Pub Date : 2014-10-01DOI: 10.1109/RADAR.2014.7060444
Lu Xiaode, Li Jichuan, Lin Kuan, Li Daojing, Zhang Yi
The direct path signal, strong multi-path and strong moving target echoes can mask the weak target in passive coherent location (PCL) radar systems. The classical normalized least-mean squares (NLMS) algorithm is widely used in cancelling the direct path and multi-path interferences in PCL radar systems, which cannot suppress the stationary ground clutter and the strong moving target echoes simultaneously. An improved NLMS algorithm, called range-Doppler NLMS (RDNLMS), is proposed for cancelling the interferences with different delays (denoting the range information) and Doppler frequencies in PCL radar systems utilizing the Chinese digital television terrestrial broadcasting (DTTB) transmissions. The validity of the algorithm is verified by the simulative results.
{"title":"Range-Doppler NLMS (RDNLMS) algorithm for cancellation of strong moving targets in passive coherent location (PCL) radar","authors":"Lu Xiaode, Li Jichuan, Lin Kuan, Li Daojing, Zhang Yi","doi":"10.1109/RADAR.2014.7060444","DOIUrl":"https://doi.org/10.1109/RADAR.2014.7060444","url":null,"abstract":"The direct path signal, strong multi-path and strong moving target echoes can mask the weak target in passive coherent location (PCL) radar systems. The classical normalized least-mean squares (NLMS) algorithm is widely used in cancelling the direct path and multi-path interferences in PCL radar systems, which cannot suppress the stationary ground clutter and the strong moving target echoes simultaneously. An improved NLMS algorithm, called range-Doppler NLMS (RDNLMS), is proposed for cancelling the interferences with different delays (denoting the range information) and Doppler frequencies in PCL radar systems utilizing the Chinese digital television terrestrial broadcasting (DTTB) transmissions. The validity of the algorithm is verified by the simulative results.","PeriodicalId":317910,"journal":{"name":"2014 International Radar Conference","volume":"237 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133805725","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 : 2014-10-01DOI: 10.1109/RADAR.2014.7060297
Johanna Guetlein-Holzer, A. Kirschner, Christian Speck, J. Detlefsen
For a multiple input multiple output (MIMO) radar system that uses a frequency modulated continuous wave (FMCW) signal and time domain multiplexing (TDM), different effects occur in the presence of relative motion between radar system and target. These effects have an influence on the correct position detection of the targets. Therefore, two different modulation schemes are analyzed that have the ability to overcome the issues of movement and estimate the correct target location and velocity.
{"title":"Comparison of motion compensation methods applied to a TDM FMCW MIMO radar system","authors":"Johanna Guetlein-Holzer, A. Kirschner, Christian Speck, J. Detlefsen","doi":"10.1109/RADAR.2014.7060297","DOIUrl":"https://doi.org/10.1109/RADAR.2014.7060297","url":null,"abstract":"For a multiple input multiple output (MIMO) radar system that uses a frequency modulated continuous wave (FMCW) signal and time domain multiplexing (TDM), different effects occur in the presence of relative motion between radar system and target. These effects have an influence on the correct position detection of the targets. Therefore, two different modulation schemes are analyzed that have the ability to overcome the issues of movement and estimate the correct target location and velocity.","PeriodicalId":317910,"journal":{"name":"2014 International Radar Conference","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133808411","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 : 2014-10-01DOI: 10.1109/RADAR.2014.7060333
O. Rabaste, L. Savy
In this article, we consider the problem of computing the optimal mismatched filter with respect to the Peak-to-SideLobe Ratio (PSLR). We propose to solve this problem via a convex quadratically constrained quadratic program that permits to obtain an optimal solution of the problem. The solution is obtain numerically by interior point methods. We show that this convex program can be modified to take into account additional constraints, for instance on the loss in processing gain, the mainlobe or sidelobe shapes and the Integrated Sidelobe Level. This strategy is applied to solve the PSLR problem for phase codes in radar applications, and for antenna arrays with a non negligible number of defective antennas. The results obtained show an interesting improvement of the PSLR for a predefined acceptable loss in processing gain, for both applications.
{"title":"Mismatched filter optimization via quadratic convex programming for radar applications","authors":"O. Rabaste, L. Savy","doi":"10.1109/RADAR.2014.7060333","DOIUrl":"https://doi.org/10.1109/RADAR.2014.7060333","url":null,"abstract":"In this article, we consider the problem of computing the optimal mismatched filter with respect to the Peak-to-SideLobe Ratio (PSLR). We propose to solve this problem via a convex quadratically constrained quadratic program that permits to obtain an optimal solution of the problem. The solution is obtain numerically by interior point methods. We show that this convex program can be modified to take into account additional constraints, for instance on the loss in processing gain, the mainlobe or sidelobe shapes and the Integrated Sidelobe Level. This strategy is applied to solve the PSLR problem for phase codes in radar applications, and for antenna arrays with a non negligible number of defective antennas. The results obtained show an interesting improvement of the PSLR for a predefined acceptable loss in processing gain, for both applications.","PeriodicalId":317910,"journal":{"name":"2014 International Radar Conference","volume":"96 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114622616","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 : 2014-10-01DOI: 10.1109/RADAR.2014.7060413
E. Brookner
Contrary to claims made Multiple Input and Multiple Output (MIMO) radars do not provide an order of magnitude or better angle resolution, accuracy and identifiability (the ability to resolve and identify targets) over conventional radars. This claim for MIMO results from making the wrong of a full/thin MIMO array to a full conventional array rather than to a conventional full/thin array. It is shown here that a conventional full/thin array radar can have the same angle accuracy, resolution and identifiability as a MIMO full/thin array. Where does the MIMO radar provide a better angle accuracy than a conventional radar? A monostatic MIMO array radar does provide a better angle accuracy than its conventional monostatic equivalent, but it is only about a factor of 1/√2 (29 percent) better and its resolution is the same. Contrary to what may be thought MIMO does not offer an advantage re barrage noise jammers or hot clutter (a jammer scattered from the ground) over a conventional array. It does offer a potential advantage re strong clutter because nulls can be adaptively put in the transmit pattern in the direction of the clutter. However this type clutter can be handled in conventional arrays by putting nulls in the direction of the clutter whose location is known.
{"title":"MIMO radar demystified and where it makes sense to use","authors":"E. Brookner","doi":"10.1109/RADAR.2014.7060413","DOIUrl":"https://doi.org/10.1109/RADAR.2014.7060413","url":null,"abstract":"Contrary to claims made Multiple Input and Multiple Output (MIMO) radars do not provide an order of magnitude or better angle resolution, accuracy and identifiability (the ability to resolve and identify targets) over conventional radars. This claim for MIMO results from making the wrong of a full/thin MIMO array to a full conventional array rather than to a conventional full/thin array. It is shown here that a conventional full/thin array radar can have the same angle accuracy, resolution and identifiability as a MIMO full/thin array. Where does the MIMO radar provide a better angle accuracy than a conventional radar? A monostatic MIMO array radar does provide a better angle accuracy than its conventional monostatic equivalent, but it is only about a factor of 1/√2 (29 percent) better and its resolution is the same. Contrary to what may be thought MIMO does not offer an advantage re barrage noise jammers or hot clutter (a jammer scattered from the ground) over a conventional array. It does offer a potential advantage re strong clutter because nulls can be adaptively put in the transmit pattern in the direction of the clutter. However this type clutter can be handled in conventional arrays by putting nulls in the direction of the clutter whose location is known.","PeriodicalId":317910,"journal":{"name":"2014 International Radar Conference","volume":"111 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124740697","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 : 2014-10-01DOI: 10.1109/RADAR.2014.7060257
D. Staglianò, E. Giusti, S. Lischi, M. Martorella
A 3D reconstruction algorithm for non cooperative moving targets is proposed in this paper. This method exploits interferometric ISAR imaging (InISAR) to estimate the heights of the dominant scatterers with respect t o the Image Projection Plane. In particular, the interferometric phases measured from two orthogonal baselines are used to reconstruct t he third dimension from 2D-ISAR images. Some aspects that make such approach effective in a real scenario have been faced and their problems solved. In order to verify the effectiveness and the reliability of this technique, data from a suitably designed Multi-Channel ground-based radar has been used.
{"title":"3D InISAR-based target reconstruction algorithm by using a Multi-Channel ground-based radar demonstrator","authors":"D. Staglianò, E. Giusti, S. Lischi, M. Martorella","doi":"10.1109/RADAR.2014.7060257","DOIUrl":"https://doi.org/10.1109/RADAR.2014.7060257","url":null,"abstract":"A 3D reconstruction algorithm for non cooperative moving targets is proposed in this paper. This method exploits interferometric ISAR imaging (InISAR) to estimate the heights of the dominant scatterers with respect t o the Image Projection Plane. In particular, the interferometric phases measured from two orthogonal baselines are used to reconstruct t he third dimension from 2D-ISAR images. Some aspects that make such approach effective in a real scenario have been faced and their problems solved. In order to verify the effectiveness and the reliability of this technique, data from a suitably designed Multi-Channel ground-based radar has been used.","PeriodicalId":317910,"journal":{"name":"2014 International Radar Conference","volume":"52 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124756896","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 : 2014-10-01DOI: 10.1109/RADAR.2014.7060277
A. Glascott-Jones, N. Chantier, F. Bore, M. Wingender, M. Stackler, J. Amblard, E. Bouin, V. Monier, M. Martin, G. Jestin
This work presents a new high speed, high bandwidth Digital to Analog Converter (DAC) which enables the direct conversion of wideband Radar chirp waveforms to frequencies up to band X. The component features a number of innovative design features which enable the optimization of performance in the different Nyquist zones. These include various output shaping schemes and interface methods. Preliminary results are provided which show the performance of the circuit at output frequencies greater than 7GHz. Digital chirp patterns have been created for this component and the results of these patterns output by the DAC are presented along with the ability of the component in high speed switching applications. The component's performance can result in highly flexible and waveform agile Radar signal generation systems.
{"title":"Direct conversion to X band using a 4.5 GSps SiGe Digital to Analog Converter","authors":"A. Glascott-Jones, N. Chantier, F. Bore, M. Wingender, M. Stackler, J. Amblard, E. Bouin, V. Monier, M. Martin, G. Jestin","doi":"10.1109/RADAR.2014.7060277","DOIUrl":"https://doi.org/10.1109/RADAR.2014.7060277","url":null,"abstract":"This work presents a new high speed, high bandwidth Digital to Analog Converter (DAC) which enables the direct conversion of wideband Radar chirp waveforms to frequencies up to band X. The component features a number of innovative design features which enable the optimization of performance in the different Nyquist zones. These include various output shaping schemes and interface methods. Preliminary results are provided which show the performance of the circuit at output frequencies greater than 7GHz. Digital chirp patterns have been created for this component and the results of these patterns output by the DAC are presented along with the ability of the component in high speed switching applications. The component's performance can result in highly flexible and waveform agile Radar signal generation systems.","PeriodicalId":317910,"journal":{"name":"2014 International Radar Conference","volume":"71 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125210309","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 : 2014-10-01DOI: 10.1109/RADAR.2014.7060420
S. Torres, Ric Adams, C. Curtis, Eddie Forren, D. Forsyth, I. Ivić, D. Priegnitz, J. Thompson, D. Warde
This paper describes the latest adaptive scanning and multifunction capabilities of the National Weather Radar Testbed Phased-Array Radar located in Norman, Oklahoma (USA). Proof-of-concept focused and tailored observations of weather and scheduling algorithms for multifunction operation are described, and their performance is illustrated with real-data examples. It is demonstrated that adaptive scanning of weather is feasible in a multifunction radar and has the potential to reduce revisit times and to provide meteorological data that can aid in the forecaster's warning-decision process.
{"title":"A demonstration of adaptive weather surveillance and multifunction capabilities on the National Weather Radar Testbed Phased Array Radar","authors":"S. Torres, Ric Adams, C. Curtis, Eddie Forren, D. Forsyth, I. Ivić, D. Priegnitz, J. Thompson, D. Warde","doi":"10.1109/RADAR.2014.7060420","DOIUrl":"https://doi.org/10.1109/RADAR.2014.7060420","url":null,"abstract":"This paper describes the latest adaptive scanning and multifunction capabilities of the National Weather Radar Testbed Phased-Array Radar located in Norman, Oklahoma (USA). Proof-of-concept focused and tailored observations of weather and scheduling algorithms for multifunction operation are described, and their performance is illustrated with real-data examples. It is demonstrated that adaptive scanning of weather is feasible in a multifunction radar and has the potential to reduce revisit times and to provide meteorological data that can aid in the forecaster's warning-decision process.","PeriodicalId":317910,"journal":{"name":"2014 International Radar Conference","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126444259","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 : 2014-10-01DOI: 10.1109/RADAR.2014.7060466
B. Souissi, M. Ouarzeddine, Houda Latreche
In this paper a practical method is demonstrated for estimating terrain slopes in azimuth and ground range directions for digital elevation model (DEM) generation without any prior knowledge on the terrain by using only one single pass of polarimetric synthetic aperture radar (PolSAR) instead of two-pass or interferometric SAR (INSAR). The basic approach is by combing the orientation angle estimation and a shape-from-shading technique (SFS) which is mostly used by the computer vision community. In particular, when limited PolSAR data are available, this technique provides an alternative way for DEM generation. The polarization orientation angle (POA) is related to both the range and azimulh angles of the tilted surface and radar viewing angle and it can be estimated from the PolSAR data by using the circular polarization method which shows the best performance in computation efficiency and accuracy with respect to the other methods. After terrain slopes in both the range and azimuth directions have been estimated initially by the combination of the POA estimation and the SFS algorithm, a least squares method similar to that used in interferometric phase unwrapping is used to generate the topography. The least squares approach to phase unwrapping obtains an unwrapped solution by minimizing the differences between the discrete partial derivatives of the (wrapped) phase data and the discrete partial derivatives of the unwrapped solution. We illustrate our results by using the polarimetric SAR images acquired in Algeria by the RadarSAT2 (FQ19) in C-band.
{"title":"Estimation of surface topography from single polarimetric SAR imagery using RADARSAT2","authors":"B. Souissi, M. Ouarzeddine, Houda Latreche","doi":"10.1109/RADAR.2014.7060466","DOIUrl":"https://doi.org/10.1109/RADAR.2014.7060466","url":null,"abstract":"In this paper a practical method is demonstrated for estimating terrain slopes in azimuth and ground range directions for digital elevation model (DEM) generation without any prior knowledge on the terrain by using only one single pass of polarimetric synthetic aperture radar (PolSAR) instead of two-pass or interferometric SAR (INSAR). The basic approach is by combing the orientation angle estimation and a shape-from-shading technique (SFS) which is mostly used by the computer vision community. In particular, when limited PolSAR data are available, this technique provides an alternative way for DEM generation. The polarization orientation angle (POA) is related to both the range and azimulh angles of the tilted surface and radar viewing angle and it can be estimated from the PolSAR data by using the circular polarization method which shows the best performance in computation efficiency and accuracy with respect to the other methods. After terrain slopes in both the range and azimuth directions have been estimated initially by the combination of the POA estimation and the SFS algorithm, a least squares method similar to that used in interferometric phase unwrapping is used to generate the topography. The least squares approach to phase unwrapping obtains an unwrapped solution by minimizing the differences between the discrete partial derivatives of the (wrapped) phase data and the discrete partial derivatives of the unwrapped solution. We illustrate our results by using the polarimetric SAR images acquired in Algeria by the RadarSAT2 (FQ19) in C-band.","PeriodicalId":317910,"journal":{"name":"2014 International Radar Conference","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125799125","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 : 2014-10-01DOI: 10.1109/RADAR.2014.7060447
Huikai Zang, Hongwei Liu, Shenghua Zhou, Xu Wang
Multiple-input multiple-output (MIMO) radar has been intensively studied recently and an interesting issue is to design waveforms for a desirable transmitting beampattern and a low sidelobe level. In this paper, for a given colocated MIMO radar system, we propose an algorithm that takes the receiving beamforming into consideration in waveform design. With cross-correlation sidelobes suppressed in receiving beamforming, the optimization algorithm can places more degrees of freedom on suppressing other components and thus a better result can be obtained. The performance of this method is evaluated for both omnidirectional and directional transmitting beampatterns.
{"title":"MIMO radar waveform design involving receiving beamforming","authors":"Huikai Zang, Hongwei Liu, Shenghua Zhou, Xu Wang","doi":"10.1109/RADAR.2014.7060447","DOIUrl":"https://doi.org/10.1109/RADAR.2014.7060447","url":null,"abstract":"Multiple-input multiple-output (MIMO) radar has been intensively studied recently and an interesting issue is to design waveforms for a desirable transmitting beampattern and a low sidelobe level. In this paper, for a given colocated MIMO radar system, we propose an algorithm that takes the receiving beamforming into consideration in waveform design. With cross-correlation sidelobes suppressed in receiving beamforming, the optimization algorithm can places more degrees of freedom on suppressing other components and thus a better result can be obtained. The performance of this method is evaluated for both omnidirectional and directional transmitting beampatterns.","PeriodicalId":317910,"journal":{"name":"2014 International Radar Conference","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129981564","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 : 2014-10-01DOI: 10.1109/RADAR.2014.7060411
V. Chernyak
The problem of fluctuating signal detection in a background of spatially correlated interferences for MIMO radars with colocated antennas is considered. Optimum (LRT) algorithms are analyzed. A system of narrow receiving beams in MIMO radars without space scanning realizes preliminary spatial filtration: separation of targets and sidelobe interference sources. As a result, the complicated optimal detection algorithms with interference cancellation may be replaced by the simpler suboptimal algorithm. Comparative analysis of the optimal and suboptimal detection algorithms presented in the paper shows insignificant energy loss for the latter one.
{"title":"Spatially correlated interference cancellation and target detection by MIMO radars","authors":"V. Chernyak","doi":"10.1109/RADAR.2014.7060411","DOIUrl":"https://doi.org/10.1109/RADAR.2014.7060411","url":null,"abstract":"The problem of fluctuating signal detection in a background of spatially correlated interferences for MIMO radars with colocated antennas is considered. Optimum (LRT) algorithms are analyzed. A system of narrow receiving beams in MIMO radars without space scanning realizes preliminary spatial filtration: separation of targets and sidelobe interference sources. As a result, the complicated optimal detection algorithms with interference cancellation may be replaced by the simpler suboptimal algorithm. Comparative analysis of the optimal and suboptimal detection algorithms presented in the paper shows insignificant energy loss for the latter one.","PeriodicalId":317910,"journal":{"name":"2014 International Radar Conference","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130031993","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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