Wang Z.,Intelligent Fusion Technology, Inc |
Zekavat S.A.R.,Michigan Technological University
IEEE Transactions on Mobile Computing
This paper presents an Omnidirectional mobile target-node (TN) localization technique in nonline-of-sight (NLOS) scenarios. Here, a TN cooperates with base-nodes (BNs) with antenna-arrays to allow them to find its position via time-of-arrival (TOA) and direction-of-arrival (DOA) measurements. When line-of-sight (LOS) channel is available, each BN localizes TNs in its coverage area with reasonable accuracy. However, when LOS channel is obstructed, considerable localization error is generated. To avoid NLOS error, a technique is proposed to identify if a TN is in the LOS of multiple BNs or not. The technique enables BNs to determine and localize their shared reflection points, and to localize NLOS TNs. The paper assumes single-bounce-reflection NLOS channel between BNs and TNs. In NLOS scenarios, when three or more reflection points are shared by a TN and multiple sets of BNs, the shared reflection points are localized via DOA fusion, and then the TN is localized via TOA fusion. The equations for NLOS identification, shared reflection points determination and localization and NLOS TN localization are theoretically derived. Simulations are conducted to evaluate the proposed technique in terms of the probability of false alarm and misdetection of NLOS identification and shared reflection points determination, and NLOS TN localization accuracy. © 2012 IEEE. Source
Agency: Department of Defense | Branch: Air Force | Program: STTR | Phase: Phase I | Award Amount: 150.00K | Year: 2015
ABSTRACT: This proposal presents an Air Force Satellite Control Network (AFSCN) upgrade scheme using smart antenna and cognitive satellite radio techniques. On the remote tracking station (RTS) side, switched beam smart antenna, distributed beam forming technique, multiple access technique based on FDMA and/or CDMA are applied to obtain multiple satellites reception objective. On the satellite side, smart antenna is applied to the RF interference (RFI) and speed up the antenna mainlobe turning for shortening the lengthy TT&C scheduling; cognitive radio sensing is used on satellite to monitor the RFI and extract the RFI pattern for minimizing RFI in TT&C scheduling. In addition, GPS based ranging technique is applied for satellite localization to alleviate the RTSs satellite tracking work load. We modeled the end to end uplink communication from RTS transmitter to satellite receiver for uplink power and link budget calculation. The RF interferences coming from undesired RTS and 3G/4G personal communication system are modeled separately and then combined for RFI minimization in the TT&C scheduling process. We also proposed long term solutions using phase array antenna, cognitive satellite radio and real time TT&C scheduling techniques. BENEFIT: The proposed techniques (1) to (5) can be directly used for AFSCN TT&C multiple satellites reception and satellite RFI minimization in congested, contested radio spectrum conditions; (6) can be used for any satellite localization/ranging; and, (7) can be used for AFSCN multiple satellites reception in wide angle range with smart antennas on satellites in the future when the PAA cost is lower than the SATOP cost reduction using PAA. The technique (2) can also be applied in Space Situational Awareness (SSA) and RF environment monitoring missions to effectively detect and localize ground radar/satellite-communication-station/jammers for early RF threat warning and indications, such as transition into existing Wideband Global Spectrum Monitoring System (WGSMS) program. It can also be applied on CubeSat or small UAV. When applied on CubeSat, it can be directly used for monitoring the region with A2AD capability; when applied on UAV, it can be used for battlefield monitoring. We already have close connections with DoD and industry communities. The market for military is quite large and IFT has successfully transitioned research prototype for inclusion in DoD contractor research simulations. We also recognize commercial application of this project with the concepts being developed. The proposed system can be directly used for commercial satellite TT&C, and the technique (2) can be applied on small UAS by Department of Homeland Security and US Coast Guard for monitoring county border, or polices for fast response to disaster.
Agency: Department of Defense | Branch: Air Force | Program: STTR | Phase: Phase I | Award Amount: 150.00K | Year: 2015
ABSTRACT: In this proposal a Game-theoretic Universal Anti-RFI Defense (GUARD) framework for Satellite Communications is proposed. Key components of the GUARD framework include i) Radio Frequency Interferences (RFI) modeling and impact evaluation infrastructure, which allows the evaluation of the impact of RFI from various sources, and provides a comprehensive RFI knowledge base to SATCOM; ii) RFI sensing and inference infrastructure, which utilizes on-site measurements from supporting sensors and users to identify the location, nature and scope of the RFI, and makes inference about the RFI source (type, location, capacity, etc.) based on the RFI knowledge base; and iii) RFI protection infrastructure, to deal with unintended RFI and jamming, which consists of (a) RFI mitigation capabilities against unintended interference, and (b) a unified framework for the development of jamming/anti-jamming games, which supports comprehensive modeling of SATCOM users and jammer behaviors, as well as the information asymmetry between different players of the game. Based on the game framework, SATCOM jamming/anti-jamming games will be configured and investigated for various scenarios of interest. A conceptual hardware design of a highly adaptive cognitive transceiver is also proposed, which allows highly flexible radio configurations supporting an efficient operation under low SWaP constraints, and hardware in the loop emulation. BENEFIT: The GUARD framework is developed to significantly improve SATCOM system performance in presence of RFI from various sources and of various natures. The proposed GUARD architecture has tremendous applications potential in many military applications. It can be used to protected tactical space communications with dynamic spectrum sharing and interference mitigations. In addition, some relevant Defense Acquisition Programs within DoD are such as WSCE-W/V-band space communications Experiment, PTW MILSATCOM DFARR program, WGS-Wideband Global SATCOM, WIN-T Warfighter Information Network-Tactical, JSTARS Joint Surveillance and Target Attack Radar System Aircraft, JTRS GMR Joint Tactical Radio System Ground Mobile Radio, DCGS-N--Distributed Common Ground Station-Navy, DCGS-X (Air Force), DCGS Army (DCGS-A) system, High Data Rate Airborne Terminal and XG DSA2100, etc. For some of these programs we already have close connections and know considerable program details. The market for military is quite large and IFT has successfully transitioned research prototype for inclusion in DoD contractor research simulations. We can also see commercial application of this project with the numerous concepts being developed. The proposed tool can be used to support commercial applications include disaster management, air traffic control, network defense, the national weather service, physical security systems, law enforcement agencies, emergency control centers, border and coast patrol, pollution monitoring, remote sensing, robotics, medical applications, and global awareness. We have many unique concepts with broad applicability that the market size is hard to estimate. The general tenets of the proposal support all companies, organizations, and products that provide/utilize spectrum access.
Agency: Department of Defense | Branch: Air Force | Program: STTR | Phase: Phase II | Award Amount: 748.64K | Year: 2015
ABSTRACT: In this project, IFT and its academic partner GMU developed an innovative Harness Enhanced Awareness for Radio Systems (HEARS) framework and technical underpinnings for DSA systems operating under conditions of imperfect knowledge, and used the framework to address challenging problems in satellite communication (SATCOM)DSA. As the logical core of the HEARS, Multi-Entity Bayesian Network (MEBN) models for SATCOM were developed and implemented using Netica Bayesian Network (BN) APIs. The developments bring the power of information fusion, probabilistic inference and reasoning for decision making under uncertainties to SATCOM systems, which allows more reliable in-situ decisions under a broader range of scenarios and avoids performance loss. A SATCOM BN Analysis Tool was developed which integrates SATCOM simulation, BN based decision making and 3D visualization. The Phase I effort provided convincing results of proof-of-concept designs that enable further technology development and transition. In Phase II, our main objectives include: i) extend the core SATCOM MEBN to accommodate more DSA scenarios and applications, ii) fully implement the HEARS framework with hardware-in-loop emulation in a realistic Virtual RF Environment for extensive performance evaluation, design optimization and demonstration, and iii) further advance the technologies towards practical applications such as controlling a L-3 SATCOM Modem for space communication. ; BENEFIT: The proposed HEARS framework for dynamic Spectrum Access under uncertainty conditions has tremendous application potential in many military applications. It can be used for protected SATCOM applications with dynamic spectrum sharing and interference mitigations. In addition, it is applicable to relevant Defense Acquisition Programs within DoD such as PTW Protected Tactical Waveform underdevelopment by DFARR, SSN - space surveillance network, SBSS - the Space Based Space Surveillance system, SBIRS - Space-Based Infrared System program, WGS - Wideband Global SATCOM, JSARS - JSPOC Situational Awareness Response System, DCGS-X - Distributed Common Ground System program (Air Force), DCGS-N -Distributed Common Ground Station-Navy, DCGS-A - DCGS Army system. IFT will work with L3 to focus on marketing the resultant technology to their existing Air Force customers. As the first priority, IFT will leverage existing activities IFT has with several Air Force programs that can quickly take advantage of this highly critical technology. This technology could also benefit deep space exploration and other scientific research activities in space research and development. Other potential commercial applications include management of the civilian networks, such as finance, medicine, communications, electric power, nuclear energy, internet service providers, air traffic control, etc.
Agency: Department of Defense | Branch: Air Force | Program: SBIR | Phase: Phase II | Award Amount: 745.78K | Year: 2015
ABSTRACT:The space domain today is becoming increasingly congested. The detection, classification, and tracking of Resident Space Objects (RSO) is critical for space situational awareness. How to best utilize available sensing resources becomes extremely important. The Phase I effort has resulted in a high Performance Computing enabled Distributed Game theoretic Sensor Management software Suite (HEADGT) for RSO detection, classification, and tracking. We obtained promising results which clearly demonstrate that IFTs HEADGT software suite provides innovative and effective game theoretic approach for sensor resource management with consideration of various operational constraints. The developed HEADGT integrates space object classification and tracking, heterogeneous sensor measurements fusion, maneuver detection, collision alert, sensor modeling, game theoretic modeling and solution, hardware implementation, and visualization system. In the phase II project, we will refine, extend, and optimize our Phase I system concept and models to meet the realistic requirements of the Air Force for RSO detection, classification and tracking. In addition, IFT team will 1), extend and tie all the models developed in Phase I using high performance computing enabled implementations, 2), enhance the hardware prototype, 3), enrich interfaces with other SSA testbeds such as Space Fence System.BENEFIT:The proposed HEADGTSM toolbox has tremendous application potential in many military applications. It can be used to defensive counter space mission to protect high value space assets, collision avoidance, detection, tracking, classification space objects. In addition, it is applicable to relevant Defense Acquisition Programs within DoD such as Space Fence System, SSN - space surveillance network, SBSS - the Space Based Space Surveillance system, SBIRS - Space-Based Infrared System program, WGS - Wideband Global SATCOM, JSARS - JSPOC Situational Awareness Response System, DCGS-X - Distributed Common Ground System program (Air Force), DCGS-N -Distributed Common Ground Station-Navy, DCGS-A - DCGS Army system. For some of these programs we already have support and know considerable program details. The market for military applications is quite large and IFT has successfully transitioned research prototypes for inclusion in DoD contractor research simulations. This technology could also benefit deep space exploration and other scientific research activities in space research and development. Other potential commercial applications include monitoring the civilian networks, such as finance, medicine, communications, electric power, nuclear energy, internet service provider, air traffic control, etc. In addition, police and first responders for NASA, US Coast Guard, Department of Homeland Security, multi-layered sensing, disaster assessment, the national weather service, physical security systems, law enforcement agency, emergency control center, border and coast patrol, pollution monitoring, remote sensing and global awareness could be a potential application.