@mastersthesis {9996,
	title = {Complex Optical (Amplitude and Phase) Device Characterization Tool},
	year = {2009},
	type = {mastersMS},
	abstract = {Optical communications has experienced a rapid development during the last decade. More\&nbsp;bandwidth can be acquired by decreasing the spacing of the optical channels or by increasing\&nbsp;the data rate. Characterization of the optical components and active monitoring of the network\&nbsp;calls for accurate measurement methods. The transfer function of optical components impactsthe performance of communication systems. Analysis and accurate measurement of the transfer\&nbsp;function is therefore essential in optimization of the performance of such systems.Chromatic dispersion of optical bers and frequency chirp of the laser transmitters set limits\&nbsp;for the data rate and transmission distance. Measurements of dispersion have traditionally\&nbsp;been performed using a Modulation Phase-Shift (MPS) method. When high RF modulation\&nbsp;frequencies are applied to achieve high resolution an alias error could be introduced. In this\&nbsp;thesis we introduce an apparatus for full complex-amplitude spectral characterization of opticalcomponents and bers. Based on a modication of the MPS method, we introduce a frequency\&nbsp;dither to the RF modulation drive, allowing us to detect small phase changes thus overcoming the\&nbsp;limitations imposed by the conventional MPS method. Its salient feature is high sensitivity phase\&nbsp;detection enabling the use of a low RF driving frequency as necessary for precise measurement\&nbsp;of components exhibiting fine spectral features such as microresonators and slow light devices.\&nbsp;We analyze the modied MPS technique using the traditional small signal approximation and\&nbsp;compare the results to a full analytic response of the MPS technique. The full analytic response\&nbsp;is useful for optimization of the proposed technique. The characterization apparatus has been\&nbsp;realized in our lab using commercially available optical and electrical components. We have\&nbsp;characterized experimentally the signals passing in the apparatus. Care was taken to prevent\&nbsp;higher RF tones (i.e. above 1st order) in the Mach-Zehnder Modulator (MZM) output field,\&nbsp;which could interfere with the desired measurement. Moreover, care was taken to prevent RF\&nbsp;leakages in the electronic circuitry, which could interfere with the measurement of weak signals.\&nbsp;We demonstrate the operation of the modified MPS at two operating points, demodulating with\&nbsp;either the same RF carrier or with a doubled one. We measured several component categories\&nbsp;and fibers to demonstrate the measurement technique. Finally, we conclude with the advantages\&nbsp;and disadvantages of the modified technique.},
	url = {http://hufind.huji.ac.il/Record/HUJ001515612},
	author = {Yoram Palti}
}
