"Frank's" wrote in message
news:YJhdh.17283$YV4.16290@edtnps89...
wrote in message
ups.com...
It is possible to get nonlinear interactions among electromagnetic
waves in plasmas, but you generally need very large amplitudes to get
nonlinearities to kick in.

I'm guessing that "space modulation" has something to do with multipath
reflections or something; the VOR signal that rotates is going to be
modulated by the buildings, mountains, and so forth around the
transmitter, generally, the "space"

Just a guess; I don't really know anything about VOR.

Dan

Space modulation, in the case of VOR, is produced by a dipole
rotating at 1800 rpm. The rotating dipole pattern produces a
30 Hz amplitude modulation of the VOR omni-directional
pattern. This rotating pattern provides bearing information
to the receiver. The reference 30 Hz is provided by
FM modulation of the omni-directional pattern.

73,

Frank (VE6CB)


I know how a VOR works its the concept of space modulation I dont
understand. How can radiated enery from multiple sources combine in space
and modulate each other. This is as described by the FAA manual. I am
thinking this can nit happen but the modulation takes place only in the
receiver, not out in space as described by the manual.