Microstrip parallel‐line coupler to perform broadband optically controlled phase‐shifting

This paper presents an optically controlled broadband phase-shifter using a parallel-line coupler, that takes advantage of high-resistivity silicon photo-absorption at 840 nm. A continuously variable phase-shifting of 120° is achieved at 11 GHz with Δ|S21| < 5 dB and with |S11| < −15 dB in a large frequency band (6–15 GHz). © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 47: 570–573, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21232