Research On Millimeter Wave Antenna Based On Substrate Integrated Suspended Line

With the increasingly tight spectrum resources and the planning of internal frequency bands as 5G frequency bands,the design of antennas for the allocated mmwave for 5G has received huge importance in recent years.Due to the high frequency of millimeter wave,this frequency band has extremely wide spectrum,which injects fresh blood into the increasingly tight spectrum resources.Millimeter wave communication has high transmission effect and communication confidentiality.Because the millimeter wave wavelength is extremely short,the size of antenna in this frequency band is small,which is conducive to the miniaturization of antenna array and wireless system.However,compared with the microwave frequency band,the millimeter wave frequency band has higher atmospheric transmission loss.Therefore,the high-gain millimeter wave antenna and the low-loss transmission line connecting antenna and chip are the key to the research and development of the millimeter wave communication system.Substrate Integrated Suspended Line(SISL)inherits the advantages of low loss of traditional waveguide suspension lines and uses printed circuit technology to avoid the shortcomings of waveguide.This structure can meet the requirements of millimeter wave circuits for transmission lines.Many achievements have been made in the design and application of high-performance devices.Based on the excellent performance and structural advantages of the SISL structure in the millimeter wave frequency band,the millimeter wave antenna design is carried out to fully demonstrate the structural flexibility of the SISL and expand the idea of antenna design.This article explains the research background and research significance,introduces the characteristics and design theory of SISL,and learns the characteristic parameters and design theory of the antenna.Based on the above theoretical research,a linearly polarized antipodal linearly tapered slot antenna(ALTSA),a circularly polarized antenna system and a SISL-based circular polarized TSA are completed in the electromagnetic simulation software HFSS.The designed antennas are processed and tested.The test results show that the matching frequency band of the linearly polarized ALTSA antenna is 24.2-29.2 GHz.The ALTSA’s gain is higher than 8.18 dBi,and the highest gain of 9.16 dBi appears at the 26 GHz frequency point.The cross-pol gain in the direction of the main lobe is 15 dB lower than the co-pol gain.This antenna achieves high gain in the 26 GHz frequency band of 5G communication.The circularly polarized antenna system composed of Vivaldi antenna and H-plane horn antenna is impedance matching in the 25.5-27.7 GHz frequency band.In this frequency band the maximum gain is 6.13 dBi,and the axial ratio is lower than 3 dB.The cross-pol gain in the direction of the main lobe is 15 dB lower than the co-pol gain.This antenna achieves matching,stable-gain and circular polarized in the 26 GHz band.The SISL-based circularly polarized end-fire TSA impedance matching frequency band is 24.4-28.9 GHz.This antenna’s gain in this frequency band is 2.94-4.51 dBi,and the maximum gain of 6.15 dBi appears at the 26 GHz frequency point.Axial ratio is lower than 3 dB in the 25.5-28.3 GHz band.The cross-pol gain in the direction of the main lobe is 20 dB lower than the co-pol gain.This antenna achieves matching,stable-gain and circular polarized in the 26 GHz band.