SITIS Archives - Topic Details
Program:  SBIR
Topic Num:  N102-118 (Navy)
Title:  28GHz-43GHz Nadir/Near-Nadir (~70-90 degrees wrt horizontal) Low Probability of Intercept Radio Frequency Direction Finding/GeoLocation Capability
Research & Technical Areas:  Air Platform, Sensors, Electronics

Acquisition Program:  EP-3E Joint Airborne SIGINT Architecture Mod. Common Config. Prgm-ACAT III
 RESTRICTION ON PERFORMANCE BY FOREIGN CITIZENS (i.e., those holding non-U.S. Passports): This topic is “ITAR Restricted”. The information and materials provided pursuant to or resulting from this topic are restricted under the International Traffic in Arms Regulations (ITAR), 22 CFR Parts 120 - 130, which control the export of defense-related material and services, including the export of sensitive technical data. Foreign Citizens may perform work under an award resulting from this topic only if they hold the “Permanent Resident Card”, or are designated as “Protected Individuals” as defined by 8 U.S.C. 1324b(a)(3). If a proposal for this topic contains participation by a foreign citizen who is not in one of the above two categories, the proposal will be rejected.
  Objective:  Develop a single-platform, 28GHz-43GHz (upper Ka Band) Nadir/Near-Nadir (~70-90 degrees wrt horizontal) Low Probability of Intercept (LPI) Radio Frequency (RF) Direction Finding (DF)//GeoLocation capability for airborne Signals Intelligence/Intelligence, Surveillance, Reconnaissance (SIGINT/ISR) platforms.
  Description:  Departure from traditional airborne “stand-off” SIGINT/ISR mission profiles requires full, lower hemispheric signal intercept and geo-localization including signals emanating very close to vertically below the aircraft, a capability not currently developed or available to tactical aircraft, either at the desired frequencies or against LPI targets. Navy SIGINT/ISR aircraft require small, lightweight, and preferably conformal Radio Frequencies (RF) antennas which efficiently operate in the 28GHz – 43GHz range. A single antenna installation which serves to detect emitters of interest over a wide field-of-view and enable the geo-localization of target emitters using Direction of Arrival (DOA) information provided by the antenna is preferred. Solutions involving traditional Electronic Surveillance Measures (ESM) DF GeoLocation techniques requiring the determination of the locus of multiple lines-of-bearing as the aircraft traverses along a path to provide sufficient bearing spread for an accurate DF impact/GeoLocation is not desired as this technique does not generally produce near-instantaneous geolocation of RF emitters. Technical innovation will be required to design both an antenna and processor that can provide a near-instantaneous geolocation capability based on 3-D (azimuth/elevation, or a pointing vector) DOA information. DOA accuracies of 1 to 3 degrees will be deemed sufficient for proof of concept. DOA accuracy greater than 1-3 degrees is desired, but will be weighed against associated cost and complexity it may introduce to the proposal. Alternatively, other RF geolocation techniques, such as time difference of arrival (TDOA), frequency difference of arrival (FDOA), or high speed, high accuracy DF may be explored, as applicable to LPI signals. Additional processing design innovation is desired to provide a “software defined processing” capability (e.g.: vis-à-vis Field Programmable Gate Array) FPGA-based processing which can be reconfigured to detect and locate signals based on various signal parameters (i.e.: power, frequency, modulation, etc.), and enable alternative signal processing techniques by reloading the processor’s software program, as opposed to replacing subsystem “black boxes” or major sections of the system’s firmware. The following are principal antenna and processor attributes whose relative values will be used to select the most suitable proposals: RF Range/Gain, Field-of-View, DF/GeoLocation accuracy, Processor Software Reconfigurability, External Form Factor, System Weight and Power Requirements.

  PHASE I: Design and demonstrate technical feasibility of desired capability. Define proof-of-concept design elements. Provide preliminary design and analyses to include optimized flight profiles and altitudes.
  PHASE II: Finalize Phase I design. Develop proof-of-concept prototype (breadboard/brassboard) design. Develop modeling simulations of proposed capability. Provide modeling results based on prototype parameters and optimized flight profiles. Demonstrate ability to achieve desired capabilities in laboratory environment using simulators/stimulators, and/or virtual environments.

  PHASE III: Develop prototype capable of being testing in airborne environment using aircraft power and aircraft data/control busses. Demonstrate desired capabilities via field testing or testing in simulated or actual signal environments. Transition developed technology to interested Navy platforms and to interested commercial entities. PRIVATE SECTOR COMMERCIAL POTENTIAL/

  DUAL-USE APPLICATIONS: The Airborne Search and Rescue Services would benefit from a successful outcome of this SBIR topic.

  References:   1. Skolnik, M. (2008). Radar Handbook, 3rd Edition. 2. Antenna Engineering Handbook, Fourth Edition. By John Volakis 3. RF and Digital Signal Processing for Software-Defined Radio: A Multi-Standard Multi-Mode Approach (Paperback) by Tony J. Rouphael 4. Owen, T. (2009). Software Defined Radio Solutions for DF Signal Processing Systems. Spectrum Signal Processing (background/informational paper) http://www.spectrumsignal.com/publications/SDR_solutions_for_DF.pdf 5 Pace, P. E. (2004). Detecting and Classifying Low Probability of Intercept Radar, Artech House, Inc. Boston 6. Pace, P. E. (2000). Advanced Techniques for Digital Receivers, Artech House, Inc., Boston,

Keywords:  Conformal Antenna; NADIR RF-DF/Geolocation; Airborne SIGINT; Software Defined Processor; Ka Band; Low Probability of Intercept

Questions and Answers:
Q: My question is that does the LPI target on the groud has LOS (line of sight)? Thank you.
A: Yes. LPI target would LOS to aircraft.
Q: Can you provide any information about the LPI target, such as carrier frequency, bandwidth, modulation type and so on? Thank you.
A: Do not have a lot of details. Assume a low power coastal radar, centered around the 36GHz range. Suggest reviewing Jane's for similar type radars for details.
Q: The reference for the topic indicates this is for the EP-3 program.
1. Would this also be candidate for the P8 MMA and BAMS UAV?
2. What constraints on antenna separation should be assumed?
3. Is polarization determination also required?
4. To what accuracy?
A: 1. Would this also be candidate for the P8 MMA and BAMS UAV?
- Yes
2. What constraints on antenna separation should be assumed?
- None, but smaller is better
3. Is polarization determination also required?
- No
4. To what accuracy?
- All minimum requirements given in SBIR

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