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In 3G, the most prevalent technology was UMTS with CDMA-2000 in close contention. All radio access technologies have to solve the same problems: to divide the finite RF spectrum among multiple users as efficiently as possible. GSM uses TDMA and FDMA for user and cell separation. UMTS, IS-95 and CDMA-2000 use CDMA. WiMAX and LTE use OFDM.
The main UMTS bands are in bold print. Networks on UMTS-bands 1 and 8 are suitable for global roaming in ITU Regions 1, 2 (some countries) and 3. Networks on UMTS bands 2 and 4 are suitable for roaming in ITU Region 2 (Americas) only. Networks on UMTS band 5 are suitable for roaming in ITU Regions 2 and 3 (single countries).
The Universal Mobile Telecommunications System (UMTS) is a 3G mobile cellular system for networks based on the GSM standard. Developed and maintained by the 3GPP (3rd Generation Partnership Project), UMTS is a component of the International Telecommunication Union IMT-2000 standard set and compares with the CDMA2000 standard set for networks based on the competing cdmaOne technology.
In contrast with GSM base stations, Node B uses WCDMA/TD-SCDMA as the air interface technology. As in all cellular systems, such as UMTS and GSM, the Node B contains radio frequency transmitter(s) and the receiver(s) used to communicate directly with mobile devices, which move freely around it. In this type of cellular network, the mobile ...
For technical details on UMTS and a list of its designated operating frequencies, bands, and their common names, see UMTS frequency bands. Networks on the global UMTS-bands 1 and 8 are suitable for global roaming in ITU Regions 1, 2 (some countries) and 3. Networks on UMTS-bands 2 and 4 allow roaming in ITU Region 2 (Americas) only.
[1] [2] [3] In 1999 ITU approved five radio interfaces for IMT-2000 as a part of the ITU-R M.1457 Recommendation. [4] The five standards are: [5] IMT-2000 CDMA Direct Spread. also known as W-CDMA, used in UMTS, the successor to GSM; IMT-2000 CDMA Multi-Carrier. also known as CDMA2000, the successor to 2G CDMA ; IMT-2000 CDMA TDD. also known as ...
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 850/900/1900/2100 MHz, and dual-band CDMA EV-DO Rev. An at 800/1900 MHz, for a total of 'six' different frequencies (though at most four in a single mode).
High Speed Packet Access (HSPA) [1] is an amalgamation of two mobile protocols—High Speed Downlink Packet Access (HSDPA) and High Speed Uplink Packet Access (HSUPA)—that extends and improves the performance of existing 3G mobile telecommunication networks using the WCDMA protocols.