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Network-assisted underwater acoustic communications
Proceedings of the Seventh ACM International Conference on Underwater Networks and Systems - WUWNet '12, 2012For many underwater acoustic applications, the source and receiver systems carry a single transducer antenna. The lack of spatial diversity makes it difficult to carry out phase coherent communications. Using distributed nodes of an underwater acoustic network, this paper address phase coherent underwater acoustic communications using source diversity.
T. C. Yang 0001, Kevin D. Heaney
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Cooperative Transmission for Underwater Acoustic Communications
2008 IEEE International Conference on Communications, 2008Underwater acoustic channels normally have low data rate, long propagation delay, severe multipath effect, and time varying fading. Cooperative transmission is a new wireless communication technique in which diversity gain is achieved by utilizing relay nodes as virtual antennae.
Han, Zhu +2 more
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Bidirectional equalization for underwater acoustic communication
The Journal of the Acoustical Society of America, 2012The bidirectional decision feedback equalizer (BiDFE) that combines the outputs of a conventional decision feedback equalizer (DFE) and backward DFE can improve the performance of the conventional DFE by up to 1–2 dB based on simulations. In this letter, the BiDFE concept is extended to multichannel time reversal communications involving a DFE as a ...
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Beyond underwater acoustic communications
OCEANS 2011 IEEE - Spain, 2011The ability to communicate underwater using acoustic energy in place of electromagnetic energy is rapidly becoming commonplace. Indeed, vendors and academic researchers in many advanced countries are pursuing the development of acoustic modems. The emphasis often varies among these efforts: some, especially academic researchers, focus on increased ...
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Efficient use of bandwidth for underwater acoustic communication
The Journal of the Acoustical Society of America, 2013In a recent shallow water experiment, acoustic communication transmissions were carried out over the 10 to 32 kHz band in ∼100 m deep water over a 3 km range. A natural question is how best to utilize that bandwidth. In one multiband approach discussed previously, the band was divided into four smaller subbands that were processed independently using ...
H C, Song, W S, Hodgkiss
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On the physics of underwater acoustic communications
AIP Conference Proceedings, 2012Digital communications have been traditionally treated using signal processing approaches. Algorithm and performance is system-model dependent. For underwater acoustic communications, the system model is very complex due to the different channel environmental conditions which can vary rapidly with time, and are location dependent.
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Scalable OFDM design for underwater acoustic communications
2008 IEEE International Conference on Acoustics, Speech and Signal Processing, 2008Multicarrier modulation in the form of OFDM has been actively pursued for underwater acoustic communication recently. In this paper, we present a desirable property of OFDM that one signal design can be easily scaled to fit into different transmission bandwidths with negligible changes on the receiver.
Baosheng Li +3 more
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Asynchronous multiuser underwater acoustic communications (L)
The Journal of the Acoustical Society of America, 2012An asynchronous multiuser system is proposed to support multiple-access underwater communications without the use of code-division multiple-access or a feedback channel. The rich multipath channels experienced by spatially separated users will be sufficient to ensure separation of collided packets at the base station. The iterative receiver will employ
S E, Cho, H C, Song, W S, Hodgkiss
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Swell effect in shallow underwater acoustic communications
2010 IEEE 15th Conference on Emerging Technologies & Factory Automation (ETFA 2010), 2010The need for monitoring underwater sensors, communications between submarines or sonar, makes underwater acoustic communications an important field of research. Electromagnetic waves are quickly attenuated in this medium and thus acoustic waves are the best option for communications.
Joaquín Aparicio +5 more
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Channel simulation for underwater acoustic communication network
Proceedings of the Seventh ACM International Conference on Underwater Networks and Systems - WUWNet '12, 2012Significant advancements in underwater acoustic communication have been achieved in recent decades. In the dynamic ocean environment, various physical processes can significantly affect the communication channel. The time-varying underwater channel has both deterministic and stochastic features. Due to the dynamic environment and the complex properties
Aijun Song, Mohsen Badiey
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