New method to improve the accuracy of group delay measurements using the phase-shift technique
نویسندگان
چکیده
We propose and demonstrate a novel method to improve the accuracy of measurements of group delays using the conventional phase-shift technique. In particular, the method allows for accurate reconstruction of the actual group delay when a high modulation frequency is employed to increase the timing resolution. The method is based on postprocessing of the measured data in a deconvolution operation with the instrument function of the measurement setup. We present practical examples of it for both fiber Bragg gratings and narrow-band thin-film filters. 2002 Elsevier Science B.V. All rights reserved.
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