merry, here is a reply to those comments as reported on the bull:
"i-yi-yi "...since they available freqs are in such limited supply (for TDMA/GSM). The total number of timeslots a particular cell can support compared to the number of potential users determines how many cell towers the carrier needs to build to cover their customer base...Enter CDMA - now without boring you with half remembered technical details...The net of this is that carriers can cover more customers with a lot fewer towers. The number I remember was on the order of 12 times fewer towers, but it was a long time ago and I don't remember 100%. The bottom line is that carriers using CDMA can build their networks more cheaply..."
He's only partially accurate on two counts:
(a) He is correct in defining the time slots. The bottom line, or major factor for choosing TDMA/GSM in the part of the equation as he calls it in the phrase, "compared to the number of potential users." If you're serving a geographical area with "potential users" being a known quantity (or at least a quantity that is projectable), then the bottom line is you go with the system which costs less per known user over time. In Latin America, for example, the known users per given area were known; the TDMA systems installed were very capable of handling the known users in those given areas. CDMA was good for areas with "bursty" traffic where user traffic at any given time was an unknown and growth per cell was exploding beyond system capabilities. Fortunately for GSM/TDMA systems, they've been able to upgrade the systems to handle 10X plus analog (some Euro systems are capable of going as high as 15X - same as CDMA).
(b) His assumption that because you need "less antennas" the system is "less costly" is dependent on two variables; (1) the cost of the overall network per antenna served and (2) the number of "known" users per cell. The overall CDMA system, including antennas, (don't know where he came up with 12 X fewer since this is really off base) per cell is much more expensive per user than TDMA or GSM sytems (some up to 3X more expensive depending on the area served per user served). CDMA retains the intial increased cost back by offering additional services (if it can) and charging for those additional services (at least it has the potential to do so).
As CDMA and TDMA/GSM progress toward the future the number of users in the cell phone environment are expected to increase. At the same time, TDMA/GSM has been developing new technologies to meet those growing demands so that system strain and addtl cost of buildout is minimalized. CDMA (WCDMA) is also progressing toward 3g and is capable of handling all the data specific and multimedia capabilities our modern age requires on a wireless base.
this has been answered many times before in previous posts. CDMA supposedly retains their cost over time with the ability to add additional services and still retain quality service. Nevertheless, if your needs are only "X", and you can afford only "X" for the forseeable future(volkswagen - TDMA), why should you go for "Y" (cadillac)?
The beauty of the WCDMA system is that it proposes to cost slightly more than current GSM systems, yet deliver much, much more. Current WCDMA buildout costs have been kept under significant scrutiny; so analysts who make known or project such costs are doing so by hearsay within the community. Qualcomm will tell you that WCDMA will cost more than CDMA2000. NTT and Nokia, on the other hand, when you visit them, clearly claim the opposite. They claim to be a year ahead of Qualcomm in the WCDMA vs CDMA2000 race. I've rarely known a Japanese businessman to boldface lie or brag (can we say the same for Americans?); so I do tend to believe statements from NTT (Nokia is no different - very conservative in their comments)."
and
"bottom line Grube is that (a) CDMA systems are NOT less costly than TDMA systems per cell. Support for CDMA comes from "costs over time" and "exploding cell" population; and a number of other factors.
TDMA has become the technology of choice in India and Latin America. Ask yourself why this is. Some of the answers are there in the previous post.
Why has T stated so strongly that they plan to stay with TDMA? Why did NEC drop CDMA plans for the US and go with TDMA only? On and on and on. Either these engineers at these companies are idiots or, as stated previously, a number of variables are involved beyond the fact that CDMA can serve a greater number of users per cell.
CDMA can serve a greater number of users currently. But, if you have only 10 known (extreme example) users in that cell, are you going to spend $2200 or $600 per user to install (all other variables being equal)?
TDMA/GSM/PDC technology is also expanding to serve a greater number of users per cell. If this were not so, the TDMA hybrid would not be part of the 3g standard."
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