We always called the antenna an NVIR (near vertical
incidence radiator) antenna, and the mode was NVIS (near
vertical incidence skywave).
It certainly isn't new. The first I heard of it was in the
60's when I first got licensed.
Tuning the reflector 5% longer than resonance is largely a
myth that I see repeated quite often, as is the alleged S/N
improvement with really low heights (although at times that
can work).
What you really need is several low counterpoise wires that
can just lay on the earth parallel with the antenna and
generally longer than the antenna. I suppose making a
vertical yagi would work, but not with the reflector a few
feet above earth. At that height earth to reflector coupling
would make tuning as a reflector unlikely.
The idea is to minimize earth losses, which dominate low
antennas. This is done by providing an alternate path for
currents. Contrary to rumor, improving conductivity or
adding a reflector does NOT suppress low angles. It simply
makes the entire system more efficient with very little
pattern change. Without a significant pattern change, there
can be no signal to noise change.
73 Tom
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