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ArcticMyst Security by Avery

can harmonics of em cause beat interference?

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Mar 16, 2011
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Could you use a harmonic of a microwave freq, in visible light, to cause beat interference. Eg, using a known peak wavelength of microwave of very low power and a laser at very close not not exact f4 harmonic to set up a beat wave patterns. Then use the pattern to gain information about the low power microwave signal. This is probably hugely flawed but playing with a laser and tuning a guitar the same time, and the idea kinda popped into my head. Thinking specifically CMB

ps just using beat as a placeholder for the type of interference, was thinking with the advances lately it would be possible to use a ccd and an oscilloscope to read patterns in the interference. Not sue about a tunable laser as a harmonic source, as I do not think I can get the lines I need that route using anything I could afford or if its even possible
 
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Benm

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It doesn't sound feasible:

If you're talking about micorwaves, that typically means GHz range, such as used by wifi networks or microwave ovens. It would require harmonics into the range of 500 THz or so to reach the frequency of visible light.

Perhaps the 200.000th harmonic could interact with visible light, but realistically no microwave system will produce any off that in detectable amounts.

It's comparable to how much visible light a wall at room temperature would emit. It certainly does emit some photons in the visible range, but you could find yourself waiting the better part of a day for even one to be observed.
 
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A better way to ask would be if I use signal, that is a the freq of a known microwave emission's harmonic, can they interfere?, and usable data be taken from interference.
 
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The classic beat interference involves two waves of slightly different wavelengths so that their slight differences create a slow-changing amplitude. In the case of the wavelengths you're describing, there are a orders of magnitude differences in the wavelength. Any kind of wave interference would look more like the microwave superimposed on a visible/NIR-wavelength carrier wave.

As Benm said, the harmonics of a microwave wave are not going to make much difference either, especially something like an 4F harmonic.
 
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Thanks once again you two. Have to go back to the post it note and revise my idea. :p
 




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