Research On Broadband Phase Shifting And Equalization Amplifier Modules

The microwave power module combines the low noise,high gain and small size characteristics of a microwave solid state amplifier with the high efficiency and high power of a travelling wave tube amplifier,and is of great importance in the new generation of electronic warfare and satellite communication systems.The amplifier is driven by a power front-end,consisting mainly of a solid-state power amplifier and a gain equalizer,which provides input power and gain equalization for the travelling wave tube amplifier,giving the tube a flatter output power.With the ongoing development of science and technology today,the complex and diverse needs of the solid-state drive front-end are putting higher requirements on it,including high power,small size,high efficiency,ultra-broadband,reliability,and so on,as well as driving the gain equalizer towards miniaturization and new structures to accommodate complex equalization curves.This thesis first introduces the relevant research progress of microwave power modules at domestic and international level based on the background of the issue,and then analyses the working principle of gain equalizers.In view of the difficulty of miniaturization of microstrip lines gain equalizer in low frequency and the inability of the traditional defective ground structure to retain the complete ground plane at the bottom,a microwave gain equalizer is designed using GCPW,which etches the spiral line defect on the top ground plane of GCPW and retains the complete bottom ground plane to achieve 8d B of equalization at 10.08 GHz,and the equalizer has a small transverse dimension with an overall size of 9.5mm×3.2mm×0.254 mm.The amplifier output power is not flat which will lead to the multiple peaks in the gain curve as well as difficult to match,this thesis utilizes the principle of vector synthesis to design a non-resonant gain equalizer,this structure takes advantage of both the power distribution and power synthesis of the branch line bridge and Wilkinson power splitter to vector superimpose the reflected signal,making it possible to achieve two peaks at 33.15 GHz and 37.5GHz in the Ka band which are both greater than 15 d B and the return loss is better than 12 d B.In response to the demands of travelling wave tubes(TWTS)active phased array radar,two phase shifting equalization amplifier driver modules have been completed,whose operating bands are 8 to 18 GHz and 32 to 40 GHz respectively.The 8 to 18 GHz module has a maximum output power of 30.9 d Bm,an equalization measure of 15.5d B,an equalization accuracy of-1.29 d B and a phase shifting RMS error less than 6°.The 32 to 40GHz module adopts a discrete design,and after equalization,the module has a maximum output power of 27.08 d Bm,an equalization accuracy of-1.09 d B and an overall phase shifting RMS error less than 5°.The two modules both satisfy the design specifications.