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Possenti, Luca (author), de Nooijer, Lennart (author), de Jong, Christ (author), Lam, Frans Peter (author), Beelen, Simon (author), Bosschers, Johan (author), van Terwisga, T.J.C. (author), Stigter, Marinus (author), Reichart, Gert Jan (author)Since the industrial revolution the ocean has become noisier. The global increase in shipping is one of the main contributors to this. In some regions, shipping contributed to an increase in ambient noise of several decibels, especially at low frequencies (10 to 100 Hz). Such an increase can have a substantial negative impact on fish,...review 2024
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Wang, Yujie (author), Zhang, Qunfei (author), Ma, Shengqian (author), Zhang, Lingling (author), Han, Jing (author), Leus, G.J.T. (author)Differential orthogonal signal-division multiplexing (OSDM) is attractive for underwater acoustic (UWA) communications because it can eliminate channel estimation, resulting in a substantial reduction of complexity at the receiver. However, when the channel is time-varying, it may suffer from serious inter-vector interference (IVI), which is...conference paper 2023
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van Heteren, Mauries (author)The underwater acoustic environment is amongst the most challenging mediums for wireless communications. The three distinct challenges of underwater acoustic communication are the low and nonuniform propagation speed, frequency-dependent attenuation and time-varying multipath propagation.<br/>To cope with these challenges, physical layer...master thesis 2022
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van de Voort, Nick (author)Remotely Operated Vehicles (ROVs) are positioned relative to an underwater acoustic positioning system: Ultra-Short BaseLine (USBL). The accuracy is affected by refraction artifacts, caused by the variations of the sound velocity in the water column. Accurate positioning would require continuous measuring of the sound velocity profile (SVP)...master thesis 2022
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Han, Jing (author), Chepuri, Sundeep Prabhakar (author), Leus, G.J.T. (author)Orthogonal signal-division multiplexing (OSDM) has recently emerged as a promising modulation scheme for underwater acoustic communications. Although providing more flexibility in system design, it suffers from a special interference structure over time-varying channels. To enable reliable OSDM equalization, we propose a joint channel impulse...journal article 2020
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Han, Jing (author), Ma, Shengqian (author), Wang, Yujie (author), Leus, G.J.T. (author)Orthogonal signal-division multiplexing (OSDM) is an attractive alternative to conventional orthogonal frequency-division multiplexing (OFDM) due to its enhanced ability in peak-to-average power ratio (PAPR) reduction. Combining OSDM with multiple-input multiple-output (MIMO) signaling has the potential to achieve high spectral and power...journal article 2020
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Han, Jing (author), Wang, Yujie (author), Gong, Zehui (author), Leus, G.J.T. (author)Orthogonal signal-division multiplexing (OSDM) has recently emerged as a promising alternative to orthogonal frequency division multiplexing (OFDM) for high-rate wireless communications. Although providing more flexibility in system design, it suffers from a special interference structure, namely inter-vector interference (IVI), when channel...journal article 2020
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Ebihara, Tadashi (author), Ogasawara, Hanako (author), Leus, G.J.T. (author)In this paper, we propose a novel underwater acoustic (UWA) communication scheme that achieves energy and spectrum efficiency simultaneously by combining Doppler-resilient orthogonal signal division multiplexing (D-OSDM) and multiple-input-multiple-output (MIMO) signaling. We present both the transmitter processing and the receiver processing...review 2020
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Han, J. (author), Chepuri, S.P. (author), Zhang, Qunfei (author), Leus, G.J.T. (author)Orthogonal signal-division multiplexing (OSDM) is a promising modulation scheme that provides a generalized framework to unify orthogonal frequency-division multiplexing (OFDM) and single-carrier frequency-domain equalization. By partitioning each data block into vectors, it allows for a flexible configuration to trade off resource management...journal article 2019
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Han, J. (author), Zhang, Lingling (author), Zhang, Qunfei (author), Leus, G.J.T. (author)Orthogonal signal-division multiplexing (OSDM) is a generalized modulation scheme to bridge the gap between orthogonal frequency-division multiplexing (OFDM) and single-carrier frequency-domain equalization. It allows significantly more flexibility in system design; however, over doubly-selective channels, it suffers from a special signal...journal article 2019
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Gaida, T.C. (author), Ali, Tengku Afrizal Tengku (author), Snellen, M. (author), Amiri Simkooei, A. (author), van Dijk, T.A.G.P. (author), Simons, D.G. (author)Multi-frequency backscatter data collected from multibeam echosounders (MBESs) is increasingly becoming available. The ability to collect data at multiple frequencies at the same time is expected to allow for better discrimination between seabed sediments. We propose an extension of the Bayesian method for seabed classification to multi...journal article 2018
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Kasteel, Elisabeth (author)This thesis investigates the important physical processes related to underwater sound propagation due to offshore pile driving with the first commercial and numerical model called the Underwater Acoustic Simulator (UAS). To make adequately use of noise mitigation measures during offshore wind projects and to protect marine life the prediction of...master thesis 2018
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Ebihara, T. (author), Leus, G.J.T. (author), Ogasawara, Hanako (author)Underwater acoustic (UWA) channels are one of the historical mobile ultrawideband channels characterized by large delay and Doppler spreads, but reliable UWA communication remains challenging. Here we performed an initial demonstration of the Doppler-resilient orthogonal signal division multiplexing (D-OSDM) technique in an actual sea...journal article 2018
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Ebihara, Tadashi (author), Leus, G.J.T. (author), Ogasawara, Hanako (author)In this paper, we propose a novel underwater acoustic communication scheme that achieves energy and spectrum efficiency simultaneously by combining Doppler-resilient orthogonal signal division multiplexing (D-OSDM) and multiple-input multiple-output (MIMO) signaling. We present both the transmitter and receiver processing for MIMO D-OSDM. We...conference paper 2018
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Gaida, T.C. (author), Snellen, M. (author), van Dijk, Thaiënne A.G.P. (author), Simons, D.G. (author)Extensive seabed sediment mapping is highly relevant to describe marine ecosystems and to quantify the distribution and extent of benthic habitats. Compared to traditional mapping methods, primarily based on bed sampling, multibeam echo sounding (MBES) is a time-efficient tool to acquire high-resolution bathymetric and backscatter data over...journal article 2018
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Han, J. (author), Zhang, Lingling (author), Zhang, Qunfei (author), Leus, G.J.T. (author)Differential orthogonal frequency division multiplexing (OFDM) is practically attractive for underwater acoustic communications since it has the potential to obviate channel estimation. However, similar to coherent OFDM, it may suffer from severe inter-carrier interference over time-varying channels. To alleviate the induced performance...journal article 2018
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Peng, Yaxi (author)Anthropogenic underwater noise generated by pile driving has been an issue of serious concern<br/>for a long period of time. The underwater noise pollution from pile driving could pose a threat<br/>to marine mammals. To reduce the low-frequency noise, many offshore companies develop<br/>various treatments and alternatives for pile driving. In...master thesis 2017
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Ebihara, T. (author), Leus, G.J.T. (author)Underwater acoustic (UWA) channels are characterized by a severe spread in time and frequency, and are usually labeled as “doubly spread channels.” In this paper, we propose Doppler-resilient orthogonal signal-division multiplexing (D-OSDM), to provide a highly reliable communication environment in doubly spread channels for UWA communication. D...journal article 2015
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Ramezani, H. (author), Leus, G. (author)In this paper, we analyze the problem of acoustic ranging between sensor nodes in an underwater environment. The underwater medium is assumed to be composed of multiple isogradient sound speed profile (SSP) layers where in each layer the sound speed is linearly related to the depth. Furthermore, each sensor node is able to measure its depth and...journal article 2012
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Simons, D.G. (author), Snellen, M. (author), Ainslie, M.A. (author)Sound backscattered from the seabed has been measured in a 10x10-nmi2 region of the North Sea, characterized by a variety of bottom types, including mud, sand, and gravel. The backscattering strength measurements are made by a forward- looking sonar, operating at 100 kHz and tilted at an angle of 30 from the horizontal. Fifty bottom-grab samples...journal article 2007
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