This letter presents a compact Ka -band 4-bit switch-type phase shifter with low group delay deviation (GDD) using 28-nm CMOS technology. A magnetically coupled all-pass network (APN) configuration is employed to achieve both equal and flat group delay characteristics versus frequency at each phase state. The measured rms phase error is 1.2°, and the gain error is 1.1 dB at 33 GHz. The average measured insertion loss is 12.8 dB at 33 GHz, and the input and output return losses are both lower than -10 dB from 29 to 37 GHz. The fabricated phase shifter has a compact size of 0.08 mm2 excluding pads, low GDD of ±4 ps, and rms group delay error of < 2.2 ps between 16 phase states from 29 to 37 GHz. The proposed Ka -band phase shifter has the lowest GDD per bandwidth (GDD/BW) compared with other reported passive phase shifters.
Bibliographical noteFunding Information:
Manuscript received January 28, 2020; accepted February 9, 2020. Date of publication February 27, 2020; date of current version April 8, 2020. This work was supported in part by Yonsei Samsung Strategy Research Center (YSSRC), in part by the National Research Foundation of Korea (NRF), funded by the Ministry of Science and ICT through the Space Core Technology Program under Grant 2017M1A3A3A02016255, and in part by IDEC for CAD Software. (Corresponding author: Byung-Wook Min.) The authors are with the Department of Electrical and Electronic Engineering, Yonsei University, Seoul 120-749, South Korea (e-mail: email@example.com).
All Science Journal Classification (ASJC) codes
- Condensed Matter Physics
- Electrical and Electronic Engineering