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Bells Corners, Canada

Thayaparan T.,Defence RandD Canada Ottawa | Stankovic L.J.,University of Montenegro | Dakovic M.,University of Montenegro | Popovic V.,University of Montenegro
IET Signal Processing | Year: 2010

Radar micro-Doppler (m-D) signatures are of great potential for identifying properties of unknown targets. All the techniques developed for extracting m-D features for the past decade rely primarily on the assumption that the time series of the signal contains at least one oscillation or more during the coherent integration time or imaging time. However, many applications in real-world scenarios involve short duration signals and often require the detection and the estimation of m-D characteristics. Short duration signals may contain only a fraction of an oscillation. In this study, the authors develop two techniques to estimate the m-D parameters from a fraction of the period. In these scenarios, the coherent integration will cover only 1/4 and 1/2 of the oscillation. The performance of the proposed methods are evaluated using both synthetic and experimental data. © 2010 The Institution of Engineering and Technology. Source

Hocking W.K.,Mardoc Inc. | Thayaparan T.,Defence RandD Canada Ottawa | Hocking A.,Mardoc Inc.
IET Signal Processing | Year: 2010

Joint spectral-temporal methods for target detection are not uncommon, but generally involve application of spectral processing on short sub-sections of the original time series. Usually a sliding window is applied, so that the region of truncation slides through the superset. Final analysis and interpretation are usually performed in the spectral domain. Here a new method of temporal-spectral analysis is presented. Truncation is used first in the spectral domain, and then multiple sets of resulting time series are employed for identification purposes. The method is called the ETISTI method ('enhanced truncated interleaved spectral-temporal interferometery'), and is adapted and extended from earlier meteor studies. It uses a combination of band-pass spectral filtering, auto-correlative algorithms and time-series analysis for target detection. It especially utilises long data sets of the order of hundreds to thousands of seconds, in order to improve spectral resolution, but at the same time achieves temporal resolution of the order of seconds. Signal-to-noise levels are determined locally rather than globally, using dynamic auotocovariance methods, thereby allowing adaptive time- and range-dependent noise-level determination, and hence better target discrimination. The method works especially well for accelerating targets, and for targets obscured by ionospheric interference, lightning and intermittent RF noise. © 2010 The Institution of Engineering and Technology. Source

Riddolls R.J.,Defence RandD Canada Ottawa
IEEE National Radar Conference - Proceedings | Year: 2014

An Over-The-Horizon Radar (OTHR) has been deployed near Ottawa, Canada. The radar is aimed northward and collects auroral echoes through line-of-sight propagation and ground echoes from beyond the horizon through ionospheric reflection. These echoes have been resolved in the three spatial dimensions of range, azimuth, and elevation, as well as in the temporal dimension of Doppler. It is shown that the three-dimensional spatial resolving capability is useful for separating the auroral and ground echo components. © 2014 IEEE. Source

Dragosevic M.V.,MD TerraBytes Inc. | Burwash W.,MDA Systems Ltd | Chiu S.,Defence RandD Canada Ottawa
IEEE Transactions on Geoscience and Remote Sensing | Year: 2012

This paper describes in detail several multichannel variants of the famous displaced phase center antenna (DPCA) method suitable for spaceborne multichannel synthetic aperture radar ground moving target indication (GMTI), which has become available through the RADARSAT-2 moving-object detection experiment (MODEX). A flexible signal processing architecture was developed at Defense Research and Development Canada to support R&D work in GMTI and to provide a tool for MODEX system validation. The presented multichannel DPCA method is one of the first algorithms that have been implemented and successfully tested using this architecture. The main objective is to provides a simple, yet effective and robust way to detect ground moving vehicles and to estimate their position and velocity. This work forms a baseline for further advancement in the GMTI area. © 2012 IEEE. Source

Francis R.,University of Western Ontario | Vincent R.,Royal Military College of Canada | Noel J.-M.,Royal Military College of Canada | Tremblay P.,Defence RandD Canada Ottawa | And 3 more authors.
International Journal of Navigation and Observation | Year: 2011

Automatic dependent surveillance-broadcast (ADS-B) is a system in which aircraft continually transmit their identity and GPS-derived navigational information. ADS-B networks for air traffic monitoring have already been implemented in areas around the world, but ground stations cannot be installed in midocean and are difficult to maintain in the Arctic, leaving a coverage gap for oceanic and high latitude airspace. A potential solution for worldwide tracking of aircraft is through the monitoring of aircraft-transmitted ADS-B signals using satellite-borne receivers. To investigate this possibility, a high altitude balloon experiment was carried out in June 2009 to determine if ADS-B signals can be detected from near space. The Flying Laboratory for the Observation of ADS-B Transmissions (FLOAT) was the first stratospheric platform to collect ADS-B data. The FLOAT mission successfully demonstrated the reception of ADS-B signals from near space, paving the way to the development of a space-based ADS-B system. Copyright © 2011 Raymond Francis et al. Source

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