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Regularization technology can be utilized to improve the azimuth resolution for forward-looking scanning radar (FLSR). Among various regularization methods, L1 norm constrained method is usually adopted for its strong ability in resolving the sparse targets. Nevertheless, the solution of L1-norm constrained regularization method (L1-CRM) is sensitive to noise and the iterations would quickly diverge...
With the rapid advancement of autonomous driving and vehicular communication technology, intelligent intersection management has shown great promise in improving transportation efficiency. In a typical intelligent intersection, an intersection manager communicates with autonomous vehicles wirelessly and schedules their crossing of the intersection. Previous system designs, however, do not address...
Fast Factorized Back-projection (FFBP) is a new way to fix the high computation problem in Back-projection (BP) but it still keeps high-resolution and strong adaptability in synthetic aperture radar (SAR). However, Applying conventional autofocus methods to both BP and FFBP requires a special consideration. In this letter, we present a new method to solve the phase error problem. We establish a evaluation...
The micro-Doppler induced by micro-motion in radar target represents an important characteristic made available for target recognition, which is usually manifest a sinusoid in the time-frequency (T-F) domain. Inverse Radon transform has been validated as an effective sinusoid detection method. Considered on the condition that multiple sinusoids existed in the T-F plane especially one is weaker relatively,...
The Radio Frequency Identification (RFID) is a rapidly developing technology with growing applications in several fields. One of the key applications is the localisation of tagged objects using signal phase difference information via dual-frequency technology. In this application, unwrapping signal phases to acquire the range between the reader and RFID tag is the major issue that has typically been...
Increasingly more software-based applications are being developed and deployed in modern vehicles. As a result, the extensibility of a system design has become an important issue in order to accommodate more future applications and update of existing ones on one hand and reduce the effort and cost of re-design, test and validation on the other. In this paper, we discuss the extensibility-driven design...
Convergence speed is quite important for a iterative superresolution algorithm, especially in real time processing. A vector extrapolation acceleration maximum a posteriori (VEAMAP) superresoltuion algorithm is proposed in this paper. In the algorithm a predicted point is made before initial multiplicative iteration and this can make the iterations go faster along the convergence path. As the prediction...
Nonhomogeneous clutter environments such as multiple target situation and clutter edge environment can dramatically affect the radar signal detection performance. In order to solve the problem, this paper proposes an automatic censored CFAR detector based on ordered data difference with non-coherent integration. The proposed CFAR detector does not require any prior information about the background...
Deconvolution techniques can be utilized to realize angular resolution enhancement for real-beam scanning radar (RBSR). However, most deconvolution algorithms are sensitive to noise and time consuming. In this paper, an accelerated iterative shrinkage/thresholding (AIST) algorithm is proposed to overcome these disadvantages. AIST is developed from iterative shrinkage/thresholding (IST) algorithm which...
This paper proposes a novel registration method for optical and SAR images which is based on straight line features and mutual information. Firstly, different edge detectors are employed to detect the line segments in both optical and SAR images respectively. Then, through the Hough transform and a straight line fitting and filtration method, the main straight lines of each image are extracted and...
This paper deals with the problem of estimating the directions of arrival (DOAs) in airborne forward-looking radar imaging, by joint processing the sum and difference channel data. It is known that the monopulse system uses two channels, the sum and the difference, to estimate the target DOA. However, it fails to work when multiple targets are located within the beamwidth. Aiming at this problem,...
For bistatic forward-looking synthetic aperture radar (BFSAR), motion errors induce two adverse effects on the echo, namely, azimuth phase error and residual range cell migration (RCM). Under the presumption that residual RCM is within a range resolution cell, residual RCM can be neglected, and azimuth phase error can be compensated utilizing autofocus methods. However, in the case that residual RCM...
Use of the phase of a signal to measure distance carries an inherent ambiguity. The problem is typically addressed by the use of several different frequencies and the Chinese Remainder Theorem or lattice methods, but these methods result in computational complexity issues. The difficulties are increased by the presence of noise. This paper presents a lattice-based algorithm to resolve phase ambiguity...
Petroleum Cyber-Physical System (CPS) marks the beginning of a new chapter of the oil and gas industry. Combining vast computational power with intelligent Computer Aided Design (CAD) algorithms, petroleum CPS is capable of precisely modeling the flow of fluids over the entire petroleum reservoir and leveraging the massive field data remotely collected at the production wells. It provides field operators...
Along with the spectrum resources increasingly scarce, the Cognitive Radio Networks (CRNs) are drawn more and more attention. Most of existing results on CRNs aim at utilizing wireless spectrum efficiently, however, the network becomes invalid easily due to stochastic activities of Primary Users (PUs). How to sustain the connectivity of the network becomes more and more challenging. In traditional...
Multi-rate systems arise naturally in distributed settings where computing units execute periodically according to their local clocks and communicate among themselves via message passing. We present a systematic way of designing and verifying such systems with the assumption of bounded drift for local clocks and bounded communication latency. First, we capture the system model through an architecture...
The angular superresolution is of great significance for scanning radar in forward-looking imaging. There are many techniques documented in literature to enhance the angular resolution, of which deconvolution method and power spectral density(PSD)methods are favored and attain many interests. In this paper, we focus on analyzing the advantages and challenges of PSD methods in comparison with the deconvolution...
In the imaging processing of translational variant bistatic forward-looking SAR (TV-BFSAR), range cell migration correction (RCMC) is an essential procedure. Based on the azimuth variance property of the range cell migration (RCM), the keystone transformation is used for RCMC in TV-BFSAR. Before the RCMC, the ambiguity correction of the Doppler frequency must be done. However, the motion error makes...
Staggered SAR is an innovative 2-D imaging system utilizing the digital beam-forming (DBF) technique and the continuous variation of pulse repetition frequency (PRF). However, due to the PRF variation, the echo data in the azimuth is non-uniformly sampled. To achieve good imaging quality, it is indispensable to interpolate the data of the staggered SAR to be uniform before further imaging processing...
Most of ever proposed scanning radar angular superresolution algorithms are iterative, but the optimum iterations are difficult to determine. Since the performance of them is related to the signal to-noise ratio (SNR), an accurate SNR estimation would be of great significance to provide reference for assistance of adaptive iteration termination condition analysis. In this paper, a data-aided (DA)...
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