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Marchetti C.,Defence R and D Canada Ottawa
Proceedings of the International Astronautical Congress, IAC | Year: 2014

The Maritime Monitoring and Messaging Microsatellite (M3MSat) is a technology demonstration mission that will contribute to solving the current challenges of Canadian maritime surveillance faced by the Canadian Armed Forces (CAF). M3MSat is a joint project between the Canadian Space Agency (CSA) and Defence Research and Development Canada (DRDC). M3MSat will be used to evaluate the ability to perform high performance space-based detection of ship transmitted Automated Information System (AIS) signals in dense shipping regions of the Earth. The microsatellite will also perform global maritime surveillance. Integration of the information gathered by the satellite into a recognized maritime picture will make it possible to identify and track marine traffic, determine the direction and speed of vessels, ensure that ships are travelling legally through Canadian waters, and help ensure safety of life at sea. This will ultimately serve to protect public security, national interests, and global operations by improving Intelligence, Surveillance and Reconnaissance (ISR) capabilities within Canada. In addition to the AIS data exploitation, the developmental experience with M3MSat will further increase DRDC's expertise in microsatellite system design and operations. This paper discusses the microspace philosophy adopted by DRDC in the development of M3MSat. It presents the lessons learned throughout the satellite development and provides recommendations on how those lessons could be integrated into the development of future CAF microsatellite systems. Most specifically, it addresses project management, requirements definition, standardization and operations. Based on the M3MSat experience, the paper highlights that it is possible to successfully manage a microsatellite project with more than one client organization, although this situation can easily result in a higher number of requirements and expansion of mission scope. It also underlines that striving to achieve bus standardization does not always bring cost savings. Finally, it establishes that streamlined operations can be adequate to achieve microsatellite operational readiness of a technology demonstrator.

Kirkland D.,Defence R and D Canada Ottawa
Progress in Electromagnetics Research | Year: 2012

This paper presents a method for focusing a moving target in single channel SAR data utilizing a novel technique for range migration correction. The First Order Keystone transform is first applied to remove the range-walk of the moving target signature. A search procedure based on maximizing a contrast cost function is then employed to determine the phase correction which compensates for the remaining range curvature. Finally an adaptive notch filter is used to construct an estimate of the azimuth compression filter necessary to focus the moving target. An experimental result is provided for airborne SAR data to demonstrate the feasibility of the approach.

Mok I.,Defence R and D Canada Ottawa
Proceedings of the International Astronautical Congress, IAC | Year: 2014

Budgets for traditional "big" space mission are generally higher in comparison to those of "microspace" missions. Defence Research and Development Canada (DRDC) used the Maritime Monitoring and Messaging Microsatellite (M3MSat) project [4, 7], a Canadian maritime surveillance satellite, to apply this low cost microspace approach [3] when building the primary Ground Station (GS). DRDC prepared a GS that will operate the microsatellite with a small operations team. Key to DRDC's implementation of the GS was satellite control automation to conduct operations with M3MSat. This paper will document how DRDC designed, implemented, built, and validated their Mission Operations Centre (MOC) and GS as well as the training of their operators. Copyright © 2014 by the International Astronautical Federation. All rights reserved.

Chiu S.,Defence R and D Canada Ottawa | Dragosevic M.,MD TerraBytes Inc.
IEEE National Radar Conference - Proceedings | Year: 2011

A highly efficient algorithm is proposed to collect all the energy of a moving target, irrespective of its speed and direction, and has been applied to real RADARSAT-2 MODEX (Moving Object Detection EXperiment) data. Results show that the algorithm maximizes the SCNR (signal-to-clutter-plus-noise ratio) in existing spaceborne SAR-GMTI (Synthetic Aperture Radar Ground Moving Target Indication) systems with a minimal increase in the processing load. Instead of attempting to match to all possible radial speeds of unknown movers in order to adequately apply SAR focusing, the algorithm requires only two full iterations of SAR processing per channel. The first iteration is a static world, full PRF (pulse repetition frequency) bandwidth SAR processing step. The second iteration is two DC (Doppler centroid) offset, half PRF bandwidth SAR processing iterations. By coherently combining the SAR-DPCA (displaced phase center antenna) images, the energy of movers can be completely recovered. © 2011 IEEE.

Wang S.,Defence R and D Canada Ottawa | Wang S.,Communications Research Center Canada | Inkol R.,Defence R and D Canada Ottawa | Jackson B.R.,Defence R and D Canada Ottawa
2012 26th Biennial Symposium on Communications, QBSC 2012 | Year: 2012

Under the assumption of a log-normal path loss model, maximum likelihood (ML) emitter location estimators are derived for both received signal strength (RSS) and received signal strength difference (RSSD) information. It is then shown that these ML estimators are identical, contrary to the seemingly common perception that the RSS-based ML location estimator should outperform the RSSD-based ML location estimator. The Cramer-Rao lower bounds (CRLB) for the average miss distance are also shown to be identical. Using the least squares estimation criterion, a non-linear least squares (NLS) emitter location estimator is also formulated in this paper for comparison. These theoretical developments are illustrated by computer simulation experiments. © 2012 IEEE.

Wu C.,Defence R and D Canada Ottawa | Young A.,Defence R and D Canada Ottawa
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2013

Research experience has shown that it is expensive to design, build and test a RF/microwave system that is comprised of various RF/microwave components. In order to mitigate the problem, High-Fidelity Modeling and Simulation (HFM&S) is a practical approach that includes high-fidelity behavioural model (HFBM) of the receiving system and scenarios embedded with different Concept of Operations (CONOPS). HFM&S is also an essential way to develop receiving system specifications that can be used for system validation and verification. This paper presents the HFBM of a wideband digital receiver using Matlab/Simulink® and the RF Toolbox™/SimRF™, and the use of the model to build a multi-channel receiving system that has a linear antenna array. The receiving system is installed on an UAV to intercept a ground-based emitter signal in a scenario that is built in Systems Tool Kit®. Through the design and build of the UAV receiver and its deployment in a scenario, this paper demonstrates the following: what is meant by HFBM of a system and how it can simulate real hardware; how signal integrity in the HFM&S can be and should be retained; why amplitude and phase are important for signal waveform level M&S; why the modern high performance computing technology should be used for signal waveform level M&S; and why the development of a realistic scenario is an important part of HFM&S for application CONOPS development?. © 2013 SPIE.

Song R.,Defence R and D Canada Ottawa | Mason P.C.,Defence R and D Canada Ottawa
Proceedings - IEEE Military Communications Conference MILCOM | Year: 2010

The Optimized Link State Routing protocol (OLSR) has valuable features for mobile ad hoc networks such as no route discovery delay and ease of integration into existing systems, which makes it well-suited for time critical military and emergency rescue applications. However, security, trust, and robustness are still a sizable challenge for OLSR, especially for military applications. In this paper, we first highlight potential attacks, vulnerabilities, and key countermeasure points of OLSR in terms of security. Based on this analysis, we propose a new robust OLSR protocol for strict military environments. We demonstrate that the proposed protocol can defend against various sophisticated attacks and is manageable in terms of the trade off among security, trust, and performance. ©2010 IEEE.

Chan B.,Defence R and D Canada Ottawa
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2010

DRDC Ottawa is investigating high resolution synthetic aperture radar (SAR) techniques to perform 3-D imaging through walls in urban operations. Through-wall capabilities of interest include room mapping, imaging of in-wall structures, and detection of objects of interest. Such capabilities would greatly enhance situational awareness for military forces operating in the urban battle space. Current activities include hardware and software development and testing of an L-band through-wall SAR (TWSAR) system. Detection algorithms and automatic target recognition (ATR) systems are under investigation using experimental 2-D data. ATR may be more difficult in urban environments due to the high number of detectable objects and multi-path artifacts. Furthermore, penetrating through walls presents a formidable challenge as wall effects can greatly interfere with image quality inside buildings. By classifying wall material, wall compensation algorithms can be applied to enhance the image. In this paper, we present results from our preliminary investigation on detecting internal and external wall structures and their features (including doors and windows as well as internal wall construction) from scenes acquired with a single channel L-band TWSAR system. We evaluate the effectiveness of automatic detection based on the contourlet domain hidden Markov tree in the context of detecting wall edges and building features, while minimizing the amount of false edge detection. This work will form the basis of wall compensation algorithm development. The detection technique will also be used to detect objects of interests beyond walls once the SAR images have been wall compensated. © 2010 Copyright SPIE - The International Society for Optical Engineering.

Jones C.T.,Dalhousie University | Sikora T.D.,Millersville University of Pennsylvania | Vachon P.W.,Defence R and D Canada Ottawa | Wolfe J.,Defence R and D Canada Ottawa
Journal of Atmospheric and Oceanic Technology | Year: 2012

The Canadian Forces Meteorology and Oceanography Center produces a near-daily ocean feature analysis, based on sea surface temperature (SST) images collected by spaceborne radiometers, to keep the fleet informed of the location of tactically important ocean features. Ubiquitous cloud cover hampers these data. In this paper, a methodology for the identification of SST front signatures in cloud-independent synthetic aperture radar (SAR) images is described. Accurate identification of ocean features in SAR images, although attainable to an experienced analyst, is a difficult process to automate. As a first attempt, the authors aimed to discriminate between signatures of SST fronts and those caused by all other processes. Candidate SST front signatures were identified in Radarsat-2 images using a Canny edge detector. A feature vector of textural and contextual measures was constructed for each candidate edge, and edges were validated by comparison with coincident SST images. Each candidate was classified as being an SST front signature or the signature of another process using logistic regression. The resulting probability that a candidate was correctly classified as an SST front signature was between 0.50 and 0.70. The authors concluded that improvement in classification accuracy requires a set of measures that can differentiate between signatures of SST fronts and those of certain atmospheric phenomena and that a search for such measures should include a wider range of computational methods than was considered. As such, this work represents a step toward the goal of a general ocean feature classification algorithm. © 2012 American Meteorological Society.

Sandirasegaram N.,Defence R and D Canada Ottawa | Liu C.,Defence R and D Canada Ottawa
IET Radar, Sonar and Navigation | Year: 2011

In recent years, large numbers of radar images are collected but there is neither time nor enough manpower to go through each collected image. Researchers in the automatic target recognition (ATR) field have developed automated algorithms and tools to analyse each image and obtain higher recognition rate and fewer false alarms but there is still a need for improvement in these aspects. In this study, we have investigated various polarimetric and non-polarimetric techniques and recommended the best ATR approach among those analysed for higher recognition rate and least false alarm rate. The experimental results show that self-organising map (SOM) feature extraction technique with a two-dimensional Fourier transform (2DFFT) algorithm has a better classification rate and a lower false alarm rate. The classifier used here was AND Corporation's holographic neural technology (HNeT) classifier. The SOM technique using |HH|, |HV| and |VV| achieved 98.9% correct classification over the detected targets and reduced the false alarm rate to 8.2%. An ATR system trained with both target and not-a-target class data produced a lower false alarm rate compared with ATR systems trained with target samples alone. This study will help in selection of appropriate methods for future ATR system implementations. In addition, it will assist image analysts (IAs) in choosing appropriate techniques and training datasets to perform their operational tasks. © 2011 © The Institution of Engineering and Technology.

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