Research On Differential Millimeter Wave Probe Antenna

The millimeter-wave anechoic chamber is an important wireless equipment test system,and its test accuracy and test quiet zone size are its main performance indicators.The probe antenna as a signal receiving and sending component in the test system has an important influence on the performance of the test system.The traditional lowfrequency probe antenna takes the horn antenna as the main form.In a millimeter-wave small dark room,the probe antenna in the form of a horn antenna is difficult to meet the requirements of wide-angle co-polarization,small size,and low profile.Therefore,the research and design of the differential millimeter wave probe antenna are carried out in this paper.The main content of the paper is as follows:1.Designed a differential millimeter-wave magnetoelectric dipole probe antenna based on a substrate integrated waveguide.For the problem that the antenna profile of the millimeter wave probe is too high,which results in a small spatial range of the test dead zone and the co-polarization performance is difficult to meet high-precision testing,the radiation of the differential feed circuit with a microstrip to substrate integrated waveguide to the magnetoelectric dipole The unit performs differential coupling feeding,achieving co-polarization of less than-20 d B in the range of ±30°,symmetrical radiation pattern,3d B beam width of 40° and maximum gain of 10.56 d Bi,ensuring high test accuracy.The working bandwidth of the antenna(S11<-10 d B)is 31.6GHz-34GHz;the antenna size is 36mm×16mm×1.6mm,with a low profile of 0.18?(? is the free space wavelength corresponding to 33GHz),providing a large test dead zone range.In addition,a micro-strip-to-substrate integrated waveguide differential feed structure was designed for physical testing of the antenna.2.Designed a differential millimeter wave array patch probe antenna based on the back cavity structure.For the non-integrated design of millimeter wave probe antenna differential feed and radiating unit and the influence of the overall size of the antenna on the test dead zone range and co-polarization performance,the antenna cavity is used to expand the working bandwidth of the antenna and improve the antenna performance;one-fourth difference The feeding network realizes differential coupling feeding to the 2×2 patch array,achieving co-polarization of less than-23 d B within ±40°,symmetrical radiation pattern,3d B beam width of 30° and maximum gain of 12.33 d Bi,To ensure a higher test accuracy.The working bandwidth of the antenna(S11<-10 d B)is 26.5GHz-40GHz;the antenna uses a three-layer plate structure to highly integrate the back cavity,the feeding network and the radiating unit,the antenna size is 19.5mm × 19.5mm × 6mm,with 0.67?(? For 33 GHz corresponding to the free space wavelength),the low profile provides a large range of test dead zone.