THz networks. The military became interested in ultrafast data transfer

THz networks. The military became interested in ultrafast data transfer

The “Let's Talk About Science” rubric addresses the issue of developing ultrafast data transfer technologies. To date, such work is carried out in dozens of universities and research laboratories around the world. The other day, scientists from Brown University (USA) told about their achievements in this direction.


The team of scientists demonstrated a method developed at Brown University that allows digital devices to detect each other in a certain part of space in ultrafast terahertz (THz) networks. These networks are considered to belong to the next generation of data exchange (what follows 5G).

Because of the high frequency, THz waves are capable of transmitting hundreds and thousands of times more data per unit time than the waves that are used in data transmission today (this is a comparison primarily with microwaves). But THz waves do not propagate like microwaves. Terahertz waves come from the source in narrow “channels”, and not across the entire sphere (hemisphere). In this regard, a problem arises in how the router can determine where a particular client device is located in order to accurately direct a signal to it - a THz wave.

Professor Dan Mittlman reports that the so-called leaky waveguide can solve the problem. It allows you to detect the channel at THz frequencies.

An unpressurized waveguide is two metal plates with a gap through which a wave can propagate. One plate has a narrow slot that allows certain wave components to exit. The detection of devices is based on the principle of wave analysis by the angles of their deviation at the output of the waveguide.

Scientists compare this with the color spectrum (rainbow), when each color is a beam of waves with a certain frequency range. From the spectrum, you can learn a lot about objects that emit and absorb radiation.

From the work of scientists:

Imagine a leaky waveguide located on an access point. Depending on where the client device is located relative to the access point, it will see a different color (different wavelength) emerging from the waveguide. It is enough for the client to send a signal back to the access point with the information: “I saw yellow / blue / red (a certain wavelength)”, and now the access point itself will know where the client device is located. After that, she can continue to track him in space.

At the same time, scientists note the presence of problems with this method. The problems are associated with the need to constantly adjust the process when moving the client device.

These developments today concern not only civilian specialists, but also the military. The reason for the military interest is related to the updating of classified information transmission systems, its encoding. For example, we can talk about a new generation of a network-centric intelligence system or military operations - when a unit of time for a successful operation needs to transmit more and more useful information, which, moreover, will be protected from interception or distortion by the enemy. Also of interest is the acceleration of data transmission from military satellites to client devices, including airborne weapons control systems for aircraft, UAVs or warships.

But there is an opinion that in the case of this kind of application, the very leaky waveguide with which they work at Brown University is unlikely to be effective.
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  1. rocket757 April 27 2020 20: 22 New
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    Science, technology does not stand still. There are results, there will be integration, everywhere.
  2. businessv April 27 2020 20: 33 New
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    it is believed that in the case of this kind of application, the very leaky waveguide with which they work at Brown University is unlikely to be effective.
    It immediately seemed that this system would be good for static objects - there would be too many troubles and time consuming with determining the location, this could destroy almost all the advantages of transmission speed.
    1. Bobrick April 28 2020 01: 08 New
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      http://militaryrussia.ru/blog/topic-740.html Р-431АМ - как раз такая радиостанция, правда гигагерцевого дипазона.
      Stationarity is not a problem at all, but the fact that the communication range will be only at the line of sight is a serious limitation.
      1. Bobrick April 28 2020 01: 25 New
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        range, more precisely
  3. Tusv April 27 2020 20: 53 New
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    Oh yo. But the men don’t know. Windows for updating suppresses a disk ce at most do not indulge. Tell us about these scientists in more detail. The desire to tear the skin from them is very persistent. And the Brinanians are towing towers
  4. A. Privalov April 27 2020 20: 58 New
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    As far as I remember, due to the fast attenuation of the signal in the terahertz range
    when distributed in the atmosphere, for the time being, it is possible to use only direct terrestrial communication over a distance of several kilometers.
    He looked into the scientific literature. It is said that somewhere, in some narrowly specialized essays, the results of theoretical calculations are presented, according to which a transmitter output power of several hundred microwatts is sufficient to transmit data over a distance of 1,5 km with an antenna gain of at least 50 dB. And even the experimental results are presented, which showed the possibility of transmitting digital signals at a speed of up to 1 Gb / s over a distance of 1 km. That's all for today. Alas. hi
    1. knn54 April 27 2020 22: 01 New
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      The attenuation of a signal in this range is highly dependent on humidity, which, however, decreases at high altitudes.
      In addition, increased divergence of waves when moving away from the transmitter due to diffraction. need emitters with high directivity.
      The manufacture of THz components is complex and time-consuming today, so the price is sky-high.
    2. orionvitt April 27 2020 23: 39 New
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      Quote: A. Privalov
      He looked into the scientific literature.

      And in the literature it is not accidentally written how they polluted our environment, various kinds of electromagnetic radiation. Moreover, the farther, the greater the frequency, the wavelengths are less. It will soon come to the point that we will live as if the microwave was on. I am not against progress at all, I just need to know the measure. But how, give everyone even greater volumes of information, even greater speeds. For example, as an ordinary user (like all of us, by and large), these terra gigabyte speeds did not fit into FIGs. Areas where similar speeds are required can be counted on the fingers. And even then, for the most part, they are in the field of fundamental science, far from real life. Or, as an option, the notorious "electronic concentration camp", there it will definitely find application.
    3. bk316 April 28 2020 02: 10 New
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      transmit digital signals at speeds up to 1 Gb / s over a distance of 1 km.

      GB / s? 10 at 18 baud? Hand did not flinch?
  5. voyaka uh April 27 2020 21: 20 New
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    Terahertz, if translated into wavelengths - submillimeter waves.
    It seems that far from transmitting, they will die out?
    1. Aviator_ April 27 2020 21: 56 New
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      Well, yes, 1 THz corresponds to a wavelength of 0,3 mm. Deaf, of course.
    2. Practik2012 April 27 2020 22: 07 New
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      Here is the atmospheric attenuation curve

      In the region of 930 GHz, the transparency window, attenuation of 6-7 dB / km. True, it is in clear weather at an altitude of 1 km, it seems, above sea level.
      1. ltc35 April 27 2020 22: 21 New
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        If the transmission medium is the atmosphere, then the game is not worth the candle. Waveguides and in general now create almost unrealistic. And the main question: what will be the antenna at the receiver and transmitter? Data transmission can work in this range only under conditions of direct visibility, and an element base is not expected in the near future due to reaching the size limit of pp transistors based on known materials.
        1. Practik2012 April 27 2020 22: 49 New
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          At Virginia Diodes, the catalog indicates the standard of waveguides WR-0.51 with a cross-section of the waveguide channel 0,13 * 0,065 mm (1400-2200 GHz) with an estimated attenuation of 0,586-0,369 dB / mm. It is understood that a 10 mm waveguide is already 3-6 dB attenuation. But there are oversized waveguides with a different type of wave. There the attenuation can be less by an order of magnitude. And about the elemental base, take a look at wide-gap materials, various nitrides. The same gallium nitride in centimeters already replaced the lamp in terms of output power. For the same Virginia Diodes in the range of 1400-2200 GHz, varactor multipliers in the catalog show powers of 0,5-3 mW. And this is apparently GaAs.
          1. Practik2012 April 27 2020 23: 39 New
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            Not varactor, but varicap
            1. ltc35 April 28 2020 21: 53 New
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              Maybe all the same we are talking about the frequencies of 1,6-2,2 GHz? And most likely these are the clock frequencies of the ZG.
              1. Practik2012 April 29 2020 15: 25 New
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                hi . No, this is the THz range. It uses multiplication by GaAs varicaps on the third harmonica (multiplies from 500-750 GHz). But I mixed up the power output. 0,5-3 mW (at frequencies of 500-750 GHz) is supplied to the input, and at the output we have power with efficiency as shown in the figure.

                That is, the efficiency in the range 1,4-2,2 THz is 0,1-0,6%, therefore the output power is 0,5-18 μW (micro-). I’ll be more careful next time, otherwise it turned out to be too optimistic fellow
  6. Edvid April 27 2020 23: 06 New
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    And on the torsion connection ty..shi..na ..
    1. Banzai April 27 2020 23: 53 New
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      Torso workers are treated right now for free. And you will be cured))))
  7. Banzai April 27 2020 23: 51 New
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    I went to the site. I thought I’ll read the norms of analytics, I’d like to know the sane people opinion ..... But I ended up on the forum of ear-matzo and shit-newspaper. Is it right now everywhere?
  8. Banzai April 28 2020 00: 09 New
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    Comrades, is there anything more or less real in application? Torsion fields and flat earth theory do not offer. Are there any signalmen? There must be a solution.
    1. Bobrick April 28 2020 01: 23 New
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      And what do you need to write?
      Even now there are arsenal of radio relay stations (R-431AM, R-416 and others) that transmit signals over a horizon (two antennas at 20 meters high give a communication range of about 25..30 km and a speed of such a connection of 100 Mbps / with, besides this, they are difficult to detect and suppress with electronic warfare)
      And from the article it is clear that such installations can already be used in a similar way.
      There will be a working installation - a radio station will appear, what else to write.
      1. ltc35 April 28 2020 21: 57 New
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        Here I am about the same. It is painfully unrealistic to offer frequencies for which the atmosphere is already an obstacle.
  9. gridasov April 28 2020 00: 14 New
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    Before talking about the principles of wave propagation in the indicated range, it is necessary to understand how to form such an electronic magnetic pulse and, accordingly, its algorithms, i.e., a generator of such pulses. Naturally, in order to achieve a sufficient signal transmission range, it is necessary to understand what spin is and how to include it in the wave process. therefore, there is no reason to believe that modern knowledge will allow us to master this area
  10. Well done April 28 2020 01: 15 New
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    And in honor of what are these waves suddenly so selective?
  11. KCA
    KCA April 28 2020 04: 27 New
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    What is the point in increasing the volume of transmitted data? Long ago, targets for ICBMs were transmitted in telegraphic mode using the Makhovik ZAS, transmission speed of several hundred bauds, secrecy - almost forever, who needs terabytes per second and why? HD 1080i video transmit? Run copters in a women's bath?
    1. Bobrick April 29 2020 11: 51 New
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      So now they run into video conferencing, and in transferring graphic computer cards with photo reports, and even Wishlist appeared on military smartphones and graphic tablets that work on their Internet.
  12. Amateur April 28 2020 07: 04 New
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    Laser links (an optical analogue of RRL) have existed for about 20 years. The distance between stations is 3-5 km (due to the peculiarities of light distribution, weather conditions and atmospheric pollution). The bandwidth of modern systems is almost the same as for fiber optic links (gigabits / sec).
    Currently, the optical (laser) signal has been successfully transmitted over a distance of several hundred thousand kilometers. In particular, a record achievement in this sense is the reception of a laser signal from the MESSENGER automatic station. The signal from an onboard laser emitter (infrared diode neodymium laser) was successfully received by an earth receiver at a distance of 24 million km. (wiki)