Multi-Channel Iterative FDE for Single Carrier Block Transmission over Underwater Acoustic Channels

• Published in: China communications Vol. 12; no. 8; pp. 55 - 61
• Main Authors: He, Chengbing, Huo, Siyu, Zhang, Qunfei, Wang, Han, Huang, Jianguo
• Format: Journal Article
• Language: English
• Published: China Institute of Communications 01.08.2015; School of Marine Science and Technology, Northwestern Polytechnical University, Xi'an, Shaanxi, 710072, China
• Subjects: Binary phase shift keying; Bit error rate; Equalizers; Frequency-domain analysis; Receivers; Signal to noise ratio; underwater acoustic communication;single carrier; multi-channel frequency domain equalization; iterative processing; Underwater acoustics; 单载波; 块传输; 多通道接收机; 性能损失; 水声信道; 输出信噪比; 迭代; 频域均衡; multi-channel frequency domain equalization; iterative processing; single carrier; underwater acoustic communication
• ISSN: 1673-5447
• DOI: 10.1109/CC.2015.7224706

Recently, single carrier block transmission （SCBT） has received much attention in high-rate phase-coherent underwater acoustic communication. However, minimum-mean-square-error （MMSE） linear FDE may suffer performance loss in the severely time dispersive underwater acoustic channel. To combat the channel distortion, a novel multi-channel receiver with maximum ratio combining and a low complex T/4 fractional iterative frequency domain equalization （FDE） is investigated to improve diversity gain and the bit error rate （BER） performance. The proposed method has been verified by the real data from a lake underwater acoustic communication test in November 2011. At 1.8 km, the useful data rates are around 1500 and 3000 bits/ s for BPSK and QPSK respectively. The results show the improvements of system performance. Compared with MMSE FDE system, the output SNR improvement is 6.9 dB, and the BER is from 10.3 to no error bits for BPSK. The output SNR improvement is 5.3 dB, and the BER is from 1.91×10^-2 to 2.2×10^-4 for QPSK.