{'fraction_non_alphanumeric': 0.024390243902439025, 'fraction_numerical': 0.0023228803716608595, 'mean_word_length': 5.951612903225806, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Analysis of accuracy error and distortion in an operationally passive interferometric demodulation technique

Many architectures of fiber Bragg grating (FBG) interrogation systems used for mechanical motion (strain, acceleration, etc.) detection utilize interferometry for some part of the demodulation process. Using a hybrid Mach-Zehnder/tunable filter/3-by-3 coupler system architecture as a testbed, this paper examines error sources in the demodulation process giving rise to both/either accuracy and/or resolution degradation in the demodulated output. In particular, realizations of degradation metrics such as noise rise and harmonic distortion are reported due to inaccuracy in demodulation parameters, such as coupler parameters or photodetector voltages. Error models are developed where appropriate for comparison between prediction and measurement.