Multi-Channel Airborne
Bistatic Radar Data
Collection and Analysis
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James Arnts and
David Fenner
Northrop Grumman
Corporation
Baltimore, MD 21230 |
Lee Moyer and
Douglas Page
Technology Service Corporation
Trumbull, CT 06611 |
Ralph Kohler and
Mike Little
Rome Laboratory
Rome, NY 13441-4514 |
Abstract A bistatic radar concept has been postulated as an approach for extending the
surveillance range against low observable targets. This advanced surveillance concept
would employ a receive-only radar on a UAV operating with existing radar systems such as
the E-3 AWACS. The receive-only system would fly closer to the FEBA and therefore have a
signal-to-noise advantage over the long stand-off range monostatic system. This advantage,
however, comes with a penalty in that it must operate in a significantly more complex
clutter environment. Bistatic radar data was acquired for Rome Laboratory using the
multi-channel LBand MCARM system as the receiver and the Tethered Aerostat Radar System
(TARS) at Horseshoe Beach, FL as the transmitter. The primary goal of the test was to
emulate the advanced bistatic surveillance concept operating with either a high PRF or low
PRF waveform in test geometries which produced both pseudo monostatic, as well as wide
bistatic angle geometries. A Moving-Target Simulator (MTS) was located in the test scene.
The MTS emulated targets having various Doppler frequencies and amplitudes and which fell
within the ground clutter spectrum. The acquired bistatic MCARM data was processed by both
conventional (i.e., MTI and Doppler filtering) and Space-Time Adaptive Processing (STAP)
techniques. The STAP concepts included both pre-Doppler and postDoppler algorithms. A
comparison was made to determine the optimal allocation of the available
degrees-of-freedom in time, azimuth, and elevation for the STAP algorithms. The MTS
provided calibrated Doppler tones from which a quantitative assessment of the algorithms'
performance could be made. It was shown that a significant improvement in the
signal-to-clutter ratio could be achieved under stressing clutter conditions.
Multi-channel data which was taken in 1995 and which is available for developing STAP
algorithms for advanced bistatic systems will be covered. Preliminary results obtained by
applying several STAP algorithms will also be presented.
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