Pub Date : 2001-11-05DOI: 10.1109/OCEANS.2001.968279
J. M. Welch
The National Ocean Service (NOS) Center for Operational Oceanographic Products and Services (CO-OPS) manages the NOS Real-Time Monitoring Infrastructure. CO-OPS provides the national infrastructure, science, and technical expertise to monitor, assess, and disseminate coastal oceanographic products and services necessary to support NOAA's dual mission of environmental stewardship and environmental assessment and prediction. CO-OPS strengthens core capabilities through additional partnership links with outside groups including private organizations. A CO-OPS operating principle is to focus the core workforce capability on the establishment and maintenance of NOS program and technical standards, validation and certification of data and information products, research and development, and quality control/assurance (QA/QC) of data and information products. Validation, certification, and QA/QC all link to the liability associated with CO-OPS data, information products, and services.
{"title":"National Ocean Service Real-Time Monitoring Infrastructure. Working for America's coasts","authors":"J. M. Welch","doi":"10.1109/OCEANS.2001.968279","DOIUrl":"https://doi.org/10.1109/OCEANS.2001.968279","url":null,"abstract":"The National Ocean Service (NOS) Center for Operational Oceanographic Products and Services (CO-OPS) manages the NOS Real-Time Monitoring Infrastructure. CO-OPS provides the national infrastructure, science, and technical expertise to monitor, assess, and disseminate coastal oceanographic products and services necessary to support NOAA's dual mission of environmental stewardship and environmental assessment and prediction. CO-OPS strengthens core capabilities through additional partnership links with outside groups including private organizations. A CO-OPS operating principle is to focus the core workforce capability on the establishment and maintenance of NOS program and technical standards, validation and certification of data and information products, research and development, and quality control/assurance (QA/QC) of data and information products. Validation, certification, and QA/QC all link to the liability associated with CO-OPS data, information products, and services.","PeriodicalId":326183,"journal":{"name":"MTS/IEEE Oceans 2001. An Ocean Odyssey. Conference Proceedings (IEEE Cat. No.01CH37295)","volume":"131 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121057965","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 : 2001-11-05DOI: 10.1109/OCEANS.2001.968230
A. Orlov
Natural anomalies of fish eyes are noted occasionally and were never previously reported for snailfishes (Liparidae). Among fishes melanism is occurred in the nature relatively rare and sometimes associated with intergeneric hybridization or pathologic invasion. Until now the cases of melanism among fishes were known only for some paddlefishes (Polyodontidae), gars (Lepidosteidae), herrings (Clupeidae), livebearers (Poeciliidae), carps (Cyprinidae), loaches (Cobitiidae), salmons (Salmonidae), cods (Gadidae), rockfishes (Scorpaenidae), and righteye flounders (Pleuronectidae). Melanistic specimens of snailfishes were never previously reported. The first records of single-eyed specimen of round snailfish, Careproctus roseofuscus, and melanistic specimens of dimdisc snailfish, Elassodiscus tremebundus, and undescribed species, Careproctus cf. cyclocephalus, are documented. Some external characters of single-eyed and melanistic specimens are given and their photographs are provided.
{"title":"Rare events of cyclopia and melanism among deep-water snailfishes (Liparidae, Scorpaeniformes)","authors":"A. Orlov","doi":"10.1109/OCEANS.2001.968230","DOIUrl":"https://doi.org/10.1109/OCEANS.2001.968230","url":null,"abstract":"Natural anomalies of fish eyes are noted occasionally and were never previously reported for snailfishes (Liparidae). Among fishes melanism is occurred in the nature relatively rare and sometimes associated with intergeneric hybridization or pathologic invasion. Until now the cases of melanism among fishes were known only for some paddlefishes (Polyodontidae), gars (Lepidosteidae), herrings (Clupeidae), livebearers (Poeciliidae), carps (Cyprinidae), loaches (Cobitiidae), salmons (Salmonidae), cods (Gadidae), rockfishes (Scorpaenidae), and righteye flounders (Pleuronectidae). Melanistic specimens of snailfishes were never previously reported. The first records of single-eyed specimen of round snailfish, Careproctus roseofuscus, and melanistic specimens of dimdisc snailfish, Elassodiscus tremebundus, and undescribed species, Careproctus cf. cyclocephalus, are documented. Some external characters of single-eyed and melanistic specimens are given and their photographs are provided.","PeriodicalId":326183,"journal":{"name":"MTS/IEEE Oceans 2001. An Ocean Odyssey. Conference Proceedings (IEEE Cat. No.01CH37295)","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122852928","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 : 2001-11-05DOI: 10.1109/OCEANS.2001.968149
R. Livingston
A 13-year field analysis of the Perdido Bay system (Gulf of Mexico) indicated that orthophosphate and ammonia loading from a pulp mill was associated with a series of plankton blooms. Bloom species (10) followed distinct seasonal and interannual trends that included the replacement of initial diatom blooms by raphidophytes and dinoflagellates. Long-term habitat changes associated with river flow rates (drought/flood cycles) defined varying susceptibility to bloom development. The initiation and proliferation of plankton blooms were also affected by seasonal changes of temperature, phosphorus and nitrogen loading, and associated nutrient concentration gradients. Plankton blooms were associated with deterioration of secondary production through food web interactions. The bivalve Rangia cuneata was an indicator of such effects. Most scientific efforts continue to overlook the world-wide impacts of anthropogenous nutrient loading and associated plankton blooms due to the lack of long-term analyses of species-specific, community-level phytoplankton assemblages and the replacement of ecosystem studies with patch-quilt ecological efforts that depend on disorganized and inadequate data acquisition and uncoordinated multidisciplinary efforts.
{"title":"Nutrient loading and coastal plankton blooms: seasonal/interannual successions and effects on secondary production","authors":"R. Livingston","doi":"10.1109/OCEANS.2001.968149","DOIUrl":"https://doi.org/10.1109/OCEANS.2001.968149","url":null,"abstract":"A 13-year field analysis of the Perdido Bay system (Gulf of Mexico) indicated that orthophosphate and ammonia loading from a pulp mill was associated with a series of plankton blooms. Bloom species (10) followed distinct seasonal and interannual trends that included the replacement of initial diatom blooms by raphidophytes and dinoflagellates. Long-term habitat changes associated with river flow rates (drought/flood cycles) defined varying susceptibility to bloom development. The initiation and proliferation of plankton blooms were also affected by seasonal changes of temperature, phosphorus and nitrogen loading, and associated nutrient concentration gradients. Plankton blooms were associated with deterioration of secondary production through food web interactions. The bivalve Rangia cuneata was an indicator of such effects. Most scientific efforts continue to overlook the world-wide impacts of anthropogenous nutrient loading and associated plankton blooms due to the lack of long-term analyses of species-specific, community-level phytoplankton assemblages and the replacement of ecosystem studies with patch-quilt ecological efforts that depend on disorganized and inadequate data acquisition and uncoordinated multidisciplinary efforts.","PeriodicalId":326183,"journal":{"name":"MTS/IEEE Oceans 2001. An Ocean Odyssey. Conference Proceedings (IEEE Cat. No.01CH37295)","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124301882","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 : 2001-11-05DOI: 10.1109/OCEANS.2001.968696
R. Stokey, T. Austin, B. Allen, N. Forrester, E. Gifford, R. Goldsborough, G. Packard, M. Purcell, C. von Alt
For several years, the engineers of the Oceanographic Systems Laboratory have been developing a version of the REMUS autonomous underwater vehicle (AUV) equipped with a Marine Sonics, Ltd. sidescan sonar. A sidescan equipped AUV allows operators to maintain a safe standoff distance from a potential minefield, and when equipped with other instrumentation provides high resolution hydrographic data as well. This paper provides a general discussion of sidescan search strategies as pertains to mine-hunting. It also describes the hardware and software interface from the vehicle and user interface to the sidescan system that allows pre-launch performance verification, and rapid post mission data analysis and exporting. results of this test are discussed and explained, including a variety of performance metrics. A practical example is provided. During August of 2000, the REMUS system participated in the US Navy exercise, "Fleet Battle Experiment-Hotel" and generated a high resolution map of a minefield covering over 3 square kilometers. The results of this test are discussed and explained, including a variety of performance metrics.
{"title":"Very shallow water mine countermeasures using the REMUS AUV: a practical approach yielding accurate results","authors":"R. Stokey, T. Austin, B. Allen, N. Forrester, E. Gifford, R. Goldsborough, G. Packard, M. Purcell, C. von Alt","doi":"10.1109/OCEANS.2001.968696","DOIUrl":"https://doi.org/10.1109/OCEANS.2001.968696","url":null,"abstract":"For several years, the engineers of the Oceanographic Systems Laboratory have been developing a version of the REMUS autonomous underwater vehicle (AUV) equipped with a Marine Sonics, Ltd. sidescan sonar. A sidescan equipped AUV allows operators to maintain a safe standoff distance from a potential minefield, and when equipped with other instrumentation provides high resolution hydrographic data as well. This paper provides a general discussion of sidescan search strategies as pertains to mine-hunting. It also describes the hardware and software interface from the vehicle and user interface to the sidescan system that allows pre-launch performance verification, and rapid post mission data analysis and exporting. results of this test are discussed and explained, including a variety of performance metrics. A practical example is provided. During August of 2000, the REMUS system participated in the US Navy exercise, \"Fleet Battle Experiment-Hotel\" and generated a high resolution map of a minefield covering over 3 square kilometers. The results of this test are discussed and explained, including a variety of performance metrics.","PeriodicalId":326183,"journal":{"name":"MTS/IEEE Oceans 2001. An Ocean Odyssey. Conference Proceedings (IEEE Cat. No.01CH37295)","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125383275","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 : 2001-11-05DOI: 10.1109/OCEANS.2001.968288
S. Sebastian, J. Caruthers
The acoustic effects of bubbles can have a major impact on hydrographic operations using multibeam sonars and on the quality of the data they produce. It is well-known that bubble sweepdown, bubbles entrained beneath the hull due to high ship speeds or heavy weather, is a significant problem, and means to mitigate the effects are sought. The bubble problem discussed in this paper has a different source - one which hydrographers have not yet taken into account. The bubbles that cause this problem are those naturally occurring in the sea. Natural bubbles exist in the ocean due to many causes such as breaking waves, rip currents carrying bubbles produced in surf zones out into deeper waters, impact of rain drops, swim bladders of sea life, and gas hydrates bubbling up from the seafloor. This paper discusses the characteristics of bubbles caused by breaking wind waves and rip currents and their effects on multibeam-sonar operations.
{"title":"Effects of naturally occurring bubbles on multibeam sonar operations","authors":"S. Sebastian, J. Caruthers","doi":"10.1109/OCEANS.2001.968288","DOIUrl":"https://doi.org/10.1109/OCEANS.2001.968288","url":null,"abstract":"The acoustic effects of bubbles can have a major impact on hydrographic operations using multibeam sonars and on the quality of the data they produce. It is well-known that bubble sweepdown, bubbles entrained beneath the hull due to high ship speeds or heavy weather, is a significant problem, and means to mitigate the effects are sought. The bubble problem discussed in this paper has a different source - one which hydrographers have not yet taken into account. The bubbles that cause this problem are those naturally occurring in the sea. Natural bubbles exist in the ocean due to many causes such as breaking waves, rip currents carrying bubbles produced in surf zones out into deeper waters, impact of rain drops, swim bladders of sea life, and gas hydrates bubbling up from the seafloor. This paper discusses the characteristics of bubbles caused by breaking wind waves and rip currents and their effects on multibeam-sonar operations.","PeriodicalId":326183,"journal":{"name":"MTS/IEEE Oceans 2001. An Ocean Odyssey. Conference Proceedings (IEEE Cat. No.01CH37295)","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126104937","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 : 2001-11-05DOI: 10.1109/OCEANS.2001.968749
G. S. Sammelmann
Over the past several years COASTSYSTA has developed a sonar simulation for modeling sonar performance in very shallow water and the surf zone called PC SWAT (Personal Computer Shallow Water Acoustic Tool-set). The latest version of PC SWAT (7.0) is scheduled for release in September of 2001. It includes propagation in a 3-dimensional environment, a time-varying sea surface, a model for the evolution of bubble clouds in the surf zone, 3-dimensional targets, and coherent imaging capabilities. This article focuses on some of the new features that have been added to PC SWAT during FY 2001.
{"title":"Propagation and scattering in very shallow water","authors":"G. S. Sammelmann","doi":"10.1109/OCEANS.2001.968749","DOIUrl":"https://doi.org/10.1109/OCEANS.2001.968749","url":null,"abstract":"Over the past several years COASTSYSTA has developed a sonar simulation for modeling sonar performance in very shallow water and the surf zone called PC SWAT (Personal Computer Shallow Water Acoustic Tool-set). The latest version of PC SWAT (7.0) is scheduled for release in September of 2001. It includes propagation in a 3-dimensional environment, a time-varying sea surface, a model for the evolution of bubble clouds in the surf zone, 3-dimensional targets, and coherent imaging capabilities. This article focuses on some of the new features that have been added to PC SWAT during FY 2001.","PeriodicalId":326183,"journal":{"name":"MTS/IEEE Oceans 2001. An Ocean Odyssey. Conference Proceedings (IEEE Cat. No.01CH37295)","volume":"120 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126301226","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 : 2001-11-05DOI: 10.1109/OCEANS.2001.968340
A. Waldhorst, R. Weber, J. Bohme
We apply a special modulation format derived from offset quadri-phase shift keying (OQPSK) to digital transmission and propose a novel practical multichannel receiver architecture for its demodulation. The receiver is based on the standard adaptive decision feed-back equalizer (DFE) which is extended so that both its multichannel feed-forward section and the feedback section operate fractionally spaced. We therefore introduce a new decision rule that exploits the structural properties of this signal type and allows the adaptive filters to be updated twice per symbol. This also enables the receiver to operate in a completely self-recovering, or 'blind' manner. To compensate for Doppler effects, explicit non-data-aided timing recovery and decision-directed carrier recovery is performed. To demonstrate the performance of the proposed system, the receiver is applied to experimental data for acoustic communication in shallow water where the information signal is both emitted by a fixed and a moving source.
{"title":"A blind multichannel DFE receiver for precoded OQPSK signal transmission in shallow water","authors":"A. Waldhorst, R. Weber, J. Bohme","doi":"10.1109/OCEANS.2001.968340","DOIUrl":"https://doi.org/10.1109/OCEANS.2001.968340","url":null,"abstract":"We apply a special modulation format derived from offset quadri-phase shift keying (OQPSK) to digital transmission and propose a novel practical multichannel receiver architecture for its demodulation. The receiver is based on the standard adaptive decision feed-back equalizer (DFE) which is extended so that both its multichannel feed-forward section and the feedback section operate fractionally spaced. We therefore introduce a new decision rule that exploits the structural properties of this signal type and allows the adaptive filters to be updated twice per symbol. This also enables the receiver to operate in a completely self-recovering, or 'blind' manner. To compensate for Doppler effects, explicit non-data-aided timing recovery and decision-directed carrier recovery is performed. To demonstrate the performance of the proposed system, the receiver is applied to experimental data for acoustic communication in shallow water where the information signal is both emitted by a fixed and a moving source.","PeriodicalId":326183,"journal":{"name":"MTS/IEEE Oceans 2001. An Ocean Odyssey. Conference Proceedings (IEEE Cat. No.01CH37295)","volume":"11 suppl_2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125932362","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 : 2001-11-05DOI: 10.1109/OCEANS.2001.968400
H. Freese, D. Gever, R. Evans, B. Sperry, R. B. Greene, D.J. Fabozzi
During the past year the CEROS program has funded a project to implement a broadband "real time" signal processing and propagation modeling suite at the Maui Supercomputing Center (MSC) that could be run via a Web-based user interface described by Gever and Fabozzi (see Oceans 2001 Conference, 2001). This processing suite takes advantage of the parallel computational resources at MSC, specifically the IBM SP2 multinode processor as well as PC clusters currently being brought on board or developed at MSC and SAIC. Our processing suites are a logical application of such machines because of the highly parallel nature of our codes which can typically be decomposed by frequency, space, or time. Our typical problem for which we demonstrated a "real time" throughput was for a 30 element array, a search volume of 90 degrees in bearing, 0 km to 10 km in range, and 0 to 100 meters in depth. This was done for a 100 Hz signal bandwidth.
{"title":"\"Real time\" broadband adaptive matched field processing","authors":"H. Freese, D. Gever, R. Evans, B. Sperry, R. B. Greene, D.J. Fabozzi","doi":"10.1109/OCEANS.2001.968400","DOIUrl":"https://doi.org/10.1109/OCEANS.2001.968400","url":null,"abstract":"During the past year the CEROS program has funded a project to implement a broadband \"real time\" signal processing and propagation modeling suite at the Maui Supercomputing Center (MSC) that could be run via a Web-based user interface described by Gever and Fabozzi (see Oceans 2001 Conference, 2001). This processing suite takes advantage of the parallel computational resources at MSC, specifically the IBM SP2 multinode processor as well as PC clusters currently being brought on board or developed at MSC and SAIC. Our processing suites are a logical application of such machines because of the highly parallel nature of our codes which can typically be decomposed by frequency, space, or time. Our typical problem for which we demonstrated a \"real time\" throughput was for a 30 element array, a search volume of 90 degrees in bearing, 0 km to 10 km in range, and 0 to 100 meters in depth. This was done for a 100 Hz signal bandwidth.","PeriodicalId":326183,"journal":{"name":"MTS/IEEE Oceans 2001. An Ocean Odyssey. Conference Proceedings (IEEE Cat. No.01CH37295)","volume":"84 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129977311","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 : 2001-11-05DOI: 10.1109/OCEANS.2001.968660
J. Impagliazzo, M. Medeiros, S. Kay
A portable high-resolution sonar has been under development to provide Navy divers with acoustic imaging systems for mine reconnaissance. The first phase of development was completed in 2000 with the demonstration of a broadband, 6% sparse line array, imaging a simple target in the NUWC Acoustic Test Facility (ATF). Element locations for this array were computed based on a grid point optimization technique which minimized close-in sidelobes. The center frequency was 2 MHz with a 667 kHz bandwidth. A new sparse planar array, consisting of 121 1 mm/spl times/1 mm 2 MHz elements, has been fabricated, to provide 3-D acoustic images of underwater targets. This array was also designed using the grid point optimization technique.
{"title":"Imaging with a 2 MHz sparse broadband planar array","authors":"J. Impagliazzo, M. Medeiros, S. Kay","doi":"10.1109/OCEANS.2001.968660","DOIUrl":"https://doi.org/10.1109/OCEANS.2001.968660","url":null,"abstract":"A portable high-resolution sonar has been under development to provide Navy divers with acoustic imaging systems for mine reconnaissance. The first phase of development was completed in 2000 with the demonstration of a broadband, 6% sparse line array, imaging a simple target in the NUWC Acoustic Test Facility (ATF). Element locations for this array were computed based on a grid point optimization technique which minimized close-in sidelobes. The center frequency was 2 MHz with a 667 kHz bandwidth. A new sparse planar array, consisting of 121 1 mm/spl times/1 mm 2 MHz elements, has been fabricated, to provide 3-D acoustic images of underwater targets. This array was also designed using the grid point optimization technique.","PeriodicalId":326183,"journal":{"name":"MTS/IEEE Oceans 2001. An Ocean Odyssey. Conference Proceedings (IEEE Cat. No.01CH37295)","volume":"71 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129270532","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 : 2001-11-05DOI: 10.1109/OCEANS.2001.968119
O. Colombo, A. Evans
In remote sensing over large areas with interferometric sonar, etc., that require high precision GPS geolocation, it is often desirable to achieve such precision in a short time. A technique for speeding up the convergence of the kinematic GPS navigation filter over long baselines has been tested. A buoy at sea has been positioned relative to base stations many hundreds of kilometers away. Sub-decimeter accuracy has been achieved in a few minutes, even when simultaneously relaxing the broadcast ephemeris to improve results. This fast convergence is commonplace in short-range surveys, when the vehicle is within 20 km of a base station, so it is possible to fix the carrier phase ambiguities to an exact number of cycles. But if a ship is operating in the high seas, achieving the same accuracy requires acquiring data for close to an hour, if carrier phase biases are "floated" in the usual way. In the method tested, the gradual change in mean sea level (after waves are filtered out) is used as a constraint to the solution.
{"title":"Precise, very long range marine positioning with GPS: achieving sub-decimeter precision in a matter of minutes","authors":"O. Colombo, A. Evans","doi":"10.1109/OCEANS.2001.968119","DOIUrl":"https://doi.org/10.1109/OCEANS.2001.968119","url":null,"abstract":"In remote sensing over large areas with interferometric sonar, etc., that require high precision GPS geolocation, it is often desirable to achieve such precision in a short time. A technique for speeding up the convergence of the kinematic GPS navigation filter over long baselines has been tested. A buoy at sea has been positioned relative to base stations many hundreds of kilometers away. Sub-decimeter accuracy has been achieved in a few minutes, even when simultaneously relaxing the broadcast ephemeris to improve results. This fast convergence is commonplace in short-range surveys, when the vehicle is within 20 km of a base station, so it is possible to fix the carrier phase ambiguities to an exact number of cycles. But if a ship is operating in the high seas, achieving the same accuracy requires acquiring data for close to an hour, if carrier phase biases are \"floated\" in the usual way. In the method tested, the gradual change in mean sea level (after waves are filtered out) is used as a constraint to the solution.","PeriodicalId":326183,"journal":{"name":"MTS/IEEE Oceans 2001. An Ocean Odyssey. Conference Proceedings (IEEE Cat. No.01CH37295)","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130878861","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}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：