Complex decision of microwave radar antenna switch speed problem

Microwave antenna switches are used usually for transmit-receive decoupling, artificial load-antenna decoupling, receiver-receiver decoupling and transmitter-transmitter decoupling. The design of microwave antenna switches meets with contradictory demands. One of them is the contradiction between channel switch speed and high microwave switching power. At the same time there are limits on bandwidth, main power supply, cost, weight and size. At the present time the PIN-diode is the most convenient device for average power antenna switch design. Compared with the FET transistor, the PIN-diode is low cost, offers low parasitic capacitance and spurious inductance, and higher reverse-bias breakdown voltage. However, the PIN-diode has lower high-speed switching and requires more control current. In order to overcome the contradictory demands, a few design approaches are proposed.