3,642 research outputs found

    Automatic RADAR Target Recognition System at THz Frequency Band. A Review

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    The development of technology for communication in the THz frequency band has seen rapid progress recently. Due to the wider bandwidth a THz frequency RADAR provides the possibility of higher precision imaging compared to conventional RADARs. A high resolution RADAR operating at THz frequency can be used for automatically detecting and segmenting concealed objects. Recent advancements in THz circuit integration have opened up a wide range of possibilities for on chip applications, like of security and surveillance. The development of various sources and detectors for generation and detection of THz frequency has been driven by other techniques such as spectroscopy, imaging and impulse ranging. One of the central vision of this type of security system aims at ambient intelligence: the computation and communication carried out intelligently. The need for higher mobility with limited size and power consumption has led to development of nanotechnology based THz generators. In addition to this some of the soft computing tools are used for detection of radar target automatically based on some algorithms named as ANN, RNN, Neuro-Fuzzy and Genetic algorithms. This review article includes UWB radar for THz signal, its characteristics and application, Nanotechnology for THz generation and issues related to ATR

    Remote Detection of Concealed Guns and Explosives

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    A reliable method of remotely detecting concealed guns and explosives attached to the human body is of great interest to governments and security forces throughout the world. This thesis describes the development and trials of a new remote non-imaging concealed threat detection method using active millimetre wave radar using the microwave and mmwave frequencies bands 14 – 40 and 75 – 110 GHz (Ku, K, Ka and W). The method is capable of not only screening for concealed objects, like the current generation of concealed object detectors, but also of differentiating between mundane and threat objects. The areas focused upon during this investigation were: identifying the impact of different commonly worn fabrics as barriers to detection; consulting with end users about their requirements and operational needs; a comparison of different frequency bands for the detection of guns and explosives; exploring the effects of polarisation on object detection; a performance comparison of different detection schemes using Artificial Neural Networks; improving existing data acquisition systems and prototyping of a real-time capture system

    Open Area Concealed Weapon Detection (CWD) Sensor System Development

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    The detection of concealed weapons is a key requirement when considering the personal security of individuals in a public environment, such as a sporting event, airports, festivals, schools or universities etc. Hence, being able to efficiently discover any illicit items hidden within luggage or underneath the clothes of an individual, for example, is essential. The development of a concealed weapon detection (CWD) system, which efficiently addresses the issue of accurate identification and classification of dangerous objects, will aid in minimising the potential danger for a high volume of individuals in open area environments. Searching all visitors who pass through security points is normally an inefficient process, comprising of individual manual inspection, which often leads to congestion at the entrance of the event. Conversely, highly sophisticated systems with minimal manual intervention, utilising image scanning, are typically claimed to be a high risk to personal privacy and the possible leakage of confidential information, such as identification of belongings, where carried items underneath clothes are displayed on the screen, even if no weapon is detected. The traditional weapon detection process depends upon the manual recognition of a threat with currently available commercial systems generally being unable to achieve the accurate recognition of potential threat objects from other non-threat items, often resulting in what `the generation of false alarms'. Therefore, the development of a CWD system to accurately determine and categorise different illicit targets, such as knives and guns etc, in real time and efficiently monitor the public security in an open area environment, is increasingly becoming an essential requirement. Hence an innovative CWD solution that uses the pulse-induction (PI) technique to recognise and classify threat objects, through the novel characterisation of the induced electromagnetic signal utilising a sigma delta analogue to digital modulation device to yield an analysable signature is proposed. In comparison, to typical digital conversion processes, with excessive data samples required to provide distinguishable object signal characteristic information, the system features a single bit data flow from a sigma delta, to simplify the analogue sampling measurement. The sigma delta modulating approach facilitated a novel algorithm development to accurately identify potential weapons, enabling features (shape, size and material) of a target object to be identifiable within the signature. The weapon detection scheme delivers the signature evaluation based on marked points of the single bit stream facilitating the specific threat characteristics of the detected target to be identified in real-time. A practical, FPGA based implementation of the object identification procedure proved the concept of an algorithm to identify object characteristics of threat objects, principally that of a typical hand-held weapon (knife) through the identification of weapon characteristics, e.g. edge sharpness, thus efficiently differentiating between potential threats from other objects of similar shape, mass, etc. All the key aspects of an open area weapon detection system, operating in real-time, have been proven, thus future development and implementation of the proposed algorithm for an individual sensor could be expanded to form a multi-detection system to track a weapon trajectory, contributing to the development of an accurate and efficient identification of weapons in an open area environment

    Security and the smart city: A systematic review

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    The implementation of smart technology in cities is often hailed as the solution to many urban challenges such as transportation, waste management, and environmental protection. Issues of security and crime prevention, however, are in many cases neglected. Moreover, when researchers do introduce new smart security technologies, they rarely discuss their implementation or question how new smart city security might affect traditional policing and urban planning processes. This systematic review explores the recent literature concerned with new ‘smart city’ security technologies and aims to investigate to what extent these new interventions correspond with traditional functions of security interventions. Through an extensive literature search we compiled a list of security interventions for smart cities and suggest several changes to the conceptual status quo in the field. Ultimately, we propose three clear categories to categorise security interventions in smart cities: Those interventions that use new sensors but traditional actuators, those that seek to make old systems smart, and those that introduce entirely new functions. These themes are then discussed in detail and the importance of each group of interventions for the overall field of urban security and governance is assessed

    Cross-layer Optimized Wireless Video Surveillance

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    A wireless video surveillance system contains three major components, the video capture and preprocessing, the video compression and transmission over wireless sensor networks (WSNs), and the video analysis at the receiving end. The coordination of different components is important for improving the end-to-end video quality, especially under the communication resource constraint. Cross-layer control proves to be an efficient measure for optimal system configuration. In this dissertation, we address the problem of implementing cross-layer optimization in the wireless video surveillance system. The thesis work is based on three research projects. In the first project, a single PTU (pan-tilt-unit) camera is used for video object tracking. The problem studied is how to improve the quality of the received video by jointly considering the coding and transmission process. The cross-layer controller determines the optimal coding and transmission parameters, according to the dynamic channel condition and the transmission delay. Multiple error concealment strategies are developed utilizing the special property of the PTU camera motion. In the second project, the binocular PTU camera is adopted for video object tracking. The presented work studied the fast disparity estimation algorithm and the 3D video transcoding over the WSN for real-time applications. The disparity/depth information is estimated in a coarse-to-fine manner using both local and global methods. The transcoding is coordinated by the cross-layer controller based on the channel condition and the data rate constraint, in order to achieve the best view synthesis quality. The third project is applied for multi-camera motion capture in remote healthcare monitoring. The challenge is the resource allocation for multiple video sequences. The presented cross-layer design incorporates the delay sensitive, content-aware video coding and transmission, and the adaptive video coding and transmission to ensure the optimal and balanced quality for the multi-view videos. In these projects, interdisciplinary study is conducted to synergize the surveillance system under the cross-layer optimization framework. Experimental results demonstrate the efficiency of the proposed schemes. The challenges of cross-layer design in existing wireless video surveillance systems are also analyzed to enlighten the future work. Adviser: Song C

    Cross-layer Optimized Wireless Video Surveillance

    Get PDF
    A wireless video surveillance system contains three major components, the video capture and preprocessing, the video compression and transmission over wireless sensor networks (WSNs), and the video analysis at the receiving end. The coordination of different components is important for improving the end-to-end video quality, especially under the communication resource constraint. Cross-layer control proves to be an efficient measure for optimal system configuration. In this dissertation, we address the problem of implementing cross-layer optimization in the wireless video surveillance system. The thesis work is based on three research projects. In the first project, a single PTU (pan-tilt-unit) camera is used for video object tracking. The problem studied is how to improve the quality of the received video by jointly considering the coding and transmission process. The cross-layer controller determines the optimal coding and transmission parameters, according to the dynamic channel condition and the transmission delay. Multiple error concealment strategies are developed utilizing the special property of the PTU camera motion. In the second project, the binocular PTU camera is adopted for video object tracking. The presented work studied the fast disparity estimation algorithm and the 3D video transcoding over the WSN for real-time applications. The disparity/depth information is estimated in a coarse-to-fine manner using both local and global methods. The transcoding is coordinated by the cross-layer controller based on the channel condition and the data rate constraint, in order to achieve the best view synthesis quality. The third project is applied for multi-camera motion capture in remote healthcare monitoring. The challenge is the resource allocation for multiple video sequences. The presented cross-layer design incorporates the delay sensitive, content-aware video coding and transmission, and the adaptive video coding and transmission to ensure the optimal and balanced quality for the multi-view videos. In these projects, interdisciplinary study is conducted to synergize the surveillance system under the cross-layer optimization framework. Experimental results demonstrate the efficiency of the proposed schemes. The challenges of cross-layer design in existing wireless video surveillance systems are also analyzed to enlighten the future work. Adviser: Song C

    A Millimeter-Wave Radar Microfabrication Technique and Its Application in Detection of Concealed Objects.

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    Millimeter-wave (MMW) radars are envisioned for a number of safety and security applications such as collision-avoidance, navigation and standoff target detection in all weather conditions. This work focuses on two MMW radar applications: (1) phenomenology of radar backscatter from the human body for the purpose of identification and detection of concealed objects on the body (2) microfabrication of advanced MMW radar to achieve compact and low-cost systems for autonomous navigation. In MMW band, the wavelength (1 mm ~ 1 cm) is long enough to allow signal penetration through cluttered atmosphere and clothing with little attenuation and short enough to allow for fabrication of small-size radar systems. Hence, this frequency band is well suited for the design of small sensors capable of obstacle detection and navigation in heavily cluttered environment and detecting hidden objects carried by individuals. For this purpose, a novel non-imaging approach is developed for distinction of walking human body and concealed carried object using polarimetric backscatter Doppler spectrum. This approach does not need radiometric calibration of the radar and preparation of the subject for radar interrogation. It is shown that a coherent polarimetric radar at W-band (95 GHz) or higher frequencies can be used for standoff detection of concealed carried objects. Motivated by these results, the thesis also includes an investigation on developing a technology for compact MMW radar systems. A micromachined, high-resolution, compact and low-power imaging MMW radar operating at 240 GHz intended for obstacle detection in complex environment is introduced. A frequency scanning antenna array micromachined from three layers of stacked silicon wafers is designed to provide 20 beamwidth in azimuth and 80 in elevation with azimuthal beam scanning range of ± 250. The frequency beam scanning is enabled by a meander rectangular waveguide with a slot array on its broad wall to feed linear microstrip patch antennas microfabricated on a suspended Parylene membrane. This technique offers high fabrication precision; provide easy fabrication and integration with active devices. The performances of the passive components of the radar system are verified using a WR-3 S-parameter and a near-field measurement systems.Ph.D.Electrical EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/91484/1/mvahid_1.pd

    Advances in Intelligent Robotics and Collaborative Automation

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    This book provides an overview of a series of advanced research lines in robotics as well as of design and development methodologies for intelligent robots and their intelligent components. It represents a selection of extended versions of the best papers presented at the Seventh IEEE International Workshop on Intelligent Data Acquisition and Advanced Computing Systems: Technology and Applications IDAACS 2013 that were related to these topics. Its contents integrate state of the art computational intelligence based techniques for automatic robot control to novel distributed sensing and data integration methodologies that can be applied to intelligent robotics and automation systems. The objective of the text was to provide an overview of some of the problems in the field of robotic systems and intelligent automation and the approaches and techniques that relevant research groups within this area are employing to try to solve them.The contributions of the different authors have been grouped into four main sections:• Robots• Control and Intelligence• Sensing• Collaborative automationThe chapters have been structured to provide an easy to follow introduction to the topics that are addressed, including the most relevant references, so that anyone interested in this field can get started in the area
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