Open AccessHigh-accuracy photoreceiver frequency response measurements at 155 µm by use of a heterodyne phase-locked loop
Author(s) -
Tasshi Dennis,
Paul D. Hale
Publication year - 2011
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.19.020103
Subject(s) - heterodyne (poetry) , optics , heterodyne detection , beat (acoustics) , frequency response , physics , frequency modulation , phase locked loop , materials science , radio frequency , phase noise , laser , acoustics , telecommunications , computer science , electrical engineering , engineering
We demonstrate a high-accuracy heterodyne measurement system for characterizing the magnitude of the frequency response of high-speed 1.55 µm photoreceivers from 2 MHz to greater than 50 GHz. At measurement frequencies below 2 GHz, we employ a phase-locked loop with a double-heterodyne detection scheme, which enables precise tuning of the heterodyne beat frequency with an RF synthesizer. At frequencies above 2 GHz the system is operated in free-run mode with thermal tuning of the laser beat frequency. We estimate the measurement uncertainties for the low frequency range and compare the measured high-frequency response of a photoreceiver to a measurement using electro-optic sampling.