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UK Scientists Claim 1Tbps Data Speed Via Experimental 5G Technology

Posted by timothy on from the hefty-overages dept.

Mark.JUK writes A team of Scientists working at the University of Surrey in England claim to have achieved, via an experimental lab test, performance of 1Tbps (Terabit per second) over their candidate for a future 5G Mobile Broadband technology. Sadly the specifics of the test are somewhat unclear, although it's claimed that the performance was delivered by using 100MHz of radio spectrum bandwidth over a distance of 100 metres. The team, which forms part of the UK Government's 5G Innovation Centre, is supported by most of the country's major mobile operators as well as BT, Samsung, Fujitsu, Huawei, the BBC and various other big names in telecoms, media and mobile infrastructure. Apparently the plan is to take the technology outside of the lab for testing between 2016 and 2017, which would be followed by a public demo in early 2018. In the meantime 5G solutions are still being developed, with most in the early experimental stages, by various different teams around the world. Few anticipate a commercial deployment happening before 2020 and we're still a long way from even defining the necessary standard.

71 comments

  1. That's Your 2GB cap in 0.9375 seconds by Shakrai · · Score: 5, Insightful

    Not counting TCP and other protocol overhead of course.....

    --
    I want peace on earth and goodwill toward man.
    We are the United States Government! We don't do that sort of thing.
    1. Re: That's Your 2GB cap in 0.9375 seconds by Anonymous Coward · · Score: 0

      Isn't this is about a wireless tower serving a hundred thousand devices a slice of the bandwidth, not so much about a phone with a huge bill ?

    2. Re:That's Your 2GB cap in 0.9375 seconds by Penguinisto · · Score: 1

      Please. Once Verizon gets done lobbying for a redefinition of "5G", you'd be lucky to see a 10% increase in bandwidth from 4G.

      --
      Quo usque tandem abutere, Nimbus, patientia nostra?
  2. Modulation by ickleberry · · Score: 1

    Any newselberries on what kind of modulation is used? TFA doesn't state much apart from 'MIMO'

    1. Re:Modulation by Shakrai · · Score: 1

      Any newselberries on what kind of modulation is used?

      Morse code? ;)

      --
      I want peace on earth and goodwill toward man.
      We are the United States Government! We don't do that sort of thing.
    2. Re: Modulation by Anonymous Coward · · Score: 0

      That seems dubious..would have to be 10kbits / hz

    3. Re: Modulation by Anonymous Coward · · Score: 0

      It is possible with a MIMO system with a really large number of antennas. Of course the streams will no longer be orthogonal, but you still gain. If the environment is rich in reflections this seems theoretically plausible. Doing it in practive is a major achievement.

    4. Re: Modulation by Anonymous Coward · · Score: 0

      I would imagine it is just OFDM but with a lot of tricks to get it running that fast and to deal with all the issues that would normally reduce the Eb/No from theoretical. Or just a really powerful transmitter and terrible range.

    5. Re: Modulation by Marginal+Coward · · Score: 1

      I would imagine it is just OFDM but with a lot of tricks to get it running that fast and to deal with all the issues that would normally reduce the Eb/No from theoretical. Or just a really powerful transmitter and terrible range.

      To expand on that a little, if they tell us about the bit rate (1 Tbs) and the bandwidth (100 MHz) but don't tell us about the power and noise involved (Eb/No), this isn't necessarily heading towards becoming a practical system. Specifically, cell phones don't have unlimited power to devote to transmitting data, and even cell towers have power limits.

      The fact that this was done "over a distance of 100 metres" is telling. Try doing the same thing in a real-world setup with strictly limited transmit/receive power, over a substantial distance, in a noisy environment, with multipath (reflections off of buildings), etc., and the reported success of a lab system like this begins to seem more like a flying car from the pages of "Popular Science" than something that will appear in the real world in the foreseeable future.

  3. 1Tbps vs 100MHz by Anonymous Coward · · Score: 0

    performance of 1Tbps (Terabit per second)

    delivered by using 100MHz of radio spectrum

    This sounds like it might cause some interference with surrounding channels.

    "You only need 100MHz of radio spectrum as long as you don't use the surrounding channels where we currently have some noise that we are trying to get rid of."

  4. Overlooking one small detail... by __aaclcg7560 · · Score: 2

    You can deliver more wireless bandwidth to users. Are you willing to pay big bucks to upgrade the backend equipment (i.e., routers and switches) for more bandwidth?

    *crickets*

    1. Re:Overlooking one small detail... by Archangel+Michael · · Score: 2

      Hell, certain "High Speed Internet" providers aren't even willing to apply a 10GB Fiber from one rack, to another, to help their users get content faster.

      http://qz.com/256586/the-insid...

      I remember seeing an interview with someone at Netflix, which basically said "Comcast has the bandwidth to carry all Netflix traffic, without issue. Netflix has the bandwidth to carry all the traffic requested by Comcast customers to Comcast, without issue. We have the capacity, they have the capacity, and if they need networking equipment so we can add a 10GB connection from our rack to their rack (at the COLO) we're willing to buy everything needed. They just won't do it"

      --
      Agent K: A *person* is smart. People are dumb, stupid, panicky animals, and you know it.
    2. Re:Overlooking one small detail... by allquixotic · · Score: 2

      Also, 100 MHz is *a lot* of spectrum to allocate to a single client, given the amount of spectrum that's currently available. They'd have to free up a lot of old spectrum that is used for obsolete stuff like 2G voice and 3G data, so that they could repurpose the spectrum for 5G. The only way they'd be able to pull this off, realistically, would be to increase tower density. 100 MHz is just too much to ask. Typical LTE bands have 1.4 MHz to 20 MHz allocated to a given LTE client; this increases that by a factor of 5 for the largest-width LTE deployments today, and by a significantly larger factor for LTE running on narrower widths.

      We can't just manufacture more bandwidth. Once the usable spectrum is allocated for something, we have to either wait until that technology goes obsolete and deallocate and repurpose it, or invent newer and better transceivers that can reliably transmit and receive over a previously unused range of frequencies (factoring in problems like building penetration, which gets harder at higher frequencies). Absent such advances in transceiver technology, we are stuck using the finite bandwidth ranges we have today -- at least for long distance cellular.

      So, while it's quite plausible to think they could allocate 100 MHz for this technology, maybe even as much as 500 MHz of spectrum for it, there would only be enough spectrum for a lot fewer clients at a time for each tower, compared to what we can do today.

      Problem is, there will be people who are perfectly happy with their 3G or 4G devices and resist upgrading, who want to remain customers under their current contract and continue to use the service already available. These folks are going to give carriers the motivation to retain their existing spectrum for the legacy protocols, inhibiting its repurposing for the next generation. It may be 50 years before the regulators officially announce, say, the 700 MHz LTE band to be free for a new auction.

      2020 seems to be very aggressive to me, mainly for policy reasons, not so much technical reasons.

    3. Re:Overlooking one small detail... by BronsCon · · Score: 2

      divide that 100Mhz channel into 1000 1ms time slots (or 10000 100 microsecond time slots and allow 1000 users 10 apiece, or keep dividing into smaller slices as the technology allows, to reduce latency) and provide 1gbps to 1000 users. Or 10000 1ms slots, to provide 100mbps to 10000 users.

      At the 1gbps per user level, that's a little less capacity (without overselling) than current towers, considerable more if oversold at current rates. At the 100mbps level, that's insanely better coverage in high-population-density areas, as each channel can handle 10000 simultaneous users without overselling, closer to 20k if oversold. At which point, interference becomes an issue and you have 20k users on the channel, each getting 10-20mbps; which is a huge improvement over the current situation during a conference, where the most anyone is lucky to get is a few kbps, due to radio interference, while the hard line running to the tower sits there mostly unused. It's not even a matter of the tower not having a large enough pipe to the network, the radios can't keep up with demand, so the pipe largely goes unused in these instances.

      --
      APK quotes people (including myself) without context and should not be trusted. Just thought you should know.
  5. Question! Shouldn't multiplexing be priority? by goruka · · Score: 3, Interesting

    I'm not an electrical engineer or anything close, but I live in a developing country and notice that the biggest problem here is not 3G or LTE speed (which just works fine everywhere) but that when a zone gets a little crowded, even if the signal strength is high, connectivity drops to E and stops working.

    Is this a problem that the specification does not allow more than a certain amount of frequencies per antenna and more are needed? As in, If it's so easy to saturate an antenna, shouldn't the extra frequencies, speed and bandwidth be used for allowing more connections instead first?

    1. Re:Question! Shouldn't multiplexing be priority? by mlts · · Score: 2

      Ideally, it should do both. One device would have an extremely large amount of bandwidth to play with if in range of the tower, but as more devices get handed off to the tower, there is less bandwidth per device, but all devices get some level of service until a threshold is reached where the tower cannot accept any more items, where even EDGE or GPRS speed cannot be maintained. This is especially important at sporting events or SXSW where there are tens to hundreds of thousands of people in one space. Assuming the tower has terabits of bandwidth available, it should at least provide 3G coverage, decent enough for people to pop selfies and upload them or tweet about how badly the band on stage sucks.

    2. Re:Question! Shouldn't multiplexing be priority? by tlhIngan · · Score: 2

      I'm not an electrical engineer or anything close, but I live in a developing country and notice that the biggest problem here is not 3G or LTE speed (which just works fine everywhere) but that when a zone gets a little crowded, even if the signal strength is high, connectivity drops to E and stops working.

        Is this a problem that the specification does not allow more than a certain amount of frequencies per antenna and more are needed? As in, If it's so easy to saturate an antenna, shouldn't the extra frequencies, speed and bandwidth be used for allowing more connections instead first?

      Most likely the control channel gets overloaded. It's the problem AT&T had when the iPhone came out - the iPhone was very aggressive with power management which resulted in it basically setting up and tearing down data connections on an almost per-tcp connection basis. This results in control channel overload, and other devices can't access it when they need it - perhaps when doing a handoff. The end result is the call drops because the phone can't establish communications with the next cell in time. And there is no relation to a cell's load level and its control channel load level - AT&T found that while the control channel was overloaded, they still had plenty of data and voice channels available - resulting in the worst performing carrier having the best data speeds.

      The control channel is used to set up and tear down links (voice channels, data channels), perform handoffs, handle SMS, etc. In crowded places, this can easily be overloaded - most providers set up additional micro-cells in densely populated areas to prevent this.

      Your phone is likewise seeing the same problem - it can't establish a 3G connection with the tower (overloaded control channel), so it falls back to 2G (which uses a different set of bands and thus has its own set of control channels) which are far less crowded where it can obtain service. Hence the "E" (stands for EDGE).

    3. Re:Question! Shouldn't multiplexing be priority? by kaiser423 · · Score: 2

      It already is multiplexed, via multiple access schemes. You typically see 3 antenna sets arrayed on a cell phone tower. Each of those typically operates at a different frequency set so that they don't interfere. Then in each of those coverage ares you're typically multiplexed via TDMA, or you're given time slices in which to communicate. There's only so fine that you can dice up time before either your calls get choppy, or not everyone in the cell can get synchronized enough to communicate effectively. Over the last couple of years, you've seen cell providers rolling out more and more stringent timing requirements to their sites, so that they can reduce the guard-time between slices and also ensure that all phones/devices are synced up better so that they make better use of their actual time slice.

      There's definitely more to it than that in a typical cell site (including other ways to add more users), but at some point you have to deal with physics. You have a certain amount of bandwidth at your frequency to use, and no matter how clever you get, there are thigns like noise, interferers, limitations on the sophistication of hardware you can put at cells or in phones, the laws of physics, etc. You hit hard limits pretty fast. One of the main reasons Verizon and some of the US networks went to CMDA was that at the time you could pack in more users per channel, because you weren't limited by timeslices, you were limited by SNR (more users effectively increased the noise floor since their codes wouldn't correlate), so you could get some pretty impressive numbers of users per cell, making deploying a network cheaper. Newer 4G and advanced 4G waveforms are kind of an interesting combination of an optimized waveform that's TDMA based, but has some similar features to other networks.

      This high speed is relevant, because you usually can use some of the techniques to divide up the bandwidth effectively to get more users per cell -- you can have smaller timeslices to transmit if the amount of data you can transmit in that timeslice is massive. The maximum amount of data passable over a link is kind of an industry standard metric for how much capacity a given channel can handle. It's easier to grok than channel capacity, etc

      TLDR: We're trying our damned best to multiplex as many users as possible into a cell site. The more that you can get in one site, the cheaper it is to operate and deploy networks, so tens of millions of dollars annually is spent making it better, and the strides that have been made are pretty darn impressive. But we still have work to do!

  6. OMG by TeknoHog · · Score: 1

    A summary that uses "bandwidth" in its correct, technical meaning? Heresy!

    --
    Escher was the first MC and Giger invented the HR department.
  7. How many movies is that? by Anonymous Coward · · Score: 0

    I don't understand this 1Tbps thing. Can someone tell me how fast it is in movies per second?

    1. Re:How many movies is that? by flappinbooger · · Score: 1

      I don't understand this 1Tbps thing. Can someone tell me how fast it is in movies per second?

      The proper unit on /. is library of congress per fortnight, but in 2015 it should be measured in netflix movies at 1080 resolution.

      --
      Flappinbooger isn't my real name
  8. Great! by Anonymous Coward · · Score: 0

    We'll be able to blow WAY past our data-caps so much faster!

  9. or $1.5-2 M in roaming fees in a second by Anonymous Coward · · Score: 2, Funny

    or $1.5-2 M in roaming fees in a second but let's say it takes up till 1 hour for you to get cut off you have a 1B+ data bill how are you going to pay that off?

    1. Re:or $1.5-2 M in roaming fees in a second by Anonymous Coward · · Score: 0

      Pre-paids? :>

  10. Only 100 meters by ITRambo · · Score: 2

    This will be a breakthrough when they can get their desired 5G speeds at 15 kilometers, or greater distances. Until then it's only PR.

    1. Re:Only 100 meters by Anonymous Coward · · Score: 0

      Current technology is useful. Why does it need to have a longer range than current gen to be useful?
      Or perhaps you just don't accept that there is a middle ground between breakthrough and PR?

    2. Re:Only 100 meters by jratcliffe · · Score: 1

      Um, why? The vast majority of cellsites deployed today cover areas with a radius of MUCH less than 15km...

    3. Re:Only 100 meters by fisted · · Score: 1

      I don't think I would want to be anywhere near that transmitter..

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    4. Re:Only 100 meters by phoenix_rizzen · · Score: 3, Informative

      Only 100 MHz, and using 100 MHz of spectrum. Most carriers in North America are lucky to have 10-20 MHz of contiguous spectrum, and maybe 40 MHz total usable spectrum in a specific area. Good luck finding 100 MHz of spectrum to use anywhere other than lab conditions.

      Would be nice if they worked on increasing the number of bits that can be transferred per MHz of spectrum, instead of increasing the amount of spectrum required to send the bits.

    5. Re:Only 100 meters by Archangel+Michael · · Score: 2

      I live in a city, and can go from full bars to no coverage in about 1/2 mile. (1KM). There are notorious dead zones in the middle of the city, because the city regulates cell towers, making cell service unusable in large swaths of town.

      Yeah, it is that bad.

      --
      Agent K: A *person* is smart. People are dumb, stupid, panicky animals, and you know it.
    6. Re:Only 100 meters by Anonymous Coward · · Score: 0

      Would be nice if they worked on increasing the number of bits that can be transferred per MHz of spectrum, instead of increasing the amount of spectrum required to send the bits.

      Easier said than done. As technology gets better, we can lower the noise and get better discrimination of symbols, but short range wideband communication is a better use of spectrum. Even better would be highly directional wideband systems.

      Diffuse, high power, narrow band transmissions are a waste of spectrum.

    7. Re:Only 100 meters by arvindsg · · Score: 1

      When comparing bandwidth its also important to compare what frequency we are talking about, after all there is exponentially more bandwidth available at higher frequencies(i.e. only 100MHz between 2.35 and 2.45GHz but 100Ghz between 2.35THz and 2.45THz

  11. How do you get 1Tbs in 100MHz of BW? by PeterM+from+Berkeley · · Score: 1

    Would someone please explain how you get 1Tbps of data through just 100MHz of bandwidth?

    I just found a (not very credible) reference on the Internet that claimed that the amount of data you could transfer would be limited by your available spectrum frequency bandwidth. I.e., if you'd have the same data transfer capability if you could use 0 to 100MHz as if you could use
    1GHz to 1.1GHz.

    So how do you get more than 100Mbit through 100MHz of bandwidth?

    1. Re:How do you get 1Tbs in 100MHz of BW? by Anonymous Coward · · Score: 1

      Using multiple beams formed by an array of antennas. No single user gets all that data bandwidth, but the total data bandwidth can be directed in multiple directions, using spatial structure to increase the total data rate with the same radio bandwidth.

    2. Re:How do you get 1Tbs in 100MHz of BW? by jratcliffe · · Score: 1

      It would be a huge leap, LTE Advanced (i.e. 4G) could, in theory, get to around 15 bits/Hz (currently LTE's around 4), but this is more like 10,000 bits/Hz.

    3. Re:How do you get 1Tbs in 100MHz of BW? by davidwr · · Score: 1

      Using multiple beams formed by an array of antennas. No single user gets all that data bandwidth, but the total data bandwidth can be directed in multiple directions, using spatial structure to increase the total data rate with the same radio bandwidth.

      This. Very much this.

      Even so, a 1:10000 ratio of bandwidth to bit-rate is noteworthy.

      I don't see this being practical except in either 1-box-to-many-boxes "point-to-points" situations or in situations where reflection and other characteristics are either very predictable or ascertainable in real-time. The former is uncommon and the latter is hard.

      A case of 1-to-many might be in a home or office where a single node is connecting to many fixed-point antennas in an "Internet of things" environment or even to fixed location computers (look ma, no more running wires through the ceiling!).

      --
      Knowledge is how to play a game, intelligence is how to win, wisdom is knowing what game to play.
    4. Re:How do you get 1Tbs in 100MHz of BW? by Anonymous Coward · · Score: 1

      There's no 1:1 relationship between Hz of bandwidth and the bits per second you squeeze through. The available signal to noise ratio is the other important factor. The good old analog modems managed 28.8 kbps in a 4kHz bandwidth channel. Check http://en.wikipedia.org/wiki/Quadrature_amplitude_modulation or http://en.wikipedia.org/wiki/Phase-shift_keying

    5. Re:How do you get 1Tbs in 100MHz of BW? by Anonymous Coward · · Score: 0

      That is not the way it works.
      If you look at the spectrum usage of a PSK or QAM signal you will see that the transitions creates signal outside of the base frequency. It is very easy to see in the PSK case since you by switching phase can create a signal at a much lower frequency or higher frequency.
      The point of using different modulations is to get a better signal to noise ratio. Not to cram more data into a frequency range than what is physically possible.

    6. Re:How do you get 1Tbs in 100MHz of BW? by Dr+J.+keeps+the+nerd · · Score: 1

      For those of you looking to try it at home, there is at least one Software Defined Radio platform that will drive the ~1000 spatial streams you would need for this:

      http://nutaq.com/en/products/titanmimo/titanmimo-6

    7. Re: How do you get 1Tbs in 100MHz of BW? by Anonymous Coward · · Score: 1

      You can get as much data as you want through any bandwidth (theoretically anyway). What kills the ability to transfer data is when noise in the channel makes it impossible to determine if you are seeing data or noise. The Shannon theorem covers this. But this only specifies a limit to the amount of data you can transfer given a certain SNR.

      Nothing says you can't find ways to reduce the noise (better amplifers, antenna etc) or simply just increase the signal power. Doing this in a practical way is the challenge and what these researches are attempting to do.

    8. Re:How do you get 1Tbs in 100MHz of BW? by chadkennedyonline · · Score: 1

      Take a look here: http://en.wikipedia.org/wiki/S... 100MHz of bandwidth only equals 100MBps throughput if Signal power = Noise power. Working backwards implies the SNR from the experiment is 30000. I'm not sure if that is a reasonable number or not, but sound high to me. My work: 10 * math.log10(2**(1e12/1e8) - 1)

    9. Re:How do you get 1Tbs in 100MHz of BW? by Anonymous Coward · · Score: 1

      base frequency and bandwidth are two different things. Any modulation method genrates signals "outside the base frequency." Even just turning the carrier at a single, precise frequency on and off generates a signal with a non-zero bandwidth.

    10. Re:How do you get 1Tbs in 100MHz of BW? by Dr+J.+keeps+the+nerd · · Score: 1

      Shannon's theorem is true for a single channel. Eventually, cramming in more bits into one channel becomes power-prohibitive, because one must double power for each new bit added in. The benefits from adding power diminish even further when a system is widely deployed, as power from one system shows up as noise in the next, and SNR in all systems hits an interference limit.

      To get around these limits, two related techniques are used
      1) adding more antennas, to create more channels which are separated in space
      2) coordination techniques that reduce interference from one spatial channel to another

      If 2) is done well, then 1) can provide the kind of linear benefits you'd hope for - each new channel contributes its share to the sum data-rate. As you might imagine, building very parallel radio systems and coordinating what's sent over them presents its share of challenges.

    11. Re:How do you get 1Tbs in 100MHz of BW? by kaiser423 · · Score: 2

      You make multiple measurements, and you get more fine grained measurements. Originally you had on/off keying (AM modulation). On = 1, Off = 0. You had FM modulation, where +freq = 1, -freq = 0. It's easy to see how to make either of those better -- for on/off keying, a simple amplifude modulation. Full power = 11, 2/3rd power = 10, 1/3 power = 01, off = 00. Boom, double the bit rate in the same amount of bandwidth (technically, potentially a little bit less if you do things right). You can see how you can infinitely divide that -- you can track 4, 8, 12, 16 power levels, etc. You can do the same thing with the phase of the carrier -- change phase by half phase intervals, or quarter, etc. Then you can combine the two and end up with a constellation of points, which is basically QAM. You see QAM-16 (16 discrete phase/amplitude points), QAM-64, QAM-128, etc.

      Now, if you've been thinking about implementation details, you realize that the fundamental question is: "how do I know that I'm at half power instead of full, or my phase has changed?". Well, there's basically a synchronization period -- you listen to the stream for long enough to kind of know where you are at. Some streams also send synchronization patterns periodically. The next issue then is "what happens when my signal fades, or my signal bounces and the phase gets screwy". The answer then is in algorithms and multi-hypothesis guesses as to how the channel medium is acting. Lots of math there, but no matter how good you get more highly advanced tighter packed schemes are going to be more vulnerable to things like signal fades, etc and then also take more time to get back up to speed because you need more symbols flying by you to sync up to where you are at. But you can push them at a higher rate, so you gain some of that back. You end up wit ha constellation that you synchronize to, and then to make it more complex, Fourier tells us that if the bigger phase/amplitude change you have per bit period, the more bandwidth you occupy. So, actually, sub-dividing the phase/amplitude helps you generally occupy less bandwith, but you can also get tricky where the constellation is adaptive in such a way that you minimize amplitude/phase changes for each bit set transmitted, making you occupy even less bandwidth. But that's one more thing for the receiver/transmitter to keep in sync....

      As you can see, this gets incredibly complicated quickly. It's a very math heavy field, with lots of very neat, clever tricks to make it all work seamlessly. These guys just figured out how to maintain coherency, etc at higher frequencies, which is fairly notable, but this march is expected to carry on as we get faster processors, higher performance amplitude/phase modulators, and low noise devices we can keep packing those bits tighter and having more points on the constellation.

    12. Re:How do you get 1Tbs in 100MHz of BW? by silas_moeckel · · Score: 1

      MIMO, you can have more than one set of signals without completely interfering.

      --
      No sir I dont like it.
  12. Meanwhile... by Anonymous Coward · · Score: 1

    Wired 10Gbit ethernet is still not affordable for home use.

  13. Mod Parent Up by jddj · · Score: 1

    I think this busts the physics, unless I misunderstand completely. Paging Dr. Shannon...

    1. Re:Mod Parent Up by serviscope_minor · · Score: 4, Informative

      I think this busts the physics, unless I misunderstand completely. Paging Dr. Shannon...

      Nope.

      Think about baseband for a moment.

      Let's say you hae a bandwidth of 100MHz.

      You can basically change from 0v to 1v 100e6 times per second, giving 100Mbit/s.

      But you can also introduce more symbols. If you have 10 voltage levels between 0 and 1 V you get 1Gbit /s.

      What limits the number of symbols is noise. The datarate is symbol rate * bits per symbol. In the absence of noise, you can transmit an infinite amount of data in a 1Hz channel.

      For non baseband signals, they generally use QAM to get symbols spanning the whole phase space around the centre frequency.

      --
      SJW n. One who posts facts.
    2. Re:Mod Parent Up by freeze128 · · Score: 1

      Also, the frequency used in the experiment turns small animals inside-out.

    3. Re:Mod Parent Up by ledow · · Score: 2

      Cat5 cables is only aimed at 100MHz signals, but you can put Gigabit Ethernet over it.

      The number of bits sent does not have to be less than the frequency of the carrier (or even half that).

      Phase, amplitude, frequency-modulation, plus others, all combined allow you to get a lot more out of the signal than merely the carrier frequency rate.

      Otherwise your old 56Kb/s modem of old would never have got to that speed, your DSL modems wouldn't come close, your wifi would be nothing more than a radio modem, etc.

      Hasn't been true for decades, and with multiple antenna etc. tricks you can do even more.

    4. Re: Mod Parent Up by jddj · · Score: 0

      Well, if I understand GB Ethernet (with which I've wired my home, to ease passing MPEG-2 OTA TV streams around), it moves from one twisted pair to four, at the 100Mbit clock rate, and so approximates 1Gbps, though doesn't quite equal it.

      So not a like-for-like comparison. While the summary doesn't say much, the other provided explanation (multiple spatial paths) seems something like GB EN, in that there are multiple channels in which the information is transmitted.

      Hard for me to see how you cram a Terabit down a 100MHz single channel, but perhaps that's not what's being attempted.

    5. Re: Mod Parent Up by ledow · · Score: 2

      There are four twisted pairs. Assume they are 100MHz each. That's only 400MHz (800 if you think the other one of a pair does anything (*)). Yet you push 1000Mbits a second over it (and, yes, that's the actual speed) .

      How? PAM, QAM, and a bunch of other tricks - because you think you need an entire cycle/wavelength in order to encode a single bit of information, which just isn't true.

      (*) it doesn't - the other half of the pair allows you to subtract interference received along the same route by an equal length cable. Much like MIMO antenna differencing.

  14. That depends by davidwr · · Score: 1

    How many 360KB floppies does it take to hold each movie in your collection?

    Also, "per second" may introduce rounding errors. "Per fortnight" is the traditional unit of time for things as large as a feature film (or rather, for truckloads/planeloades of the same).

    --
    Knowledge is how to play a game, intelligence is how to win, wisdom is knowing what game to play.
  15. So Awesome by CimmerianX · · Score: 1

    With this we can blow through our 2GB wifi data limits in a fraction of the time.

  16. Not even close by fisted · · Score: 2

    1 Tbps = 1e12 bit/sec
    2 GB = 8*2*2^30 = 2^34 bit
    2^34/1e12 ~= 0.017 sec

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    1. Re:Not even close by fisted · · Score: 1

      PS: even simpler, it should be fairly obvious that 2 GB in roughly 1 second gives a rate of ... well, roughly 2 GB/second, not 1 Tb/second..

      --
      CLI paste? paste.pr0.tips!
    2. Re:Not even close by Shakrai · · Score: 3, Insightful

      Sure, if you're using a burst transmission that doesn't wait for acknowledgments or the TCP window size to be set. My calculation totally took those variables into consideration. It's not as though I misplaced minutes for seconds or anything that stupid, it's not like that at all. :)

      --
      I want peace on earth and goodwill toward man.
      We are the United States Government! We don't do that sort of thing.
  17. Are they "Big Data" Scientists ? by Anonymous Coward · · Score: 0

    "UK Scientists Claim 1Tbps" - that is a lot of data, are they "Big Data" scientists ?

  18. Team of Scientists? by Anonymous Coward · · Score: 0

    I would call this a group of engineers, not scientists. These folks are doing engineering, plain and simple. The referenced article says a group of researchers, not explicitly scientists. Just saying.... ;-)

    1. Re:Team of Scientists? by Dr+J.+keeps+the+nerd · · Score: 1

      If I'm reading the comments section correctly, they might as well be magicians.

  19. Team of Scientists? by Anonymous Coward · · Score: 0

    Well at least they are not geologists

  20. Nice! by nospam007 · · Score: 1

    We could leech all the movies of a year in 1080, all the series, all the ebooks in under a minute.
    Way to go.

  21. It's a crime by Anonymous Coward · · Score: 0

    4g and LTE are both capable of well over 1Gbps but somehow we are paying hand over fist for low tier DSL speeds. All of the mobile provider execs should be put on trial for fraud!!!!!

  22. The irony of living in the US with the crap corps by lamer01 · · Score: 1

    Watching the rest of world move past is not a fun thing to do.

  23. RIDDICULOUS!! by Anonymous Coward · · Score: 0

    RIDICULOUS!!!!

    This so called 'professor' allegedly built a system that can operate at 63000 dB SNR.
    What a load of bulls**t!!

    By Shannon's capacity theorem:
    C = B*log2(1+SNR)
    with C=1e12 (1Tbps) B=100e6 (100MHz of spectrum)

    you get:
      SNR = 2e3000 = 69000 dB (!!!)

    Listen, wireline/optical comm links, which have considerably better SNR's than radio-links, achieve typically 1, 2, 4 bits/hz of spectrum. CATV achieve maybe 10 even 12 bits/hz.
    BUT NOT 10000 bits/hz, RIDICULOUS!!

    No wonder he doesn't want to give any details regarding his setup..

  24. Oh good ... by __aapsaf2058 · · Score: 1

    ... now I'll be able to burn through my allotted bandwidth in 1 second.

    That's just excellent news.

  25. Why bother with tiny data limits by bobjr94 · · Score: 1

    Companies like verizon think bandwidth is scarce and charge crazy overage fees if you even think of going over. I can't even math that well, but seems with 100% saturation, you would use up a 4gb data plan, use another 121gb in overages in 1 second. At their current rate of 15$ per gb, that first 1 second would costs you little over $1800.

    1. Re:Why bother with tiny data limits by arvindsg · · Score: 1

      Its rather that companies like Verizon think money is scarce, need more.

  26. It's not about your data cap... by Ranbot · · Score: 1

    That's a funny post, but it misses the real point, which is speeds like that over mobile networks can compete with traditional land-based ISP speeds. These are some of the first hints at a massive shift in how consumers will access the internet and ISPs will operate in the not-so-distant future. Last month Verizon quietly announced that they weren't going to lay any more fiber optic cable and are selling some fiber networks to third parties because their wireless networks were much more profitable, which is probably true, but it's only part of the story. If you consider various reports like this about the potential for 5G you can read between the lines of Verizon's statement; they know the future of home internet is very likely going to be wireless and want to be ready.
    (Reference: http://tech.slashdot.org/story... )