- 标题
- 摘要
- 关键词
- 实验方案
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Based on Spectrum Modeling and Optimization
摘要： Bistatic synthetic aperture radar (SAR) is able to break through the limitation of monostatic SAR on forward-looking area imaging with appropriate geometry configurations. Thanks to such an ability, bistatic forward-looking SAR (BFSAR) has extensive potential practical applications. For the focusing problem of conventional side-looking SAR, ω–k algorithm is accepted as the ideal solution. In this paper, the ω–k algorithm will be discussed in BFSAR geometry. As for the bistatic configuration, spatial domain linearization procedure should be carried out to extract a range variable from the point target reference spectrum (PTRS) in the existing ω–k algorithms. With respect to the BFSAR geometry, nevertheless, the linearization procedure reduces the accuracy of PTRS seriously. To cope with such a problem, a novel ω–k algorithm for BFSAR is proposed. In the proposed method, the range variable is modeled as a parameterized polynomial, and the corresponding PTRS with respect to two-dimensional frequencies is established. Then, the parameters are estimated by differential evolution to minimize the PTRS errors for each range coordinate and frequency point. Based on the estimated PTRS, the BFSAR data can be focused well by the proposed ω–k algorithm. Simulation results verify the effectiveness of the proposed method.
关键词： Bistatic forward-looking synthetic aperture radar (BFSAR),differential evolution (DE),ω–k,point target reference spectrum (PTRS)
更新于2025-09-23 15:23:52
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[IEEE IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Valencia (2018.7.22-2018.7.27)] IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Coastal Application of Sea Surface Height Measurement Using Direct Broadcast Satellite Signals
摘要： This paper presents results from a proof-of-concept experiment conducted at Platform Harvest to measure Sea Surface Height (SSH) using Ku- and K-band 'Signals of Opportunity' (SoOp) from DirecTV Direct Broadcast Satellite (DBS) system. The retrieved SSH was compared with the SSH measurement from a tide gauge located at the platform; the error in retrieval of Ku-band and K-band was found to be 2.78 cm and 2.58 cm, respectively. This matched the model for error with some differences that can be attributed to the difference in spatial and temporal characteristics of the SoOp and tide gauge measurements. Finally, this paper gives an overview of temporal and spatial sampling possible from a constellation of receivers observing Ku-band SoOp to resolve mesoscale eddies in coastal regions.
关键词： bistatic radar,Wideband Signals of Opportunity,coastal altimetry
更新于2025-09-23 15:23:52
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[IEEE IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Valencia (2018.7.22-2018.7.27)] IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Spacecraft Formation Design for Bistatic SAR with GEO Illuminator and LEO Receiver
摘要： The bistatic synthetic aperture radar (BiSAR) system consists of a geosynchronous Earth orbit (GEO) illuminator and a low Earth orbit (LEO) receiver. Compared with GEO SAR, it offers great advantages of higher signal-to-noise ratio (SNR) and finer spatial resolution with lower system complexity. The concept also raises significant technical challenges. The spacecraft formation has great effect on radar performance, such as spatial resolution, the angle of two-dimensional (2-D) resolution direction and noise-equivalent sigma zero (NESZ). This paper establishes the relationship between the imaging performance and the formation parameters. Then, a novel design method of spacecraft formation is presented, identifying the principal formation design choices and constraints. Finally, simulation results are provided for typical observational tasks, to verify the effectiveness of the proposed method.
关键词： imaging performance,spacecraft formation,bistatic SAR,geosynchronous
更新于2025-09-23 15:23:52
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[IEEE IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Valencia (2018.7.22-2018.7.27)] IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Focusing of Spaceborne Bistatic SAR Data Based on Time-Domain Perturbation
摘要： Spaceborne bistatic synthetic aperture radar (BiSAR) system with an inclined geosynchronous (GEO) illuminator and a low-earth-orbit (LEO) receiver is capable of providing higher signal-to-noise ratio (SNR), finer resolution and vast area of surveillance. However, spatial-variant characteristics of the echo signal caused by the complex bistatic formation raise technical challenges in data focusing. To address the issue, an improved chirp scaling (CS) algorithm based on time-domain perturbation is proposed. Firstly, the signal model of GEO-LEO bistatic SAR is derived based on the geometry. Then, two-dimension (2-D) perturbation functions are employed to correct the spatial-variant characteristics of the echo signal. Finally, the phase compensation functions are generated to compensate for the residual phase. The proposed algorithm is able to implement wide-swath and high-resolution imaging. Simulation results of point targets show the validity of the presented method.
关键词： chirp scaling,spatial-variant,imaging,bistatic SAR,time-domain perturbation
更新于2025-09-23 15:22:29
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[IEEE 2018 IEEE International Conference on RFID Technology & Application (RFID-TA) - Macau, Macao (2018.9.26-2018.9.28)] 2018 IEEE International Conference on RFID Technology & Application (RFID-TA) - Research on Fast Algorithm for General Bistatic SAR Raw Signal
摘要： A fast algorithm for general bistatic synthetic aperture radar (SAR) raw signal based on two-dimensional frequency domain is proposed. The SAR echo signal model is established by the algorithm, the accurate expression of two-dimensional frequency domain for the bistatic SAR echo signal are deduced with series reversion. Simulating large range and azimuth coupling, the accurate computation of echo signal is realized and the complexity of the algorithm is analyzed. The simulation results show that the simulation speed of SAR echo is greatly improved under the premise of ensuring the high phase accuracy, and the validity of the algorithm is proved.
关键词： synthetic aperture radar (SAR),bistatic,series reversion,echo simulation
更新于2025-09-23 15:22:29
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[IEEE IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Valencia (2018.7.22-2018.7.27)] IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Spaceborne Bistatic SAR Scene Simulation
摘要： Augmenting traditional spaceborne SAR sensors with additional receive-only satellites in close formation enhances the observation space, allowing for single-pass interferometry in along- and/or across-track with flexible baselines and the potential to build tomographic stacks with reduced temporal decorrelation properties. The feasibility of such add-ons is presently investigated by ESA and other national space agencies and for a variety of master satellites operating from X- to L-band. This paper presents a simulation framework for complete scenes dedicated specifically to the analysis of the additional technical requirements imposed by the bistatic SAR imaging geometry with relatively large along-track separation of illuminating master/chief and the receive-only slaves/deputies.
关键词： synchronisation,bistatic synthetic aperture radar
更新于2025-09-23 15:22:29
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[IEEE IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Valencia (2018.7.22-2018.7.27)] IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Feasibility of Passive Bistatic Geosynchronous Radar Using Comsat Transmissions
摘要： Communications satellites in geosynchronous orbit are increasingly broadcasting digital signals with high bandwidth and high power. These signals are in principle well-suited to radar imaging and the study presented here is an initial feasibility study for a passive bistatic synthetic aperture radar using satellites in geosynchronous orbit (GEO). The persistent viewing possible from GEO could enable important new applications. The mission concept is outlined and studies of the available signal formats identify digital TV broadcasts in Ku-band as most suitable for radar imaging. The additional space hardware required is a dedicated receive channel, which could be implemented as a hosted payload at modest cost. Our findings so far suggest that the mission concept is feasible for coarse spatial resolution images and that it could therefore provide a low-cost technology demonstration of geosynchronous radar.
关键词： passive,comsat,bistatic,geosynchronous,radar
更新于2025-09-23 15:22:29
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Bistatic SAR: Forecasting Spatial Resolution
摘要： This paper derives closed form expressions for bistatic synthetic aperture radar spatial resolution of a generalized system from the k-space or the wavenumber domain. These spatial resolution equations have not previously appeared in the literature. From these equations, significant resolution is found in both range and cross-range forecasting a forward-scatter bistatic synthetic aperture radar image when the elevation angles of each bistatic platform are significantly different. Simulation and lab tests demonstrated the forward scatter resolution.
关键词： image resolution,synthetic aperture radar,radar remote sensing,spatial resolution,radar imaging,bistatic radar,microwave imaging
更新于2025-09-23 15:22:29
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[IEEE IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Valencia (2018.7.22-2018.7.27)] IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Repeat-Pass Spaceborne Transmitter-Stationary Receiver Bistatic Sar Interferometry - First Results
摘要： This paper presents the first results obtained by repeat-pass bistatic synthetic aperture radar (SAR) interferometry using a fixed C-band ground-based receiver and the Sentinel-1A/B satellites as transmitters of opportunity. The methodology developed to obtain repeat-pass bistatic SAR interferograms uses as input a stack of range compressed bistatic acquisition data and mainly consists in the following stages: raw interferograms computation on a two-dimensional grid in ground geometry, atmospheric phase screen removal and topographic phase compensation. The displacements of a high-rise building were estimated using two stacks of bistatic SAR images acquired between April-June 2017 over an area of Bucharest city, Romania.
关键词： Interferometry,Bistatic SAR,Repeat-pass
更新于2025-09-23 15:22:29
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[IEEE IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Valencia (2018.7.22-2018.7.27)] IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Relationship Between Bistatic Radar Scattering Cross Sections and GPS Reflectometry Delay-Doppler Maps Over Vegetated Land in Support of Soil Moisture Retrieval
摘要： This paper presents the application of a coherent bistatic radar scattering model from vegetated terrains and the extension of the model to circularly polarized incident wave cases for GNSS signals. It will then present an analysis relating the bistatic scattering Radar Cross Sections (RCS) of vegetated land cover to the customary Delay Doppler Maps (DDMs) resulting, e.g., from GNSS reflectometry (GNSS-R) observations. This step is key in being able to use GNSS-R data in soil moisture retrieval algorithms. While some analyses exist for this purpose for scattering from sea surface, such analysis has not been carried out specifically for vegetated land surface. The proposed model and methods are envisioned to be applied to the airborne GNSS Reflectometer Instrument for Bistatic SAR (GRIBSAR) project currently under development, as well as to the CYGNSS mission.
关键词： GRIBSAR,Coherent bistatic radar scattering model,GNSS-R,RCS,Delay Doppler Map
更新于2025-09-23 15:22:29