W Band Switch Pin Tube

Millimeter-wave switch is widely applied in the fields of radar, communications, navigation, surveying and electronic countermeasures, plays a central role in the control systems of millimeter wave, PIN switch has many advantages, such as simple struchture, small size, high performance, low cost and so on, occupies an extremely important role in the millimeter-wave switch, so PIN diode swich’s research work is very important.In this dissertation, under the sonsideration of the requirements of low insertion loss, high isolation, based on the transfer matrix and unilateral finline theory, it discuss the finline junction structure with the rectangular waveguide equivalent simulation method; based on multiple PIN diode casade method, it made an in-depth study to achieve the switch with low insertion loss and high isolation performance, and we successfully designed a W-band single pole single throw and single pole double throws switch with filter method. The test results show us that the single pole single throw switch’s insertion loss less than2.5dB, isolation more than35dB in90GHz-95GHz; the single pole double throw switch is designed with Y-shaped junction finline, with the insertion loss less than5.5dB and isolation more than24dB in90GHz-95GHz; While the single pole double throw switch designed with the gradient finlive junction structure aquires an insertion loss of no more than3.8dB and an isolation of more than33dB in90GHz-95GHz, which has an improved significantly performance compared with the traditional Y-shaped junction finline switch.In addition, using MMIC switch chip and micro strip probe transition structure, a SPDT switch successful designed with the insertion loss lower than3.5dB, isolation higher than35dB in90GHz-95GHz. A switch group is composed of three MMIC SPDT, and plays a key role in muli-channel system.