Event Details
High Resolution Optical Coherent-Channel Analyzer Using Balanced-Coherent Detection and Temperature-Tuned DFB Laser as Local Oscillator
Presenter: Rejoy Isaac
Supervisor: Dr. Thomas E. Darcie
Date: Wed, August 25, 2010
Time: 09:30:00 - 10:30:00
Place: EOW 430
ABSTRACT
Abstract:
We built and tested a high resolution (demonstrated 100MHz) optical coherent channel analyzer (CCA) using heterodyne detection with a temperature-tuned distributed-feedback (DFB) laser as a local oscillator. This analyzer uses balanced coherent detection to provide frequency resolution far superior (100 times) than that of grating based optical spectrum analyzers. The use of a DFB laser as the local oscillator offers potentially substantial cost and size reduction relative to existing high resolution spectrum analyzers using external cavity lasers, but at the expense of wavelength scanning range. We have studied the impact of the phase noise of the local oscillator (DFB laser) used on the resolution of the CCA. We have also derived an end-to-end system model including the impact of square-law IF power detection on sensitivity. The predicted signal-to-noise ratio is verified experimentally showing a sensitivity of-95dBm over a tuning range of over 200GHz.