{'fraction_non_alphanumeric': 0.028089887640449437, 'fraction_numerical': 0.007022471910112359, 'mean_word_length': 5.4818181818181815, '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}}
Two-dimensional distribution measurement of in-plane velocity component using bias-frequency spatial encoding

Abstract. We propose a differential laser Doppler velocimeter (LDV) for two-dimensional (2D) distribution measurements of the in-plane velocity component based on bias-frequency spatial encoding. Using two crossing beam arrays, the structure can effectively assign bias frequencies to the measurement points over a 2D area. As a feasibility study of the proposed method, velocity distribution measurements were conducted using a 4  ×  4-channel optical setup. The experimental results indicate that the proposed method could successfully measure the 2D distribution of the in-plane velocity component.