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Domain: umtsworld.com
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Comments · 15
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Re:Oh, that's what they do?
The biggest differentiator between an iPhone and an iPod Touch is the 3G radio. Guess who didn't develop GSM tech, but doesn't adhere to the licensing terms offered by the developer? I guess it's a case of [Apple] doing whatever the hell they please because they have no appreciation for the hard work of [Nokia].
If we're talking about 3G..... Nokia? WTF? Nokia?!?
It's Qualcomm, not Nokia. When it comes to 3G, know who to appreciate, dammit.
Maybe you need a history lesson.
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justification of cost on 3G networks
As a little followup: I use my phone exclusively in UMTS mode, so I'm never using the GSM network with it's transmission of SMS through the expensive paging channel. In UMTS, as I'm sure is the case for all of the 3G networks, SMS is just treated like any other low priority data, so the justification for charging more for transmission loses its meaning. I wonder if the telecom companies plan to keep charging so much for SMS long after the "need" to charge for it has evaporated (actually, I'm sure that they will).
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Re:cell phones and microwaves
and cell phones just so happen to use the same frequency of 2.4GHz to trasmit. So one would question the use of cell phones, since the frequency is the same
Interestingly, this is a bunch of crap. GSM frequencies are GSM-900 (890 - 915 MHz up, 935 - 960 MHz down), GSM-1800 (1710 - 1785 MHz up, 1805 - 1880 MHz down), GSM-850 (824 - 849 MHz up, 869 - 894 MHz down), GSM-1900 (1850 - 1910 MHz up, 1930 - 1990 MHz down) and GSM-400 (450.4 - 457.6 MHz paired with 460.4 - 467.6 MHz, or 478.8 - 486 MHz paired with 488.8 - 496 MHz). Up means from the mobile to the cell, down means from the cell to the phone.
(Source: http://www.answers.com/topic/gsm-frequency-ranges) CDMA/UMTS:
1920-1980 and 2110-2170 MHz Frequency Division Duplex (FDD, W-CDMA) Paired uplink and downlink, channel spacing is 5 MHz and raster is 200 kHz. An Operator needs 3 - 4 channels (2x15 MHz or 2x20 MHz) to be able to build a high-speed, high-capacity network. 1900-1920 and 2010-2025 MHz Time Division Duplex (TDD, TD/CDMA) Unpaired, channel spacing is 5 MHz and raster is 200 kHz. Tx and Rx are not separated in frequency. 1980-2010 and 2170-2200 MHz Satellite uplink and downlink.
(Source: http://www.umtsworld.com/technology/frequencies.ht m)TDMA/AMPS:
AMPS operates in the 800 and 1900 MHz
(Source: http://en.wikipedia.org/wiki/IS-136)The closest thing is 2.2 GHz. None of them use 2.4GHz. At least, not that I can find. Now, Wireless ethernet, that's 2.4GHz. Well, most of it.
What I am getting at, is that from what I've been told, cell-phones can produce the same affect as microwaves, and really mess with the water in your brain, and supposedly cause cancer.
Any wave between 1GHz and 300GHz (30cm to 1mm wavelength) is a microwave. Maybe you meant microwave oven? It's important to make the distinction when you're talking about these things.
It seems to me elevation is of more importance than whether or not the two cell phones are communicating directly.
Elevation is 100% irrelevant. Not all cellphone towers are on mountains (though they certainly are here, where I live, in Lake County, California, USA, Terra) and the only important thing is the distance to the tower. Don't worry about the current, worry about the power of the transmission. All current portable cellular phones are under 1 watt. Most flip phones are under half a watt. The only reason anyone is worried about it at all is that it's very close to your head.
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Re:Bah, beaten to it by years
beaten by over 3 years!
http://www.umtsworld.com/lastword/lw0041.htm -
Re:iDen to Go?From a technology point of view there are certain limitations that cannot be overcome. GSM was standardized in Europe by goverment control because they thought CDMA was imposible. Then Qualcomm developed the technology. It is much more efficient. So when it comes to fast data transmission, CDMA has more room for improvement. That means more customers, talking and sending data at the same time at a faster speed = profit. As of now GSM is still good enough, but in the future the US GSM companies are already looking at UMTS, which is CDMA based = big costs converting a lot of infrastructure, make no mistake they will pass that on to customers one way or another.
This is a good read with illustration and such: umtsworld
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Re:Mobile Phones
Is CDMA somehow related to 3G (UMTS)?
Yes - UMTS uses "Wideband CDMA", as per this page on the UMTS World website.
CDMA and TDMA are different low-layer air interfaces; 2G systems use either TDMA or CDMA, as per the Wikipedia article on 2G. (Note that GSM uses TDMA, so it's not as if something is GSM, CDMA, or TDMA. GSM and IS-136 a/k/a D-AMPS use TDMA; IS-95, a/k/a cdmaOne, uses CDMA.)
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Re:Mobile Phones
in case anyone else thought strictnein got his billions and millions mixed up..
This page shows you that latest numbers are 70% of subscribers use GSM, 12% CDMA.
Incidentally, the US are the heaviest users of mobile tech - 458 minutes per month on average!
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Re:But what about CDMA2000?
3G is more than a '3rd generation GSM'. There are several air interfaces (basestation to mobile interface), of which CDMA plays a huge role. WCDMA, cdma2000, and TD-SCDMA all use CDMA, and yes, they are all 3G.
You can say that some 3G networks are based on a 3rd generation GSM, in the sense that the core network (basestation to public network) is an evolution of the 2nd generation GSM core network.
See here for more: UMTSworld
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Re:But what about CDMA2000?
3G is more than a '3rd generation GSM'. There are several air interfaces (basestation to mobile interface), of which CDMA plays a huge role. WCDMA, cdma2000, and TD-SCDMA all use CDMA, and yes, they are all 3G.
You can say that some 3G networks are based on a 3rd generation GSM, in the sense that the core network (basestation to public network) is an evolution of the 2nd generation GSM core network.
See here for more: UMTSworld
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Re:Please take my advice
In theory, it is a good idea, but it is only "widely accepted" (pronounced: "anticipated") by programmers who have been talking trash about Flash usability and want to play with vector art without losing face.
SVG has wide usability and even popularity in tasks far beyond Flash's ability. For instance SVG is the standard display format for geographical applications. SVG is used for some scalable KDE icons. SVG can be natively produced using open source software on open source operating systems. SVG is going to be embedded in the next generation of cell phones. SVG is going to be embedded in upcoming printers as a page description language. It is possible to print to SVG as you might print to Postscript or PDF. It is also possible to directly render PDF to SVG. And you will soon be able to output Visio diagrams as SVG. I've even heard of an SVG front-end for NetHack.
The point is that SVG can achieve popularity much greater than Flash's without displacing a single Flash animation. And once it has done that, it will be a small additional step to wipe Macromedia's proprietary, binary crap off of the face of the earth.
By all means, use Flash for the time being. It is the best tool for many jobs. But don't think that SVG is a "theory." It is used by thousands of people in practice, in both commercial and open source projects. There are many businesses dedicated to building SVG tools, and whole industries being re-imagined around SVG. Its recent growth curve is amazing and I'm convinced it will be remembered as being as important as other major W3C specs such as XML and HTML before it.
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Re:Forget about 3G! Take a look at SOMA Networks.
Interestingly FOMA is a 3G network. More specifically it is also a WCDMA network (NTT just had to do their own derivate), which
someone claimed to be inpracictable or expensive at best. -
Re:Forget about 3G! Take a look at SOMA Networks.
Interestingly FOMA is a 3G network. More specifically it is also a WCDMA network (NTT just had to do their own derivate), which
someone claimed to be inpracictable or expensive at best. -
Re:80% italy - why?
Infrastructure's a major business, and one which Nokia and Ericsson have a major degree of control over.
In 2G, market share by value of contracts (with some selected competitors for comparison) (Source: Merrill Lynch 4th Jan 2001):
GSM:
Nokia+Ericsson: 59%
Lucent: 4%
Motorola: 18%
Nortel: 12%
TDMA:
Nokia+Ericsson: 61%
Lucent: 12%
Motorola: 0%
Nortel: 18%
In 3G (remember this is infrastructure), again with selected competitors as of April 2002 (source)
Nokia+Ericsson: 64%
Lucent: 3%
Siemens/NEC: 19%
Nortel: 8%
Alcatel: 4%
Motorola: 1%
Also remember that Verizon are owned by Vodaphone who will want to use their existing European-based suppliers for GSM migration, and US carriers such as Cingular are already giving their GSM migration work to European firms like Nokia. -
Re:Minnow says "Hey we will win">The phrase "widely optimistic" comes to mind.
"Biased" is another word. Or maybe "rant".
On the RF-level, he raves about the advantages of CDMA over TDMA, without mentioning any deficiencies of CDMA.
Granted CDMA has a higher capacity.
But he fails to mention breathing cells.
Criticising Ericsson with the words:
[...]Ericsson, went through the three classic stages of Not Invented Here syndrome:
1. It's impossible.
2. It's infeasible.
3. Actually, we thought of it first.
and later stating
CDMA and TDMA are fundamentally incompatible and there's no way to create a new system (which they're calling WCDMA) which can support existing TDMA handsets. It's technically impossible for the new standard to be backward compatible.
Sounds like phase 1 of NIH.
Having a look at UMTS World and a look at the news on the frontpage (emphasis mine):
[...]
BLUETOOTH WCDMA CALL: Qualcomm announces worldâ(TM)s first Bluetooth WCDMA (UMTS) and GSM Voice Calls. [...]. (1/10/02)
[...]
GSM - WCDMA HANDOVERS: Ericsson announces the first live, dual mode WCDMA/GSM calls with seamless handover between the two modes.
[...]
Later, he is admitting it is possible on the mobile, but not feaseable. (NIH Phase 2). But impracticable on the infrastructure. You have to install a new one.
Partially, correct. There have to be installed new Base Tranciever Stations. But hardly a new complete infrastructure. The whole GSM "back-end" is compatible.
In what way is that more inpracticable than installing a new "back-end" for the higher level functions? Which he says, can easily added to CDMA2k.
Lastly, which users are looking at the baseband-specification, when buying a mobile?
The reason for the advantage of Japan and Europe is at a higher level. Availability and acceptance of services. Ease of use. -
3G data speeds
In USA there are two paths to 3G type services GSM1900 - GPRS - EDGE -(WCDMA?) and cdmaOne - cdma2000_1X - cdma2000_3X
See the possible data speeds
Cingular for example has gone the EDGE route