Research Of High Power Millimeter Wave Directional Coupler

High power millimeter wave is widely used in plasma cyclotron resonance heating,directed energy weapons,high resolution radar,material handling,and other fields.Power monitoring is an important link of high power millimeter-wave application system,is the important content in the study of high power millimeter-wave transmission technology at home and abroad,directional coupler is a commonly used method of power measurement,but under the condition of high power millimeter-wave applications often face technical difficulties such as breakdown flint,mixed mode interferences and other technical problems.This paper mainly studied the high power millimeter wave directional coupler,explored the coupling theory,the coupling structure,power capacity,complex mode interference,polarization conducted in-depth exploration and monitoring in the direction of the beam respectively,concrete research results and the response of work is as follows:1.Revised the traditional theory of coupling holes.For the high power millimeter wave directional coupler coupling hole radius,thickness is bigger(relative wavelength),Lead to the results of numerical calculation and the results of actual engineering application comparatively large difference,put forward to add macroporous correction factor and thick hole correction factor method,improve the accuracy of the theory of coupling holes numerical results.2.The high power over mode circular waveguide TE01 choose mold directional coupler was studied based on the coupling theory of revised.Surrounding the impurity mode rejection problem of pore distribution of the three different structure are analyzed in detail.The phase superposition principle of the designed two sets of identical coupling aperture array,can effectively inhibit TE02 parasitic coupling mode.Main TE01 mode in 34 GHz ~ 36 GHz coupling for-46 dB ± 1 dB,Mixed mode TE02 coupling under 60 dB,mixed mode rejection degree greater than 15 dB than conventional coupling structure.3.The high corrugated waveguide HE11-TE10 porous directional coupler was studied based on the coupling theory of revised.Analyses the working principle of coupler,set up the simulation model,complete theory and simulation verification.Polarization monitoring methods are put forward on the basis of the millimeter wave directional coupler power monitoring structure,replaced the rectangular waveguide of coupler with square waveguide,by measuring the square waveguide TE10 and TE01 mode in the polarization direction of signal size to determine the polarization direction of HE11 mode.4.The application of millimeter wave directional coupler in the direction of the beam is studied.Through four groups of coupling hole array and two magic T to measure beam incident direction deviation and the deviation Angle.The results show that when the beam transmission Angle of 0.1 degrees deviation occurs,the output signal changes more than 11 dB,beam deviation Angle monitoring sensitivity is greater than 0.008 degrees/dB.