Remote Sensing, Algorithms, and Inexpensive Space Sensors

Period of Performance: 08/07/1997 - 02/07/1998


Phase 1 STTR

Recipient Firm

Quadrant Engineering, Inc.
107 Sunderland Road
Amherst, MA 01002
Principal Investigator
Firm POC

Research Institution

University of Massachusetts Lowell
1 University Ave.
Lowell, MA 01854
Institution POC

Research Topics


In this proposal Quadrant Engineering Inc. and its academic partner, the University of Massachusetts, seek STTR funding to develop an airborne Dual-Beam Interferometer for measurement and mapping of the ocean surface current vector in the littoral zone. The proposed instrument, initially targeted for small aircraft, will be capable of estimating the surface current vector with a single pass of the aircraft. The proposed technique uses a aft-squinted beam. The forward motion of the aircraft imparts different Doppler shifts to each beam, allowing them to be separated during signal processing. The two dual-beam antennas are separated in the along-track direction, allowing interferometric estimates of surface Doppler velocity along both the fore and aft beams. The two surface Doppler velocity estimates are combined to for a vector surface current estimate. The proposed technique will exploit limited synthetic aperture processing within the constraints dictated by the ocean surface coherence time. Simple "unfocused SAR" processing is sufficient to resolve the surface to a few tens of meters in the along-track direction from nominal flight altitudes.