Research On Millimeter-wave Patch And Metasurface Antennas

In recent years,with the rapid development of modern wireless communication technology,the fifth generation mobile communication(5G)technology has attracted more and more attention.Since the channel capacity is closely related to the spectrum bandwidth,the millimeter-wave frequency band with extremely wide bandwidth has been favored by people as one of the application frequency bands of 5G communication.5G millimeter wave communication technology has obvious multi-frequency and multi-functional characteristics,so that the antenna system must be upgraded accordingly.Based on this research background,in this work,millimeter-wave patch antennas and metasurface antennas are selected as the research objects for detailed research.The main research work of this thesis includes:1.A millimeter-wave differential filtering dual-patch antenna based on coupled power divider feeding is proposed.Using the combination of cascade design method and fusion design method,a differential filtering dual patch antenna based on coupled power divider feeding with good filtering performance,obvious gain nulls and adjustable bandwidth is realized.It has a relative bandwidth of 8.92%in the passband,the peak gain in the working band reaches 6.92 dBi,and there are two gain nulls with gains lower than-15 dBi outside the band,and the cross-polarization performance is good.The physical prototype of the antenna was processed and measured.2.A millimeter-wave dual-band metasurface antenna designed based on the eigenmode analysis method is proposed.Using the method of eigenmode analysis,the prototype of the metasurface patch is structurally improved,and the performance improvement of bandwidths and gains is realized in two frequency bands of millimeter-wave.The 10 main characteristic modes of the metasurface structure are analyzed,and the performance of the metasurface radiation patch is controllable by adjusting its structure.Spurious modes in the passband are suppressed,allowing the main modes to exert better radiation performance.In the low-frequency and high-frequency passbands,it has relative bandwidths of 14.84%and 9.42%,and peak gains of 8.04 dBi and 7.79 dBi,respectively.3.A millimeter-wave dual-band metasurface antenna based on microstrip ridge gap waveguide feeding is proposed.The feeding structure of the metasurface antenna in the second part of the research work of this paper is improved.Through the design and analysis of the electromagnetic bandgap structural unit,the electromagnetic forbidden band matching the antenna passband is realized,and the feed part is introduced into the microstrip ridge gap waveguide structure to suppress electromagnetic leakage.In the low-frequency and high-frequency passbands,it has relative bandwidths of 10.96%and 11.3%,and peak gains of 9.85 dBi and 10.33 dBi,respectively.The physical prototype of the antenna was processed and measured.