Microwave Power Combiner Design Study

To guarantee the transmission distance, the pending transmission signal should be disposed by a series of power amplifications to obtain adequate power before it be send to transmitting antenna in the wireless transmitting apparatus. The single equipment of electrovacuum can provide biggish output power, but it is restricted to application in missile launch system with harder machining, higher voltage, bigger size and weight. At one time, the solid state power devices are advantages of small volume, light weight, high reliability, low voltage, convenient maintenance, good characteristic of thermal adaptation and so on. The technology of power combining, which superimpose in phase the output power of multipath solid state power devices, is one of the efficient path to obtain the higher output power.In this thesis, the usual power combining techniques have been reviewed and summarized, including on-chip, circuit and special techniques. The research significance and development trend of high-power combining techniques are clarified. The power combining devices and the entire combining system mainly aiming at solid state circuit has been investigated. Some creative ideas have been proposed. The main results are as follows:1.The ingredients limiting power capability and depress combining efficiency in the whole system have been discussed. The infection of the dimension of microstrip line to power capability of devices and the power capability of isolate resistor has been investigated in detail.2.The method of even- and odd-mode is adopted to design the two sections 4 in 1 microstrip line power combiner. And the assistant software Advance Design System (ADS) is used to optimize and simulate. The simulated results are analyzed in detail to obtain the wider bandwidth and lower transmission loss. 3.The combiner is produced according to the dimension which is provided by ADS. The experimental and simulated results of S-parameter are anastomosing. The bandwidth achieves 50% and the combined efficiency is above 90%.