{'fraction_non_alphanumeric': 0.028684470820969338, 'fraction_numerical': 0.02373887240356083, 'mean_word_length': 4.8497109826589595, '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}}
Delivering high quality, secure speech communication through low data rate 802.15.4 WPAN

IEEE 802.15.4 is a wireless personal area network (WPAN) for low data-rate and duty-cycle applications. How this simple network can also be used for high quality, secure speech communication is described in this paper. The key to achieve this lies in how the various features can be packed into the low bandwidth structure that has been allocated in this protocol. A low bandwidth high quality speech vocoder such as the advanced multiband excitation (AMBE) from DVSI has been found suitable to be used in our evaluation. Guaranteed time slot (GTS) has been reserved in the superframe structure to ensure continuous and uninterrupted audio streaming. For high security, the inherently 802.15.4 built in advanced encryption standard (AES128) and message integrity code (MIC) 128 bits algorithms are utilized. At the end of the paper, a methodology to channel speech more efficiently by forming GTS dynamically is proposed.