The biggest challenge for GEO SAR imaging is to compensate the doppler parameter space-variance properly. The problem of velocity space-variance becomes severe in GEO SAR due to the effect of earth rotation and large ...
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ISBN:
(纸本)9781849199940
The biggest challenge for GEO SAR imaging is to compensate the doppler parameter space-variance properly. The problem of velocity space-variance becomes severe in GEO SAR due to the effect of earth rotation and large imaging area. In addition, the direction of velocity spacevariance is very difficult to determine in Equator due to th e very comple x g eo metry re lations h ip among s atellite motion, earth rotation and imaging scene, thus making it difficult to be compensated. These problems can't be solved with present GEO SAR imaging algorithm. This literature proposes an improved secondary range compression (SRC) algorithm. The GEO SAR signal model is obtained firstly. The effects of velocity space-variance on each term of GEO SAR signal two-dimension spectrum are analyzed. Then, the velocity space-variance is described based on a velocity model, the effect of velocity space-variance is compensated by means of adaptive phase compensation processing. Finally, the correctness of this method is proved through tagret points simulation.
An accurate non-contact amplitude retrieval of the periodic movement is proposed in this paper. Firstly, the backscattered signal of a vibrational target can be expanded as a series of harmonics whose amplitudes are d...
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ISBN:
(纸本)9781785610387
An accurate non-contact amplitude retrieval of the periodic movement is proposed in this paper. Firstly, the backscattered signal of a vibrational target can be expanded as a series of harmonics whose amplitudes are determined by the vibration amplitude. Then, based on the least squares estimation, all the available harmonics are utilized to suppress the influence of the signal noise on the vibration measurement, so as to improve the accuracy of vibration amplitude retrieval. Finally, the Monte Carlo simulation is performed to validate the effectiveness in the case of low signal-to-noise ratio (-9dB). Accuracy of the new method in different cases of signal-to-noise ratio is also obtained. In addition, the real experimental data acquired by a 100GHz millimeter radar is used to test the performance of the proposed method, associated with a calibrator of vibration. In the experiment, a calibrator of vibration is 30m away from the radar. The results show the proposed method has better accuracy than the ones in the case of only one harmonic pair is used.
This paper proposes a novel subsidence monitoring method. The method utilizes multi Global Navigation Satellite System (GNSS) as illuminators, a receiver employed in reference station and a transponder set in the regi...
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ISBN:
(纸本)9781785610387
This paper proposes a novel subsidence monitoring method. The method utilizes multi Global Navigation Satellite System (GNSS) as illuminators, a receiver employed in reference station and a transponder set in the region of interest as a measurement station to construct the realtime subsidence monitoring system. Exploiting the commonness of the errors in both the reference station and the measurement one, extending the principle of traditional differential GNSS (DGNSS) to a radar-transponder counterpart, a low cost and high accuracy system with 3 dimensional deformations estimation ability can be realized. Simulation is conducted to analyze the performance and validate the proposed method. The result shows that the proposed method is able to achieve sub-centimeter accuracy in short coherence time, promising its potential application in some security fields such as the high-speed railway roadbed subsidence monitoring.
In this paper, a novel imaging algorithm tailored for GB-SAR data is proposed. The characteristics of GB-SAR data are firstly analyzed, and then a signal model (after range compression) is analytically built up. Accor...
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ISBN:
(纸本)9781849199940
In this paper, a novel imaging algorithm tailored for GB-SAR data is proposed. The characteristics of GB-SAR data are firstly analyzed, and then a signal model (after range compression) is analytically built up. According to this model, our imaging algorithm, based on keystone formatting and range-Doppler domain subblock division, is then put forward, its azimuth focusing is essentially achieved through a space-variant dechirp operation. This algorithm can be widely applied to near-field and far-field as well as wide view angle GB-SAR data sets. Moreover, the computational cost of this algorithm is quite low. The image is formatted in a polar-like coordinate which is well fit for GB-SAR data. The algorithm is extensively validated both with numerical simulations and real GB-SAR data.
In this paper, an FPGA-based moving object detection and tracking system is introduced for image processing application. The algorithms presented include object detection based on dynamic background difference, kalman...
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ISBN:
(纸本)9781849199940
In this paper, an FPGA-based moving object detection and tracking system is introduced for image processing application. The algorithms presented include object detection based on dynamic background difference, kalman filter for object tracking. The target device for the implementation is a Xilinx Zynq-7000 FPGA. The use of ARM dual core processor, NEON vector coprocessor unit and coprocessing IP peripherals generated by vivado HLS aim to improve the data processing ability of the system. In the dynamic background, the system realized accurate detection and tracking of moving objects in real-time.
With the rapid development of satellite-based signal processing technologies comes the widespread deployment of SAR image processing systems in spaceborne applications, many of which are implemented as FPGA-based syst...
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ISBN:
(纸本)9781849199940
With the rapid development of satellite-based signal processing technologies comes the widespread deployment of SAR image processing systems in spaceborne applications, many of which are implemented as FPGA-based systems thanks to the introduction of modern programmable devices with high capacity and complexity. However, as raw data of SAR satellites grow in size and bandwidth the effective implementation and especially the efficient system verification are emerging as the bottleneck in the development of FPGA-based SAR image processing systems. This paper proposes methods in the verification phase of FPGA-based SAR processing system development which on one hand increases the verification speed during simulations and on the other addresses the hardware/Matlab mismatch issue through comparison of floating point numbers on grounds of error analysis from a mathematical approach. Actual development process indicate that the proposed methods guarantee quick design convergence, and test results on real hardware confirm that the SAR image processing system offers acceptable quality of image output.
This paper concentrates on the hardware implementation of CORDIC algorithm for computing inverse trigonometric functions like arcsine and arccosine. We improve the existing algorithm by changing the initial rotating v...
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ISBN:
(纸本)9781849199940
This paper concentrates on the hardware implementation of CORDIC algorithm for computing inverse trigonometric functions like arcsine and arccosine. We improve the existing algorithm by changing the initial rotating vector of the iterations and modifying the judging condition of rotation direction. Due to the improvement, two iterations are saved and the drawback of the previous algorithm is corrected. In contrasting with the previous implementation, the improved algorithm consumes less hardware resources and its computing results are more accuracy.
Due to the existence of the large scale matrix transposition, the memory bandwidth becomes the bottleneck of the real-timeprocessing in spaceborne SAR imaging. The paper reports a preliminary study result of the memo...
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ISBN:
(纸本)9781849199940
Due to the existence of the large scale matrix transposition, the memory bandwidth becomes the bottleneck of the real-timeprocessing in spaceborne SAR imaging. The paper reports a preliminary study result of the memory architecture in the spaceborne SAR imaging system. It consists of algorithm summarizations, implementation difficulty discussions and processing requirement analysis. Then, a new memory architecture is being proposed to improve memory access efficiency and its implementation is specified. Finally, results of different methods are compared and imaging results validates the presented memory architecture.
This paper presents a method of the implementation of a verification platform. The platform is applied to an ASIC chip designed for the key algorithm of SAR signal processing. The design is a complicated process and t...
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ISBN:
(纸本)9781849199940
This paper presents a method of the implementation of a verification platform. The platform is applied to an ASIC chip designed for the key algorithm of SAR signal processing. The design is a complicated process and the chip function is computationally burdensome, thus the verification is difficult. Balancing the competing demands for efficiency, quality, time and cost, the verification platform is carefully designed using the Verilog language, with Synopsys VCS-MX2009 adopted. The experimental results show that the design errors of timing and anti-protocols have been exactly checked out and the verification coverage reaches 100% at last. The platform possesses satisfying characteristics such as high performance, fine configurability, flexibility and expansibility.
This paper proposes and implements the relative radiometric correction for remote sensing images based on Vivado HLS with FPGA. This design not only simplifies the development process, but successfully achieved the pu...
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ISBN:
(纸本)9781849199940
This paper proposes and implements the relative radiometric correction for remote sensing images based on Vivado HLS with FPGA. This design not only simplifies the development process, but successfully achieved the purpose of improving the image quality of remote sensing image. Firstly, this paper gives a brief analysis on the radiometric correction algorithm based on histogram matching correction, and then using C to complete the hardware development of FPGA by HLS. The results validate the feasibility of histogram correction based on HLS.
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