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Speculating On the Far Future of Cellphones
Trio writes "What will cellphones look like in in future? silicon.com explores five future characteristics that could shape tomorrow's phones — from a wearable prototype such as MIT's SixthSense device which projects mobile data into the user's world, to a mobile that mixes the real and the virtual by using holographic telepresence. So far, so futuristic, but one question remains: will there be enough spectrum to support all this wireless communication?"
Then again, due to radiation from nuclear fallout, cell phones and other electrical devices will be useless. We'll return to carrier pigeons. No wait, they would have died off too. Maybe we will have to actually see the person we're talking to then. What a concept!
First of all, to transmit on wide ranges of frequencies at high power costs a TON of money in electricity. I've researched what a radio station (5000 watts) alone has to pay for a slim band of frequency, and it's not trivial at all.
They transmit at such a high power so as to achieve good coverage over the entire city they're serving. If the signal only had to be heard over a radius of a few kilometres or less, such as with a cell tower, then the tramsit power could be reduced greatly. Although FM is not a particularly power-efficient or bandwidth-efficient modulation scheme (in fact, considering the large guard bands between FM radio channels, the overall bandwidth efficiency is pretty bad), but 5kW power consumption is nothing in the grand scheme of things. Heck, a typical air conditioning unit consumes about 1kW. I'm pretty sure some FM transmitters use up to 10s or 100s of kW, but that's still probably less than your average office building.
The reality is that in the biggest chaos, it isn't the strongest that survive, it's generally the weakest groups that make it. Look at hurricanes (VERY strong, but don't last) versus slightly windy weeks. It's not the strong that maintain for long.
The analogy flew over my head completely.
In the airwaves industry, we have so many proofs of things going right. I know people will cry foul if I say "What about WiFi?" but with WiFi, we have a VERY slim band of frequency that is working VERY well except in the most congested areas. What, in those areas, we had tripled the amount of frequency range? What if we quadrupled it? Again, it's the State's regulations, not WiFi, that breaks that most congested area.
Eh? The Wifi band (2.4 to ~2.5 GHz) is about 100 MHz in width. By no means is that "very slim" in any sense of the word. By comparison, the FM radio band (88 to 108 MHz) is only 20 MHz in width. Now it's kind of apples and oranges to be comparing a long-range broadcast voice service to a short-range broadband data service, but, by any objective measure, 100MHz is a big chunk of spectrum
All those people who have TV and radio now would still have it, but they'd get it on-demand, a la carte. Broad-casting is efficient only in spectrum, it is terribly inefficient in time scheduling. It's lost completely in terms of data analysis to see who is watching/listening to what and when (Nielsen is a failure, really). Since few people can truly watch TV, listen to the radio, talk on the phone, and browse the web at the same time efficiently, most of the spectrum in their given area set for a given service is WASTED. When you are watching TV in your living room, what is happening to all the AM and FM spectrum? Wasted. Cell phone channels? Wasted. It's endless to think of the spectrum being wasted in your given area right now with useless transmissions that are actually using energy to be transmitted to you and not received.
We won't need 50,000 watt radio stations anymore, when a 2 watt transmitter/receiver in your locale will cover so much more, so much more efficiently. And what if no one is using a given set of frequencies at a given time? We can throttle back the transmitter power -- saving energy, saving money.
I say bring on the anarchy, it'll REDUCE the chaos. Especially in terms of the airwaves.
You should probably confine your arguments to bandwidth efficient spectrum utilization because the "wasted power" is, again, a drop in the bucket. Not to rain on your parade of wireless utopia via shared spectrum anarchy, but it will be a huge technological challenge to equip all wireless devices with the ability to privately negotiate channel allocations with competing devices while ensuring fairness and reliability. For example, let's say demand for cellular channels ramps up around dinner time. The spectrum is already full though, so what do you do? Users of other services will have to be heavi
I can imagine a similar discussion in 1875: "What will telegraphs look like in the future?"
Actually, the view from 1875 was surprisingly clear. Because, by 1875, telegraphy was a mature technology.
It was generally recognized that a "printing telegraph" was desirable. But it was hard to do. The House Printing Telegraph dated from 1852. Early machines had trouble staying in sync. By 1875, though, there were reasonably good printing telegraphs and stock tickers, using a design by Phelps.
The sending and receiving gear then stagnated for decades. Progress was made in transmission, but the end node technology was relatively static for years. It wasn't until 1921, with the first Teletype machines that worked, that a new technology replaced the old one. The reason was manufacturing technology. The Phelps machines had a relatively low parts count. Teletypes had perhaps 5x as many parts. Until manufacturing techniques improved, page printers were just too much machinery to build and deploy in quantity.
Once Baudot-code teletypes, with associated paper tape punches and readers, were developed, the technology started to move forward again. Messages could at last be forwarded without manual retyping. Forwarding still required people tearing off sections of paper tape from punches and moving them to readers. It wasn't until 1948 that Western Union Plan 55-A produced a fully automatic message switch. (It was entirely electromechanical, with many paper tape readers and punches, and switchgear to interconnect them. Think Sendmail built from moving parts.)
Not until 1977 did Western Union finally get rid of the last of the paper-tape switching centers. By then, telegrams were in decline anyway.
In the U.S., we have the slow, bureaucratic and oligarchic FCC that limits technology from acquiring near limitless spectrum/bandwidth.
I don't listen to radio in the car, so radio spectrum is useless. So much that we do today would be better suited to a HUGE amount of spectrum divvied up and utilized by every device that could hop frequencies as needed to find a clean channel, that could raise power needs when a tower is far but drop them significantly when towers are near.
Yes, if we had a small, agile, more commercial FCC who respected modern technology then they would be immune to the laws of physics and information theory (never mind that they might care about people other than you).
The AM and spans from a few hundred KHz to 1.5 MHz or so. Yuo won't get much bandwdth out of that one. I assume you know why bandwidth is called bandwidth and how it related to frequency bands. Plus have you ever disassembled a radio? The aerials in AM radious are HUGE. If you want to carry one of those around in your cell phone, be my guest...
Sure, you could make better use of the limited spectrum by using long wave digital channels. But frankly, why bother?
The same goes (but a little less so) for FM. It's still low fewquency. By the time you get up to 5GHz, the entire analog radio spectrum fits comfortably within one or two small bands.
There's just not enough space taken by radio to care about.
SJW n. One who posts facts.
IMHO, among the best post-cyberpunk style science fiction series to explore this, among other concepts, in recent years has been the Ghost in the Shell: Stand Alone Complex series. The "cyber brain" conversations combined with "external memory" (think of it like an off site storage, backup and messaging server for your mind) really takes man machine integration to its final logical conclusion: making or receiving voice and video communications remotely is as easy as initiating thoughts to do so. Although, I do think that the series is a bit too optimistic on how soon all of this will actually come about (i.e. by 2030).