189:: The DRFM digitizes the received signal and stores a coherent copy in digital memory. As needed, the signal is replicated and retransmitted. Being a coherent representation of the original signal, the transmitting radar will not be able to distinguish it from other legitimate signals it receives and processes as targets. As the signal is stored in memory, it can be used to create false targets both behind (reactive jamming) and ahead of (predictive jamming) the target intended for protection. Slight variations in frequency can be made to create Doppler (velocity) errors in the victim receiver as well. DRFM can also be used to create distorted phase-fronts at the victim receive antenna which is essential for countering
222:. This type of testing reduces the cost of development, for example, expensive initial flight trials for airborne radars can now be moved to the laboratory. The radar can be tested either through direct coupling, or through air coupling with antennas. Testing the radar in a closed loop HWIL environment with a DRFM allows test case scenarios to be simulated that covers a larger number of test parameters than would be possible in open-air test ranges.
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degradation caused by continuously cycling the energy through a front-end amplifier which allows for greater range errors for reactive jamming and allows for predictive jamming. A DRFM system may modify the signal prior to retransmitting which can alter the signature of the false target; adjusting its apparent
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necessary to adequately represent the signal, then reconstruct that RF signal when required. The most significant aspect of DRFM is that as a digital "duplicate" of the received signal, it is coherent with the source of the received signal. As opposed to analog "memory loops", there is no signal
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JJ. Strydom, E. Pienaar, JE. Cillers and K. Olivier, "Advances in the realtime simulation of synthetic clutter for radar testing and evaluation," 47th Annual AOC International
Symposium and Convention, Atlanta, Georgia, USA, 3–7 October 2010
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JJ. Strydom and JE. Cillers, "Advances in the testing and evaluation of airborne radar through realtime simulation of synthetic clutter," 48th Annual AOC International
Symposium and Convention, Washington, DC, USA, 13–16 November 2011
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The earliest reference to a digital means of storage of RF pulse signals is an article in the Jan/Feb 1975 issue of
Electronic Warfare, a publication of the
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A DRFM system is designed to digitize an incoming RF input signal at a
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Electronic method for digitally capturing and retransmitting RF signals
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187:An example of the application of DRFM in jammers
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