Han Jing, Wang Yujie, Zhang Lingling, Leus Geert
School of Marine Science and Technology, Northwestern Polytechnical University, Xi'an 710072, China.
Faculty of Electrical Engineering, Mathematics and Computer Science, Delft University of Technology, Delft 2826 CD, The Netherlands.
J Acoust Soc Am. 2019 Jan;145(1):292. doi: 10.1121/1.5087131.
Orthogonal signal-division multiplexing (OSDM) is a recently emerging modulation scheme which, compared to conventional orthogonal frequency-division multiplexing, can effectively lower the peak-to-average power ratio and introduce intra-vector frequency diversity. In this paper, a time-domain oversampled OSDM system for underwater acoustic (UWA) communications is designed, where each OSDM vector is equivalently transmitted over multiple virtual channels, and thus an enhanced frequency diversity gain can be achieved. Moreover, at the receiver, zero vectors and frequency-shifted Chu sequences are used for Doppler compensation and channel estimation, respectively, while low-complexity per-vector equalization is performed based on the composite channel matrix factorization. Finally, the performance of the proposed OSDM system is evaluated through both numerical simulations and a short-range field experiment, and its effectiveness over time-varying UWA channels is confirmed.
正交信号分割复用（OSDM）是一种最近出现的调制方案，与传统的正交频分复用相比，它可以有效降低峰均功率比并引入矢量内频率分集。本文设计了一种用于水声（UWA）通信的时域过采样OSDM系统，其中每个OSDM矢量等效地在多个虚拟信道上传输，从而可以实现增强的频率分集增益。此外，在接收机处，零矢量和频移Chu序列分别用于多普勒补偿和信道估计，同时基于复合信道矩阵分解进行低复杂度的逐矢量均衡。最后，通过数值模拟和短距离现场实验对所提出的OSDM系统的性能进行了评估，并证实了其在时变UWA信道上的有效性。
