{'fraction_non_alphanumeric': 0.023214285714285715, 'fraction_numerical': 0.0, 'mean_word_length': 5.442528735632184, '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}}
Experimental Study and Application of Response Mask Invariant Characteristic for Generalized Visible Light Communication Channel

In this paper, we describe a generalized visible light communication (VLC) channel, which consists of the frequency responses of the light emitting diode (LED), the wireless optical channel, and the photo detector (PD). Based on the theoretical analysis of the generalized VLC channel, we found the response mask invariant characteristic (RMIC) under the condition of strong line of sight components, which means the shape of frequency response of generalized VLC channel is time-independent and invariant at different distances of the transceivers, different emitting angles of the LED and different incident angles of the PD. Depending on the RMIC, the shapes of received spectrum and signal-to-noise rate are also invariant. The experimental platform was set up to verify the proposed RMIC. Furthermore, a predefined VLC system with a new channel feedback method is described, both the complexity and time cost of feedback can greatly reduce through the proposed channel feedback method.