In reference to cell phones what does GSM, TDMA and CDMA mean?

Answer 1

These are the types of networks that the phones are running on. It's their technology. GSM works with Cingular, T-Mobile and most of your phone systems outside of the US (SIM card based). TDMA is an older techonolgy, not used much. CDMA is what your carriers like Verizon, Sprint/Nextel and USCellular run on.

Answer 2

I think this will help if you want to read up on it.

TDMA
TDMA is the access method used by the Electronics Industry Alliance and the Telecommunications Industry Association for Interim Standard 54 (IS-54) and Interim Standard 136 (IS-136). Using TDMA, a narrow band that is 30 kHz wide and 6.7 milliseconds long is split time-wise into three time slots.

Narrow band means "channels" in the traditional sense. Each conversation gets the radio for one-third of the time. This is possible because voice data that has been converted to digital information is compressed so that it takes up significantly less transmission space. Therefore, TDMA has three times the capacity of an analog system using the same number of channels. TDMA systems operate in either the 800-MHz (IS-54) or 1900-MHz (IS-136) frequency bands.

CDMA
CDMA takes an entirely different approach from TDMA. CDMA, after digitizing data, spreads it out over the entire available bandwidth. Multiple calls are overlaid on each other on the channel, with each assigned a unique sequence code. CDMA is a form of spread spectrum, which simply means that data is sent in small pieces over a number of the discrete frequencies available for use at any time in the specified range.

Answer 3

Here's the GSM from Wiki

Global System for Mobile Communications (GSM) standards define certain codes that (if implemented by the particular carrier) make it possible to query and set certain service parameters (e.g., type of Call forwarding) from mobile devices (GSM cell phones

And the TDMA

Time division multiple access - a system used for radios and cell phones
the initials TDMA (from the initialism for "time division multiple access") are also used in the United States as a name for the mobile phone standard more properly referred to as IS-136 or D-AMPS

maybe you could use Wiki ?

http://en.wikipedia.org/wiki/Main_Page