Multichannel Transmitting System Based on High-Temperature Superconducting Phase Shifter

• Published in: IEEE transactions on applied superconductivity Vol. 30; no. 8; pp. 1 - 6
• Main Authors: Dahan, Yakir, Holdengreber, Eldad, Mizrahi, Moshe, Schacham, Shmuel E., Farber, Eliyahu
• Format: Journal Article
• Language: English
• Published: New York IEEE 01-12-2020; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Capacitance; Capacitors; Communication systems; Couplers; high power trans-mission; High temperature superconductors; high-temperature superconductors (HTSC); Junctions; microstrip directional couplers; Phase matching; Phase shifters; Sapphire; software-define radio (SDR); Substrates; superconducting devices; Superconducting microwave devices; Superconductivity; Very high frequencies; VHF band; YBCO superconductors; Yttrium barium copper oxide
• ISSN: 1051-8223; 1558-2515
• DOI: 10.1109/TASC.2020.3028278

Multichannel very high frequency (VHF) high-power transmission system, based on a 90 ° , high-temperature superconductor YBa 2 Cu 3 O 7 (YBCO) hybrid coupler is presented. The small dimension coupler performs as a phase shifter utilized for matching several different channels into a single junction. The planar coupler was implemented in a microstrip geometry by patterning a thin layer of YBCO on a sapphire substrate. Superconductivity is essential for obtaining low losses and high-power capabilities. The system was tested for power transmission of up to 52.9 dBm over a period of several hours. No deterioration with time was recorded. Maximum losses of 0.8 dB per channel were measured. The proposed system shows high-precision tuning capabilities, a critical feature for multichannel systems.