Amendment 4

Amendment 0004 – September 30, 2025
NRL BAA Announcement #N00173-24-S-BA01
Long Range Broad Agency Announcement (BAA) for Basic and Applied Scientific Research
The purpose of this amendment is to extend the due date for acceptance of White Papers and revise Appendix 1 in it’s entirety as follows:

APPENDIX 1 – RESEARCH DESCRIPTION - SUMMARY TOPICS

II. Detailed information about the funding opportunity
The Naval Research Laboratory (NRL) is the Navy's corporate laboratory. NRL conducts basic and applied research for the Navy in a variety of scientific and technical disciplines. The basic research program is driven by perceptions about future requirements of the Navy. The Navy's operational effectiveness depends on its ability to keep pace with rapidly developing technologies. NRL contributes to this requirement by conducting research in the following areas, organized into NRL'S three research directorates and Naval Center for Space Technology:
Systems Directorate Code 5000
Materials Science and Component Technology Directorate Code 6000 Ocean and Atmospheric Science and Technology Directorate Code 7000 Naval Center for Space Technology Code 8000

A. SYSTEMS DIRECTORATE - CODE 5000

53-24-01 - HIGH FREQUENCY RADAR

The Systems Section of the Advanced Radar Branch of the Naval Research Laboratory (NRL) conducts research and development in concepts and techniques for using high frequency (3 MHz to 30 MHz) radar to meet U.S. Navy mission requirements. Focus is on high frequency electromagnetic wave propagation and scattering (sky-wave and surface wave), radar system performance forecasting, radar system testing, radar data transfer, signal processing methodologies, spread Doppler clutter mitigation and use of the radar return to classify targets. Additional information on this new type of radar is available in the "Radar Handbook", 3rd edition, edited by M. I. Skolnik, pp. 20.1 – 20.83, McGraw-Hill, 2008 and in “Applications of high-frequency radar,” Radio Science, Vol. 33, No. 4, Pages 1045-1054, July-August 1998. Address White Papers (WP) to [email protected]. Allow one month before requesting confirmation of receipt of WP, if confirmation is desired. Substantive contact should not take place prior to evaluation of a WP by NRL. If necessary, NRL will initiate substantive contact.

53-24-01C - HIGH FREQUENCY RADAR (CLASSIFIED)

The Systems Section of the Advanced Radar Branch of the Naval Research Laboratory (NRL) conducts research and development in concepts and techniques for using high frequency (3 MHz