Open AccessIterative receiver for the triple differential PSK modulation in the time‐varying underwater acoustic communications
Author(s) -
Cui Hongyu,
Liu Changxin,
Si Boyu,
Wu Jie,
Sun Dajun
Publication year - 2020
Publication title -
iet communications
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.355
H-Index - 62
eISSN - 1751-8636
pISSN - 1751-8628
DOI - 10.1049/iet-com.2020.0513
Subject(s) - demodulation , computer science , transmitter , direct sequence spread spectrum , phase shift keying , underwater acoustic communication , bit error rate , differential coding , modulation (music) , keying , transmission (telecommunications) , electronic engineering , spread spectrum , channel (broadcasting) , telecommunications , decoding methods , physics , underwater , acoustics , engineering , oceanography , geology
Due to the time‐varyingproperty of the underwater acoustic (UWA) channel, the significant Doppler spread will severely degrade the performance of direct‐sequence spread‐spectrum (DSSS) communications. The relative velocity variation between the transmitter and the receiver will cause both the phase rotation and the magnitude loss of correlation peak, during the long transmission of the DSSS packet. To solve this problem, the authors propose a novel transceiver design for the UWA DSSS communications. At the transmitter, the triple differential phase shift keying (D3 PSK) modulation is adopted to overcome the phase rotation, whereas the phase noise will be amplified resulting in the signal‐to‐noise ratio (SNR) loss. At the receiver, the improved bit‐interleaved coded modulation with iterative decoding algorithm for D3 PSK is used to recover the SNR loss, in which the D3 PSK demodulator is treated as the convolutional decoder, and the linear prediction is adopted to track the channel variation. Furthermore, an adaptive selection of local reference signal is also applied to recover the correlation loss. Theoretical simulation shows that the proposed transceiver can effectively mitigate the performance loss caused by the motion acceleration, and the performance gain is significant over the conventional.