Antenna integration with a waveguide photodetector for high capacity wireless communications

Abstract

This paper proposes the integration of an antenna with a photodetector for high capacity wireless communications. A waveguide photodetector (WGPD), illuminated on the side, is used to convert the RF‐modulated optical power into a microwave signal. That microwave signal is used to feed an antenna built on the same plane as the photodetector. The WGPD is a standard p‐i‐n device grown on a semi‐insulating InP. The performance of this RF/photonic antenna in the frequency range 17–20 GHz is studied theoretically and experimentally. An equivalent circuit model for the WGPD is developed to predict the photodetector impedance as a function of frequency. The photodetector is matched to the input impedance of the antenna. The agreement between measurement and the circuit model results for the WGPD impedance is very good. It is envisioned that a large number of such RF/Photonic antenna elements could be networked together into a star configuration, feeding in and out of a radio hub. © 2002 Wiley Periodicals, Inc. Microwave Opt Technol Lett 35: 179–184, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10550