array(BTISGW-LWA Array).Compared to the NISGW-LWA array,the other end of the BTISGW-LWA array is not an ISGW T-shaped power divider as a terminal load,but a bend microstrip line as a terminal load to absorb the remaining power at the end of the BTISGW-LWA array;The performance of the BTISGW-LWA array is not much different from that of the NISGW-LWA array,but the size of the BTISGW-LWA array is smaller and the cost is lower.