Highly Linear K-/Ka-Band SPDT Switch Based on Traveling-Wave Concept in a 150-nm GaN pHEMT Process

• Published in: IEEE microwave and wireless components letters Vol. 32; no. 8; pp. 987 - 990
• Main Authors: Kim, Taehun, Im, Hyemin, Lee, Suk-Hui, Kim, Ki-Jin, Park, Changkun
• Format: Journal Article
• Language: English
• Published: IEEE 01.08.2022
• Subjects: Gallium nitride (GaN); HEMTs; high linearity; Insertion loss; Logic gates; Loss measurement; millimeter-wave (mm-wave); single-pole double-throw (SPDT); switch; Switches; Switching circuits; traveling-wave; Wireless communication
• ISSN: 1531-1309; 1558-1764
• DOI: 10.1109/LMWC.2022.3161498

This letter presents a highly linear 18-42 GHz single-pole double-throw (SPDT) switch based on the traveling-wave concept for 5G applications. An RF switch for 5G applications requires low insertion loss, high isolation, and high linearity in both Tx/Rx modes. To achieve wideband performance and high linearity, the traveling-wave concept and a 150-nm GaN high electron mobility transistor (HEMT) process were used. The equivalent circuit of the SPDT switch was analyzed using the <inline-formula> <tex-math notation="LaTeX">S </tex-math></inline-formula>-parameter to suppress the loss and improve the isolation. The proposed SPDT switch operates with less than 2.0-dB of insertion loss and higher than 32.1-dB of isolation in a frequency range of 18-42 GHz, in both Tx/Rx modes. The measured input 1-dB compression point (IP 1dB ) is 47.5-49.5 dBm at 26-30 GHz. The chip size of the proposed SPDT, including pads, is 3.7 <inline-formula> <tex-math notation="LaTeX">\times </tex-math></inline-formula> 0.51 mm 2 .