Hadamard–Viterbi Joint Soft Decoding for MFSK Underwater Acoustic Communications

Autor: Fei-Yun Wu, Tian Tian, Ben-Xue Su, Yan-Chong Song
Jazyk: angličtina
Rok vydání: 2022
Předmět:
Zdroj: Remote Sensing, Vol 14, Iss 23, p 6038 (2022)
Druh dokumentu: article
ISSN: 2072-4292
DOI: 10.3390/rs14236038
Popis: Multiple Frequency-Shift Keying (MFSK) has been used widely for underwater acoustic communications due to its low complexity and channel robustness. However, the traditional MFSK has the limitation of a low bit rate compared with coherent acoustic communication. To increase the bit rate, this study designs a new MFSK with the concept of orthogonal frequency division multiplexing (OFDM). We also adopt a channel-concatenated coding to resist the multipath interference and design the iterative joint decoding. The channel-concatenated coding consists of a Hadamard code and a convolutional code. Correspondingly, the iterative joint decoding uses the Hadamard–Viterbi joint soft decoding framework with a newly designed branch metric, which uses the Hadamard structure. As an important preprocessing link for a received signal, frame synchronization and Doppler compensation are also described in detail in this study. Simulations and experiments are conducted to show the effectiveness of the proposed MFSK underwater acoustic communications.
Databáze: Directory of Open Access Journals
Nepřihlášeným uživatelům se plný text nezobrazuje