The Research Of A Novel High Power Microwave Phase Shifter

Due to inherent limitation of High-power microwave(HPM)generation mechanism,a single HPM source has a limited power.To obtain higher power output,power synthesis technology and scanning antenna technology are adopted.So high power microwave phase shifter acting as a key device in phase control and power synthesis has become an urgent important issue to investigate.Depend on the practical application of high power synthesis system,compact size,high power capacity and easy operation of phase shifters are required.In this dissertation,a novel phase shifter called turnstiles phase shifter,has been proposed,consisting of compact cross circular polarizer and circular arc irises circular polarizer.The detailed contents include the followings:1.A compact cross circular polarizer has been investigated.To realize circular polarization,the relationship between structure parameters and microwave frequency has been deduced.Based on preliminary theoretical analysis,detailed numerical simulation study was carried out.To improve structure compactness property,the compact ten-shaped circular polarizer which has higher transmission efficiency and port isolation was designed.Simulation indicates that transmission of the circular polarizer exceeds 99.7% with axial ratio about 0.06 dB at 1.575 GHz,and the transmission efficiency exceeds 97.5% with axial ratio less than 2.5 dB in the frequency range from 1.53~1.62 GHz and the maximum allowed input power for this circular polarizer could be more than 2 GW.2.A circular arc irises circular polarizer has been investigated.The relationship between the normalized electric and transmission coefficient and the output phase of the curved diaphragm is deduced by the equivalent circuit theory,as well as the transmission matrix of arc diaphragm.On this basis,the circular polarization device with three row arc diaphragm working at 1.575 GHz is designed and verified by simulation.The results demonstrate that the circular polarizer can convert the coaxial TEM mode to circularly polarized TE11 mode effectively at center frequency with transmission efficiency of 99.9% and axial ratio about 0.015 dB,the transmission efficiency exceeds 97.0% with axial ratio less than 3 d B in the frequency range from 1.545~1.62 GHz,the maximum allowed input power for this circular polarizer could be more than 2.8 GW.3.The turnstile phase shifter has been investigated.Simulation indicates the phase shifter can realize the arbitrary liner phase shift of 0~360 degree.At the center frequency of 1.575 GHz,the transmission efficiency is more than 98.8%;in the frequency range of 1.565~1.595 GHz,transmission efficiency exceeds 95%,the maximum allowed input power for this phase shifter could be 2.0 GW.4.Lower power experiments investigation are performed.The engineering design and manufacture of two kinds of circular polarization apparatus are carried out and the turnstile phase shifter is assembled for the low power experiment.The results suggest that,phase shifter works in a linear phase shift state.At the center frequency of 1.575 GHz,the average transmission efficiency is about 95%;in the frequency range of 1.568~1.592 GHz,transmission efficiency exceeds 91.8% to 98.1%.