High-Resolution Wide-Swath Ambiguous Synthetic Aperture Radar Modes for Ship Monitoring
This paper proposes two high-resolution, wide-swath synthetic aperture radar (SAR) acquisition modes for ship monitoring that tolerate ambiguities and do not require digital beamforming. Both modes, referred to as the low pulse repetition frequency (PRF) and the staggered (high PRF) ambiguous modes,...
| Main Authors: | , |
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| Format: | Article |
| Language: | English |
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MDPI AG
2022-06-01
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| Series: | Remote Sensing |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2072-4292/14/13/3102 |
| _version_ | 1797408230931955712 |
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| author | Nertjana Ustalli Michelangelo Villano |
| author_facet | Nertjana Ustalli Michelangelo Villano |
| author_sort | Nertjana Ustalli |
| collection | DOAJ |
| description | This paper proposes two high-resolution, wide-swath synthetic aperture radar (SAR) acquisition modes for ship monitoring that tolerate ambiguities and do not require digital beamforming. Both modes, referred to as the low pulse repetition frequency (PRF) and the staggered (high PRF) ambiguous modes, make use of a wide elevation beam, which can be obtained by phase tapering. The first mode is a conventional stripmap mode with a PRF much lower than the nominal Doppler bandwidth, allowing for the imaging of a large swath, because the ships’ azimuth ambiguities can be recognized as they appear at known positions. The second mode exploits a continuous variation of the pulse repetition interval, with a mean PRF greater than the nominal Doppler bandwidth as the range ambiguities of the ships are smeared and are unlikely to determine false alarms. Both modes are thought to operate in open sea surveillance, monitoring Exclusive Economic Zones or international waters. Examples of implementation of both modes for TerraSAR-X show that ground swaths of 120 km or 240 km can be mapped with 2 m<sup>2</sup> resolution, ensuring outstanding detection performance even for small ships. The importance of resolution over noise and ambiguity level was highlighted by a comparison with ScanSAR modes that image comparable swaths with better noise and ambiguity levels but coarser resolutions. |
| first_indexed | 2024-03-09T03:55:24Z |
| format | Article |
| id | doaj.art-3c3f8bb5eb1a4c50a67afac5912c069e |
| institution | Directory Open Access Journal |
| issn | 2072-4292 |
| language | English |
| last_indexed | 2024-03-09T03:55:24Z |
| publishDate | 2022-06-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Remote Sensing |
| spelling | doaj.art-3c3f8bb5eb1a4c50a67afac5912c069e2023-12-03T14:20:34ZengMDPI AGRemote Sensing2072-42922022-06-011413310210.3390/rs14133102High-Resolution Wide-Swath Ambiguous Synthetic Aperture Radar Modes for Ship MonitoringNertjana Ustalli0Michelangelo Villano1Microwaves and Radar Institute, German Aerospace Center (DLR), 82234 Wessling, GermanyMicrowaves and Radar Institute, German Aerospace Center (DLR), 82234 Wessling, GermanyThis paper proposes two high-resolution, wide-swath synthetic aperture radar (SAR) acquisition modes for ship monitoring that tolerate ambiguities and do not require digital beamforming. Both modes, referred to as the low pulse repetition frequency (PRF) and the staggered (high PRF) ambiguous modes, make use of a wide elevation beam, which can be obtained by phase tapering. The first mode is a conventional stripmap mode with a PRF much lower than the nominal Doppler bandwidth, allowing for the imaging of a large swath, because the ships’ azimuth ambiguities can be recognized as they appear at known positions. The second mode exploits a continuous variation of the pulse repetition interval, with a mean PRF greater than the nominal Doppler bandwidth as the range ambiguities of the ships are smeared and are unlikely to determine false alarms. Both modes are thought to operate in open sea surveillance, monitoring Exclusive Economic Zones or international waters. Examples of implementation of both modes for TerraSAR-X show that ground swaths of 120 km or 240 km can be mapped with 2 m<sup>2</sup> resolution, ensuring outstanding detection performance even for small ships. The importance of resolution over noise and ambiguity level was highlighted by a comparison with ScanSAR modes that image comparable swaths with better noise and ambiguity levels but coarser resolutions.https://www.mdpi.com/2072-4292/14/13/3102ambiguitieshigh-resolution wide-swath imagingpulse repetition frequency (PRF)ship detectionstaggeredsynthetic aperture radar (SAR) |
| spellingShingle | Nertjana Ustalli Michelangelo Villano High-Resolution Wide-Swath Ambiguous Synthetic Aperture Radar Modes for Ship Monitoring Remote Sensing ambiguities high-resolution wide-swath imaging pulse repetition frequency (PRF) ship detection staggered synthetic aperture radar (SAR) |
| title | High-Resolution Wide-Swath Ambiguous Synthetic Aperture Radar Modes for Ship Monitoring |
| title_full | High-Resolution Wide-Swath Ambiguous Synthetic Aperture Radar Modes for Ship Monitoring |
| title_fullStr | High-Resolution Wide-Swath Ambiguous Synthetic Aperture Radar Modes for Ship Monitoring |
| title_full_unstemmed | High-Resolution Wide-Swath Ambiguous Synthetic Aperture Radar Modes for Ship Monitoring |
| title_short | High-Resolution Wide-Swath Ambiguous Synthetic Aperture Radar Modes for Ship Monitoring |
| title_sort | high resolution wide swath ambiguous synthetic aperture radar modes for ship monitoring |
| topic | ambiguities high-resolution wide-swath imaging pulse repetition frequency (PRF) ship detection staggered synthetic aperture radar (SAR) |
| url | https://www.mdpi.com/2072-4292/14/13/3102 |
| work_keys_str_mv | AT nertjanaustalli highresolutionwideswathambiguoussyntheticapertureradarmodesforshipmonitoring AT michelangelovillano highresolutionwideswathambiguoussyntheticapertureradarmodesforshipmonitoring |