X-Band High-Power And High-Efficiency Power Amplifier Technology Research

Power amplification is a key technology in the field of microwave, and amplifiers are also key components of most microwave systems. Solid-state power amplifier is commonly used in radar, electronic countermeasure, wireless communication equipment, special test system, etc., and whose overall trend is towards the development of higher power at higher frequencies. However, the output of single device is increasingly difficult to meet the diverse mission requirements of amplifier modules. Power-combining technique is one concrete way to achieve this goal, it has important research value and wide perspective of development.This is mainly aimed at researching high power, high efficiency and broadband microwave power combining technique. After a brief introduction to the background of it and analyzing the parameters such as the output power and the combining efficiency, the main research work of this thesis is carried out.Firstly, a gradient line Wilkinson divider is used to improve the operating bandwidth. It has made it cover the entire X band without sacrificing the simple structure and small loss. The test results show that the most band insertion loss is less than 0.2dB, and the amplitudes and phase of the output ports have a good consistency. The return loss of input port is better than 14.6dB. We processed new four-way power divider/combiner network based on the single cosine squared gradient line Wilkinson power spliter. The advantage of this structure is that by reasonable layout and wiring the network we can improve the combining efficiency. Physical testing shows that the return loss of input port is better than 13dB, the insertion loss of combining network is between 0.3dB and 0.4dB, combining efficiency is higher than 91%.It has designed a new type of waveguide magic T structure to make the relative bandwidth better than 25%, and processed a spatial power divider/combiner network which is based on the improved waveguide magic T. Compared with microstrip circuits, this structure has smaller insertion loss and higher combining efficiency. The test results show that the return loss of input port is better than 13dB. The whole insertion loss of network is between 0.25 and 0.5dB, combining efficiency is higher than 94%.Finally, by using improved waveguide magic T combiner network we achieve the four way X-band Power combining Amplifier through a reasonable choice of domestic power amplifier chips. After testing, in the whole X-band, the Saturation output power of this power-combining amplifier is greater than 178W, the power gain is greater than 36dB, combining efficiency is better than 89% and the power added efficiency is better than 39%. This result achieved the indicators of high power, high efficiency and broadband, meeted the design requirements.