7.3    COMMUNICATING WITH PHOTONS

I agree with what we read in Electronic or Physics Literature that every kind of radiation like radio, TV microwaves, infrared, visible light, ultraviolet, high energy rays and any kind of heat are all “electromagnetic radiation”.

But what must be understood by “electromagnetic radiation” is radiation of photons ("electromagnetic particles").

It is proposed that what any antenna emits or absorb are photons. What actually happen in communications antennas are the photons' emission or absorption phenomena.

Electric Fields in the transmitters produces currents of electrons in the antenna that collide with the atoms, deliver energy to them and so they emit some type of photons by photons' emission.

The receiver antennas absorb that photons and liberate electrons out of the antenna by the photons' absorption phenomena. This produces a net positive charge in the antenna what generates an Electric Field that acts on the receiver circuit.

The frequency of the emitted photons is different from the frequency of the communication signal. What is modulated is the intensity of the radiated photons. The type of photons emitted or absorbed is which can produce photons' absorption or emission effects in the antennas.

There is a DC level of the intensity of the photons that corresponds to an average value of the quantity of photons being emitted. There cannot be negative values for the intensity of photons. The periodic signals of a typical communication modulate the intensity of the photons from zero to a maximum.

The next graphics illustrate the phenomena for both the photons intensity and the respective signal intensity at the antenna terminal.

If we consider a system where reflected photons exist, it can be demonstrated that all the properties of the waves are conserved. The intensity of the reflected photons is added to the direct photons and another wave is achieved. Especially a standing wave pattern can be produced by the photons.

Now, if we consider the possibility of communications by photons two fast questions arises:

QUESTION 1

We may ask then how an alternating signal at the transmitter antenna with symmetric positive and negative values can produce an only positive intensity of photons and how an only positive intensity of photons can produce an alternating electric signal at receiver antenna.

Here we must be careful in what Ground means.

We should consider first that:

No material can have a net negative charge.

Negative charges are produced by electrons and they can only exist in the atomic structure attracted by the positive nucleus of the atoms. The maximum number of electrons that any material can have is that which neutralizes the positive charges of the nucleus. More electrons than this can only be free electrons and they would repel each other out of the material.

Then any material can only be neutral or positive charged.

Our ambient is radiated mainly by the sun and this radiation has a certain spectrum of photons. The sun radiation is vital because it maintains an ambient temperature. At ambient temperature there is an average quantity of photons emitted and received by any material in nature in a dynamical equilibrium. Then the photons' emission and absorption phenomena are always present and any material has its atoms in a certain average level of energy. Depending on the material and the radiation the electrons can occupy different positions in the atom structure but electrons can also be liberated from the atoms if the atoms absorb photons with enough energy and in this case the materials get a net positive charge. If a certain material is positively charged then it has some positive potential relative to a completely neutral one.

It is proposed here that for common metals what we normally intend as “electric ground” is really a positive potential.

We can call it the Ground Level.

This phenomenon is particularly present in electric systems:

At ambient temperature there is an average intensity of photons being emitted and received by the antennas even without signal in them. Many of the photons received (not all) liberate electrons from the atomic neutral structure of the material of the antennas and the wires and all the electric components of the transmitter and the receiver because of a net charge greater than zero in all the elements. The elements are not really neutral at ambient radiation. Then there is an average potential in the antennas and this is the Relative Ground Level at ambient radiation of the antennas. The signals at the transmitter and the receiver can have positive or negative values relative to this Ground Level but they are always positive relative to the Absolute Ground determined by a completely neutral material.

Then we must be careful. We normally measure electric signals relative to the Ground Level and in this case we have negative signals and we may be leaved to the wrong idea that materials could be negatively charged.

At the transmitter antenna whenever a positive signal relative to the Absolute Ground is present at the terminals electrons are attracted into the circuit, a current of them is created in the antenna and they collides with the atoms giving them energy what finally produce an emission of some kind of photons. In this manner photons are modulated by electric signals. Great signals produce high amount of photons emitted, small signals produce little amount of them and only zero signals relative to the Absolute Ground produce no photons at all.

At the receiver antenna the symmetric photons' absorption takes place and electrons are liberated proportionally to the intensity of photons absorbed and this creates a positive net charge of the antenna which finally attracts electrons from the receiver circuit creating a current proportional to the absorbed photons.

It can be argued that if metals are positively charged at ambient temperature then, between themselves, the electric repulsion phenomenon should be normally observed. But it must be considered that the electrons liberated from the metals remains near them and they also enters and leaves the material structure in a dynamical equilibrium. Then also at very small distances metals appears neutral.

QUESTION 2

Another question that may surge if we consider the possibility of communication by photons is why a typical linear antenna needs to have a length equal to λ/4.

To answer this question we must treat the problem of the velocity that electrons travels in an antenna.

The recognized method to measure the velocity of the electrons in a conductor is that based on the Hall Effect. In this method the conductor is submitted to a perpendicular magnetic field so that the electrons are forced to reach one side of the conductor and creating in this manner an electric potential between the sides of the conductor. This potential can be measured with a voltmeter.

With this method a velocity of about centimeters per second is measured. But in the new definition of the Magnetic Field the factor s is present and it makes the field to be null for electrons traveling at c velocity.

We see that with the new theory the method is not valid. For very fast electrons the action of the Magnetic Field is negligible.

With the new theories the electrons can travel at c velocity and it is proposed to consider the possibility that the majority of the electrons in conductors with current are accelerated and travels at c velocity. It must be considered that the electrons travel trough the molecular structure of the metallic conductors and are accelerated by positive protons at very small “atomic” distances when the Electrical Field is very strong between them and the electrons can reach velocity c.

As the electrons moves from the antenna to the circuit and inversely, the signal at the input terminal conductors of the circuit varies.

Let suppose that initially the signal is zero but photons are being received by the antenna so it is getting positively charged and then having a positive relative potential at the terminal extreme.

  The signal in the terminals is initially zero and it will take a quarter of the period T of the signal to reach its maximum positive value. In that interval of time the electrons are attracted from the circuit to the antenna and the first ones have traveled a distance equal to λ/4 if their velocity is c.

In the next λ/4 interval the signal decrements and electrons get into the circuit again.

Then an antenna of length λ/4 corresponds to the maximum number of electrons that can be taken out of the circuit in a quarter of the period of the signal.

This will be the case of a maximum signal detected by the circuit.

If the antenna has a length greater than λ/4 it will be capable to detect signals of other frequencies and more noise is added to the receiver circuit.

Then the optimum length of the arm of the antenna will be λ/4.

A similar reasoning can be applied to the inverse situation when the circuit is more positive than the antenna.

This is the same condition reached by the electromagnetic wave theory and the experience.