16 ms·
5G and Shannon’s Law
- ihsw 6y agoComputer-assisted driving and self-driving cars are an obvious application of low-latency high-speed cellular networking, what else is there? Drones?
- m000z0rz 6y agoWarning, this page does the annoying chatbot thing, but with the addition of sound notifications.
- ehsankia 6y agoI thought the one lesson we all learned from Clippy is that this kind of interruption is more annoying than useful, I guess the new generation of developers have never experienced Clippy? Also why would I need help when reading a blog post??
- deleted 6y ago[deleted]
- anonymousab 6y ago>I thought the one lesson we all learned from Clippy is that this kind of interruption is more annoying than useful It's not about usefulness, not really. It's about engagement and retention - much like newsletter spam and annoying please-subscribe popups, The Metrics always apparently show that they work amazingly compared to a clean page.
- metaphor 6y agoOh yes, hand-waving "The Metrics". What do they say about how often and the speed in which reader view was enabled?
- phendrenad2 6y agoI especially love when these things pop up on careers pages. Just demonstrate to me how lazy your programmers are and apply the chatbot to all pages, why don't you?
- nine_k 6y agoLiving with uMatrix and having sometimes click it and enable more page scripts is still less annoying that things like this.
- sinak 6y agoAuthor here. Sorry about that. I just turned it off.
- twoodfin 6y agoThe scaling of wireless bandwidth is one of the under appreciated technological miracles of the 21st Century. I wonder: Would even the most ambitious of telecommunications researchers in 1990 have thought it likely that in 2020 we’d be rolling out gigabit wireless speeds to handheld devices over nation-spanning networks? The scaling of Moore’s Law was clear by then, and certainly fiber optics represented a practical path to near-unlimited wired bandwidth. What were the radio folks thinking at the time?
- vvanders 6y agoProbably? There is a fair bit of overlap between cable/fiber and radio in that both are mostly QAM, multichannel based. Radio tends to have a worse SNR and a couple other tricky problems tacked on top.
- aoki 6y agoAmbitious wireless folks were already pitching MIMO mobile networks to investors. For example, ArrayComm was started in 1992.
- tinus_hn 6y agoSo the patents expired in 2011!
- AnthonyMouse 6y agoI still don't really get the point of 5G. It requires so many towers that you're basically building a wired network, but then it requires billions of dollars worth of wireless spectrum in order to get from what amounts to the street in front of your house to inside, even though there are already phone lines and coax going there that could be used. Even for wireless devices, that would get you close enough to use unlicensed spectrum (WiFi) and save billions of dollars worth of licensed spectrum. The main benefit of cellular is when you're away from WiFi. But unless you're constantly traveling to places without WiFi, you get that from a $20/month plan and the existing cellular network.
- 6y ago
- 5gisbad 6y agodoes anyone question the health effects here
- sumanthvepa 6y agoOne thing to note is that the frequency bands specified only apply to US 5G. Huawei's 5G spectrum uses a much lower frequencies: Around 3.8GHz. This falls in the mid-range spectrum, which makes it cheaper to deploy, because the waves travel further and you need fewer towers. That is the attraction of Huawei, for most countries (outside of the US). Ref: https://www.huawei.com/en/about-huawei/public-policy/5g-spectrum#:~:text=Sub%2D8GHz%20frequency%20band%20for,primary%20bands%20in%20specific%20countries https://www.huawei.com/en/about-huawei/public-policy/5g-spec.... EDIT: Fixed typos.
- o-__-o 6y agoAlso interferes with a lot of hospital devices that operate in that freq range. It’s a fight I am casually observing from the sidelines with popcorn.
- magicsmoke 6y agoIsn't the ISM bands at 2.4 and 5.8 GHz? That shouldn't be interfered by 3.8 GHz 5G signals. Is it because of out-of-band intermodulation from 5G signals or because there are parts of the 3.8 GHz spectrum used by medical devices not for wireless networking but for sensing/measurements?
- jessaustin 6y agoWifi has been around a long time now. Why can't the hospital devices just use that like everyone else? (Oh except wireless microphones in churches, which are also some special snowflake exceptions for some reason...)
- chongli 6y agoBecause everything interferes with WiFi. It’s junk spectrum. You don’t want critical, lifesaving devices operating on the same spectrum as the microwave in the break room.
- jessaustin 6y ago
- cinquemb 6y ago> there are theoretical limits for each medium. I would rather say that there will always be limits of our understanding and building equipment for usage in various mediums, even in a vacuum, we're still only probing our theoretical knowledge of null boundary interactions between photons[0]. > For example, a standard cellphone can fit an array of 72 antennas operating on the 39 GHz mmWave band. A similar 72 antenna array in the 700 MHz low-band frequency would be larger than a typical home door. And what would it cost? In an environment where cellphone sales have been declining for at least 5 years now at least on the high end (all the games Apple has been playing with sales reporting…), which end users will be willing to bear the cost of the device now? [0] https://www.youtube.com/watch?v=bH7OGkEZX7I https://www.youtube.com/watch?v=bH7OGkEZX7I
- owenversteeg 6y agoFirst of all, this is an excellent explanation of 5G that anyone moderately technical can understand. Great article. That said, do the numbers from the article concern anyone else at all? I'm generally all for progress, but more than 1 million devices per km2? And massive MIMO antenna arrays spraying EM waves in every part of the spectrum from 600 MHz to 50 GHz? More than a million devices per km2 ~= 3 million devices per square mile. Am I the only one that thinks that's a bit crazy? I don't want everything from my toaster to my door to my water bottle to be transmitting massive amounts of information to who knows where all the time. More concerning: the antennas. Current regular MIMO 4G towers are 2x2 or 4x4. Already, there are 5G towers installed today that are 128x128. These are planned to be spaced -extremely- densely in cities, and very close to people (on every floor of offices, on lampposts, etc.) This is a necessity due to the spectrum used. And not only that, but they're using new spectrum that hasn't been used before - instead of the MHz to low GHz range we all know and trust, 5G towers will be up to near 50 GHz (!). Especially the fact that millimeter wave/extremely high frequency is normally blocked by everything from drywall to glass, but now we're intentionally aiming massive amounts of EHF waves with hundreds of antennas in a small space. Call me a luddite, but I'm more and more thinking that we need a high quality longitudinal study about any effects of this kind of stuff before we go from 2x2/4x4 at well known frequencies to putting 128x128 EHF antenna arrays every hundred feet.
- oakwhiz 6y agoI'd be more concerned with the fact that the increased quantity and precision of the antennas allows collection of extremely fine-grained location information.
- mNovak 6y agoThis is an interesting thought. It wouldn't be more precise than the GPS tracker already in your pocket, but it does open up more info to people other than Google. Also as a note, regular MIMO (not "massive") wouldn't provide location information as the scattering channel is generally considered random.
- ip26 6y ago
- barryaustin 6y agoExcellent article - still I can't resist a rather large quibble. The commonly stated assertion that spectrum is a limited resource is not quite accurate. Spectrum is technically defined as a range of frequencies. That's all. In business parlance spectrum is also attached to large areas of land - this spatial dimension is more important than most people realize. Radio signals themselves exist in space and time, not just in a range of frequencies. More radio signals - and data bandwidth - can be packed into a given space by shrinking the volume a given signal "occupies". We can do this by reducing signal power and increasing cell density, in addition to other techniques described in the article. More cells, smaller cells. This is a big part of how 5G expands cell network capacity. But the telecoms have downplayed the effect of this relative to the the claim that spectrum is limited. The mobile carriers have financial incentives to do this. These incentives are lower costs and monopoly control. Fewer bigger cells at higher power are cheaper than many smaller cells at lower power. The monopoly part is exclusive use of spectrum on a given piece of land. The problem is, the legal attachment of spectrum works with very large areas of land (where km^2 is a smallish unit) and large periods of time (years), relative to radio signals. Both attachments are grossly inefficient. By shrinking cell size (power) and increasing cell density, several orders of magnitude more network bandwidth is possible, plenty even to share (modulo cost of physical infrastructure). Spectrum scarcity is a myth. The current legal regime enriches monopolists and is otherwise a tremendous waste of potential. We pay higher prices for unnecessarily limited bandwidth.
- mNovak 6y agoSpectrum scarcity is also a function of our wasteful utilization. What you describe (small cells) is one version of what we call spatial multiplexing. Basically, reuse spectrum in physically separate areas. But you can also do this in a way that doesn't sacrifice the centralized, large cell architecture. Namely via beamforming. You don't have to share spectrum if you're not dumping power in all directions. Already cell towers are split into three sectors; you could continue to increase sectors, or dynamically point beams at individual users. Being suitably isolated from one another, each beam allows spectrum reuse. It's not free obviously, it requires more expensive base station antennas, but I think a direction we'll be heading in.
- fyfy18 6y agoWould anyone like to speculate on what new tech we will see that will take advantage of this? I can already stream (to my device) a 4K 60fps video while in a park, and at home I have gigabit fiber (up and down) which is barely ever used to it's full potential. What cool stuff will I be able to do in 10 years time when I have 10Gbps upload while sitting in a park?
- cinquemb 6y agoOne isn't really supposed to ask these questions, and just assume: - that every cellphone user in the world is going to just run out tomorrow and buy a phone that's $200-300 more expensive to replace the phones they have now, have been replacing less and less of in the past half a decade, that they barely utilize to its fullest if the network were just prevalent everywhere today - that some measurable fraction of the towers spaced every 150ft will not be vandalized, broken and sold for scrap in many places in the world and have to be replaced in order to have the throughput as advertised, that the companies will be just excited to replace, whose total cost will be less or the same as current infrastructure costs - that despite the junk rating of many of the biggest teleco corps, they are well capitalized with pay for such a network from the ever increasing profits they reap from current consumers and wont have to rely on more junk financing and will take great care of the infrastructure just like all the great care they have put into existing infrastructure. Nothing in the future could ever threaten their solvency I wish them all the best!
- Nursie 6y agoYou'll be able to ditch the home fibre connection. You'll have lower energy use modes available for battery powered IoT devices. You'll be able to be in a very dense crowd and have your services still work. It is also lower latency that 4G, so things like gaming over your 5G connection become more possible. These may not matter to you, but they are use-cases that 5G allows.
- ghaff 6y agoIt's not clear to me that it makes sense to replace wired with wireless when density is such that fibre can be economically laid to a location. 5G has a lot of possibilities both for improved mobile data and for last mile where it either doesn't exist or is some old 1Mbit ADSL line. But I'm not convinced it will generally make sense to ditch good wired broadband just because 5G is available. Even if you technically could, I expect the economics won't work out, e.g. throttling/caps/overage charges, for people trying to do a lot of data-heavy things like video streaming if they have an alternative.
- lmilcin 6y agoActually, low range of high frequency signal is beneficial. The reason is, that even at relatively large transmission power the signal dissipates quite quickly meaning you can have stations service relatively small area. This means the spectrum is shared by less users, the uplink is shared by less users, you can serve higher concentration of people.
- ksec 6y agoJust a note. Massive MIMO is not a 5G only thing. 3GPP Rel 13 on 4G already had it for FDD-LTE. And for TD-LTE it was supported from Released 8 or 10 if I remember correctly. Massive MIMO in 5G only meant NR was designed with it in mind. Although mostly in the sense of TDD still, FDD Massive MIMO still has some on going work to do. But yes, in many case 5G is more like 4.99G. It is pretty much a evolutionary step from 4G Rather than a big leap from 3G to 4G. And we should expect capacity to increase from 5x to 10x.
- baybal2 6y agoMultipath MIMO can effectively beat both Shannon, and Nyquist through utilising multiple spatial channels.
- jessaustin 6y agoNo mention of unlicensed bands? After the demonstrated superior utilization of those tiny portions of this range allocated for ISM? My goodness, it's almost as if FCC works only to perpetuate outdated "giant telco" models to the detriment of all consumers! Out here in the country we'll operate our own "small cells" without permission from ATTVZN and without paying FCC a cent. If anyone notices there will be "investigations" but mostly no one will notice because physics. Eventually industrial users of this tech will realize "hey we don't need those telco goofballs either!" and their lobbyists will muscle through some exceptions. Eventually everyone whose house has sheetrock walls will be so excepted.
- ac29 6y agoThis article wasn't about unlicensed/ISM radio, though there have certainly been advances there as well. I'm genuinely curious about which parts of the ISM range you see with "superior" utilization compared to cellular networks - I work with those type of radios for a living.
- jessaustin 6y agoFor most of the spectrum, the devices and services that consumers may purchase are limited to those available from giant hierarchical oligopolies. In the ISM bands, we have a bunch of different technologies, but most importantly Wifi. There are much less stringent barriers to anyone using or selling devices and services that use Wifi. And it all works! Those who live in dense urban areas sometimes scoff at Wifi, but what they're seeing is the tiny segments of spectrum allocated to unlicensed use, not inherent problems with open spectrum. The excuse offered in the past for spectrum oligopolies was "oh it's physics" because the very simplest radio technology we could imagine in the 1930s does suffer from interference at lower frequencies. Of course we've had more advanced radio tech for a long time, but ignore that... at the frequencies under discussion for 5G, interference over any but the shortest range is no longer a threat. That means that most of the claimed justification for telecom monopolies (and perhaps the agency created to enforce those monopolies) goes away. It's sad that TFA is still focused on "carriers".
- 6y ago
- T3RMINATED 6y agoWhat about the high rates in brain cancer?
- k__ 6y ago"5G towers won’t be “towers” – instead, they’ll be “small cells,” mini-cell sites mounted to light poles that cover just a small area" I had the hope, 5G would finally solve the coverage problems in rural areas. sounds like it's just a vanity project after all...
- badrabbit 6y agohttps://www.gaia.com/article/5g-health-risks-the-war-between-technology-and-human-beings https://www.gaia.com/article/5g-health-risks-the-war-between... We should not listen to scientists about 5g health concerns? 5g highband is basically an always on radio that can pinpoint specific users. Like,you would be tracked as you move room to room and interact with people. Why is everyone ok with this? Especially when hardware killswitches are not the norm or legally required.
- donclark 6y agoHow does Starlink fit into this scenario?
- AtomicOrbital 6y agoif anything 5G will put extreme pressure on more efficient computational paradigms to replace our half century old silicon approach ... biology evolved the human brain to run on 40 watts of power ... the massive additional carbon footprint of 5G will accelerate our escape from silicon