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ABSTRACT: Microwave photonic and carbon nanotube links may appear separately and synergistically in future military antenna systems. As photonic and CNT link performance continues to improve, RF photonics insertion into antenna systems may expand in areas including RF pre-processing and filtering, RF front-end technology, A/D conversion, true time delay (TTD) beam forming network for both manned and unmanned ISR applications.
Avionics, Fiber-Optics and Phototonics Technology Conference, 2009. AVFOP '09. IEEE; 10/2009
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ABSTRACT: Microwave photonic links and RF photonics will appear frequently in military antenna systems. As photonic link performance continues to improve, RF Photonics insertion into antenna systems will expand in areas including RF pre-processing and filtering, RF front-end technology, A/D conversion, photonic switched true time delay (TTD) beam forming networks for intelligence, surveillance and reconnaissance as well as electronic warfare manned and unmanned applications.
Avionics, Fiber-Optics and Photonics Technology Conference, 2008 IEEE; 11/2008
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ABSTRACT: Energy consumption is becoming a more important issue in the United States. High oil prices, volatile political climates, and greater environmental concerns, and awareness to the costs of energy usage have led to an emphasis on conservation. One area where there is increasing research is in increased fuel economy. An area where there are many commercial solutions is hybrid vehicles. As of the end of 2007, over a million hybrid vehicles have been sold worldwide. This widespread adoption has led some to find ways in which to increase hybrid fuel economy. One such means is to augment hybrid vehicles with plug-in technology. Such solutions currently involve people converting commercial hybrid vehicles using inverters, batteries, and reprogrammed computers. These solutions can often increase gas mileage by over 20%. However, it is less clear as to the savings one would achieve economically and environmentally. Here we perform an analysis using the Toyota Prius as a platform.
Systems, Applications and Technology Conference, 2008 IEEE Long Island; 06/2008
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ABSTRACT: Current and future electronic warfare (EW) & intelligence surveillance and reconnaissance (ISR) systems are becoming increasingly more electronically complex with requirements for external antennas and apertures that are susceptible to various sources of electromagnetic interference and compatibility (EMI/EMC). A reduction in EMI may be required in order to ensure interference free operation during active jamming and ISR, as these platforms evolve into more complex, multi-mission ISR networked systems. One of the most difficult EMI/EMC problems that result from integrating many transmitters, receivers and antennas on one platform is cosite EMI. Technologies such as advanced interference cancellation systems, cosite managers, advanced antenna design, and low-loss, multi-port antenna couplers are being investigated to mitigate cosite interference. One type of cosite interference is intermodulation. Intermodulation and intermodulation distortion (IMD) is the result of two or more signals of different frequencies being mixed together, forming additional signals at frequencies that are not, in general, at harmonic frequencies (integer multiples) of either. Sources for intermodulation include amplifiers, mixers, passive devices, antennas structural geometry and nearby objects and selection and corrosion of materials. For antenna systems, a simple approach to this problem is to physically separate the receive antenna from the transmit antenna, on platforms such as aircraft, helicopters, spacecraft, ships, and buildings. However this solution may not be possible due to limited space and other platform constraints. The IMD problem is usually too complex to be accomplished by a single numerical approach because the size of the structure is too large, the material properties and geometries are very complex, the number of parameters are considerable, and range of parameters are very computationally large. Another solution is to develop a cosite interference rejection appro-
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ach to cancel the coupled power from the interfering coupled signal obtained by the receive antenna. This paper will review very basic to more complicated cosite interference phenomena and approaches to minimize these effects.
Systems, Applications and Technology Conference, 2008 IEEE Long Island; 06/2008
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ABSTRACT: Modern avionics have created requirements for the insertion of fiber-optic technologies. Applications, such as fly by light, net-centric warfare, high fidelity sensing and in-flight entertainment find utility in the increased bandwidth of fiber optic networks. In addition, in applications involving standoff jamming (SOJ) and radar sensing, there is a need for electromagnetic interference (EMI) immune systems. In still other systems, there is a drive to decreasing weight, where fiber optics can be a solution. When considering the replacement of electronics with fiber optics in legacy avionics systems, it is sometimes unclear whether fiber-optic technologies will lead to an overall benefit. At times, fiber optics are inserted without a rigorous analysis of the benefits. In this paper, we define some considerations for fiber optics insertion and derive a rubric to serve as a guideline for insertion.
Avionics, Fiber-Optics and Photonics Technology Conference, 2007 IEEE; 11/2007
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ABSTRACT: An enabling technology for next-generation EW systems is an all fiber optic backplane. Fiber optic systems are rapidly evolving and this paper will review the application of fiber optics for aircraft and specifically EW applications.
Avionics, Fiber-Optics and Photonics Technology Conference, 2007 IEEE; 11/2007
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ABSTRACT: The phenomenological study of magnetic, electric and electromagnetic field interactions with barrier structures and materials is important to understand from the standpoint of designing for the effects of stray magnetic and electric fields on sensitive electronic equipment for evolving aircraft applications to advanced sensors and systems for urban warfare. Northrop Grumman integrated systems eastern region (ISER) has developed a world-class, robust and validated electromagnetic environmental effects (E3) modeling and simulation (M&S) capability and has performed preliminary M&S of various barrier structures to gain an initial understanding of the phenomenology which must be used as a systems design tool, to design realistic and meaningful test/validation experiments, as well as to validate experimental results for a range of parametric barrier structural enclosures and architectures. ISER is using fundamental, first principal electromagnetic modeling tools, as well as unique hybrids of these phenomenological descriptions, to accurately describe E, H, and RF propagation through complex media/barrier structures. These M&S tools, coupled with laboratory validation measurements, are being used to establish key metrics and performance parameters of individual as well as networked configurations. This presentation will review very basic to more complicated electromagnetic wave/barrier interactions.
Systems, Applications and Technology Conference, 2007. LISAT 2007. IEEE Long Island; 06/2007
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ABSTRACT: Summary form only given. Curved surface diffraction is a phenomenon that is relevant in many areas of communications such as cellular telephony, Wi-Fi access, and ground and vehicle (e.g., aircraft and naval ships) EMI. We have been characterizing electronic warfare (EW) and information, surveillance and reconnaissance (ISR) platform electromagnetic environmental effects (E3) phenomenology. Some of the approaches to mitigate platform EMI include: (i) isolation to re-scatter surface or traveling waves, (ii) patch or conformal antenna replacement architectures for receiving antennas, (iii) adaptive arrays collocated with the receiving antenna, and (iv) selective placement of magnetic radar absorbing material (MagRAM) to attenuate surface (traveling), specular and diffraction induced scattering. We are performing modeling, simulation and validation experiments aimed at quantifying the effectiveness of selected MagRAM treatments to minimize the effect of electromagnetic interference. This effort is developing a robust materials database to optimize electromagnetic 'attenuation versus MagRAM material type, loading fraction, weight and thickness, and accurately measuring intrinsic properties and bulk specular, surface wave and edge diffraction. This approach is allowing us to quantitatively establish a validated database for future applications. In this regards, we have been measuring RF scattering from several curved surface mockups. To ensure we are measuring the energy diffracted from the curved surface, we have to ensure that the mockup is large enough so that the curved surface diffracted energy is large compared to the energy coming from other paths. To this end, we have designed and fabricated a "universal" curved surface test body. This test body can have its dimensions and degree of curvature parametrically altered and can accommodate various surface treatments for test characterization and comparison with modeling & simulation. Highlights of these efforts,- to quantitatively ascertain levels of isolation, which can be reasonably obtained by localized passive techniques, were discussed.
Systems, Applications and Technology Conference, 2006. LISAT 2006. IEEE Long Island; 06/2006
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Long Island Systems, Applications and Technology, 2005. IEEE Conference; 06/2005
