Can a filter based on the photoelectric effect reduce the noise floor?

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Discussion Overview

The discussion revolves around the potential for a filter based on the photoelectric effect to reduce the noise floor in electronic systems. Participants explore the relationship between frequency interference and noise, particularly in the context of classical and quantum phenomena.

Discussion Character

  • Debate/contested
  • Technical explanation
  • Conceptual clarification

Main Points Raised

  • Some participants suggest that while low-frequency noise is affected by higher frequency sources, it may be possible to block these higher frequencies without impacting the desired signal.
  • Others argue that the photoelectric effect is a quantum phenomenon and may not directly apply to classical filtering methods used in antennas and electronic systems.
  • It is noted that electronic systems commonly utilize filters to manage noise across frequency spectrums, allowing for the isolation of desired signals.
  • Participants mention that strong transmissions can raise the noise floor due to spectral leakage and that non-linear systems often involve mixing, which complicates noise characteristics.
  • Some contributions emphasize that the noise floor typically arises from thermodynamic processes and has a broad emission spectrum, rather than from strong transmissions alone.
  • There is a suggestion that traditional filters may not effectively remove noise created by interference patterns, leading to the exploration of alternative filtering methods based on the photoelectric effect.
  • A later reply indicates a need for clearer mathematical explanations to better articulate the concepts being discussed.

Areas of Agreement / Disagreement

Participants express differing views on the applicability of the photoelectric effect to filtering noise in electronic systems, with no consensus reached on the effectiveness or feasibility of such an approach.

Contextual Notes

Some participants highlight the complexity of noise characteristics in both linear and non-linear systems, noting that interference phenomena complicate the use of traditional filters. There are also references to specific mathematical concepts and tools that may aid in understanding the discussion.

danielhaish
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TL;DR
According to the photoelectric effect low frequency em can't be observed by electrons in the atom , and the noise floor is effected by the frequency dense. Therefore if you signal is in low frequency the noise of higher frequencies won't effect it.
Assume you transmitted in low frequency the floor noise would still be effected by other frequencies due interference. But is it possible to reduce the noise created by higher frequency sources by blocking them in a way that won't block the photons transmitted by your source . So even tho by regular antenna you would normally observe the noise as being in low frequency even tho it only a result of higher frequency being create noise in lower frequency due interference
 
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You seem to be mixing up concepts that are unrelated. The photoelectric effect is a quantum phenomenon while antennas, signals and filters are classical.
 
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marcusl said:
You seem to be mixing up concepts that are unrelated. The photoelectric effect is a quantum phenomenon while antennas, signals and filters are classical.
True but if it was somehow possible build a filter that based on such an effect instead of escalation in a conductor you could isolate the effect of other frequency on you signal
 
Do you have a specific question?
 
danielhaish said:
True but if it was somehow possible build a filter that based on such an effect instead of escalation in a conductor you could isolate the effect of other frequency on you signal
This is done ALL THE TIME in electronic systems. Really, ALL THE TIME. Noise has a frequency spectrum. We use filters to only measure the frequencies we are interested in. This is why when you tune in a radio station you don't also get the nearby (in frequency space) station as noise. A huge part of virtually every electronic circuit design task is keeping the stuff you want and getting rid of the stuff you don't want.

Maybe spend a bit of time learning about radios, spectrum analyzers, Fourier Transforms, lock-in amplifiers, etc. Start with Fourier Transforms if you're ready for that math.
 
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DaveE said:
This is done ALL THE TIME in electronic systems. Really, ALL THE TIME. Noise has a frequency spectrum. We use filters to only measure the frequencies we are interested in. This is why when you tune in a radio station you don't also get the nearby (in frequency space) station as noise. A huge part of virtually every electronic circuit design task is keeping the stuff you want and getting rid of the stuff you don't want.

Maybe spend a bit of time learning about radios, spectrum analyzers, Fourier Transforms, spectrum analyzers, lock-in amplifiers, etc. Start with Fourier Transforms if you're ready for that math.
The point is that there is a noise floor effected by other frequencies for isntance strong transmission in low frequency can raise the entire noise floor due spectral leakage
 
danielhaish said:
The point is that there is a noise floor effected by other frequencies for isntance strong transmission in low frequency can raise the entire noise floor due spectral leakage
Yes, in a non-linear systems mixing happens. Still, the noise at the locations of interest has a defined spectral content.

This is why non-linear subsystems, like mixers, samplers, power amps, etc. are nearly always accompanied by filters

The "noise floor" usually isn't a strong transmission. IRL, strong transmissions usually have a high spectral content and will create identifiable mixing products. The noise floor is usually from more thermodynamic processes with a broad emission spectrum and limited power at any single frequency; like black body radiation, white noise, 1/f noise, shot noise, etc. You'll see this when you reduce the bandwidth of your spectrum analyzer (or not). This is why synchronous detection (like with a lock-in amplifier) is so effective. There is a bit of semantics here. The noise in your system is what it is, you can call it a noise floor if you want. It likely comes from several processes.
 
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DaveE said:
Yes, in a non-linear systems mixing happens. Still, the noise at the locations of interest has a defined spectral content.

This is why non-linear subsystems, like mixers, samplers, power amps, etc. are nearly always accompanied by filters

The "noise floor" usually isn't a strong transmission. IRL, strong transmissions usually have a high spectral content and will create identifiable mixing products. The noise floor is usually from more thermodynamic processes with a broad emission spectrum and limited power at any single frequency; like black body radiation, white noise, 1/f noise, shot noise, etc. You'll see this when you reduce the bandwidth of your spectrum analyzer (or not). This is why synchronous detection (like with a lock-in amplifier) is so effective. There is a bit of semantics here. The noise in your system is what it is, you can call it a noise floor if you want. It likely comes from several processes.
What I mean is that also in linear systems the frequency floor is effected by low frequency component due phenomenas such Low-Frequency Modulation and other phenomena caused by interference .regular filters follow superposition which means they wont be able to remove the noise crested by interference pattern with other frequencies. But I was thinking to filter those frequencies from mixed signal by using effect that requires photons to be in spesfic frequency such as the photoelectric effect
 
danielhaish said:
What I mean is that also in linear systems the frequency floor is effected by low frequency component due phenomenas such Low-Frequency Modulation and other phenomena caused by interference .regular filters follow superposition which means they wont be able to remove the noise crested by interference pattern with other frequencies. But I was thinking to filter those frequencies from mixed signal by using effect that requires photons to be in spesfic frequency such as the photoelectric effect
Okay, due to the language barrier here in your posts, you really need to start posting the mathematics behind what you are saying. Your words are just a jumble right now, so hopefully you can use math instead to explain your question. I will send you a DM with tips on how to post your math using LaTeX.
 
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