The scaling of wireless bandwidth is one of the under appreciated technological miracles of the 21st Century.<p>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?<p>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?
First of all, this is an excellent explanation of 5G that anyone moderately technical can understand. Great article.<p>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?<p>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.<p>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.<p>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.
One 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).<p>Ref: <a href="https://www.huawei.com/en/about-huawei/public-policy/5g-spectrum#:~:text=Sub%2D8GHz%20frequency%20band%20for,primary%20bands%20in%20specific%20countries" rel="nofollow">https://www.huawei.com/en/about-huawei/public-policy/5g-spec...</a>.<p>EDIT: Fixed typos.
Excellent article - still I can't resist a rather large quibble.<p>The commonly stated assertion that spectrum is a limited resource is not quite accurate.<p>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.<p>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".<p>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.<p>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.<p>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.<p>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).<p>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.
Would 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?
Actually, 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.<p>This means the spectrum is shared by less users, the uplink is shared by less users, you can serve higher concentration of people.
No 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!<p>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.
<i>"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><p>I had the hope, 5G would finally solve the coverage problems in rural areas. sounds like it's just a vanity project after all...
<a href="https://www.gaia.com/article/5g-health-risks-the-war-between-technology-and-human-beings" rel="nofollow">https://www.gaia.com/article/5g-health-risks-the-war-between...</a><p>We should not listen to scientists about 5g health concerns?<p>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.
Just a note.<p>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.<p>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.
if 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
> there are theoretical limits for each medium.<p>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].<p>> 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.<p>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?<p>[0] <a href="https://www.youtube.com/watch?v=bH7OGkEZX7I" rel="nofollow">https://www.youtube.com/watch?v=bH7OGkEZX7I</a>