A DRFM system may modify the signal prior to retransmitting which can alter the signature of the false target; adjusting its apparent radar cross section, range, velocity, and angle.
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 Association of Old Crows, written by Sheldon C. Spector, entitled "A Coherent Microwave Memory Using Digital Storage: The Loopless Memory Loop".
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 monopulse radar angular measurement techniques.
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.