N242-086 TITLE: All-Aspect Maritime Automatic Target Recognition

OUSD (R&E) CRITICAL TECHNOLOGY AREA(S): Advanced Computing and Software; Integrated Network Systems-of-Systems; Integrated Sensing and Cyber

The technology within this topic is restricted under the International Traffic in Arms Regulation (ITAR), 22 CFR Parts 120-130, which controls the export and import of defense-related material and services, including export of sensitive technical data, or the Export Administration Regulation (EAR), 15 CFR Parts 730-774, which controls dual use items. Offerors must disclose any proposed use of foreign nationals (FNs), their country(ies) of origin, the type of visa or work permit possessed, and the statement of work (SOW) tasks intended for accomplishment by the FN(s) in accordance with the Announcement. Offerors are advised foreign nationals proposed to perform on this topic may be restricted due to the technical data under US Export Control Laws.

OBJECTIVE: Develop a method to exploit the unique characteristics of large shipboard radar antenna systems to classify combatants at long range regardless of the aspect angle.

DESCRIPTION: Inverse Synthetic Aperture Radar (ISAR) is the primary means to classify ships from airborne platforms from hundreds of kilometers away. ISAR images are generated by the ship’s rotation around any of the three principal axes. In order to form an ISAR image the Navy requires that any relative motion between the airborne radar and the ship be compensated for, with only the rotation of the ship on the ocean remaining. This is generally done by tracking a point, or multiple points, on the ship that provides a consistent, strong radar return. The resulting range-Doppler image is most informative when the viewing angle is along the length of the ship since features that inform classification are separated in range. If the ship is broadside relative to the radar, then there will be very little range extent, and a mostly range-unresolved range-Doppler image will be produced making classification more difficult or impossible. Reorienting the aircraft to obtain a more favorable viewing geometry can be time consuming, or given airspace restrictions, impossible. However, ISAR has the ability to detect a rotating object and estimate its physical properties regardless of the view geometry (within reason), as long as the rotating structure is observable. Typically, these rotating objects observed on ships are radar antennas. For commercial and non-combatant ships these radar antennas are almost exclusively marine navigation radar such as those produced by Furuno. While combatants also utilize similar navigation radars with comparable antennas, the mission demands of combatants require much larger antennas to service powerful surface or air search radar systems. Some combatants utilize fixed active electronically scanned arrays (AESAs). However, a significant percentage of combatants have large rotating reflector antennas or rotating AESAs. Exploitation of the ISAR return from a rotating antenna can provide information on its position on the ship, its rotation rate, the width of the antenna structure that is rotating and in many instances information on the detailed configuration of the antenna system and pedestal.

ISAR capable radar systems on U.S. Navy aircraft may have many hundreds to several thousand ships under track when operating in dense operational environments such as areas of the western Pacific Ocean. Classifying those ships, particularly when full trust cannot be placed on ship Automatic Identification System (AIS) broadcasts, requires high levels of automation, advanced radar techniques, and operator aids. Still, all of this works best when favorable near-bow or near-stern viewing geometry exists. This SBIR topics seeks to open the viewing geometry to enable probable combatant level classification, or if the antenna structure ISAR signature is sufficiently unique to a ship class, to achieve fine naval-level classification. Aspect independent classification, even at the probable combatant level is extremely valuable as it informs mission execution priorities and planning for ISAR imaging when more favorable viewing geometry exists.

Three critical issues must be addressed in this research. The first is demonstrating the level of ship type separability that rotator exploitation information will provide. Second, identifying additional ISAR-based features in rotator and fixed hard-body returns that supplement the features described in the preceding paragraphs at near-broadside viewing geometries. Finally, sourcing and cataloging a feature database to support classification.

Work produced in Phase II may become classified. Note: The prospective contractor(s) must be U.S. owned and operated with no foreign influence as defined by 32 U.S.C. § 2004.20 et seq., National Industrial Security Program Executive Agent and Operating Manual, unless acceptable mitigating procedures can and have been implemented and approved by the Defense Counterintelligence and Security Agency (DCSA) formerly Defense Security Service (DSS). The selected contractor must be able to acquire and maintain a secret level facility and Personnel Security Clearances. This will allow contractor personnel to perform on advanced phases of this project as set forth by DCSA and NAVAIR in order to gain access to classified information pertaining to the national defense of the United States and its allies; this will be an inherent requirement. The selected company will be required to safeguard classified material during the advanced phases of this contract IAW the National Industrial Security Program Operating Manual (NISPOM), which can be found at Title 32, Part 2004.20 of the Code of Federal Regulations.

PHASE I: Develop, design, and evaluate ship separability using ISAR-based rotator exploitation in both general terms, and for the range of combatants of the Pacific Rim nations. Assess additional features, which might supplement primary rotator features and other hard-body features at near-broadside view geometries. Develop plans to complete the exploitation tool set in Phase II that will address the exploitation chain from feature database development through exploitation and classification support. The Phase I effort will include prototype plans to be developed under Phase II.

PHASE II: Develop the complete near-broadside exploitation tool set whose general approach was defined in Phase I. Work with the Navy to conduct a comprehensive evaluation using existing ISAR image libraries.

Work in Phase II may become classified. Please see note in Description paragraph.

PHASE III DUAL USE APPLICATIONS: Integrate the near-broadside exploitation tool set with an ISAR capable radar and demonstrate its effectiveness using live data.

Identification of maritime traffic is also important to civilian and private organizations that are responsible for scheduling and monitoring that traffic, especially in heavily congested areas. Expanding the fields of view from which quality images can be collected simplifies the problem. Another scientifically interesting and compelling application of ISAR is deep space imaging of asteroids.

REFERENCES:

1. Chen, V. C.; Miceli, W. J. and Himed, B. "Micro-Doppler analysis in ISAR-review and perspectives." 2009 International Radar Conference "Surveillance for a Safer World" (RADAR 2009), Bordeaux, France, pp. 1-6. https://ieeexplore.ieee.org/abstract/document/5438505
2. Kurowska, A. "The preliminary survey of ship recognition algorithms using ISAR images." 2016 17th International Radar Symposium (IRS), May 2016, pp. 1-4. https://doi.org/10.1109/IRS.2016.7497261
3. "National Industrial Security Program Executive Agent and Operating Manual (NISP), 32 U.S.C. § 2004.20 et seq. (1993)." https://www.ecfr.gov/current/title-32/subtitle-B/chapter-XX/part-2004

KEYWORDS: Inverse Synthetic Aperture Radar; ISAR; Radar; Doppler; Maritime; Identification; Classification

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