A novel method,referred to as joint multiple subpulses processing,is developed to calibrate the nonideal transfer function of radio frequency front-end and I/Q imbalance in quadrature modulate/demodulate systems simul...A novel method,referred to as joint multiple subpulses processing,is developed to calibrate the nonideal transfer function of radio frequency front-end and I/Q imbalance in quadrature modulate/demodulate systems simultaneously,which frequently occur in wideband Synthetic Aperture Radar(SAR) systems.Based on the time-frequency relation of the chirp signal and the analyses of the channel errors in wideband SAR,joint multiple subpulses processing method is adopted to separate the image frequency component due to the I/Q channel error.Then,the complete description of the channel error is acquired for building the correction function,which is used to correct the radar raw echo in frequency domain.The validity and capability of this method are demonstrated by the experiments of the channel error correction on the high resolution SAR system with the effective bandwidth of 500 MHz.展开更多
This paper presents a method on non-linear correction of broadband LFMCW signal utilizing its relative nonlinear error. The deriving procedure and the results simulated by a computer and tested by a practical system a...This paper presents a method on non-linear correction of broadband LFMCW signal utilizing its relative nonlinear error. The deriving procedure and the results simulated by a computer and tested by a practical system are also introduced. The method has two obvious advantages compared with the previous methods: (1) Correction has no relation with delay time td and sweep bandwidth B; (2) The inherent non-linear error of VCO has no influence on the correction and its last results.展开更多
为了提高地基雷达系统的监测精度,提出一种新的高精度的地基合成孔径雷达干涉GBSAR(Ground Based SAR)监测技术。融合了GBSAR关键技术以及数据处理理论,对影响测量精度的误差项进行了分析研究并从3个方面(雷达系统、数据获取、数据处理...为了提高地基雷达系统的监测精度,提出一种新的高精度的地基合成孔径雷达干涉GBSAR(Ground Based SAR)监测技术。融合了GBSAR关键技术以及数据处理理论,对影响测量精度的误差项进行了分析研究并从3个方面(雷达系统、数据获取、数据处理)具体给出了相应的精度提高措施。基于变形监测系统(IBIS-S)对GBSAR理论研究进行实验验证。实验表明GBSAR技术对于目标体的监测精度较高。最终得到GBSAR技术产生的误差的途径主要源自数据采集的过程。展开更多
基金Supported by the National High-Tech Research and Development Plan of China(No.2007AA120302)
文摘A novel method,referred to as joint multiple subpulses processing,is developed to calibrate the nonideal transfer function of radio frequency front-end and I/Q imbalance in quadrature modulate/demodulate systems simultaneously,which frequently occur in wideband Synthetic Aperture Radar(SAR) systems.Based on the time-frequency relation of the chirp signal and the analyses of the channel errors in wideband SAR,joint multiple subpulses processing method is adopted to separate the image frequency component due to the I/Q channel error.Then,the complete description of the channel error is acquired for building the correction function,which is used to correct the radar raw echo in frequency domain.The validity and capability of this method are demonstrated by the experiments of the channel error correction on the high resolution SAR system with the effective bandwidth of 500 MHz.
文摘This paper presents a method on non-linear correction of broadband LFMCW signal utilizing its relative nonlinear error. The deriving procedure and the results simulated by a computer and tested by a practical system are also introduced. The method has two obvious advantages compared with the previous methods: (1) Correction has no relation with delay time td and sweep bandwidth B; (2) The inherent non-linear error of VCO has no influence on the correction and its last results.
文摘为了提高地基雷达系统的监测精度,提出一种新的高精度的地基合成孔径雷达干涉GBSAR(Ground Based SAR)监测技术。融合了GBSAR关键技术以及数据处理理论,对影响测量精度的误差项进行了分析研究并从3个方面(雷达系统、数据获取、数据处理)具体给出了相应的精度提高措施。基于变形监测系统(IBIS-S)对GBSAR理论研究进行实验验证。实验表明GBSAR技术对于目标体的监测精度较高。最终得到GBSAR技术产生的误差的途径主要源自数据采集的过程。
