{'fraction_non_alphanumeric': 0.03125, 'fraction_numerical': 0.004934210526315789, 'mean_word_length': 5.151515151515151, '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}}
Multilevel Control Signaling for Hybrid ARQ

In this paper, we propose and analyze a multi-level acknowledgement scheme for hybrid ARQ (H-ARQ) systems, which modifies a general ACK/NAK signals to represent multilevel information. For instance, the other signals except the ACK/NAK signals may be used for scheduling of retransmission in H-ARQ scheme, which results in increasing the resolution of uplink channel estimation signals. Simulation results demonstrate that, when the retransmission interval is set to optimal length, the proposed H-ARQ scheme shows 0.5-2 dB gain with properly selected parameters.