Quist B.T.,Brigham Young University |
Quist B.T.,Imsar Llc |
Jensen M.A.,Brigham Young University
IEEE Transactions on Information Forensics and Security | Year: 2013
Establishing secret keys from the commonly-observed randomness of reciprocal wireless propagation channels has recently received considerable attention. We consider such key establishment between two multiantenna nodes that use beamforming for communication, showing that the upper bound on the number of key bits that can be generated from the channel observations can be maximized by properly probing the channel. Specifically, we demonstrate that the eigenvectors of the channel spatial covariance matrix should be used as beamformer weights during channel estimation and we optimize the energy allocated to channel estimation for each beamformer weight under a total energy constraint. Finally, by assuming that the channel covariance is separable, we illustrate implementation of the technique for practical beamforming systems and more advanced signal models that incorporate antenna mutual coupling. © 2013 IEEE.
Imsar Llc | Date: 2013-06-11
Automated self contained electronic surveillance devices that can be deployed to gather evidence or intelligence in remote locations; Electronic devices for locating and tracking organisms and inanimate objects using radio frequency; Electronic devices used to located lost objects employing radio frequency; Encoded micro particulates, tags and taggants of plastic, metal or silicate for use in the field of passive labeling, tracing or tracking of persons, animals, vehicles or goods of any kind; Radar apparatus; Radar detectors; Radar object detectors for use on vehicles; Radar receivers with amplifiers; Radio frequency generators for supplying radio-frequency energy; Radio frequency identification (RFID) credentials, namely, cards and tags, and readers for radio frequency identification credentials; Radio frequency identification (RFID) tags; Radio frequency identification tag readers; Radio tomographic imaging apparatus for tracking movement; Radio-frequency identification (RFID) readers; Radio-frequency identification (RFID) tags. Radar detection; Radio tomographic imaging services; Technical verification and validation of instrumentation radar systems.
Imsar Llc | Date: 2016-01-07
A radio frequency identification (RFID) tag includes a power source, a transmitter to transmit a unique identifier, and a receiver operatively coupled to the transmitter and to receive low-frequency signals from an active RFID transceiver located in the vicinity. The transmitter is activated by the power source responsive to the receiver receiving a wake up command at a predetermined low frequency from the active RFID transceiver. An RFID transceiver includes an antenna, non-transitory computer-readable medium storing instructions and a transmitter to transmit low-frequency signals to RFID tags through the antenna. A processing device of the RFID transceiver can execute the instructions to insert a station identifier (ID) into the low-frequency signals that direct the RFID tags to retransmit the station ID, wherein the station ID identifies an approximate location of the RFID tags.
Agency: Department of Defense | Branch: Air Force | Program: SBIR | Phase: Phase I | Award Amount: 149.96K | Year: 2012
ABSTRACT: ImSAR LLC and Solid State Scientific Corporation (SSSC) propose to leverage ImSAR's proven radar hardware and ground processing capabilities along with SSSC's expertise in radar signal processing, SAR-based GMTI, and automatic/assisted target recognition to advance the state of the art in dismount detection in small SWaP radars. BENEFIT: GMTI for small SWaP radars has the potential to significantly enhance battlefield commander tactical awareness. Non-military applications could include border patrol and search and rescue applications.
Agency: Department of Defense | Branch: Air Force | Program: SBIR | Phase: Phase II | Award Amount: 750.00K | Year: 2012
Agency: Department of Defense | Branch: Air Force | Program: SBIR | Phase: Phase I | Award Amount: 99.48K | Year: 2011
ImSAR and BYU propose to use SAR/STAP/MIMO techniques to provide continous navigation in a GPS denied environment for UAS. The team has expertise in precision location of UAVs targets using a variety of methods inlcuding radar. BENEFIT: Commercial aviation and UAS missions that have become dependant on GPS navigation solutions will have an alternative during GPS outage or in jammed situations.
Agency: Department of Defense | Branch: Navy | Program: SBIR | Phase: Phase I | Award Amount: 79.93K | Year: 2014
Radar sensor suites used by seekers and ISR platforms frequently must collect multiple types of radar data. In addition to moving target indication (MTI) data used for target tracking (tracking data), such systems often also collect high resolution radar information about specific targets in order to facilitate automatic target recognition (ATR) or classification (ATR data). This ATR data can include Synthetic Aperture Radar (SAR) or Inverse Synethetic Aperture Radar (ISAR) imaging data as well as non-imaging data such as High Range Resolution (HRR) profiles of targets. Currently, these platforms must switch radar modes in order to collect ATR data, potentially giving up the ability to maintain target tracks while images are being generated. Gathering ATR data can take from a few seconds to tens of seconds depending on system parameters and the imaging method used. The ability to obtain high resolution ATR data while simultaneously tracking targets would significantly improve the usability of tracking sensors. It would allow tracking of high-priority targets to continue while some targets are identified. This ability can make the difference between missing a high priority target or not, for both seeker and ISR platforms. In the proposed effort, IMSAR will design and evaluate methods to enable radar systems to collect high resolution ATR data while maintaining target track.
Agency: Department of Defense | Branch: Army | Program: SBIR | Phase: Phase I | Award Amount: 99.82K | Year: 2014
Historically, radar hardware is designed for a particular application with particular analog hardware components. This greatly limits the flexibility of existing radar systems. Modern digital technology can be used to greatly increase radar hardware flexibility and capability. IMSAR has already designed, developed, and deployed a flexible digital radar, the NanoSAR C, that operates at >1 GHz RF bandwidth, uses a configurable direct digital synthesizer (DDS) for Tx signal generation, operates at many frequencies, and includes onboard FPGA and DSP technology for preprocessing. The proposed effort will improve the NanoSAR C by adding a pulsed-mode capability, enhancing the preprocessing and signal generation capabilities, and facilitating the interconnection of multiple units into a single array. The resulting radar design will be applicable with minimal modification to a wide range of applications, from spaceborne and seeker radars to SWaP-constrained ISR applications on UAVs. It will also be capable of performing complex functions such as anti-jamming; frequency hopping; pulse shaping; embedding data in transmit signals; and performing communications relay and SIGINT functions. The unprecedented configurability and capability of the resulting digital radar system will significantly increase the usefulness of radar equipment to the United States military and to other commercial organizations.
Agency: Department of Defense | Branch: Air Force | Program: SBIR | Phase: Phase II | Award Amount: 1.19M | Year: 2013
ABSTRACT: Ground Surveillance Radar (GSR) is a fundamental and proven component of Department of Defenses (DoD) Battlefield Awareness. Advanced radar systems on large remotely piloted aircraft (RPAs) include Synthetic Aperture Radar (SAR) and Ground Moving Target Indicators (GMTI). The ability to identify and track vehicles and dismounts has become a key focus. Small (< 10 lb) radars with SAR imaging capabilities exist for RPAs, but GMTI capabilities are not yet available on Tier I/II programs of record. Incorporating dismount detection and tracking capabilities into small RPAs will be a significant force multiplier and improve the tactical commanders Battlefield Awareness and is the focus of this Advanced Radar Concepts for Small RPAs program. The Advanced Radar Concepts for Small RPAs Phase I program clearly demonstrates the feasibility of innovative approaches needed to bridge the gap between advanced weapon system radars and small Size Weight & Power (SWaP) radar systems that can operate on Tier I/II programs of record RPAs. The objective of Phase II is to mature small SWaP GMTI technology and demonstrate real-time GMTI radar capabilities within the stringent SWaP constraints of these Teir I/II RPAs. BENEFIT: GMTI and dismount detection radar is a force multiplier that will help the tactical commander to dispel the fog of war and the uncertainty of ever changing battlefield conditions. Pushing this important and proven technology down to the smallest RPAs will provide accurate and timely situational awareness information to commanders of forward operational bases and the small tactical units critical for the protection of personnel and concentration of force. Moreover, agencies responsible for border patrol, law enforcement, and search and rescue operations will benefit from this technology. GMTI will improve their ability to efficiently search and patrol large areas. They will be able to concentrate their efforts where it is most needed while minimizing risk to personnel.
Agency: Department of Defense | Branch: Army | Program: SBIR | Phase: Phase II | Award Amount: 613.91K | Year: 2010
A major problem faced by our warfighters utilizing a Micro Air Vehicle is its limited capability to provide wide area situational awareness and sense combatants under low visibility conditions such as night, rain, fog, dust, snow and sand. The other issue is that once a combatant is identified the warfighter must personally engage the combatant exposing the warfighter to enemy fighter. If the MAV had the ability to sense 24/7 over a wide area, identify the target and then cue munitions the warfighter could remain at safe standoff during an entire mission reducing the chance of himself and his team from coming under fire. In Phase I we demonstrated that is possible to fly a GMTI radar on the MAV and that we can integrated the camera and laser inside the turret ball of the MAV. In Phase II we will completely integrate the GMTI radar/Day&Night Camera/Laser into a fully integrated module that will be attached and flown on the Honeywell MAV. This is similar to have a short range version of the sensor package of a Apache Longbow on a 15lb. MAV.