Overview of New Surveillance Technologies

Transcription

1 Overview of Stanley E. Borek Air Force Research Laboratory Information Directorate

2 Background Concealed Weapons Detection (CWD)/Concealed Explosives Detection (CED) Terahertz Imaging System For CWD Identification of Concealed Explosives via THZ Absorption Spectroscopy Using Principal Component Analysis Electromagnetic CWD at a Distance Non-Linear Acoustic CWD Detecting Concealed Weapons at a Safe Distance Using Active Millimeter Wave Radar Detection and Classification of Concealed Items via Magnetic Signature Analysis Focal Plane Array-Based Millimeter Wave Imaging Radiometer Imaging with Millimeter Wave Focal Plane Arrays Through the Wall Surveillance (TWS) Random Array TWS Imaging via Bistatic Radar Technology Low-Cost Radar Sensors for Locating and Tracking Individuals within Buildings Summary

3 Background AFRL/IF under sponsorship of the Department of Justice s (DOJ), National Institute of Justice (NIJ) Office of Science and Technology (OS&T) currently developing and evaluating advanced CWD and TWS technologies Two categories: Inexpensive, handheld systems for CWD and TWS Fixed or mounted immoveable systems (e.g. portals) for CWD Portable, personal computer (PC) based standoff systems to enable the determination of events during critical incident situations for TWS Objectives: locating hidden weapons on an individual s torso (CWD) locating an individual(s) behind a wall or door (TWS) AFRL/IF is supporting the Department of Homeland Security (DHS) on CWD research efforts via the Homeland Security Advanced Research Projects Agency (HSARPA) Relationship is closely coordinated technical effort through AFRL

4 Concealed Weapons Detection (CWD) /Concealed Explosives Detection (CED)

5 Terahertz Imaging System for Concealed Weapon Detection HSARPA Phase I SBIR Contract - Spire Corporation Program objectives: Measure terahertz atmospheric transmission Define portable standoff imaging system Design proof-of-concept system Estimate system performance Technical approach: Use terahertz FTIR interferometer Heterodyne detection required for maximum sensitivity Stationary transmitter antenna, and rastered receiver antenna Clothing loss assumed at db, 10 db receiver noise figure

6 Terahertz Standoff Imager Design with Heterodyne Detection Using Quantum Cascade Lasers Spire Corporation Illustration of a terahertz standoff imaging system at 50 m target distance.

7 Identification of Concealed Explosives via THz Absorption Spectroscopy Using Principal Component Analysis HSARPA Phase I SBIR Contract Intelligent Optical Systems & RPI THz Spectroscopy for Standoff Detection of Explosives and Weapons THz radiation is safe to humans Frequency dependence of absorbed or reflected THz radiation is indicative of explosives and other dielectric materials Stand off spectroscopic analyzer Efficient reflection over broad wavelength regions is indicative of metals and ceramics Potential weapons detection THz radiation is minimally absorbed by paper, leather, plastic, cardboard, clothing THz radiation can be transmitted through the atmosphere within a window of 0.1 to 3 THz, with the exception of numerous water absorption lines

8 APPROACH TAKEN TO SHOW FEASIBILITY OF IDENTIFICATION AND DETECTION - Intelligent Optical Systems & RPI Obtained absorbance spectra via both transmission and reflection Four explosives: TNT, RDX, HMX, PETN Four non-explosives: sugar,flour, soap, salt Four coverings: paper, polyethylene sheet, cotton cloth, and leather Selected signature wavelengths (reduced dimensions of data sets) Applied principal components analysis (PCA) Reduce dimensionality of data by selection of signature wavelengths Assemble table of absorbances (ABS) (from diffuse reflectance) vs. signature wave number for each explosive compound PCA allows one to calculate ABS along N new coordinates that are orthogonal and that are linear combinations of the original coordinates in order to group similar compounds into closer clusters

9 Basic THz Standoff Detection Concept - Intelligent Optical Systems & RPI Detection is Ultimate Objective Potential Threat Reflected Wavefronts Raster Sweep THz Beam Path Perceived threat. Field of View THz Detector THz Detector 2-Axis Scanning THz Laser (Sequential Monochrome Scanner) Video Camera False color imaging would be used to identify the threat and to classify as to explosive, metal weapon, ceramic, etc

10 Electromagnetic Concealed Weapons Detection at a Distance Features HSARPA Phase I SBIR Contract - Pharad Electromagnetic (EM) spectral analysis approach Wideband millimeter-wave signals used to excite natural resonances on a concealed weapon Measurement of resonances across entire Ka-band (26 40 GHz) Create mm-wave EM signature or fingerprint of target with unique features Wideband mm-wave EM signature identifies object from database of targets Resolution: 2 3 mm with ± 1 db RF power measurement accuracy

11 Electromagnetic Concealed Weapons Detection at a Distance Concept - Pharad Wideband Electromagnetic Millimeter-Wave (Ka-band) Sensors Central Processing Interrogation Zones

12 Non-Linear Acoustic Concealed Weapons Detection (CWD) NIJ & HSARPA Phase I SBIR Contracts Luna Innovations ADVANTAGES Audio sound penetrates clothing and can be safe Ultrasonics is like a laser and highly directional Weapons behave differently than tissue and have resonances that can be detected CHALLENGES Acoustics spread too quickly Ultrasonics has trouble with thick clothing since it is highly attenuating Advanced processing techniques are needed to classify sample signatures to distinguish weapons Existing methods cannot bring advanced signal processing to full advantage

13 Beam-mixing makes acoustics a viable option for CWD Luna Innovations NAC 3. Detect f1 1. Locate f2 f1-f2 2. Penetrate Luna s nonlinear acoustics (NAC) overcomes the penetration/resolution tradeoffs of traditional acoustics. Acoustics is: Cost competitive Sensitive to metals and non-metals Safe and does not raise privacy concerns

14 Detecting Concealed Weapons at a Safe Distance Using Active Millimeter Wave Radar NIJ BAA & HSARPA SBIR Phase I Contracts - Personnel Protection, Inc. Off the shelf collision avoidance radar (77 GHz) Transmit both horizontal and vertical polarization Three modes of operation: Radar detection, threat evaluation, and handoff to camera Computer vision based detection for handoff to radar Man-in-the-loop interaction with the camera to identify targets Algorithms will be developed to process the polarization maps that encompass the target, for the purpose of identification

15 System Concept Personnel Protection, Inc.

16 Detection and Classification of Concealed Items via Magnetic Signature Analysis NIJ Funded BEA - Idaho National Laboratory Under NIJ sponsorship INL has developed an array of magneto-resistive gradiometer sensors configured into a walk-through weapons detection portal Baseline Technology Responds to ferromagnetic materials Accurately pinpoints the number, location and size of weapons Uses freeze-frame video capture technology to document events Further developed to discriminate and classify type of threat Commercialized by View Systems, Inc. as Secure Scan 2000

17 Technology Enhancements to CWD System Idaho National Laboratory Classes of weapons and electronic items produce unique magnetic signatures Advanced signal processing is being developed to discriminate and classify threat and non-threat items Intelligence will be added to automatically screen common non-threat items such as PDAs, cell phones, underwire bras, and shoes containing steel shanks Enhancements allow detection and discrimination of small magnetic field items Can detect and classify a combination of threats when items are sufficiently spatially separated

18 Focal Plane Array-Based Millimeter Wave Imaging Radiometer NIJ Funded Contract - Lockheed Martin Passive detection and measurement of electromagnetic radiation at Millimeter wavelengths Measures contrast between surrounding environment and area undergoing scan Aperture size achieves necessary resolution and stand-off Penetrates opaque materials, such as clothing Utilizes rudimentary Automatic Target Recognition (ATR) Algorithms Brassboard system capable of real time operation with stand-off detection at ~4.6 meters (15 feet)

19 Proof-of-Concept & Commercial Systems Lockheed Martin Brassboard System Brijot/Lockheed Martin System

20 Imaging with Millimeter Wave Focal Plane Arrays NIJ Funded Contract Raytheon Vision Systems/UCLA Bolometer Based MMW Imager Physics Bowtie Shaped Bridge PMMWI - Released VOX Bolometer Pixel and MicroAntenna C Connections to Readout Circuitry Nitride Legs for Thermal Isolation Antenna Captures mmw Radiation Energy Coupled to Bolometer mmw Power Flows from Antenna through Bridge Square Bolometer Bridge

21 Through the Wall Surveillance (TWS)

22 Random Array TWS Imaging via Bistatic Radar Technology NIJ Funded Contract Akela, Inc. DISTRIBUTED IMAGING NETWORK CONCEPT Individuals and vehicles become sensor nodes Random array improves imaging by reducing ghosts Wireless network receives data and distributes information View of operational space changes as sensors move Modular approach allows operational flexibility Network centric sensor

23 DISTRIBUTED IMAGING NETWORK CURRENT ARCHITECTURE AKELA, INC. Completely wireless system is program goal

24 Low-Cost Radar Sensors for Locating and Tracking Individuals within Buildings NIJ Award University of Texas at Austin Proposed: A sensor concept combining Doppler and Direction-Of-Arrival (DDOA) information to track multiple movers through walls Objectives: (1) Develop low-cost radar sensor concepts for personnel detection based on commercial wireless products (2) Collect an extensive database using the developed sensors and to exploit the data for personnel location, tracking, and ID Unique Features: (1) Use of Doppler features from human movements to suppress stationary clutter such as buildings and walls (2) Use very few receiver elements to obtain DOA tracking of multiple human targets (3) Use of Mass-market wireless products for very low cost sensor development Anticipated (1) Novel sensor design and demonstration Results: (2) Database of human radar signatures & radar features of human movements knowledge base

25 Summary DOJ/NIJ and DHS have combined resources to actively develop solutions to the tough challenges facing technology applications to state-of-the-art systems for CWD, CED, and TWS Research & Development efforts range from practical technical applications of acoustic, radar, and terahertz frequencies Seven technology applications for CWD presented; one for CED, two for TWS Research results in the area of technology applications of Terahertz frequencies for CWD and CED has been positive Millimeter Wave Imaging show promise for accomplishing reasonable stand-off operation for CWD Nonlinear Acoustic Technology shows promise for accomplishing CWD via innovative application of frequency scanning and resonance principles Bistatic Radar Technology is a novel approach for dynamically accomplishing 3D imaging for TWS AFRL/IF is working closely with DOJ/NIJ and DHS to develop, mature, and place these technologies in the field as viable systems