High Frequency High-pressure Solid Floating Panels Modulator

Floating deck modulator (FDM) has many advantages such as perfect output wave, low power, low voltage, and flexible wave variety. So it is widely used in middle and small power microwave tube. Tube is used to switch in former project. It leads modulator circuit complex and low reliability. In addition, the volume and weight of modulator increase along with the Pulse Repetition frequency of radar increase. Mostly Pulse Repetition frequency in modulator whose switch is made up of tube is less than 10kHz.With the development of semiconductor switching equipments, especially the development of power Mosfets and IGBT (Insulated Gate Bipolar Transistor), it becomes imaginable that high-frequency high voltage FDM is made up of all-solid-state switching tubes. A Solid state 6kV/110kHz floating deck grid modulator for multi-beam klystron transmitter using series power mosfets as modulating switches is described in this paper. Modulator circuit topology is briefed. The characteristic of wave tube using in the modulator is described . The characteristic of Mosfets switching tube which is the key parts of modulator is briefed., the series application of Mosfets, the driving circuit of switching tube, the bias voltage power supply in modulator, and protecting circuit are presented in detail. The experimentation method and results are introduced in the end. The results indicate that the modulator which has already succeed to use in drone system .