Integrated Optical Six-Port Reflectometer in Silicon on Insulator

• Published in: Journal of lightwave technology Vol. 27; no. 23; pp. 5405 - 5409
• Main Authors: Halir, R., Ortega-Moux, A., Molina-Fernandez, I., Wanguemert-Perez, J.G., Cheben, P., Dan-Xia Xu, Lamontagne, B., Janz, S.
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01.12.2009; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Applied sciences; Circuit properties; Couplers; Devices; Electric, optical and optoelectronic circuits; Electronics; Etching; Exact sciences and technology; Insulators; Integrated optics; Integrated optics. Optical fibers and wave guides; Interference; Measurement; Microwave frequencies; Noise levels; Optical and optoelectronic circuits; Optical fiber communications; optical interferometry; optical network analysis; Optical receivers; Optical reflection; Optical telecommunications; Phase error; Phase measurement; planar lightwave circuit (PLC); Power measurement; Reflectometers; Silicon; Silicon on insulator technology; six-port reflectometer; Telecommunications; Telecommunications and information theory; Testing; Theoretical study. Circuits analysis and design; Integrated optics; Measurement; Optical interferometry; planar lightwave circuit (PLC); optical network analysis; Implementation; Wave reflection; Silicon on insulator technology; Optical fiber network; Linear combination; Diversity reception; Network analysis; Optical planar waveguides; Multimode interference device; Optical receiver; Optical fiber communication; Optical waveguide; Waveguide couplers; Optical reflection; six-port reflectometer; Reflectometer; Reflectance; Planar technology
• ISSN: 0733-8724; 1558-2213
• DOI: 10.1109/JLT.2009.2031613

The six-port reflectometer technique enables simple and accurate measurement of optical reflection coefficients in both magnitude and phase. The reflection coefficient is computed from four power measurements of linear combinations of the waves incident and reflected from the device under test. While the six-port technique is very successful at microwave frequencies and conceptually related to coherent optical phase diversity receivers, no optical implementations have been reported so far. In this paper, we present an experimental characterization of an optical six-port reflectometer composed of three multimode interference couplers, fabricated with a single etch step in silicon on insulator. Measurements are performed using a novel technique with a simple setup. The six-port combines the incident and reflected waves with magnitude and phase errors less than plusmn0.5 dB and plusmn6deg in the 1485-1575 nm band.