IEEE National Radar Conference - Proceedings

Description

  • ISSN
    1097-5659

Publications in this journal

  • Conference Proceeding: Measurements of bistatic radar sea clutter
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    ABSTRACT: Bistatic radar is a technique of considerable potential importance and interest. Despite this, current understanding of the properties of bistatic clutter, and in particular, bistatic sea clutter, is limited at best. We present some results of a recent trials campaign to gather bistatic sea clutter data, and to analyse the data in order to develop models to represent bistatic radar sea clutter. The results indicate that the shape parameter of the compound K distribution model fitted to the data tends to be higher for the bistatic clutter than for the equivalent monostatic clutter. This suggests that a bistatic geometry may allow a lower detection threshold for a given probability of false alarm, and hence give improved detection performance of weak targets against a clutter background compared to the conventional monostatic geometry.
    Radar Conference (RADAR), 2011 IEEE; 06/2011
  • Conference Proceeding: False alarm probability estimation for Compressive Sensing radar
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    ABSTRACT: In this paper false alarm probability (FAP) estimation of a radar using Compressive Sensing (CS) in the frequency domain is investigated. Compressive Sensing is a recently proposed technique which allows reconstruction of sparse signal from sub-Nyquist rate measurements. The estimation of the FAP is based on an empirical model derived from simulations of the probability density function (pdf) of the noise samples reconstructed using the basis pursuit denoising (BPDN) algorithm. During simulations noise levels were assumed to be known; in practice noise or clutter power is not known a priori, and must be estimated from the radar data. As in radar applications it is desirable to have a Constant False Alarm Rate (CFAR), the aim here is to understand the statistical behavior of noise after CS reconstruction for designing CFAR radar detection schemes.
    Radar Conference (RADAR), 2011 IEEE; 06/2011
  • Conference Proceeding: A low-complexity sparsity-based multi-target tracking algorithm for urban environments
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    ABSTRACT: In this paper, we propose a low-complexity sparsity based multi-target tracking algorithm. We develop a finite dimensional representation of the received signal when the radar is operating in an urban environment. The dimensionality of the representation denotes the extra degrees of freedom that an urban environment offers. We employ spread-spectrum signaling to exploit the full diversity offered by the environment. We then develop a block-sparse measurement model by discretizing the delay-Doppler plane and prove that the dictionary of the block sparse model exhibits a special structure under spread-spectrum signaling. This structure enables an efficient support recovery of the sparse vector, by projecting the measurement vector on the row space of the dictionary. Numerical simulations show that our tracking procedure takes significantly less time, while giving good tracking performance.
    Radar Conference (RADAR), 2011 IEEE; 06/2011
  • Conference Proceeding: A Multistatic Circular Synthethic Aperture Radar for small Object Detection
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    ABSTRACT: This paper introduces a ground-based Multistatic Circular Synthetic Aperture Radar (MuCSAR) used to detect small objects on the ground. The received signals have been modelled and the system prototype has been developed. The proposed signal processing is also described. An experimental investigation for Foreign Object Detection application has been analysed.
    Radar Conference (RADAR), 2011 IEEE; 06/2011
  • Conference Proceeding: Wind Turbine radar signature characterization by laboratory measurements
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    ABSTRACT: WTC (Wind Turbine Clutter) is clutter caused by wind turbines in the radar vicinity. As the power capacity of a single wind turbine increases, its size also increases dramatically. As a result, wind turbines not only block the radar beam, causing shadowing effects, but also create spectral contaminations due to the blade rotation. As a recently recognized type of clutter, WTC radar signatures need to be fully studied so that better solutions can be found for mitigation from radar data. Field measurements have difficulties controlling wind turbine motions, but laboratory measurements have full control of the wind turbine model, radar and EM environment. For such a purpose, the wind turbine-radar interaction was emulated in the laboratory, with full controllability of a scaled wind turbine model in an anechoic chamber. A scatterometer was made to emulate the actual radar functions. The measured wind turbine model Radar Cross Section (RCS) fluctuation caused by blade rotation and yaw movement will be shown. The Physical Optics (PO) EM solver was applied to simulate the scaled model RCS. The spectrogram and related features will also be analyzed.
    Radar Conference (RADAR), 2011 IEEE; 06/2011
  • Conference Proceeding: Radar tomography using Doppler-based projections
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    ABSTRACT: Image reconstruction using tomography is based on inverse filtering a series of projections, collected at angular positions surrounding an object or scene, where the form of the projection is derived from the measurement geometry (monostatic/bistatic, point/plane transducer/sensor) as well as the probing phenomenology. Quality image reconstruction requires that sensors are positioned to adequately sample target/scene Fourier space. In a remote sensing application this is done by sequentially positioning a limited number of sensors in the half-space above the target region. Typically projections are formed by integration along the locus of points of constant delay (the line integration path). Such projections are defined purely spatially. In this paper we define and evaluate projections that are derived from the Doppler relationships of the measurement geometry and temporal integration. The circular aperture is subdivided into overlapping SAR subapertures. This has the effect of creating fan beam-like projections, in 2D the projections linearly diverge from the source point with the formation of an image referenced to scene center effects the receiving array. Images are reconstructed using back projection filtering. The Doppler-based phenomenology is demonstrated and point spread function(s) generated. The advantage of this technique is the production of high resolution 2D, and extendable to 3D, images using very low bandwidth. This is applicable to low frequency waveforms operating in spectrum challenged environments or where communications bandwidths do not support wideband data transfer.
    Radar Conference (RADAR), 2011 IEEE; 06/2011
  • Conference Proceeding: Refocussing of moving targets in SAR images based on inversion mapping and ISAR processing
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    ABSTRACT: Moving target often appear defocussed in SAR images due to their relative motion with respect to the SAR center scene. In several applications that require target classification and/or recognition an unfocussed image of a target would likely lead to misclassification, therefore decreasing classification performances. In this paper, the authors present a new method for refocussing moving targets starting from formed Single Look Complex (SLC) SAR images. Results obtained by applying the proposed technique to Cosmo Skymed (CSK) SLC SAR images show its effectiveness.
    Radar Conference (RADAR), 2011 IEEE; 06/2011
  • Conference Proceeding: Range-ambiguous clutter suppression with Pulse-diverse waveforms
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    ABSTRACT: Conventional pulse-Doppler waveforms are the standard for radar detection in clutter due to their inherent robustness, especially to extended-range ambiguous clutter. The attendant drawbacks include coherent ambiguities and blind zones in range and/or Doppler, which require multiple coherent precessing intervals to resolve. Pulse-diverse waveforms, using techniques such as phase coding and nonuniform time offsets, can mitigate these drawbacks but at the cost of a significant reduction in clutter suppression using matched filtering. It is shown here that receive filtering optimized on a per-interval or per-range/Doppler-cell basis can provide these waveforms with clutter suppression over multiple range intervals, at the cost of significantly increased computation. Several examples illustrate the tradeoffs between different types of pulse diversity.
    Radar Conference (RADAR), 2011 IEEE; 06/2011
  • Conference Proceeding: Degree of polarization: theory and applications for weather radar at LDR mode
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    ABSTRACT: We present theoretical and experimental results concerning a polarimetric variable available at LDR mode: the Degree of Polarization. It is demonstrated that it possesses attractive properties in terms of robustness with respect to antenna cross-channel coupling and to propagation due to coherent cross-polarization upon forward scattering.
    Radar Conference (RADAR), 2011 IEEE; 06/2011
  • Conference Proceeding: Exploitation of Cosmo SkyMed SAR images for maritime traffic surveillance
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    ABSTRACT: Moving targets often appear defocussed in SAR images due to their relative motion with respect to the stationary scene. In several applications that require target classification and/or recognition an unfocussed image of a target would likely lead to misclassification, therefore decreasing classification performance. In this paper the authors present a new tool for automatically detecting and refocussing maritime moving targets starting from satellite Single Look Complex (SLC) SAR images. Preliminary results obtained by applying the proposed technique to Cosmo SkyMed (CSK) SLC SAR images show the effectiveness of the proposed approach.
    Radar Conference (RADAR), 2011 IEEE; 06/2011
  • Conference Proceeding: Localizations of targets inside enclosed structures with a single sensor
    Radar Conference (RADAR), 2011 IEEE; 05/2011
  • Conference Proceeding: Agent based multifunction radar surveillance control
    Radar Conference (RADAR); 01/2011
  • Conference Proceeding: Strategies for the calibration of an array of patch antennas in passive bistatic SAR imaging
    Radar Conference (RADAR), 2011 IEEE; 01/2011
  • Conference Proceeding: The reflection of electromagnetic field by body tissue in the UWB frequency range
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    ABSTRACT: Radar systems have been found in several electromagnetic applications such as medical image capture and editing. In this paper, we study the electromagnetic interaction with human body in the UWB frequency range. In an attempt to compute the reflection and transmission wave by each layer of the human body, we will apply an analytic method. Our solution consists in recursion expression that discards the mutual influence between human body layers to estimate the echo of each layer which involves human body of a radar incident impulsion. With this result we are capable to compute reflected and transmitted electromagnetic wave by each layer of human tissues in an attempt to capture image of human body structure.
    Radar Conference, 2010 IEEE; 06/2010
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    Conference Proceeding: A robust neural network based pulse radar detection for weak signals
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    ABSTRACT: In this paper we develop a neural network capable of detecting targets with weak echoes in a pulse radar. This is possible as the network is designed as a pattern classifier (in contrast to earlier work) together with a suitable but simple pre-processing of the returns. We demonstrate through simulations that such a network exhibits better range resolution and noise tolerance when compared to previous work based on neural networks. In addition, we examine the Doppler tolerance and the overall robustness of the trained network.
    Radar Conference, 2010 IEEE; 06/2010
  • Conference Proceeding: Spotlight-mode synthetic aperture radar processing for high-resolution lunar mapping
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    ABSTRACT: During the 2008-2009 year, the Goldstone Solar System Radar was upgraded to support radar mapping of the lunar poles at 4 m resolution. The finer resolution of the new system and the accompanying migration through resolution cells called for spotlight, rather than delay-Doppler, imaging techniques. A new pre-processing system supports fast-time Doppler removal and motion compensation to a point. Two spotlight imaging techniques which compensate for phase errors due to (i) out of focus-plane motion of the radar and (ii) local topography, have been implemented and tested. One is based on the polar format algorithm followed by a unique autofocus technique, the other is a full bistatic time-domain backprojection technique. The processing system yields imagery of the specified resolution. Products enabled by this new system include topographic mapping through radar interferometry, and change detection techniques (amplitude and coherent change) for geolocation of the NASA LCROSS mission impact site.
    Radar Conference, 2010 IEEE; 06/2010
  • Conference Proceeding: Design alternatives for Foliage Penetration SAR ultra wideband waveforms
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    ABSTRACT: Foliage Penetration SAR has achieved significant operational attention from both military and civilian applications. To achieve the spatial resolution desired, the waveform must occupy fractional bandwidths near 100 percent, and integration angles on the order of π/2. Both design objectives are classified as ultra-wideband, and require special constraints to allow operation in the crowded radio frequency spectrum. This effort examines the SAR waveform design approaches, given the recent advances in digital waveform synthesis, to satisfy frequency allocation constraints.
    Radar Conference, 2010 IEEE; 06/2010
  • Conference Proceeding: Processing-based tuner gain correction in a wideband multi-channel receiver
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    ABSTRACT: Modern radar systems often capitalize on advanced radio frequency components in the receiver front end to include wideband tuners and amplifiers, highly stable local oscillators, and high-speed analog-to-digital converters. Yet, technology demonstrators often emphasize either the hardware or the processing algorithm rather than the end-to-end system. This paper presents the hardware characterization of tuner-gain mismatch in a wideband multi-channel array and the subsequent signal processing calibration model. The gain model is empirically found to follow a T-distribution and is used to balance the amplitude across the tuners as part of the processing for time-frequency-beamforming. Phase is also shown to be the critical factor to completely correcting phase mismatch. Here, we present details of the wideband receiver front-end and the signal processing backend.
    Radar Conference, 2010 IEEE; 06/2010
  • Conference Proceeding: Simulated SAR system for maritime target imaging using a PO-based approach
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    ABSTRACT: This contribution deals with the simulation of a SAR system for imaging complex scenes made of targets (boats) over a sea surface. A physical optics and method of equivalent currents-based method is investigated to model the complex targets in its maritime environment. The considered global radar radio-link model gives full polarimetric information. In order to validate some parts of the model and to illustrate the proposed global SAR model, some simulations are proposed.
    Radar Conference, 2010 IEEE; 06/2010

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