L‐band 360° broad‐bandwidth monolithic analog phase shifter

Abstract

An L‐band 360° broad‐bandwidth analog phase shifter is designed using varactor. New design equations for expanding bandwidth and improving linear phase‐shift are derived and applied to performances optimization in one circuit. The analog phase shifter is fabricated using MIC and SMT technologies. At 1.2 ∼ 2.0 GHz (L‐band), total phase‐shift of 360° and linear deviation of less than ±2.5% were obtained, and the insertion loss varied less than 2 dB across the band. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 36: 164–166, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10709

Design for a linear voltage‐controlled 360°‐analog phase shifter

“…It offers stable wireless internet service without time or space limitations, but is hindered when the train is passing through a tunnel, which blocks direct access to the satellite signal. A tunnel is a typical shadowing area, in which a gap filler is required for better communication between the satellite and the wireless terminal of the Korean high-speed train network [1][2][3]. A gap filler system requires three antennas: one installed outside the tunnel (Antenna 1), one installed inside the tunnel (Antenna 2), and one installed on the train (Antenna 3).…”

“…In the design of a reflection-type phase shifter, the following factors should be considered: (1) phase-shift range, (2) attenuation ripple, (3) bandwidth requirement, and (4) linearity of phase shift versus the control voltage. Several methods have been made to satisfy these requirements [3], but none can satisfy all these four requirements in a single circuit. Thus, the phase shifter designers have to make trade-offs among these requirements.…”