Pub Date : 2015-10-22DOI: 10.23919/OCEANS.2015.7404585
R. Raulefs, Wei Wang, A. Rodriguez, A. Dammann
Maritime communication currently changes from analog to digital in the VHF band. The limited bandwidth of 100 kHz in the VHF band results in low data rates of a maximum of 100 kbit/s in a region of several of to 70 kilometers. Alternative solutions could be the access to 3G or 4G cellular communication systems which offer data rates of up to tens of megabits. However, these access schemes are designed for a very limited coverage of several hundreds of meters for mobile users and are seldom available on the sea. Therefore, in the ITS band at 5, 85 GHz a broadband channel of 20 MHz is defined for maritime applications. In this paper we analyze the communication capacity depending on the different antenna heights and different distances between transmitter and receiver.
{"title":"Capacity analysis for broadband communications on sea","authors":"R. Raulefs, Wei Wang, A. Rodriguez, A. Dammann","doi":"10.23919/OCEANS.2015.7404585","DOIUrl":"https://doi.org/10.23919/OCEANS.2015.7404585","url":null,"abstract":"Maritime communication currently changes from analog to digital in the VHF band. The limited bandwidth of 100 kHz in the VHF band results in low data rates of a maximum of 100 kbit/s in a region of several of to 70 kilometers. Alternative solutions could be the access to 3G or 4G cellular communication systems which offer data rates of up to tens of megabits. However, these access schemes are designed for a very limited coverage of several hundreds of meters for mobile users and are seldom available on the sea. Therefore, in the ITS band at 5, 85 GHz a broadband channel of 20 MHz is defined for maritime applications. In this paper we analyze the communication capacity depending on the different antenna heights and different distances between transmitter and receiver.","PeriodicalId":403976,"journal":{"name":"OCEANS 2015 - MTS/IEEE Washington","volume":"9 8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121677341","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-10-22DOI: 10.23919/OCEANS.2015.7404477
E. Creed, W. Ross, R. Lueck, Peter Stern, W. Douglas, F. Wolk, R. Hall
Seagliders are a type of propeller-less AUV that glide through the water by changing their buoyancy. They have become mainstream collectors of standard oceanographic data (conductivity, temperature, pressure, dissolved oxygen, fluorescence and backscatter) and are increasingly used as trucks to carry a wide variety of hydrographic and bio-geochemical sensors. The extended sensor capability enhances the utility of the gliders for oceanographic observations. Seagliders are designed and optimized for long-term missions (up to 10 months) and deep sea profiling (up to 1000 m). They provide high resolution oceanographic data with very good temporal and spatial density, in near real-time, at a fraction of the cost of ship collected data. These performance parameters are sometimes at odds with the physical dimensions and electrical requirements of the hydrographic and bio-geochemical sensors scientists want installed in gliders. However, as the acceptance of gliders as an integral component of the oceanographic suite of measurement tools grows so do the efforts of sensor vendors to develop products that meet the size, weight and power requirements for successful glider integration. Turbulence microstructure sensors are one measurement system that scientists desired on Seagliders but that until recently did not fit the glider footprint. In collaboration with Rockland Scientific, Inc., a suite of RSI turbulence microstructure sensors was recently integrated into a Seaglider and the system's performance validated during field tests in Puget Sound near Seattle, WA and in Loch Linnhe on the west coast of Scotland. Ocean turbulence controls the mixing of water masses, biogeochemical fluxes within them, and facilitates ocean-atmosphere gas exchange. As a result, turbulence impacts global ocean circulation, polar ice melt rates, drawdown of atmospheric carbon dioxide and carbon deposition, coastal and deep ocean ecology, commercial fisheries, and the dispersion of pollutants. Turbulent mixing is also recognized as a key parameter in global climate models, used for understanding and predicting future climate change. Seagliders equipped with turbulence microstructure sensors will allow scientists to map the geographical distribution and temporal variability of mixing in the ocean on scales not possible with ship-based measurements. This presentation discusses the technical aspects of the integration of the turbulence sensor suite on a Seaglider with an emphasis on achieving high data quality, while retaining the performance characteristics of the Seaglider. We will also describe applications for this sensor suite, examine the turbulence measurement data already collected by the Seaglider and discuss future deployment plans.
{"title":"Integration of a RSI microstructure sensing package into a Seaglider","authors":"E. Creed, W. Ross, R. Lueck, Peter Stern, W. Douglas, F. Wolk, R. Hall","doi":"10.23919/OCEANS.2015.7404477","DOIUrl":"https://doi.org/10.23919/OCEANS.2015.7404477","url":null,"abstract":"Seagliders are a type of propeller-less AUV that glide through the water by changing their buoyancy. They have become mainstream collectors of standard oceanographic data (conductivity, temperature, pressure, dissolved oxygen, fluorescence and backscatter) and are increasingly used as trucks to carry a wide variety of hydrographic and bio-geochemical sensors. The extended sensor capability enhances the utility of the gliders for oceanographic observations. Seagliders are designed and optimized for long-term missions (up to 10 months) and deep sea profiling (up to 1000 m). They provide high resolution oceanographic data with very good temporal and spatial density, in near real-time, at a fraction of the cost of ship collected data. These performance parameters are sometimes at odds with the physical dimensions and electrical requirements of the hydrographic and bio-geochemical sensors scientists want installed in gliders. However, as the acceptance of gliders as an integral component of the oceanographic suite of measurement tools grows so do the efforts of sensor vendors to develop products that meet the size, weight and power requirements for successful glider integration. Turbulence microstructure sensors are one measurement system that scientists desired on Seagliders but that until recently did not fit the glider footprint. In collaboration with Rockland Scientific, Inc., a suite of RSI turbulence microstructure sensors was recently integrated into a Seaglider and the system's performance validated during field tests in Puget Sound near Seattle, WA and in Loch Linnhe on the west coast of Scotland. Ocean turbulence controls the mixing of water masses, biogeochemical fluxes within them, and facilitates ocean-atmosphere gas exchange. As a result, turbulence impacts global ocean circulation, polar ice melt rates, drawdown of atmospheric carbon dioxide and carbon deposition, coastal and deep ocean ecology, commercial fisheries, and the dispersion of pollutants. Turbulent mixing is also recognized as a key parameter in global climate models, used for understanding and predicting future climate change. Seagliders equipped with turbulence microstructure sensors will allow scientists to map the geographical distribution and temporal variability of mixing in the ocean on scales not possible with ship-based measurements. This presentation discusses the technical aspects of the integration of the turbulence sensor suite on a Seaglider with an emphasis on achieving high data quality, while retaining the performance characteristics of the Seaglider. We will also describe applications for this sensor suite, examine the turbulence measurement data already collected by the Seaglider and discuss future deployment plans.","PeriodicalId":403976,"journal":{"name":"OCEANS 2015 - MTS/IEEE Washington","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117269046","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-10-19DOI: 10.23919/OCEANS.2015.7404431
M. Hammond, Ashley Clark, A. Mahajan, Sumant Sharma, S. Rock
An algorithm for automating correspondence detection between point clouds composed of multibeam sonar data is presented. This allows accurate initialization for point cloud alignment techniques even in cases where accurate inertial navigation is not available, such as iceberg profiling or vehicles with low-grade inertial navigation systems. Techniques from computer vision literature are used to extract, label, and match keypoints between “pseudo-images” generated from these point clouds. Image matches are refined using RANSAC and information about the vehicle trajectory. The resulting correspondences can be used to initialize an iterative closest point (ICP) registration algorithm to estimate accumulated navigation error and aid in the creation of accurate, self-consistent maps. The results presented use multibeam sonar data obtained from multiple overlapping passes of an underwater canyon in Monterey Bay, California. Using strict matching criteria, the method detects 23 between-swath correspondence events in a set of 155 pseudo-images with zero false positives. Using less conservative matching criteria doubles the number of matches but introduces several false positive matches as well. Heuristics based on known vehicle trajectory information are used to eliminate these.
{"title":"Automated point cloud correspondence detection for underwater mapping using AUVs","authors":"M. Hammond, Ashley Clark, A. Mahajan, Sumant Sharma, S. Rock","doi":"10.23919/OCEANS.2015.7404431","DOIUrl":"https://doi.org/10.23919/OCEANS.2015.7404431","url":null,"abstract":"An algorithm for automating correspondence detection between point clouds composed of multibeam sonar data is presented. This allows accurate initialization for point cloud alignment techniques even in cases where accurate inertial navigation is not available, such as iceberg profiling or vehicles with low-grade inertial navigation systems. Techniques from computer vision literature are used to extract, label, and match keypoints between “pseudo-images” generated from these point clouds. Image matches are refined using RANSAC and information about the vehicle trajectory. The resulting correspondences can be used to initialize an iterative closest point (ICP) registration algorithm to estimate accumulated navigation error and aid in the creation of accurate, self-consistent maps. The results presented use multibeam sonar data obtained from multiple overlapping passes of an underwater canyon in Monterey Bay, California. Using strict matching criteria, the method detects 23 between-swath correspondence events in a set of 155 pseudo-images with zero false positives. Using less conservative matching criteria doubles the number of matches but introduces several false positive matches as well. Heuristics based on known vehicle trajectory information are used to eliminate these.","PeriodicalId":403976,"journal":{"name":"OCEANS 2015 - MTS/IEEE Washington","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122054828","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-10-19DOI: 10.23919/OCEANS.2015.7401942
Cindy Bernard, C. Ioana, I. Orović, S. Stankovic
Natural signals are often characterized by nonlinear timefrequency structures and more especially in underwater context. Underwater mammal vocalizations or dispersive phenomena are just some examples of contexts where nonlinear time-frequency structures of signal's components exist. Their is of great importance for detection and classification purposes but also for phenomenon characterization. In this work, starting from the concept of warping-based time-frequency analysis, we propose a new analysis method that combines the properties of the waping transform with the concept of compressive sensing. It provides a more accurate characterization of nonlinear time-frequency structures in terms of the estimation of their parameters. Results provided for simulated data prove the interst of this new approach with respect to the spectrogram-based method.
{"title":"Analysis of underwater signals with nonlinear time-frequency structures using warping-based compressive sensing algorithm","authors":"Cindy Bernard, C. Ioana, I. Orović, S. Stankovic","doi":"10.23919/OCEANS.2015.7401942","DOIUrl":"https://doi.org/10.23919/OCEANS.2015.7401942","url":null,"abstract":"Natural signals are often characterized by nonlinear timefrequency structures and more especially in underwater context. Underwater mammal vocalizations or dispersive phenomena are just some examples of contexts where nonlinear time-frequency structures of signal's components exist. Their is of great importance for detection and classification purposes but also for phenomenon characterization. In this work, starting from the concept of warping-based time-frequency analysis, we propose a new analysis method that combines the properties of the waping transform with the concept of compressive sensing. It provides a more accurate characterization of nonlinear time-frequency structures in terms of the estimation of their parameters. Results provided for simulated data prove the interst of this new approach with respect to the spectrogram-based method.","PeriodicalId":403976,"journal":{"name":"OCEANS 2015 - MTS/IEEE Washington","volume":"701 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123691854","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-10-19DOI: 10.23919/OCEANS.2015.7401841
Clément Iphar, A. Napoli, C. Ray
The Automatic Identification System (AIS) was initially designed for safety and security of navigation purposes. However it was progressively also used for other objectives, such as surveillance, and thus led to the discovery of behaviors such as the falsification of the AIS messages by people that have been carrying out illegal activities and will to keep their activities up in an hidden way. In addition, the messages contain erroneous data and undergo spoofing attacks. The paper introduces the quality dimensions of data that shall be used in a quality assessment of AIS messages, in order to point out the dubious ones. The principles of a methodological approach for the detection of such data errors and falsifications are introduced.
{"title":"Detection of false AIS messages for the improvement of maritime situational awareness","authors":"Clément Iphar, A. Napoli, C. Ray","doi":"10.23919/OCEANS.2015.7401841","DOIUrl":"https://doi.org/10.23919/OCEANS.2015.7401841","url":null,"abstract":"The Automatic Identification System (AIS) was initially designed for safety and security of navigation purposes. However it was progressively also used for other objectives, such as surveillance, and thus led to the discovery of behaviors such as the falsification of the AIS messages by people that have been carrying out illegal activities and will to keep their activities up in an hidden way. In addition, the messages contain erroneous data and undergo spoofing attacks. The paper introduces the quality dimensions of data that shall be used in a quality assessment of AIS messages, in order to point out the dubious ones. The principles of a methodological approach for the detection of such data errors and falsifications are introduced.","PeriodicalId":403976,"journal":{"name":"OCEANS 2015 - MTS/IEEE Washington","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114670103","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-10-19DOI: 10.23919/OCEANS.2015.7404414
M. Tanguy, A. Napoli
The globalization of trade is due to the transportation possibilities and the standardization (containerization of freight). The dependency of the economy to the sea and to the merchant navy has increase this last decade. This process forms a worldwide maritime network between the different locations of production and consumption. This network, representing between 80 % and 90% of world traffic is a major economic concern, including freight distribution, raw materials or energy. Rodrigue demonstrates[1] the economic dependency of energy is increasing in the industrialized countries (North America, Europe, East Asia). The inter-regional trade of oil was 31 million bbl/day in 2002 and is expected to grow up to 57 bbl/day in 2030 [2]. Most of the international traffic use a maritime way, where may occur disruptions. For example, the Suez crisis (1956-1957) caused a closure of the canal, reducing the throughput capacity of transportation. This disruption cost a 2 millions of barrels lost per day. This article focuses on vulnerability of the energy supply, and proposes a methodology to formalize and assess the vulnerability of the network by taking into account the spatial structure of maritime territories.
{"title":"A methodology to improve the assessment of vulnerability on the maritime supply chain of energy","authors":"M. Tanguy, A. Napoli","doi":"10.23919/OCEANS.2015.7404414","DOIUrl":"https://doi.org/10.23919/OCEANS.2015.7404414","url":null,"abstract":"The globalization of trade is due to the transportation possibilities and the standardization (containerization of freight). The dependency of the economy to the sea and to the merchant navy has increase this last decade. This process forms a worldwide maritime network between the different locations of production and consumption. This network, representing between 80 % and 90% of world traffic is a major economic concern, including freight distribution, raw materials or energy. Rodrigue demonstrates[1] the economic dependency of energy is increasing in the industrialized countries (North America, Europe, East Asia). The inter-regional trade of oil was 31 million bbl/day in 2002 and is expected to grow up to 57 bbl/day in 2030 [2]. Most of the international traffic use a maritime way, where may occur disruptions. For example, the Suez crisis (1956-1957) caused a closure of the canal, reducing the throughput capacity of transportation. This disruption cost a 2 millions of barrels lost per day. This article focuses on vulnerability of the energy supply, and proposes a methodology to formalize and assess the vulnerability of the network by taking into account the spatial structure of maritime territories.","PeriodicalId":403976,"journal":{"name":"OCEANS 2015 - MTS/IEEE Washington","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114529924","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-10-19DOI: 10.23919/OCEANS.2015.7404419
Gabriel Vasile, G. D'Urso, Eric de Oliveira, J. Guillet, Elena Lungu
This paper introduces the concept of automatic reference selection for active ultrasound wild salmon monitoring systems in turbulent underwater environments. A general in situ calibration procedure is proposed which allows grate improvements in terms of fish detection, identification and tracking capabilities.
{"title":"Reference selection for an active ultrasound wild salmon monitoring system","authors":"Gabriel Vasile, G. D'Urso, Eric de Oliveira, J. Guillet, Elena Lungu","doi":"10.23919/OCEANS.2015.7404419","DOIUrl":"https://doi.org/10.23919/OCEANS.2015.7404419","url":null,"abstract":"This paper introduces the concept of automatic reference selection for active ultrasound wild salmon monitoring systems in turbulent underwater environments. A general in situ calibration procedure is proposed which allows grate improvements in terms of fish detection, identification and tracking capabilities.","PeriodicalId":403976,"journal":{"name":"OCEANS 2015 - MTS/IEEE Washington","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126365400","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-10-19DOI: 10.23919/OCEANS.2015.7404420
Gabriel Vasile, G. D'Urso, R. Charlatchka, Elena Lungu
This paper introduces the concept of coupling ultrasound transducers with piezoelectric accelerometers for active ultrasound bedload monitoring in underwater environments. A general system calibration procedure is proposed which allows the enduser to establish a real-time link between the energy of the received signals and the bedload transport phenomena.
{"title":"Calibration of an active ultrasound bedload monitoring system for underwater environments","authors":"Gabriel Vasile, G. D'Urso, R. Charlatchka, Elena Lungu","doi":"10.23919/OCEANS.2015.7404420","DOIUrl":"https://doi.org/10.23919/OCEANS.2015.7404420","url":null,"abstract":"This paper introduces the concept of coupling ultrasound transducers with piezoelectric accelerometers for active ultrasound bedload monitoring in underwater environments. A general system calibration procedure is proposed which allows the enduser to establish a real-time link between the energy of the received signals and the bedload transport phenomena.","PeriodicalId":403976,"journal":{"name":"OCEANS 2015 - MTS/IEEE Washington","volume":"81 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132962978","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-10-19DOI: 10.23919/OCEANS.2015.7401934
You Li, M. Rendas
The paper proposes rCV, a new randomised Cross Validation (CV) criterion specially designed for use with data acquired over non-uniformly scattered designs, like the linear transect surveys typical in environmental observation. The new criterion enables a robust parameterisation of interpolation algorithms, in a manner completely driven by the data and free of any modelling assumptions. The new CV method randomly chooses the hold-out sets such that they reflect, statistically, the geometry of the design with respect to the unobserved points of the area where the observations are to be extrapolated, minimising biases due to the particular geometry of the designs. Numerical results on both simulated and realistic datasets show its robustness and superiority, leading to interpolated fields with smaller error.
{"title":"Tuning interpolation methods for environmental uni-dimensional (transect) surveys","authors":"You Li, M. Rendas","doi":"10.23919/OCEANS.2015.7401934","DOIUrl":"https://doi.org/10.23919/OCEANS.2015.7401934","url":null,"abstract":"The paper proposes rCV, a new randomised Cross Validation (CV) criterion specially designed for use with data acquired over non-uniformly scattered designs, like the linear transect surveys typical in environmental observation. The new criterion enables a robust parameterisation of interpolation algorithms, in a manner completely driven by the data and free of any modelling assumptions. The new CV method randomly chooses the hold-out sets such that they reflect, statistically, the geometry of the design with respect to the unobserved points of the area where the observations are to be extrapolated, minimising biases due to the particular geometry of the designs. Numerical results on both simulated and realistic datasets show its robustness and superiority, leading to interpolated fields with smaller error.","PeriodicalId":403976,"journal":{"name":"OCEANS 2015 - MTS/IEEE Washington","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127310065","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-10-18DOI: 10.23919/OCEANS.2015.7404593
R. Raulefs, T. A. Stenbock, A. Dammann, S. Plass
Enhancing diversity techniques allow long time code bit interleavers with strong channel codes to offer enough margin to cope with a satellite system in parallel. However, for channel codes which need to cope with voice applications a much shorter delay has to be considered. Therefore, artificially enhancing diversity techniques could resolve this even voice communication links. VDES could then also serve as a joint data and voice communication service. We further investigated the PAPR of singleand multicarrier systems. The impact of the roll-off factor showed about 1.5 worse PAPR compared to a multi-carrier system with only eight subcarriers. The loss could be partially compensated by techniques that shape the signal before the power amplifier to optimize the communication link.
{"title":"Physical layer design towards VHF Data Exchange (VDE) Link","authors":"R. Raulefs, T. A. Stenbock, A. Dammann, S. Plass","doi":"10.23919/OCEANS.2015.7404593","DOIUrl":"https://doi.org/10.23919/OCEANS.2015.7404593","url":null,"abstract":"Enhancing diversity techniques allow long time code bit interleavers with strong channel codes to offer enough margin to cope with a satellite system in parallel. However, for channel codes which need to cope with voice applications a much shorter delay has to be considered. Therefore, artificially enhancing diversity techniques could resolve this even voice communication links. VDES could then also serve as a joint data and voice communication service. We further investigated the PAPR of singleand multicarrier systems. The impact of the roll-off factor showed about 1.5 worse PAPR compared to a multi-carrier system with only eight subcarriers. The loss could be partially compensated by techniques that shape the signal before the power amplifier to optimize the communication link.","PeriodicalId":403976,"journal":{"name":"OCEANS 2015 - MTS/IEEE Washington","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133108188","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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