The Research Of The PIN Diode Single Pole Double Throw Switch In Millimeter-wave Band

Millimeter-wave Switch is a kind of the millimeter-wave control circuits, it is widely applied in receiving protection of pulse radar and radio modulator, and it's also one of the very important parts of radar and test system. Single Pole Double Throw Switch (SPDT) mainly complete the conversion of the signal between difference channels, the control element in common use is PIN diode and GaAs MESFET. This thesis mainly discusses the millimeter-wave fin-line PIN diode SPDT. This kind of switch use the unilateral fin-line as the basic transmission line, the beam lead PIN diode of ALPHA Co. Ltd is the control element, there is two diodes in each channel and they are welded in circuit in parallel connection. The input and output use the standard rectangle wave-guide, the transition between rectangle wave-guide and fin-line is continuous gradual change line, and it has good capability of matching. Because of the influence of some parasitic parameter in PIN diode and circuits, some measure must be taken to compensate the circuits. Moreover, the manufacturing technic and assembly technology is also one of the important factors that influence the capability of the switch.This thesis mainly analyze the structure of switch the circuit's form and some of manufacturing technic. Under the given frequency band, the switch has flat capability of insert loss and isolation, and can satisfy the need of millimeter-wave system. This kind of switch has small cubage and high dependability. It is easy to integration, and has wide foreground in millimeter-wave band.