{'fraction_non_alphanumeric': 0.041304347826086954, 'fraction_numerical': 0.0, 'mean_word_length': 4.829113924050633, '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}}
Hybrid ARQ protocols using space-time codes

Automatic repeat-request (ARQ) protocols using transmit diversity are investigated. The performance of space-time codes (STC) in a pure ARQ protocol (ST-ARQ) is first examined. Two hybrid ARQ schemes using STC are then proposed: space-time hybrid ARQ (ST-HARQ) and turbo space-time hybrid ARQ (TST-HARQ). For the ST-HARQ scheme, the previous transmitted packets are combined with the current received packet. In this scheme, the diversity gain is increased with every retransmission resulting in a higher probability of an accepted packet. For TST-HARQ, the transmitted packets are code combined and iteratively decoded. Performance analysis of ST-ARQ and ST-HARQ are approximated and shown to agree well with simulated results. TST-HARQ is shown to have the highest throughput efficiency compared to ST-HARQ and ST-ARQ in quasi-static and fast flat Rayleigh fading channels.