A 250W 2.45GHZ-band solid-state pulsed source

The solid-state microwave transmitters and sources have found wider and wider applications not only in radar systems, but also in many branch of industry and medicine. This paper presents development of a 250W compact solid-state pulse synthesized source operating around 2.45GHz, for medical equipment as an exciter of accelerator’s cavity. The source includes programmable PLL synthesizer, pulse former, 4-stage class C amplifier, DC supply and control block with microcontroller. The 250W peak power with a pulse width up to 15μs and 10% duty cycle is achieved by combining in a balanced configuration two 150W high power amplifiers. The output power level is controlled within 7dB dynamic range. The power droop during RF-pulse is less than 0.1dB for1% duty operation and 70ns pulse fall/rise time in the whole output power dynamic range The PLL synthesizer achieves more than 10⁻⁷ long-term stability (including pulling effect) and −80dBc/Hz@1kHz phase noises.