L-band High-power Liquid-cooled Solid-state Power Amplifier Components Developed

With the perpetual development of microwave solid state apparatus, solid state transmitter has many outstanding merit such as the high reliability, wide frequency, low work voltage, little fault probability, low cost of entirely life period, etc, which arouse one revolution of radar technique. Now, the developing level of solid-state transmitter has been the important sign of the radar technique level. As a result, the manufacture of solid state power amplifier(SSPA) module is more and more comprehensive. The SSPA of different modal radar and different frequency is same in designing principle although different in function, performance and figuration. Although SSPA has been tended to maturate in designing and fabrication, it has some pivotal technique deserved to be discussed. Enough recognition is required in engineering implement.The studying work in this paper is SSPA which for a sort of row radar transmitter by weighted amplitude and active decoy system equipped for this radar. Three power amplifiers are manufactured based on system requirements, such as final stage modules(1.5kW), front-stage modules(900W) and driving modules(35~200W) This three modules composed of diversified transmitters of radar and active decoy system. These transmitters'output peak power are 3.5kW, 2.4kW, 1.2kW, 0.8kW and 0.2kW respectively.Some datum indicates, single semiconductor element upgrades 10℃in temperature, it reduces 50 percent in dependability. The microwave power transistors are key apparatus in SSPA, which disperse heat matter turns to be one bottleneck of credible application. In order to assure effectively high credible work of power module, Module's effectively heat designing is our working keystone. Under the maximal work condition, the heat dissipation of a single transistor reaches 52.5W, the density of heat stream is 27.63W/cm2. In practice, it is not satisfied for the wind-cooling and adopted liquid cooling manner. It is first applied in our graduate school for liquid cooling power amplifier.