Precise Calibration of Channel Imbalance for Very High Resolution SAR With Stepped Frequency

Wang, Xiangyu; Murphy, Robert W.; Deng, Yunkai; Wang, Pei; Li, Ning; Yu, Weidong; Wang, Wei

doi:10.1109/tgrs.2017.2688728

Cited by 20 publications

(14 citation statements)

References 19 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…By analyzing Equation (8), the design of the SPRF-SFW with high Doppler tolerance should meet the following two conditions.…”

Section: Waveform Design Methodsmentioning

confidence: 99%

Design and Processing Method for Doppler-Tolerant Stepped-Frequency Waveform Using Staggered PRF

Zhang¹,

Yeh²,

Li³

et al. 2021

Sensors

View full text Add to dashboard Cite

Stepped-frequency waveform may be used to synthesize a wideband signal with several narrow-band pulses and achieve a high-resolution range profile without increasing the instantaneous bandwidth. Nevertheless, the conventional stepped-frequency waveform is Doppler sensitive, which greatly limits its application to moving targets. For this reason, this paper proposes a waveform design method using a staggered pulse repetition frequency to improve the Doppler tolerance effectively. First, a generalized echo model of the stepped-frequency waveform is constructed in order to analyze the Doppler sensitivity. Then, waveform design is carried out in the stepped-frequency waveform by using a staggered pulse repetition frequency so as to eliminate the high-order phase component that is caused by the target’s velocity. Further, the waveform design method is extended to the sparse stepped-frequency waveform, and we also propose corresponding methods for high-resolution range profile synthesis and motion compensation. Finally, experiments with electromagnetic data verify the high Doppler tolerance of the proposed waveform.

show abstract

“…By analyzing Equation (8), the design of the SPRF-SFW with high Doppler tolerance should meet the following two conditions.…”

Section: Waveform Design Methodsmentioning

confidence: 99%

Design and Processing Method for Doppler-Tolerant Stepped-Frequency Waveform Using Staggered PRF

Zhang¹,

Yeh²,

Li³

et al. 2021

Sensors

View full text Add to dashboard Cite

show abstract

“…Here, the calibration signals are used as an example. Table 3 gives the error estimated results of the second sub-chirp relative to the first one by utilizing the internal calibration method proposed in [10], the optimization algorithm proposed in [12], and the presented method. The internal calibration method in [10] is based on the calibration data, and will fail without it.…”

Section: B Ground-based Real Datamentioning

confidence: 99%

“…The internal calibration method in [10] is based on the calibration data, and will fail without it. The optimization algorithm in [12] requires multiple iteration, therefore the computation load is heavy. Our method is independent on any additional information, and it only requires the overlapped spectra between adjacent sub-band signals which can be satisfied by most systems.…”

Section: B Ground-based Real Datamentioning

confidence: 99%

“…In [11], it points out that there is a possibility to design the optimal compression filter by obtaining the difference phase from the interferogram of the sub-band signals, however, neither the implementation procedures, nor the confirmation is presented. A error calibration strategy is proposed in [12], where three calibration loops are utilized to compensate the channel imbalance first, and then the residual errors are calibrated by solving the optimization problems. Since the search operation is inevitable, the computational load is relatively heavy.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

A Novel Echo-Based Error Estimation and Ripple Elimination Method for Stepped Frequency Chirp SAR Signal

2019

View full text Add to dashboard Cite

Stepped frequency chirp signals are widely used in synthetic aperture radar (SAR) systems to obtain high range resolution images. In practice, however, unavoidable sub-band errors caused by system and propagation errors degrade the performance of the synthetic signals. In this paper, a novel method is proposed to estimate the sub-band errors based on the overlapped spectra between adjacent sub-band signals, while most of the other methods are relied on some additional information. Besides, a filter for eliminating the ripples caused by the overlapped spectra is presented. Finally, the simulation and ground-based real data validate the method.INDEX TERMS Synthetic aperture radar (SAR), high range resolution, stepped frequency, error estimation.

show abstract

“…This limitation of text description is easy to produce error. People need to perceive the content of the video by directly watching the real picture of the video and find the target they are interested in [8]. The amount of video data is large and there are many redundant information.…”

Section: Introductionmentioning

confidence: 99%

Key Frame Extraction Algorithm of Motion Video Based on Priori

Zhong

Zhang

et al. 2020

IEEE Access

View full text Add to dashboard Cite

This work was supported by China University of Geosciences (Beijing) undergraduate education quality improvement plan off campus practice base construction project, college students outdoor sports practice teaching base, project number: SJJD202006 ABSTRACT Key frame extraction technology is one of the core technologies of content-based video retrieval. For video types with complex content, various scenes, and rich actions, the performance of existing key frame extraction methods is not ideal. Based on the Visual Geometry Group (VGG), this paper proposes an image saliency extraction model assisted by deep prior information, and uses a large-scale data set for training on the server to obtain a trained model, and then integrates multiple features. The saliency extraction algorithm is combined with the image saliency extraction model assisted by deep prior information, and a saliency extraction algorithm based on multi-feature fusion and deep prior information is proposed. A new method for extracting key frames of motion video is introduced in detail. Taking into account that sports videos in real applications are susceptible to interference from various factors, resulting in poor picture quality, this article constructs a new visual attention model for moving targets in sports videos, which integrates images. The combination of multiple features of the bottom-level features and the skin color confidence map of the moving target overcomes the problem that a single feature cannot fully express the moving target. Since the processing object in this article is for the moving target in the video of the sports room, the extracted moving target can provide samples for video post-processing. The experimental results show that the proposed key frame extraction algorithm can quickly grasp the pedestrian information in the motion video and provide effective processing samples for the motion target for video post-processing. INDEX TERMS key frame extraction; deep prior information; zero-sample learning; motion video; visual attention model.

show abstract

Precise Calibration of Channel Imbalance for Very High Resolution SAR With Stepped Frequency

Cited by 20 publications

References 19 publications

Design and Processing Method for Doppler-Tolerant Stepped-Frequency Waveform Using Staggered PRF

Design and Processing Method for Doppler-Tolerant Stepped-Frequency Waveform Using Staggered PRF

A Novel Echo-Based Error Estimation and Ripple Elimination Method for Stepped Frequency Chirp SAR Signal

Key Frame Extraction Algorithm of Motion Video Based on Priori

Contact Info

Product

Resources

About