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With the development of hardware, the detection of ground moving targets with single-channel synthetic aperture radar (SAR) can be achieved by a relatively higher pulse repetition frequency (PRF). This high PRF can bring adequate amount of information, but it also expands the non-clutter spectrum which affects the precision of the real-time detection by the Doppler spectrum shifting methods. In order...
Synthetic aperture radar (SAR) is a kind of coherent imaging system that produces a random pattern, named speckle, which degrades the quality of SAR images and affects their further application seriously. Therefore how to restore SAR image from speckled one has become a necessary step in post-processing of image. In this paper, a new despeckling algorithm is presented based on wavelet transform using...
In this paper we combine advanced STAP algorithms and concepts for adaptive guard channels with subarrayed planar arrays together with the theoretical results available in the field of adaptive detection (GLRT, AMF, ACE tests). The aim is to define a robust adaptive sidelobe blanking detector against combined impulse and CW interference as well as strong clutter discretes. For the selection of the...
A demonstration of multiple-input multiple-output over-the-horizon radar is presented. Transmitter signal beam- forming on a multi-element array has been created, not conventionally before transmission at the transmitter facility, but, after radar signal transmission, skywave propagation, target scattering, return signal propagation, and reception using an over-the-horizon radar receiver. Transmitter...
In this paper the STAP detector based on the low-rank approximation of the normalized adaptive matched filter (LRNAMF) is investigated for its false alarm probability (FAP) performance. An exact formula for the FAP of the LRNAMF detector is derived using the g-method estimator [4]. The non-CFAR behavior of this detector is shown via simulations using different models for the clutter-plus-noise covariance...
This paper presents the achievements of the flight campaign of the SOSTAR-X (stand-off surveillance and target acquisition radar) program relevant to the ground moving target indicator (GMTI) modes designed for wide area surveillance and fast sector scan. The SOSTAR-X is the European technologic demonstrator for an advanced AESA (Active Electronically Steered Antenna) airborne radar sensor. This program...
This paper describes work carried out at QinetiQ to demonstrate real-time operation of space-time adaptive processing (RTSTAP) for airborne phased array radar, in a laboratory environment. RTSTAP processing is performed using field programmable gate array (FPGA) hardware and controlled via a MATLABcopy graphical user interface. The FPGA hardware is connected to the PACER (phased array concepts evaluation...
The integration of current traffic monitoring operational systems in the field of maritime surveillance is widely acknowledged as a key requirement for borders control and illegal trafficking prevention. In this paper, an overview of the satellite-extended-vessel traffic service (SEV) system for in-situ and earth observation (EO) data association is presented. The description of the cognitive data...
In this paper a MAP estimator is derived for target position estimation in high resolution radars where the events of backscatters, i.e., reflections, from extended targets and clutter are modeled as non-homogenous Poisson process. Performance of the proposed MAP estimator has been compared to that of the maximum likelihood estimator for the same model and also to that of the most commonly used peak...
The design of transmit waveforms is critical to the performance of a radar system. Traditionally, pulsed and wideband chirp transmit waveforms are used. Our focus here is on the design of waveforms matched to extended targets. In the literature, optimum transmit waveform design in additive receiver noise has been investigated both from SNR maximization and information-theoretic approaches. In this...
In this paper, we study the resolution properties of linear FM pulses (chirps). Based on the ambiguity surface properties of chirp pulses, we propose a transmission strategy and a processing algorithm that has better delay-Doppler resolution than traditional matched filtering. It is shown that the improvement in resolution is accompanied by a small degradation in detection performance.
The following topics are dealt with: airborne radar; MTI & ECCM; waveform design and synthesis; advanced interferometric SAR technique; active phased array; data fusion & KBS; spaceborne SAR and meteorology.
This paper concerns the joint multi-frame sequential target detection and track estimation in early-warning radar surveillance systems. The rationale for applying sequential procedures in such a scenario is that they promise a sensitivity increase of the sensor or, alternatively, a reduction in the time needed to take a decision. Unlike previous works on sequential radar detection, the attention is...
Current weather radar surveillance networks are based upon conventional sensing paradigm of widely-separated, standalone sensing systems using long range radars that operate at wavelengths in 5-10 cm range. Such configuration has limited capability to observe close to the surface of the earth because of the earthpsilas curvature but also has poorer resolution at far ranges. The center for Collaborative...
This paper describes three different continuous wave (CW) radar waveforms which are applied in automotive radar sensors. The radar sensor should be able to detect all objects inside the observation area and to estimate range, radial velocity and azimuth angle simultaneously even in multi target situations. A classical Linear Frequency Modulation (LFM) waveform provides a very high range and velocity...
In this paper we investigate the impact of the presence of an interfering radar on the target direction of arrival (DOA) estimation performed by the reference radar. The DOA estimator is a modified version of the pseudo-monopulse technique that, using adaptive waveform diversity in transmission, can mitigate the dependence of the estimation accuracy on the interfering signal. The importance of using...
The successful deployments of the first spaceborne precipitation radar (TRMM/PR Ku-band, 1997 ) and spaceborne cloud radar (CloudSat/CPR W-band, 2006 ) have demonstrated the feasibility of monitoring atmospheric processes from space with vertical resolutions of a few hundred meters. Future missions being implemented (EarthCARE, W-band ) or envisaged (ACE, Ka- and W-band ) include use of coherent detection...
This paper develops the theory of both optimum and adaptive MIMO radar. It is shown that the optimum MIMO transmit-receiver pair consists of a coupled multidimensional eigensystem and whitening matched filter. Also introduced, is an design procedure for the clutter dominant case. After illustrating theoretical performance gains relative to conventional radar, we address the practical problem of adapting...
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