Thread: Beat signals
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Niles
#6
Mar14-12, 02:13 AM
P: 1,863
Hi

Thanks. I guess we are interested in the power, since that is what we measure. So I get

cos(ωt) . cos(ω+Ω)t = [cos(Ωt) + cos(2ω+Ω)] and
cos(ωt) . cos(ω-Ω)t = [cos(Ωt) + cos(2ω-Ω)].

Adding them and keeping terms at Ω gives cos(Ωt), so I get a nonzero DC-signal. Is the author wrong then?

Best regards,
Niles.