This paper describes how a reconfigurable electromagnetic interface (REI) can, at the antenna element level, enhance the affordability and shorten the development lifecycle of platform-based phased arrays. These improvements are enabled by a significant degree of component and process reuse and also by easing the design requirements on phased array common modules. Among the benefits of an REI are: tunable frequency selectivity, tunable polarization selectivity, tunable phase, four times the allowed common module footprint (area), and no balun requirement.
Characterization of GeTe-Based RF Switches under direct optical laser excitation is shown with the ON state DC electrical resistivity and OFF state capacitance. Based on our tightly-coupled dipole array with performance in excess of 4 to 1 bandwidth over wide-scan angle up to 60 degrees, and with in-band rejection capability using reconfigurable baluns, the antenna aperture is shown to exhibit reconfiguration flexibility with the integration of optically-controlled GeTe-Based RF switches.
Phased array systems offer numerous advantages to the modern warfighter in multiple application spaces, including Radar, Electronic Warfare, Signals Intelligence, and Communications. However, a lack of commonality in the underlying technology base for DoD Phased Arrays has led to static systems with long development cycles, slow technology refreshes in response to emerging threats, and expensive, application-specific sub-components. The IMPACT module (Integrated Multi-use Phased Array Common Tile) is a multi-channel, reconfigurable, cost-effective beamformer that provides a common building block for multiple, disparate array applications.
The thermally driven metal insulator transition in vanadium dioxide (VO2) is used to create a low loss millimeter wave switch which operates up to and beyond W-band frequencies. We have built RF switches using vanadium dioxide thin films fabricated within a section of inverted transmission line with integrated on chip heaters to provide local thermal control. On heating the films above the metal insulator transition we obtain record low switch insertion loss of 0.13 dB at 50 GHz and 0.5 dB at 110 GHz. The switch cut-off frequency is high, fc ~ 45 THz, due to the low on state resistance and off state capacitance. We have investigated the device physics of these switches including self-latching of the devices under high RF powers, and demonstrated their integration with silicon germanium RF circuits where the switch heater current sources and control logic are also integrated into the same silicon germanium circuit.
The ability to evolve Military Communication and Information Systems (CIS) effectively and affordably is enhanced by the adoption of open and modular system architectures. However, there are a number of issues with actually achieving these benefits in practice. This paper presents the results of an initial system study into blockers to the achievement of the benefits of open and modular systems. In particular, the study and this paper, focuses on the issues associated with: the rapidly evolving Information and Communications Technology landscape; the commercial approach to the procurement of CIS systems; the evolution of such systems in a safe and secure manner.
Integrated Sensor Architecture (ISA) is designed in response to stovepiped integration approaches. The design, based on the principles of Service Oriented Architectures (SOA) and Open Architectures, addresses the problem of integration, and is not designed for specific sensors or systems. The use of SOA and Open Architecture approaches has led to a flexible, extensible architecture. Using these approaches, and supported with common data formats, open protocol specifications, and Department of Defense Architecture Framework (DoDAF) system architecture documents, an integration-focused architecture has been developed. ISA can help move the Department of Defense (DoD) from costly stovepipe solutions to a more cost-effective plug-and-play design to support interoperability.
Radio frequency products spanning multiple functions have become increasingly critical to the warfighter. Military use
of the electromagnetic spectrum now includes communications, electronic warfare (EW), intelligence, and mission
command systems. Due to the urgent needs of counterinsurgency operations, various quick reaction capabilities (QRCs)
have been fielded to enhance warfighter capability. Although these QRCs were highly successfully in their respective
missions, they were designed independently resulting in significant challenges when integrated on a common platform.
This paper discusses how the Modular Open RF Architecture (MORA) addresses these challenges by defining an open
architecture for multifunction missions that decomposes monolithic radio systems into high-level components with welldefined
functions and interfaces. The functional decomposition maximizes hardware sharing while minimizing added
complexity and cost due to modularization. MORA achieves significant size, weight and power (SWaP) savings by
allowing hardware such as power amplifiers and antennas to be shared across systems. By separating signal conditioning
from the processing that implements the actual radio application, MORA exposes previously inaccessible architecture
points, providing system integrators with the flexibility to insert third-party capabilities to address technical challenges
and emerging requirements.
MORA leverages the Vehicular Integration for Command, Control, Communication, Computers, Intelligence,
Surveillance, and Reconnaissance (C4ISR)/EW Interoperability (VICTORY) framework. This paper concludes by
discussing how MORA, VICTORY and other standards such as OpenVPX are being leveraged by the U.S. Army
Research, Development, and Engineering Command (RDECOM) Communications Electronics Research, Development,
and Engineering Center (CERDEC) to define a converged architecture enabling rapid technology insertion,
interoperability and reduced SWaP.
The Defense Advanced Research Projects Agency (DARPA) is developing a Video Synthetic Aperture Radar (ViSAR) system designed to provide a targeting capability for the AC-130 gunship in conditions where the current electro-optic systems will not perform. By using radar, the gunship’s availability rises from 35% to 72%, as clouds currently obscure the EO/IR camera’s view of the ground. Several technical issues must be addressed in the program in order to be successful. In order to achieve frame rates fast to track maneuvering targets, the radar must operate at frequencies over 170 which requires the development of new electronics. Secondly, as targets move in the FOV of a Synthetic Aperture Radar (SAR) their apparent position is translated in the generated imagery. Thirdly, as the imagery generated is range versus azimuth rather than elevation versus azimuth, tall objects appear to be “laid over” unless corrections are made for the true height of the object imaged. This paper will describe the DARPA program striving to overcome these issues and review the approaches be taken to achieve the imagery required for the close air support mission.