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Unlimited cell size, low transmitter power permits large cells Very low density Soft No 3G: CDMA: IS-2000 (CDMA 2000) Digital: 2000 / 2002 Limited RUIM (rarely used) None Unlimited cell size, low transmitter power permits large cells Very low density Soft No EVDO / Yes SVDO [2] 3G: W-CDMA: UMTS (3GSM) Digital: 2001 Worldwide SIM card: None
TDMA frame structure showing a data stream divided into frames and those frames divided into time slots. Time-division multiple access (TDMA) is a channel access method for shared-medium networks. It allows several users to share the same frequency channel by dividing the signal into different time slots. [1]
The performance of each technology is determined by a number of constraints, including the spectral efficiency of the technology, the cell sizes used, and the amount of spectrum available. For more comparison tables, see bit rate progress trends , comparison of mobile phone standards , spectral efficiency comparison table and OFDM system ...
The access method used for IS-54 is Time Division Multiple Access (TDMA), which was the first U.S. digital standard to be developed. It was adopted by the TIA in 1992. TDMA subdivides each of the 30 kHz AMPS channels into three full-rate TDMA channels, each of which is capable of supporting a single voice call.
In the GSM cellular mobile phone standard, timing advance (TA) value corresponds to the length of time a signal takes to reach the base station from a mobile phone.GSM uses TDMA technology in the radio interface to share a single frequency between several users, assigning sequential timeslots to the individual users sharing a frequency.
The North American Standards IS-54 and IS-136 were also second-generation (2G) mobile phone systems, known as (Digital AMPS) and used TDMA with three time slots in each 30 kHz channel, supporting 3 digitally compressed calls in the same spectrum as a single analog call in the previous AMPS standard. This was later changed to 6 half rate time ...
The most common 2G technology was the time-division multiple access (TDMA)-based GSM standard, used in most of the world outside Japan. [citation needed] In North America, Digital AMPS (IS-54 and IS-136) and cdmaOne (IS-95) were dominant, but GSM was also used.
For example, one version of the Nokia 6340i GAIT phone sold in North America can operate on GSM-1900, GSM-850 and legacy TDMA-1900, TDMA-800, and AMPS-800, making it both multi-mode and multi-band. As a more recent example the Apple iPhone 5 and iPhone 4S support quad-band GSM at 850/900/1800/1900 MHz, quad-band UMTS/HSDPA/HSUPA at 850/900/1900 ...