Advanced Methods for the Measurement of Chromatic Dispersion at Optical Frequencies
Tutor / directorSantos Blanco, M. Concepción
Document typeMaster thesis
Rights accessOpen Access
Currently, most networks are hybrid, combining fiber with copper wire, but the goal is for them to be completely of fiber. Like any other transmission medium, using fiber has some drawbacks, being chromatic dispersion one of the most relevant, because it affects the transmission capacity of the fiber, and since this transmission medium is widely used is important to study how to compensate the dispersion, in order to do it, first we must know its value, which brings us to the topic to be discussed in this Master Thesis: Advanced Methods for the Measurement of Chromatic Dispersion at Optical Frequencies. To implement the methods, we will first study the phenomenon of dispersion, and how to observe its effect on the phase and envelope of the signal. Then, we will study 4 methods of measurements based on radiofrequency modulation of the optical carrier signal. Before, we will need to study the performance, configuration and modes of an essential element in the study of the methods, the Mach-Zehnder modulator, which performs the RF modulation of the optical carrier. The first two methods, known as the standard methods are: Peucheret and MPSM. Both of them find the dispersion through information contained in the phase and amplitude, respectively, of the modulated signal. These two methods generally use the modulator in push-pull mode. The 2 new methods presented here: ABCM and RF-SCAN differ mainly from the previous because of their use of the modulator in asymmetric mode. But like the previous methods they also obtain the information needed to calculate the dispersion in the amplitude of the modulated signal, in the case of ABCM, and RF-SCAN uses both amplitude and phase for a more accurate measurement.
Exploring different techniques for measurement of chromatic dispersion at optical frequencies and looking for novel methods to improve some of their limitations.