Pub Date : 2015-10-29DOI: 10.1109/APSAR.2015.7306245
Zhirong Men, Pengbo Wang, Chunsheng Li
With the increasing demands for higher resolution and wider swath in many applications of Synthetic Aperture Radar (SAR), sliding spotlight mode has been presented. Here the antenna pattern is steered towards a fixed point to increase the synthetic aperture length and consequently in a better resolution. Currently, the image processing algorithms for sliding spotlight mode are almost based on the equivalent slant range model (ESRM). A great challenge has to be faced in signal processing of sliding spotlight mode. The ESRM, which is used for signal processing, may cause a Doppler parameter mismatch phenomenon and making an image quality decline at the edge of the scene when the swath coverage gets larger. In this paper, a modified imaging method based on nonuniform azimuth sampling is presented. First, a nonuniform azimuth sampling method is developed to compensate the Doppler parameter mismatch phenomenon. Second, a modified imaging method is proposed. Simulations are performed to validate the presented algorithm.
{"title":"Modified imaging method for high resolution wide swath spaceborne SAR based on nonuniform azimuth sampling","authors":"Zhirong Men, Pengbo Wang, Chunsheng Li","doi":"10.1109/APSAR.2015.7306245","DOIUrl":"https://doi.org/10.1109/APSAR.2015.7306245","url":null,"abstract":"With the increasing demands for higher resolution and wider swath in many applications of Synthetic Aperture Radar (SAR), sliding spotlight mode has been presented. Here the antenna pattern is steered towards a fixed point to increase the synthetic aperture length and consequently in a better resolution. Currently, the image processing algorithms for sliding spotlight mode are almost based on the equivalent slant range model (ESRM). A great challenge has to be faced in signal processing of sliding spotlight mode. The ESRM, which is used for signal processing, may cause a Doppler parameter mismatch phenomenon and making an image quality decline at the edge of the scene when the swath coverage gets larger. In this paper, a modified imaging method based on nonuniform azimuth sampling is presented. First, a nonuniform azimuth sampling method is developed to compensate the Doppler parameter mismatch phenomenon. Second, a modified imaging method is proposed. Simulations are performed to validate the presented algorithm.","PeriodicalId":350698,"journal":{"name":"2015 IEEE 5th Asia-Pacific Conference on Synthetic Aperture Radar (APSAR)","volume":"104 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115229153","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 : 2015-10-29DOI: 10.1109/APSAR.2015.7306187
H. Shao, Wen-qin Wang, Hui Chen
This paper compares four elevation multiple-input multiple-output (MIMO) synthetic aperture radar (SAR) antenna arrangements for wide-swath remote sensing. The signal models and range ambiguity function to signal ratio performance are comparatively compared, along with numerical results. It is shown that, when compared with conventional single-antenna SAR and existing multichannel SAR techniques, MIMO SAR indeed provides a potential solution for wide-swath remote sensing.
{"title":"Comparisons of MIMO SAR antenna arrangements in wide-swath remote sensing","authors":"H. Shao, Wen-qin Wang, Hui Chen","doi":"10.1109/APSAR.2015.7306187","DOIUrl":"https://doi.org/10.1109/APSAR.2015.7306187","url":null,"abstract":"This paper compares four elevation multiple-input multiple-output (MIMO) synthetic aperture radar (SAR) antenna arrangements for wide-swath remote sensing. The signal models and range ambiguity function to signal ratio performance are comparatively compared, along with numerical results. It is shown that, when compared with conventional single-antenna SAR and existing multichannel SAR techniques, MIMO SAR indeed provides a potential solution for wide-swath remote sensing.","PeriodicalId":350698,"journal":{"name":"2015 IEEE 5th Asia-Pacific Conference on Synthetic Aperture Radar (APSAR)","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124967226","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 : 2015-10-29DOI: 10.1109/APSAR.2015.7306299
M. Masaka, Y. Yamaguchi, Hiroyoshi Yamada
In this paper, the results of polarimetric scattering measurement is presented to verify the efficiency of proposed man-made object detection algorithm. The polarimetric angular indices α and β are known to be effective for identification of well-regulated structures. However, the validity for detecting deformed structures is not clear. So the feature of α and β for the squint angle variation of deformed man-made objects was investigated in detail.
{"title":"Experimental study on detecting deformed man-made objects based on eigenvalue/eigenvector analysis","authors":"M. Masaka, Y. Yamaguchi, Hiroyoshi Yamada","doi":"10.1109/APSAR.2015.7306299","DOIUrl":"https://doi.org/10.1109/APSAR.2015.7306299","url":null,"abstract":"In this paper, the results of polarimetric scattering measurement is presented to verify the efficiency of proposed man-made object detection algorithm. The polarimetric angular indices α and β are known to be effective for identification of well-regulated structures. However, the validity for detecting deformed structures is not clear. So the feature of α and β for the squint angle variation of deformed man-made objects was investigated in detail.","PeriodicalId":350698,"journal":{"name":"2015 IEEE 5th Asia-Pacific Conference on Synthetic Aperture Radar (APSAR)","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122809186","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 : 2015-10-29DOI: 10.1109/APSAR.2015.7306173
A. A. Pramudita
An Antenna with stable footprint is crucial for GPR system to perform. In regards to the problem of varying soil condition, the design of UWB reconfigurable antenna with footprint adjustment capability was studied as an antenna system for GPR. The antenna system consists of several U-shape micro strip UWB antennas with resistive loading. Reconfiguration of the propose antenna is performed by controlling the switching device which is used to connect each U-shape micro strip UWB antenna. The reconfiguration scheme gives possibility to adjust the antenna footprint by manipulated the effective aperture of the antenna. Larger footprint is generated by increasing the number of U-shape micro strip UWB that are connected to each other and vise versa for smaller footprint. The theoretical analysis has been done to investigate the reconfigurable antenna concept for footprint adjustment and the result shows that the reconfigurable antenna concept is capable to adjust the footprint size of the antenna.
{"title":"Reconfigurable antenna for footprint adjustment of the GPR system","authors":"A. A. Pramudita","doi":"10.1109/APSAR.2015.7306173","DOIUrl":"https://doi.org/10.1109/APSAR.2015.7306173","url":null,"abstract":"An Antenna with stable footprint is crucial for GPR system to perform. In regards to the problem of varying soil condition, the design of UWB reconfigurable antenna with footprint adjustment capability was studied as an antenna system for GPR. The antenna system consists of several U-shape micro strip UWB antennas with resistive loading. Reconfiguration of the propose antenna is performed by controlling the switching device which is used to connect each U-shape micro strip UWB antenna. The reconfiguration scheme gives possibility to adjust the antenna footprint by manipulated the effective aperture of the antenna. Larger footprint is generated by increasing the number of U-shape micro strip UWB that are connected to each other and vise versa for smaller footprint. The theoretical analysis has been done to investigate the reconfigurable antenna concept for footprint adjustment and the result shows that the reconfigurable antenna concept is capable to adjust the footprint size of the antenna.","PeriodicalId":350698,"journal":{"name":"2015 IEEE 5th Asia-Pacific Conference on Synthetic Aperture Radar (APSAR)","volume":"52 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128591536","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 : 2015-10-29DOI: 10.1109/APSAR.2015.7306218
Jinxing Chen, Bo Zhang, Chao Wang, Hong Zhang, Fan Wu
The grammar of facade structures is often related to regularly distributed signature patterns in high-resolution synthetic aperture radar (SAR) images. Given the structural details in the SAR image, algorithms for building extraction/monitoring should exploit this contextual information for an object-based analysis. In this paper we propose a framework to extract detailed high rise building features including building masks, orientations and stories. We developed a top-down approach which consists of processing at three levels, namely image level, region-of-interest (ROI) level and storey level. The analysis follows assumptions on the intensity distribution, the linear arrangement, and the regularity of point-like signatures. The proposed approach is validated using a high resolution staring spotlight TerraSAR-X image. A preliminary experiment for change detection using the extracted building features is also studied in this paper.
{"title":"Building features extraction based on facade regularities using TerraSAR-X ST data","authors":"Jinxing Chen, Bo Zhang, Chao Wang, Hong Zhang, Fan Wu","doi":"10.1109/APSAR.2015.7306218","DOIUrl":"https://doi.org/10.1109/APSAR.2015.7306218","url":null,"abstract":"The grammar of facade structures is often related to regularly distributed signature patterns in high-resolution synthetic aperture radar (SAR) images. Given the structural details in the SAR image, algorithms for building extraction/monitoring should exploit this contextual information for an object-based analysis. In this paper we propose a framework to extract detailed high rise building features including building masks, orientations and stories. We developed a top-down approach which consists of processing at three levels, namely image level, region-of-interest (ROI) level and storey level. The analysis follows assumptions on the intensity distribution, the linear arrangement, and the regularity of point-like signatures. The proposed approach is validated using a high resolution staring spotlight TerraSAR-X image. A preliminary experiment for change detection using the extracted building features is also studied in this paper.","PeriodicalId":350698,"journal":{"name":"2015 IEEE 5th Asia-Pacific Conference on Synthetic Aperture Radar (APSAR)","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116312457","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 : 2015-10-29DOI: 10.1109/APSAR.2015.7306188
Xiaoli Wu, Wei Wang, Qi Chen, Bin Cai, Xue Bai
Geosynchronous Synthetic Aperture Radar (GEO-SAR) shows great potential in both civil and military applications, but it suffers from high energy requirement and difficult signal processing procedure. For the purpose of reducing energy requirement, this paper firstly analyze the carrier frequency selection problem and the burst mode of GEO-SAR on the basis of which an S band GEO-SAR system operating on burst mode is subsequently proposed. Moreover, an effective focus algorithm adapting to the GEO-SAR system is described. Simulation results based on the space-borne radar advance simulator (SBRAS) demonstrate the validity of proposed GEO-SAR system and focus algorithm.
{"title":"The burst mode of geosynchronous synthetic aperture radar","authors":"Xiaoli Wu, Wei Wang, Qi Chen, Bin Cai, Xue Bai","doi":"10.1109/APSAR.2015.7306188","DOIUrl":"https://doi.org/10.1109/APSAR.2015.7306188","url":null,"abstract":"Geosynchronous Synthetic Aperture Radar (GEO-SAR) shows great potential in both civil and military applications, but it suffers from high energy requirement and difficult signal processing procedure. For the purpose of reducing energy requirement, this paper firstly analyze the carrier frequency selection problem and the burst mode of GEO-SAR on the basis of which an S band GEO-SAR system operating on burst mode is subsequently proposed. Moreover, an effective focus algorithm adapting to the GEO-SAR system is described. Simulation results based on the space-borne radar advance simulator (SBRAS) demonstrate the validity of proposed GEO-SAR system and focus algorithm.","PeriodicalId":350698,"journal":{"name":"2015 IEEE 5th Asia-Pacific Conference on Synthetic Aperture Radar (APSAR)","volume":"101 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131933883","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 : 2015-10-29DOI: 10.1109/APSAR.2015.7306279
Ying Deng, Hong Zhang, Chao Wang, Meng Liu
Synthetic Aperture Radar (SAR), with all-weather and all-time imaging capabilities, provides a stable data resource for environmental monitoring. In water related applications, obtaining precise water areas from SAR data is essential. This paper presents a high accuracy water extraction scheme based on Object-Oriented technique. First, a watershed segmentation is used for preserve waterlines. Then, a decomposition method is applied to identify water features. Afterwards, a majority voting strategy is utilized for water segment recognition. A set of Radarsat-2 data is used to verify the efficiency of the proposed method. And a pixel-based scheme and a proposed method without the majority voting step are applied for comparison. The experimental results indicate that the segmentation is able to maintain accurate waterline, while the voting strategy is capable of detecting small water area.
{"title":"Object-oriented water extraction of PolSAR image based on target decomposition","authors":"Ying Deng, Hong Zhang, Chao Wang, Meng Liu","doi":"10.1109/APSAR.2015.7306279","DOIUrl":"https://doi.org/10.1109/APSAR.2015.7306279","url":null,"abstract":"Synthetic Aperture Radar (SAR), with all-weather and all-time imaging capabilities, provides a stable data resource for environmental monitoring. In water related applications, obtaining precise water areas from SAR data is essential. This paper presents a high accuracy water extraction scheme based on Object-Oriented technique. First, a watershed segmentation is used for preserve waterlines. Then, a decomposition method is applied to identify water features. Afterwards, a majority voting strategy is utilized for water segment recognition. A set of Radarsat-2 data is used to verify the efficiency of the proposed method. And a pixel-based scheme and a proposed method without the majority voting step are applied for comparison. The experimental results indicate that the segmentation is able to maintain accurate waterline, while the voting strategy is capable of detecting small water area.","PeriodicalId":350698,"journal":{"name":"2015 IEEE 5th Asia-Pacific Conference on Synthetic Aperture Radar (APSAR)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130113717","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 : 2015-10-29DOI: 10.1109/APSAR.2015.7306241
Wei Yang, Dalu Liu
This paper concentrates on the image formation algorithm for TOP (Terrain Observation by Progressive Scans) mode data processing, which ensures both the quality of focusing and the phase accuracy. Based on the three-step processing schedule, the de-rotation operation is adopted to conquer the overlap in azimuth frequency domain, and the antenna sweep rate is discussed in tail. Moreover, the classic focusing kernel is applied for range and azimuth compressing. Furthermore, phase and compression-gain compensation function is given, which is implemented after deramp operation. Finally, the simulation results justify the effectiveness and precision of the proposed phase-preserving algorithm.
本文重点研究了TOP (Terrain Observation by Progressive Scans)模式数据处理的成像算法，该算法既保证了对焦质量，又保证了相位精度。基于三步处理计划，在方位角频域采用去旋转操作克服重叠，并在尾端讨论天线扫描速率。此外，采用经典的聚焦核进行距离和方位压缩。此外，还给出了相位和压缩增益补偿函数，该函数在脱放后实现。最后，仿真结果验证了所提保相算法的有效性和精度。
{"title":"A pricise phase-preserving image formation algorithm for topsar data processing","authors":"Wei Yang, Dalu Liu","doi":"10.1109/APSAR.2015.7306241","DOIUrl":"https://doi.org/10.1109/APSAR.2015.7306241","url":null,"abstract":"This paper concentrates on the image formation algorithm for TOP (Terrain Observation by Progressive Scans) mode data processing, which ensures both the quality of focusing and the phase accuracy. Based on the three-step processing schedule, the de-rotation operation is adopted to conquer the overlap in azimuth frequency domain, and the antenna sweep rate is discussed in tail. Moreover, the classic focusing kernel is applied for range and azimuth compressing. Furthermore, phase and compression-gain compensation function is given, which is implemented after deramp operation. Finally, the simulation results justify the effectiveness and precision of the proposed phase-preserving algorithm.","PeriodicalId":350698,"journal":{"name":"2015 IEEE 5th Asia-Pacific Conference on Synthetic Aperture Radar (APSAR)","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115468520","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 : 2015-10-29DOI: 10.1109/APSAR.2015.7306162
A. Torre
Thales Alenia Space (TAS) has started the “COMPACT-SAR” internal programme to develop a SAR satellite characterized by low cost and reduced mass while providing, at the same time, high image quality in terms of resolution, swath size, and radiometric performance. COMPACT-SAR is a satellite embarking an X-band SAR based on a new technology for the Antenna Subsystem. It consists of an innovative deployable reflector antenna fed by a small active phased array, capable of electronic beam steering in both azimuth and elevation planes. Thanks to this design, the instrument can be operated in both STRIPMAP, DI2S (i.e. enhanced resolution STRIPMAP) and SPOTLIGHT modes. Due to the very high gain provided by the large reflector, the system can also provide a real maritime surveillance mode based on the TAS patented LowPRF mode. The flexibility of the design, based on the large (5m) on-set reflector is also exploited to define a version of the product operating at L-band just by changing the feed array and the RF back-end of the radar. TAS already has a product line on T/R modules at L (and C) band, allowing this new development with minimum risk.
{"title":"Compact SAR: A flexible multimission SAR satellite","authors":"A. Torre","doi":"10.1109/APSAR.2015.7306162","DOIUrl":"https://doi.org/10.1109/APSAR.2015.7306162","url":null,"abstract":"Thales Alenia Space (TAS) has started the “COMPACT-SAR” internal programme to develop a SAR satellite characterized by low cost and reduced mass while providing, at the same time, high image quality in terms of resolution, swath size, and radiometric performance. COMPACT-SAR is a satellite embarking an X-band SAR based on a new technology for the Antenna Subsystem. It consists of an innovative deployable reflector antenna fed by a small active phased array, capable of electronic beam steering in both azimuth and elevation planes. Thanks to this design, the instrument can be operated in both STRIPMAP, DI2S (i.e. enhanced resolution STRIPMAP) and SPOTLIGHT modes. Due to the very high gain provided by the large reflector, the system can also provide a real maritime surveillance mode based on the TAS patented LowPRF mode. The flexibility of the design, based on the large (5m) on-set reflector is also exploited to define a version of the product operating at L-band just by changing the feed array and the RF back-end of the radar. TAS already has a product line on T/R modules at L (and C) band, allowing this new development with minimum risk.","PeriodicalId":350698,"journal":{"name":"2015 IEEE 5th Asia-Pacific Conference on Synthetic Aperture Radar (APSAR)","volume":"314 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115880884","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 : 2015-10-29DOI: 10.1109/APSAR.2015.7306184
L. Marotti, A. Meta, A. Coccia
Interferometric SAR (InSAR) techniques are an important tool for the generation of three-dimensional topographic maps of the Earth. Synthetic Aperture Radar sensors operated on airborne platforms can deliver high quality data for the generation of the Digital Surface Model as well as for the Digital Elevation Models. This paper describe the procedures and algorithms to generate the Digital Surface Model from MetaSensing airborne SAR sensors at X- and Ku-band with single pass.
{"title":"MetaSensing airborne radar: X- and Ku-band single-pass digital surface model generation","authors":"L. Marotti, A. Meta, A. Coccia","doi":"10.1109/APSAR.2015.7306184","DOIUrl":"https://doi.org/10.1109/APSAR.2015.7306184","url":null,"abstract":"Interferometric SAR (InSAR) techniques are an important tool for the generation of three-dimensional topographic maps of the Earth. Synthetic Aperture Radar sensors operated on airborne platforms can deliver high quality data for the generation of the Digital Surface Model as well as for the Digital Elevation Models. This paper describe the procedures and algorithms to generate the Digital Surface Model from MetaSensing airborne SAR sensors at X- and Ku-band with single pass.","PeriodicalId":350698,"journal":{"name":"2015 IEEE 5th Asia-Pacific Conference on Synthetic Aperture Radar (APSAR)","volume":"53 41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124152860","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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