Non-Invasive Radio Frequency System Characterization
Navy SBIR 2019.2 - Topic N192-066
NAVAIR - Ms. Donna Attick - firstname.lastname@example.org
Opens: May 31, 2019 - Closes: July 1, 2019 (8:00 PM ET)
TECHNOLOGY AREA(S): Battlespace
ACQUISITION PROGRAM: PMA231 E-2/C-2 Airborne Tactical Data System
OBJECTIVE: Develop technology to automatically, quickly, and non-invasively characterize Radio Frequency (RF) system performance while minimizing human interaction in order to develop models for electromagnetic interference (EMI) and electronic attack applications.
DESCRIPTION: RF systems represent one of the most critical technology areas for the warfighter today. Given the extreme importance of RF systems, they must perform as intended in a wide variety of environments where adversaries may be attempting to jam or spoof them. The Navy must also ensure that new platforms, networks, and systems are designed in such a way that the performance of our own systems is not degraded due to self- interference. Cosite interference problems cost millions of dollars every year and, in extreme scenarios, loss of life. In addition, by characterizing the performance of enemy RF systems, warfighters gain a great advantage by knowing vulnerabilities of such systems and taking a surgical approach to jamming and spoofing enemy RF systems.
Analysis tools exist that predict EMI between RF systems and vulnerabilities of such systems to electronic warfare (EW). However, these tools rely upon the user to provide either parametric models or measured/engineering data as input for the RF systems and subsystem components. Vendors typically do not provide detailed circuit models or measured data for characterizing RF system performance. Subsequently, one of the biggest challenges with a cosite interference analysis is obtaining high fidelity, broadband characterizations of the transmitting and receiving RF systems. Often, analysts have to make educated guesses or use worst-case assumptions in their analyses, resulting in missing real interference problems or over engineering the solution. This has major implications on time/resource allocations that can result in overly complicated equipment for the warfighter. The Navy also has a great need for characterizing enemy RF systems and identifying vulnerabilities in such systems. While the in-band frequencies and sensitivities of enemy RF systems are generally known, the out-of-band susceptibilities are typically not known.
Finding out-of-band susceptibilities of such systems allows our military to jam enemy systems at frequencies that minimize fratricide and impact to civilian infrastructure.
Manually performing measurements for the various channels and operating modes for a single RF system can take an exorbitant amount of time. In particular, receiver measurements are time consuming due to the wide frequency range over which mixer products and spurious responses can occur. When considering the numerous channels that a single modern receiver can operate over, it is clear that measurements need to be automated and user friendly.
Proposed solutions must be capable of characterizing the performance of receivers with very high accuracy (e.g., 25 kHz bandwidth or less) over a 6 GHz or higher span in a few hours. Further, proposed approaches must have the ability to achieve 140-150 dB of dynamic range in transmitter measurements as the characterization of low amplitude spurious emissions and harmonics is essential for such a measurement system.
PHASE I: Develop a detailed description of the proposed techniques required to characterize both transmitters and receivers through measurement techniques, which should be broadband in nature characterizing not only the in-band performance of the RF systems but also the out-of-band performance. Perform manual testing of sample RF systems to validate and demonstrate proposed techniques. Develop plans for automating measurement techniques through custom software and hardware to be implemented during the Phase II effort.
PHASE II: Develop and demonstrate the automated measurement techniques using custom prototype software and hardware. Ensure that the automated measurement system includes a user interface for setting up a data collection (e.g., type of measurement, background information for the RF system under test) as well as providing feedback to the user as the test is being conducted (e.g., warning messages if the user has specified an erroneous test setting). Perform testing of the measurement system including testing on canonical circuits representing typical RF system architectures.
PHASE III DUAL USE APPLICATIONS: Finalize and integrate the algorithmic approach in commercially available measurement equipment for use by the Department of Defense (DoD), DoD contractors, and the commercial sector.
The techniques are applicable to a very wide range of commercial systems including voice and data communication systems, medical devices, automobiles, and trucks.
1. German, F. and Young, M. “An Automated Measurement System for Cosite Interference Analysis.” 2010 EMC Symposium. https://www.researchgate.net/publication/224218252_An_automated_measurement_system_for_cosite_interference
2. Ku, H., McKinley, M.D., & Kenney, J.S. “Extraction of accurate behavioral models for power amplifiers with memory effects using two-tone measurements".” 2002 IEEE MTT-S International Microwave Symposium Digest (Cat. No.02CH37278), Volume 1, pp. 139-142. https://www.semanticscholar.org/paper/Extraction-of-accurate- behavioral-models-for-power-Ku-Mckinley/eec049f0d7c45041ad3ba34f3a27403460a9d11c
3. Turlington, R. “Behavioral modeling of nonlinear RF and microwave devices.” Artech House Publishers, 1999. http://us.artechhouse.com/Behavioral-Modeling-of-Nonlinear-RF-and-Microwave-Devices-P950.aspx
KEYWORDS: Radio Frequency Systems; Electromagnetic Interference; Automated Measurement; Electromagnetic Compatibility; Unintended Emissions; Microwave Devices