In this letter, a tunable protection switch device using open stubs for X-band low-noise amplifiers (LNAs) is proposed. The protection switch is implemented using p-i-n diodes. As the parasitic inductance in the p-i-n diodes may degrade the protection performance, tunable open stubs are attached to these diodes to obtain a grounding effect. The performance is optimized for the desired frequency band by adjusting the lengths of the microstrip line open stubs. The designed LNA protection switch is fabricated and measured, and sufficient isolation is obtained for a 200 MHz operating band. The proposed protection switch is suitable for solid-state power amplifier radars in which the LNAs need to be protected from relatively long pulses.
Bibliographical noteFunding Information:
Manuscript received May 19, 2017; revised July 17, 2017; accepted August 10, 2017. Date of publication September 26, 2017; date of current version November 6, 2017. This work was supported in part by the Ministry of Science and ICT (MSIT), South Korea, through the ICT Consilience Creative Program under Grant IITP-2017-2017-0-01015, supervised by the Institute for Information and Communications Technology Promotion (IITP), in part by the Civil Military Technology Cooperation Program, in part by the Electronic Warfare Research Center, Gwangju Institute of Science and Technology, in part by the Defense Acquisition Program Administration, in part by the Agency for Defense Development, and in part by IITP Grant funded by the Korea Government (MSIT) under Grant 2017-0-00286, a development of SAR for small sized UAV. (Corresponding author: Min-Ho Ka.) The authors are with the School of Integrated Technology, Yonsei Institute of Convergence Technology, Yonsei University, Incheon 21983, South Korea (e-mail: firstname.lastname@example.org).
All Science Journal Classification (ASJC) codes
- Condensed Matter Physics
- Electrical and Electronic Engineering