GSM vs. CDMA
GSM can refer to 2 things
1. Global System for Mobile Communications - a specific communcation standard
2. Any standard adoped by the GSM foundation as the "global standard for mobile communications" including GSM, GRPS, EDGE, UMTS, HSPA, HUSPA, HUSPA+ , LTE and LTE Advanced
CDMA can refer to 3 things
1. Code Division Multiple Access - a channel access method imployed in many different broadcast technologies, including GSM standards UMTS, HSPA, HUSPA and HUSPA+
2. IS-95 or CDMAone a specific communication standard developed by Qualcom, commonly refered to as "CDMA" because it was the first standard to use the CDMA chanel access method
3. Any version of the Qualcom standard and it's revisio...
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deepskyblue said:
So my answer to the question "is CDMA (the qualcom standards) better?" --not any more
Who even asked this?
If you had asked anyone here which of the two was better, I think you'd find most people in this forum think there are merits to both, but GSM makes the most commercial sense. Logically, the transition of most carriers to LTE is an extension of that "common sense."
You're talking about the remnants of decisions made ten years ago when carriers were either CDMA or TDMA. Neither had a clear advantage over the other, so decisions to continue or alter technology were made based on what was known at the time. Now, ten years later, we're about to watch the slow transition of mo...
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Or CDMA will handle increased data usage better than GSM.
I disagree. I tried very hard to provide an objective presentation of why I think this and also why statements like that are ambiguous in nature.
It seems like it came out of their you-know-what.
https://www.phonescoop.com/carriers/forum.php?fm=m&f ... »
And as I remember you had your a** soundly handed to you by Cellstudent on anything technical.
Considering Verizon and Sprint and EVERY other major CDMA carrier in the WORLD are moving beyond the technology, you're arguments are several years too late.
So to answer your question, CDMA was clearly the superior technology when the companies had a choice between the two. Now that there is a better option, those companies are choosing differently.
Menno said:
You posted something very similar to this months ago.
And as I remember you had your a** soundly handed to you by Cellstudent on anything technical.
Ahh.. that was fun, wasn't it?
you posted just about a week ago that if verizon got the iphone that it's network would just handle it because CDMA is so awesome. I think that's ignorant for a number of reasons that i don't need to go into now.
There has been a superior technology for a number of years called UMTS, CDMA (EV-DO) hasn't been competitive in terms of speed since it came out. So verizon dosen't just go with the best standard whenever it comes out because they skipped that one.
IS-95 and companies electing to use it I think is akin to sprint picking out wimax for their 4G buildout. It really just provides short term benifit and has a set of drawbacks that come with it as well.
Really? Are you arguing about a decade old decision? Are you going to go back into history and argue about gasoline next? Or alternating current? Or the standard light bulb base?
https://www.phonescoop.com/carriers/forum.php?fm=m&f ... »
🙂
1) They will only acquire a small fraction of AT&T's user base so the strain will not be overwhelming.
2) Calls don't drop when the data network saturates. People are far less likely to complain about buffered data sessions than dropped calls.
Verizon went with CDMA before an iphone EXISTED
They completed upgrading to revA in 2007
UMTS was the GSM carriers trying to shoehorn CDMA tech onto their GSM networks and it's INSANELY inefficient.
At the time, EVDO was the SMARTEST CHOICE. Which is why in EVERY country where wireless tech is not Government mandated EVDO has a significant if not superior presence.
CDMA is significantly better than GSM was and EVDO allowed a nationwide 3g rollout, UMTS didn't. So again, it's superior. If you're arguing that speed is everything you don't understand Verizon's business model.
If it took you WEEKS to regurgitate the SAME false information, you should consider just not posting.
QUOTE: Verizon went with CDMA before an iphone EXISTED
-I don't recall saying otherwise?
QUOTE: UMTS was the GSM carriers trying to shoehorn CDMA tech onto their GSM networks and it's INSANELY inefficient.
-I kind of think that this kind of implies that qualcom owns that channel access method. They didn't invent the CDMA channel access method they just used it first.
Could I not also say that verizon deploying LTE and not UMB (the now defunct Ultra Mobile Broadband Qualcom was developing to replace EVDO) is an admission of the qualcom's inferiority to current GSM association standards?
and really "INSANELY inefficent"?? maybe slightly less efficient would be a better ...
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So yes, INSANELY less efficient. It's not cost effective, isn't not spectrum effective. The ONLY reason UMTS saw such widespread adoption was because countries were locked into developing on outdated GSM tech because they were required to by their government. UMTS is a Crap technology because it's not efficient cost wise or how it handles data. So yes, EVDO is still technically "Better"
Now, if you compare it to HSPA+, then the speed differential is signifi...
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UMTS made sense for AT&T.
I think we're making some of the exact same points that we're not in disagreement about.
I mentioned all the benefits you're mentioning of the qualcom deployments in my original post. I acknowledge that those are benefits.
I mentioned the exact same drawbacks you're mentioning to UMTS deployments.
If you're comparing purely the merits of the standards i think EVDO is only competitive with the earliest versions of UMTS, (HSPA and and HSPA+ are UMTS revisions.)
If you're comparing qualcom versus the gsm association i don't think qualcom ever stood a chance.
What you seem to be making you points from is the big picture political economy of the wireless industry and bus...
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I don't like people stating that the qualcom standards are better as if the companies that didn't go with them made a mistake.
I had been used in satellite broadcasts for years before qualcom decided it would be a good idea to use it in their cellular standard.
Qualcom was absolutely right. But at the time that companies made the jump to qualcom it was much less clear what the uses and consumer needs for cellular data would be.
By the time that those needs became more mainstream the GSM association had standards that could meet those needs as well.
What if there was no qualcom? Would we be using spread spectrum and multiplexing in cellular technologies without them? Absolutely.
Many of the enhancements in LTE are borrowed from computer networking. The GSM association mem...
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here's a hint: it has nothing to do with how the actual technologies worked.
Seriously, Go back to the ATT boards. At least you can pretend to know what you're talking about there.
I sense a lot of brand pride emanating from your general direction.
Your replies are more insult than rebuttal.
I think it's possible to discuss these things with out resorting to name calling.
I just don't feel this part of the thread is going anywhere so I'm not going to indulge your 2 sentence "what about this? what about this? you're a moron" replies.
If you don't feel like you can participate in the discussion in a real way then don't.
I don't have to participate in this discussion because there is no discussion. A discussion requires two parties talking about the same thing. You keep changing the subject whenever someone points out the flaws in your logic. That's not a discussion
Every few months you start a post or two here spouting off something about how you don't like CDMA, or how Verizon is admitting their flaws about tech choices by going with LTE, or whatever crap that they teach you to say in webinars. That's NOT you loo...
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But Verizon must come back to the global standard with it's tail between it's legs. 🙂
It was the way Verizon was run, rather than the technology they used, that brought Verizon great success.
Your image implies that Verizon has regret for something, which it doesn't. It's excited to bring LTE to market and show people what can be done with it. This isn't about phasing out some technology it regrets ever choosin...
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More who comments like that are directed towards are verizon reps stating the the qualcom standards are better like AT&T made a mistake by not implementing them.
I don't think either company made i mistake. I think they both made the right descisions based on their busniness strategies.
Sprint went with wimax for their 4G buildout not because it was the best 4G standard available, but because they wanted to have the first 4G network. So from the standpoint of their business strategy, wimax is a success. As a company they've been doing better lately too (although i still think we'll see them file for bankruptcy in the soon future) so even if they switc...
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deepskyblue said:
Here's my 2 cents:
CDMAone and CDMA200 have had benifits and drawbacks for the companies that have elected to carry them but in the whole scheme of things they represent dying niche technology . When CDMAone came out it was faster, it had higher capacity per cell and had better range.
Modern GSM standards (UMTS, HSPA, HUSPA, HUSPA+ and LTE) employ the same "spread spectrum" technology as the qualcom standards and have inherited the benifits - speed, range, and capacity; and the draw backs - decreased range under load, etc.
[gobbledegook]
So my answer to the question "is CDMA (the qualcom standards) better?" --not any more
You're not compa...
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I'm not comparing channel access methods.
Qualcom didn't invent the CDMA channel access method, they were just the first to use it in a cellular broadcast technology.
I don't know the 1xRTT is the clear winner for voice. What are you basing that on? The bitrate (quality of the digital representation of a person talking) is lower than on the GSM association standards.
Most users on GSM assocation networks are not using EDGE for voice, they're using UMTS which does voice and data.
deepskyblue said:
I don't know the 1xRTT is the clear winner for voice. What are you basing that on? The bitrate (quality of the digital representation of a person talking) is lower than on the GSM association standards.
1) Soft-handoff, fewer dropped calls or missed packets.
2) High compression rate, more simultaneous users per channel.
3) Cannot be disrupted by excessive data traffic, unlike UMTS implementations. (I guess theoretically it could be, but that would take astronomical amounts of signalling traffic from data users, even by today's standards).
4)Low bitrate in 1xRTT is compensated by having superior demodulation techniques.
Digital transmission systems employ two major concepts: Tr...
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UMTS supports soft handoff just like CDMA 2000.
As far as not being affected by data usage I don't think that's true. Anything using code division multiple access runs into issues with the noise floor. Since all the sessions are happening at once they're just accompanied diffenent encodings that all get sorted out in the backend, the mess of signals during heavy load decreases the operable range of the tower. There is a limit to the ammount of sessions that can be suppored by the cell and there is a limit to the number of sessions that can be processed by the backhaul.
I think voice can be affected by heavy load on...
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You're providing NOTHING to back up your arguments, and you're asking us to do the legwork to refute your claims.
If anything, it's ad admission that actually doing the work and finding the answers would be wasted on you.
deepskyblue said:
As far as not being affected by data usage I don't think that's true. Anything using code division multiple access runs into issues with the noise floor.Since all the sessions are happening at once they're just accompanied diffenent encodings that all get sorted out in the backend, the mess of signals during heavy load decreases the operable range of the tower.
This might be true for Sprint, but it's not really relevant for Verizon. Sprint has all of its CDMA assets tied up in the 1900 MHz block, so they have to share 1xRTT spectrum adjacent to or...
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So it sounds like using different spectrum isn't something that's specific to qualcom systems, and any deployment could used voice and data at different frequencies.
Also it sounds like data could affect voice on the backhaul since i'm assuming that they still share backhaul.
I think you're at least somewhat misrepresenting UMTS in the way it addresses QoS issues. It sounds like from what you've posted that UMTS does nothing to address QoS or that call quality is affected as soon as there is load on the tower, that's not true.
Voice and data are prioritized differently in UMTS systems. As load increases data is automatically throttled to prevent it from affect...
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deepskyblue said:
So it sounds like using different spectrum isn't something that's specific to qualcom systems, and any deployment could used voice and data at different frequencies.
Remember this post:
https://www.phonescoop.com/carriers/forum.php?fm=m&f ... »
That's where you changed the conversation from "Qualcomm vs. Earth" to "Verizon with iPhone vs. AT&T." Now you want to talk about Qualcomm vs. Earth again. Please stop changing subjects. Commentary on the general case will always apply to AT&T vs. Verizon, but commentary on AT&T vs. Verizon is almost totally irrelevant to Qualcomm Vs. Earth.
Also it sounds like data could affect voice on the backhaul since i'm ass...
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EDGE and UMTS can't share bands, they interfere with each other. So while AT&T also has the convented 850 band it has to be used exclusively for EDGE and the 1900 band is used exclusively for UMTS.
Check the QoS for UMTS systems there are actually 4 different classes of prioritization. The first class is voice and it gets everything, the other 3 classes would be capped down to a trickle if the voice demand was high enough. Then if voice has 100% of needed band then the next class can use all the band it needs, if that class has all it needs then the next class can have all it wants and so on. Not all nodes are creat...
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deepskyblue said:
...AT&T also has the convented 850 band..
I didn't know they let bands into the convents!
deepskyblue said:
The biggest factor hurting voice quality on the AT&T network is the iphone, but not because it's overloading the network. It's because the phone has terrible reception and drops calls like nobody's business. 95% of the the calls (think call center) I take where the customer's issue is dropped calls are iphone users. Outside of the iphone I hear about them maybe once a week from users of other phones.
This would be one more argument that Verizon would probably not suffer significantly with the introduction of an iPhone. A CDMA variant would have to have the antenna system completely redesigned by a CDMA engineer, rather then the haphazard crop of GSM engineers they appear to be employi...
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Apple's response? Not our problem.
They set out to fix the known handoff problem from the first 3 iphones with the iphone 4 and ended up with 2 external antennas that attenuate the signal when people hold the phone.
I don't have a lot of confindence in their engineering teams myself.
The origional deal with Verizon fell apart because they wouldn't bend to apple's demands.
What if verizon said "hey we're not taking this phone it has reception issue you're going to have to fix it." And apple's response was "we're not fixing it, we'll take it to sprint."??
I wish AT&T would have had the balls to say that...
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deepskyblue said:
The origional deal with Verizon fell apart because they wouldn't bend to apple's demands.
What if verizon said "hey we're not taking this phone it has reception issue you're going to have to fix it." And apple's response was "we're not fixing it, we'll take it to sprint."??
I wish AT&T would have had the balls to say that to apple back in 06. We won't even defend ourselves publicly. That phone has caused trememdous damage to our reputation.
It's very unlikely that Verizon would tolerate a flagship phone with such glaring mechanical failures. Verizon leadership puts a tremendous amount of value on their brand. They won't stand for it.
But that's only part one. Part two is th...
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