Email Document Reference

Enter your email address below and the reference for this document will be sent to shortly from webmaster@ceesi.com.

Title: Lower Cost Methods Of Measuring Optical Bandwidth
Author: Thomas R. Hettenhouser
Source: 2005 Measurement Science Conference
Year Published: 2005
Abstract: Third party calibration laboratories need cost effective, multi-purpose test equipment while maintaining high quality measurements. Current methods for proving the optical bandwidth of reference receivers include time-domain impulse response measurement and frequency-domain heterodyne measurement. In the time-domain measurement, a mode-locked laser is used to generate sub-picosecond optical pulses. The optical pulse is recovered in the time domain, using the reference receiver under test, and Fourier transformed into the frequency domain, giving both magnitude and phase information on the reference receiver. The mode-locked laser is expensive and has few additional uses within a calibration laboratory. Also, this method is difficult for laboratories that work on multiple model types as the data must be gathered from the device under test (DUT) and some do not have automated output to the math program. A simpler method of proving optical bandwidth is the heterodyne method. This method has been shown to be accurate by various national measurement institutes (NMI) and requires a minimum of signal processing. The lasers used need to be highly stable. The concept is that if two lasers of the same power level and polarization are mixed together, as the wavelength of one is tuned slightly off of the other, a microwave modulation signal will develop. As long as the power level of both lasers remains the same as the tuned laser is adjusted, the resultant modulation will be flat with frequency. It is our intent to work with heterodyne method of proving optical bandwidth and experiment with lower cost tunable and fixed lasers to develop an acceptable test that meets our customers uncertainty needs. This paper will cover both the success and failures of these experiments.

In order to prevent spam and automated file downloads for documents within the Measurement Library, please follow the instructions below and then you will be able to email a reference to this article.