An Acoustic OFDM System with Symbol-by-Symbol Doppler Compensation for Underwater Communication

We propose an acoustic OFDM system for underwater communication, specifically for vertical link communications such as between a robot in the sea bottom and a mother ship in the surface. The main contributions are (1) estimation of time varying Doppler shift using continual pilots in conjunction wit...

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Bibliographic Details
Main Authors: Tran MinhHai, Saotome Rie, Taisaku Suzuki, Tomohisa Wada
Format: Article
Language:English
Published: Hindawi Limited 2016-01-01
Series:The Scientific World Journal
Online Access:http://dx.doi.org/10.1155/2016/7528353
Description
Summary:We propose an acoustic OFDM system for underwater communication, specifically for vertical link communications such as between a robot in the sea bottom and a mother ship in the surface. The main contributions are (1) estimation of time varying Doppler shift using continual pilots in conjunction with monitoring the drift of Power Delay Profile and (2) symbol-by-symbol Doppler compensation in frequency domain by an ICI matrix representing nonuniform Doppler. In addition, we compare our proposal against a resampling method. Simulation and experimental results confirm that our system outperforms the resampling method when the velocity changes roughly over OFDM symbols. Overall, experimental results taken in Shizuoka, Japan, show our system using 16QAM, and 64QAM achieved a data throughput of 7.5 Kbit/sec with a transmitter moving at maximum 2 m/s, in a complicated trajectory, over 30 m vertically.
ISSN:2356-6140
1537-744X