GSM stands for Global system for mobile communication (GSM) is a second generation digital mobile technology system, GSM Provides for the best mobile coverage within countries and across them all over the world.
GSM system used mobile delivered a data speed of 9.6 kb/s. The upgrade pushed up data speed around 48 kb/s.
GSM uses a variation of wireless technology used like time division multiplier access (TDMA) and code division multiple access (CDMA).
GSM operates at either the 900 MHz or much high-frequency band 1800 MHz.
UMTS R4 techniques are preferred as a mobile operator, especially for those with GSM legacy network. This techniques to evolve their existing 2G GSM network. It provides a smooth path to bridge legacy TDM based network to an IP based soft switch network.
The proposed evolution path in UMTS R4 suggests three layers structure solution to seamless coverage UMTS R4 core network with a GSM core network. So can achieve the all IP version and its capable of coverage with EPC and also an IMS.
GSM networks :
GSM networks :
- T-Mobile
- AT&T
- Indigo wireless
- Pine cellular
- TerreStar