55 channels on one carrier frequency: breakthrough of the Swedish-Italian group of scientists
55 - this is the number of channels on one carrier frequency promised by the scientists of the University of Padua ( Università degli Studi di Padova ), Italy, and the laboratories of Angstrem ( Ångströmlaboratoriet ), Sweden, they confirmed their words with the first non-laboratory experiment that was revealed to the world on June 24, 2011 . And the first of March appeared a scientific article with its detailed explanation.
Venetian scientists experimented as follows: on the island of San Giorgio and on the balcony of the Palazzo Ducale, they installed two antennas - the distance between them was 442 meters. Further, physicists transmitted two different sound tones - 1000 and 400 Hz with the help of two identical Wi-Fi-FM transmitters with equal power of two Wat, but most importantly - the signal was transmitted on one carrier frequency - 2.414 GHz.
What's the secret? In the waves. More precisely in how much they are twisted. An electromagnetic wave, in addition to such characteristics as frequency, amplitude, phase ... also has an orbital angular coefficient (OAM). In essence, this is a wavefront shape that spins along the axis of propagation, like average Soviet macaroni around its own axis.
OAM has two main characteristics: the direction (on / against the clock) and the degree of torsion, it was the latter that became the culprit of the Venetian miracle. During the experiment, one wave was zero OAM, and the second was “twisted”.
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The logical question is: how many of these "twisted" signals can a single wave withstand? Theoretically - as much as necessary. In practice, scientists call the interval from -5 to 5: “Within reasonable economic limits, you can use the state of the orbital moment from -5 to +5, including the untwisted wave. In this case, we can have 11 channels on the same frequency band. If you still use multiplexing , as in digital TV, on each of them, then you can get 55 channels in the same frequency range, ”says Fabrizio Tamburini, the leading expert of the project.
PhysOrg.com has already converted the discovery into an astronomical plane, with their help the portal suggests investigating a black hole located in the center of the Galaxy, which generates similarly swirling waves.
As for the Italians, as desperate descendants of the creators of gladiatorial battles, they could not help introducing pathos and entertainment to the described experiment, when the signal was received, a rifle shot sounded - in honor of the first radio program by Guglielmo Marconi in 1895, and on the walls of the Ducale Palazzo “Segnale ricevuto” was highlighted (signal received).
Venetian scientists experimented as follows: on the island of San Giorgio and on the balcony of the Palazzo Ducale, they installed two antennas - the distance between them was 442 meters. Further, physicists transmitted two different sound tones - 1000 and 400 Hz with the help of two identical Wi-Fi-FM transmitters with equal power of two Wat, but most importantly - the signal was transmitted on one carrier frequency - 2.414 GHz.
What's the secret? In the waves. More precisely in how much they are twisted. An electromagnetic wave, in addition to such characteristics as frequency, amplitude, phase ... also has an orbital angular coefficient (OAM). In essence, this is a wavefront shape that spins along the axis of propagation, like average Soviet macaroni around its own axis.
OAM has two main characteristics: the direction (on / against the clock) and the degree of torsion, it was the latter that became the culprit of the Venetian miracle. During the experiment, one wave was zero OAM, and the second was “twisted”.
')
The logical question is: how many of these "twisted" signals can a single wave withstand? Theoretically - as much as necessary. In practice, scientists call the interval from -5 to 5: “Within reasonable economic limits, you can use the state of the orbital moment from -5 to +5, including the untwisted wave. In this case, we can have 11 channels on the same frequency band. If you still use multiplexing , as in digital TV, on each of them, then you can get 55 channels in the same frequency range, ”says Fabrizio Tamburini, the leading expert of the project.
PhysOrg.com has already converted the discovery into an astronomical plane, with their help the portal suggests investigating a black hole located in the center of the Galaxy, which generates similarly swirling waves.
As for the Italians, as desperate descendants of the creators of gladiatorial battles, they could not help introducing pathos and entertainment to the described experiment, when the signal was received, a rifle shot sounded - in honor of the first radio program by Guglielmo Marconi in 1895, and on the walls of the Ducale Palazzo “Segnale ricevuto” was highlighted (signal received).
Source: https://habr.com/ru/post/139652/
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