From radio signal to corresponding photons

In summary, the conversation discusses a sine signal sent by a low frequency transmitter at 100 kHz with a sending power of 1 watt and a starting phase of 0. The assumptions made are that the frequency of all photons leaving the transmitter is 100 kHz, the number of photons leaving the transmitter is the same at all points, and the phase of the photons at different points differs. However, this information is not enough to fully describe the signal, as the concept of "photon" can have different meanings in classical and quantum electrodynamics. Therefore, it is necessary to specify which theory is being used before further discussion can take place.
  • #1
somega
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Let's assume the following sine signal sent by a low frequency (100 kHz) transmitter.
I think with the information that the sending power is 1 watt and the starting phase is 0 the signal is fully described.

fffMG_0998.JPG

Are the following assumptions correct?:

1. The frequency of all photons leaving the transmitter at any time is 100 kHz.
2. At all points A, B, C, D, E the number of photons leaving the transmitter are the same (this is the intensity).
3. The phase of the photons leaving the transmitter at points A, B, C, D differ.
 
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  • #2
somega said:
I think with the information that the sending power is 1 watt and the starting phase is 0 the signal is fully described.

If you are using classical electrodynamics, then yes, you're right. But if you are using classical electrodynamics, then the concept of "photon" is meaningless and so are all three of your assumptions.

If you are using quantum electrodynamics, so that the concept of "photon" has meaning (although you still need to specify what meaning you are giving it, since it can have more than one meaning), then the information you give does not fully specify the signal. You need to specify the quantum field state.

So before we can go any further, you need to decide whether you want to use classical electrodynamics or quantum electrodynamics.
 
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1. What is the relationship between radio signals and photons?

Radio signals and photons are both forms of electromagnetic radiation. Radio signals are a type of electromagnetic wave that can be transmitted through space, while photons are the fundamental particles that make up electromagnetic radiation. Radio signals are created by the movement of electrons, which in turn produce photons. Therefore, radio signals and photons are closely related and can be converted into one another.

2. How does a radio signal become a photon?

A radio signal becomes a photon when an electric current flows through a conductor, such as an antenna. This current creates an oscillating magnetic field, which in turn creates an oscillating electric field. These two fields combine to form an electromagnetic wave, which is a stream of photons. The frequency of the radio signal determines the energy and wavelength of the photons produced.

3. How are radio signals and photons used in communication?

Radio signals and photons are used in communication through the process of modulation. In this process, a low-frequency signal, such as a voice or music, is combined with a high-frequency radio carrier signal. This carrier signal is then transmitted through space as radio waves, which are made up of photons. At the receiving end, the radio waves are demodulated, separating the original low-frequency signal from the high-frequency carrier signal, allowing the original signal to be heard or seen.

4. What is the speed of radio signals and photons?

The speed of radio signals and photons is the same, which is the speed of light, approximately 299,792,458 meters per second. This is a fundamental constant of the universe and is the maximum speed at which any form of energy or information can travel. This means that radio signals and photons can travel vast distances through space in a relatively short amount of time.

5. Can radio signals be converted back into photons?

Yes, radio signals can be converted back into photons through the process of demodulation. This process separates the high-frequency carrier signal from the low-frequency signal, which is then amplified and converted into electrical energy. This electrical energy can then be used to produce photons, which can be detected by a receiver and converted back into the original signal, such as sound or images.

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