The Research On Microwave Gain Equalizer

As the rapid development scientific and technological, the power transmitters which are in modern communications and radar systems are put forward increasing challenge. Higher output power and emission efficiency, better gain flatness, more economical cost have become the development trends of microwave power amplifiers in the radar systems. In other words, power amplifier module should have the characteristics of low cost, superior performance and high reliability in order to meet the needs of a variety of environments. Microwave gain equalizer is a good solution to high-power traveling wave tube which gain is not flat. It is playing an increasingly important role in radar systems. In this paper, we carried out more detailed research and feasibility studies about microwave gain equalizer. Then we had designed and tested two microwave gain equalizer.Based on microstrip transmission line theory and microwave gain equalizer theory, we had designed a microwave gain equalizer in 2~6 GHz which used in Microwave Power Module(MPM) make use of ADS and HFSS(High Frequency System Simulator) in this paper. The value of equalization is about 9 dB. Under the premise of accuracy of equalization, we had controlled 11 S and 22 S in-20 dB or less, achieved a breakthrough progress. And we were meet microwave gain equalizer miniaturization by changing the structure of the microstrip line. In the design process, we had studied and optimized the microstrip line gain equalizer’s design theory and methods deeply, discussion the impact of microstrip notch filter unit and loaded resistance relevant parameters on the attenuation, and summing up to convenient to improve design efficiency for engineering design in the future.Then based on resonator theory and microwave gain equalizer theory, we were design a waveguide type hole coupling gain equalizer of 33 ~ 35 GHz to balance high-power TWT gain make use of HFSS(High Frequency System Simulator). The value of equalization is about 13 dB. In the design process, we had improved circuit topology of millimeter-wave gain equalization, proposed a new circuit structure, and we proved the feasibility of this new structure make use of computer simulation and physical testing. Under the premise of accuracy of equalization, we had controlled 11 S and 22 S in-10 dB or less, achieved a breakthrough progress, proved the new structure can be well controlled VSWR. This paper provides a good foundation for millimeter wave gain equalizer design.