On January 12, IARPA posted a broad agency announcement (BAA) covering phases 2 and 3 of its HFGeo program. Proposals are due by February 20, 2015. Interested contractors should submit any questions by January 29, 2015.
High Frequency (HF) communications systems are in widespread use around the world. They are useful for both Line of Sight (LOS) and beyond-LOS communications links. Precise location of HF transmitters that use the ionosphere for long-range communications is challenging because of the wide variety of natural and anthropogenic noise sources present in this band, ionospheric variations, Faraday rotation, multipath, and multi-mode components arriving from different directions in azimuth and elevation. Even more challenging are the rapid and severe changes in the ionosphere arising from climatic and other sources.
The HFGeo Program aims to dramatically improve the ability to detect and geolocate HF emitters. Phase 1 of the program addressed technical innovations to accomplish this objective including 1) the ability to accurately resolve multiple angles-of-arrival and polarization states through novel antenna concepts; 2) the ability to enhance signal-to-noise ratio and signal detection through the use of multi-dimensional adaptive signal processing; and 3) the ability to accurately determine the dynamic state of the ionosphere. These components were addressed in two prior solicitations, IARPA-BAA-11-07 and IARPA-BAA-12-04.
Phase 2 includes system integration of these innovations followed by a non-real-time field test. Phase 3 will be real-time implementation and demonstration with field testing. Phase 2 will be 18 months and Phase 3 will be 15 months in duration. Phase 2 provides the transition from the key technologies of Phase 1 to the development of a prototype system of hardware and off-line signal processing for use in initial field tests with surrogate targets. Phase 3 will implement real-time signal processing, incorporate signal processing enhancements, and test against realistic targets in realistic environments. If successful, HFGeo will deliver rigorously tested technology capable of accurately geolocating HF sources.
Full information is available here.