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London Needs 70,000 Cells For 4G
judgecorp writes "How many cells does it take to cover a city? In London's case, it will take 70,000 cells by 2015 for the next-generation LTE network needed for 4G mobile broadband, according to a calculation from PicoChip. A shame that's too late for 2012, when Mayor Boris Johnson warns that mobile data demands during the Olympics may overload the current 3G network"
A shame that 70000 cells are not rolled out by 2012?
I would call that wise money management, given how many 4G terminals there will be available (i.e. few) sompared to the number of 3G devices.
Better to build WiFi / 3G picocells for the Olympic' hotspots.
Why does anyone want traffic clogging up their pipe when the problem is the big pipe.
Scattering transmission locallty to other routers only spreads the problem out..
FTA: "Femtocell maker Picochip says London needs large numbers of micro cell towers by 2015" and "Dr Pulley’s report also stated that there needs to be in excess of ten million small cells worldwide by end of 2015". Now why would a maker of small cells say that?
The gear exists to create a femto-cell in your home where you reroute your phone over your ADSL/cable. I often wondered, why don't they allow strangers to jump on the unused bandwith? Say I have a 10 MBit subscription, but my modem can handle 20. Why doesn't the telco open the remaining 10 for anybody comming by? Specially in downtown Londo where a lot of buildings must have direct fiber... Anybody can answer this?
10 ?"Hello World" life was simple then
Latency, many other reasons..
Not if the P2P back-end existed only in vehicular or fixed installations, instead of on one's hip.
Kid-proof tablet..
First it was microcells, then nanocells, now femtocells. What's next, QuantumCells? PlanckCells? Eesshh.
Vote monkeys into Congress. They are cheaper and more trustworthy.
I guess you can solve local connectivity with p2p, but I don't think it gives you more bandwidth. Transmitters are still sharing a resource.
Cell phone communications require synchronous communications and P2P is mostly asynchronous in nature.
Take for instance the standard smartphone. It has no fan, no swap memory, and its limited battery life is its biggest constraint. Run a P2P app on it and just see what happens. It will run super hot in your pocket. And its battery could get drained long before you ever get a chance to make your first phone call of the day.
They're centiprefixes.
The calculation is probably correct assuming the whole city needs to be covered by small (femto/pico) cells, which is of course something that small cell vendor would like very much. In reality, many areas with relatively low population/phone density can probably be covered by a macro network and high density areas - shopping malls, apartment buildings, university campuses will need to be covered by femto or pico cells.
In reality, many areas with relatively low population/phone density can probably be covered by a macro network and high density areas - shopping malls, apartment buildings, university campuses will need to be covered by femto or pico cells.
Sure - there'll always be a mix of small and large cells. But most of London is "high density areas". And it can be very difficult/expensive to find good sites to put full sized cell towers. If you can put many smaller cells inside buildings etc, just like WiFi stations, then it'll probably save the carriers a lot of money.
The current deployment of BTSs for cell coverage needs a different approach.
Especially because in a crowded city like London, most of the BTSs would be femtocells or picocells.
If only a BTS would cost, say UKP 1,000 each, that coverage would cost UKP 70M, without counting the yearly maintenance costs.
For each non-virtual operator.
Unless we also start pushing for telecom infrastructure sharing.
Sent as ripples into the electromagnetic field. No single photon has been harmed in the process.
Logical filters, maybe, but certainly not physical ones. Otherwise, AT&T's GSM network (and a fairly big chunk of T-Mobile/US's network) couldn't exist. In America, using the same band for uplink and downlink is the norm. I believe this is also the case in Australia and a few other places where 850MHz and 1900MHz (without 2150MHz) are used for UMTS.
A shame that's too late for 2012, when Mayor Boris Johnson warns that mobile data demands during the Olympics may overload the current 3G network.
Gee, ya think?
Although, to be quite honest, there's no such thing as enough preparation/bandwidth/security/anything for an Olympics.
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What do you mean by P2P?
Point to point? That's already how cell phone networks connect - cell phone to cell site.
Peer to peer? That only works if the person you happen to call is very local, cell phones don't have the power to go far.
I think you probably meant to ask why not create a mesh network, and that brings up issues of security and power consumption, without really helping the bandwidth. (Power consumption, because it would require more phones to be actively operating, rather than being idle, to work).
"National Security is the chief cause of national insecurity." - Celine's First Law
The powers that be don't want us to have mesh networking devices because that is the technology that will let us route around them. Not the first devices, of course, but if you have a bunch of mesh networking devices running around carrying IP traffic on some other network the logical thing to do is to eliminate the other layer and run an IP network. This is the same reason for the unnecessary resistance to IPv6 (as opposed to the necessary resistance from the incompetent.) The last thing these corporations want is for us to all end up on some kind of network where we don't need them.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
The whole POINT of a cellphone network is to get the maximum data moved while using only a small ammount of RF bandwidth. They do this by
1: moving the data a short distance using radio and moving it most of the way over wired networks. As the user density increases networks add more base stations so that the signal travels less distance by radio and the power and reuse distances are reduced.
2: carefully planning the use of frequency space first by allocating it to towers and then having the towers allocate it to users.
multi hop routing (what I presume you meant by P2P) with end devices acting as repeaters is a nice idea if you are trying to maximise coverage and have low capacity needs, it's a crappy idea if you are trying to provide maximum capacity.
note: i'm known as plugwash most places but i screwd up registering that here somehow in the past and now can't register
London calling to the faraway towns
Now there's too much traffic and network goes down
London calling to old CGI Perl,
Come texting the shortcodes, all you boys and girls
London calling, now don't look at us
But that silly iPhone mania has bitten the dust
London calling, see we ain't got no bling
'Cept for the ringtone that sounds like swing.
The tech age is coming, the screen is zooming in
Engines stop running and the bandwidth growing thin
A critical error, but I have no fear
London is lagging and I've spilled all my beer.
I am officially gone from
LOfuckingL
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Uplink and downlink are at different frequencies in the US on all the equipment I have ever worked with. Have never heard of cellular equipment that uses the same frequencies for uplink and downlink.
I believe the GSM standard requires different uplink and downlink frequencies also.
Or do what I do and start posting more meaningful posts to bury the bad one and hope nobody notices.
In the United States, national carriers tend to have between 30,000 and 54,000 cell sites. While this document (http://www.sprint.com/whitepapers/dbdownload/HeavyReading_Assessment_of_Sprint_s_Network_Vision_Initiative_Dec2010.pdf?table=whp_item_file&blob=item_file&keyname=item_id&keyvalue='25625ay') is mostly about Sprint's network vision, but it also has estimates (page 13) of cell sites for all the national carriers ranging from 30,000 on the low end for Sprint's iDEN network to 54,000 on the high end for AT&T's network. Given that all of the national carriers tend to cover many major cities, it seems unlikely that London would need 70,000 cell sites for 4G.
This is an article from the point of view of a company that sells small cell sites. Putting 70,000 cells in London would mean putting 115.3 cells in every sq mi. That's one cell every 5.5 acres.
In Kansas City (US), I am one of the few people who actually get 4G at home with Sprint. If I'm in a moving car and I need to use the internet, I just turn off the 4G and use 3G because that's the only way to avoid apps saying "data connection lost". So I don't know if we need 70,000 cell towers but I do think what we have now is inadequate.
Oddly enough, Sprint still seems to be the best option because dropping down to 3G is better than being cut off altogether by a bandwidth cap. And keep in mind, this is the United States so when I do bandwidth tests on 4G, I'm getting around 1.9 megabits/second. As soon as I read somebody saying LTE is faster than home broadband, I knew that person was in another country.
+1 but can't moderate with this stupid hard drive.
If we assume that there are about 7 million people in london then that means that each cell serves about 100 people IF they all have 4g cellphones. For some reason this seems a bit off. Lets assume that adoption rates are 50% so that gives us 50 people per cell. 50*100Mb/s = 5Gb/s (assuming all users are mobile otherwise we are looking at 50Gb/s which is quite a load for a single cell but assumes that all the users are pulling the max data all the time). I'm not going to do the math for antenna space and bandwidth, but this [https://www.google.com/url?sa=t&rct=j&q=number%20of%20simultaneous%20connections%20to%20a%20single%20lte%20cell&source=web&cd=3&ved=0CCsQFjAC&url=http%3A%2F%2Fwww.motorola.com%2Fweb%2FBusiness%2FSolutions%2FIndustry%2520Solutions%2FService%2520Providers%2FWireless%2520Operators%2FLTE%2F_Document%2FStatic%2520Files%2F6834_MotDoc_New.pdf&ei=7PeETrGmIo24twemp_gu&usg=AFQjCNEQ5Y_VX896_PG2lJPZK3HviwzdDw&sig2=aDM8ApeoCYBEHMbDCqbDJA] PDF white paper seems to suggest that 200 connections per cell is about maximum. So, I'd say that their math is off somewhere even given reasonable QOS requirements and 50 concurrent users. Maybe they are defining London differently?
TL;DR bad math
Right, but his argument was that there are physical filters on specific frequencies to block transmission, and my counterpoint was that any scheme that rigid and immutable would fail in America because our needs are much more dynamic and subject to change from day to day as carriers merge, acquire spectrum, and reorganize their band plans.
What exactly is P2P back-end?
Smoke and mirrors, at this point.
Kid-proof tablet..
Exactly. So killing everyone's battery isn't due to P2P back-end. Unless smoke is caused by battery being killed.
Only you don't require that kind of bandwith for talking. You require it for uploading to youtube.
You require heavy bandwidth for talking if you speak a sign language.