"Arny Krueger" writes:

"Bob Cain" wrote in message

Arny Krueger wrote:

While I've got this set up, any other data that anyone would find
interesting?

Many thanks, Arny. Experimentalist that you are, I had a
feeling you were off doing that. :-)

My question is, wouldn't the kind of distortion claimed as
"Doppler" distortion, which is claimed to be FM, have a
continuous harmonic structure around that 4k peak rather
than the discrete one you are seeing?

No, because the modulating frequency is a pure tone/

That's right. Specifically, you will have sidebands at
integer multiples of the modulating frequency, thus the
spectrum will be discrete. The magnitude of the nth sideband
is given by a Bessel function of the first kind, J_n(B), where
B is the amplitude of the modulating signal.

[From Mischa Schwartz's "Information, Transmission, Modulation,
and Noise," 4th ed.]
--
Randy Yates
Sony Ericsson Mobile Communications
Research Triangle Park, NC, USA
, 919-472-1124