Ka-band Solid-state Pulsed Power Amplifier Technology

With the development and utilization of the electromagnetic spectrum, millimeter wave band has become the key band for radar, navigation, satellite communications, and others. Especially in military applications, a lot of special requirements have been taken forward to the millimeter-wave power amplifiers in order to achieve longer distance, stronger anti-interference, more hidden and greater stability,. Nowadays, the pulse modulation of microwave power amplifier based on TWT has a relatively mature technology, but the pulse modulation of microwave power amplifier based on solid-state Millimeter-wave power amplifier research is still relatively weak.Firstly, the driver program of high-speed power MOSFET has been proposed by the theoretical analysis of pulse modulation source, and the high-speed window comparator and symmetric totem-driven technology has been taken to achieve high-power high-speed pulse modulation source. The test result of the sample shows that the rise and fall edge of the pulse is less than 4.5ns, the pulse width adjust rang from 150ns to 1.6μs, the pulse repetition rate adjust from 500Hz to 560kHz continuously, the peak Current is up to 6.1 A in the 1.5 ohm load for the 12V of the power supply voltage.A combining network has been taken forward by the principle analysis and research of the waveguide directional couplers technology and other key technologies, which can be used in any way.The three-way power combining network has been designed by this way, and the problem of the consistency of the phase and amplitude has been solved. The test result of the sample shows that the separation between each branch is up to-18dB, and synthetic loss is better than-0.4dB. A three-way power combining amplifier has been making by the three-way power combining network, which average c efficiency can be up to 84.4%, and has gained good stability properties.Finally the solid-state millimeter-wave power amplifier has been drain modulated by the power pulse source, the peak power output of the pulse millimeter-wave is up to 2.7W, the rise and fall edge of the pulse envelope are better than 28ns, the stability and top landed of the pulse envelope are less than 10%, the stability of pulse envelope of the repetition rate is better than 5%, which can meet actual project requirements.Take into account the needs of practical application, the adaptability of the structure was fully considered, the pulsed source modules can be in parallel to get greater output current, the pulsed source module can be in series to gain a higher Voltage pulse.