Umts Introduction
UNIVERSAL MOBILE TELECOMMUNICATIONS SYSTEM
UMTS
3GPP/UMTS was built having as basic purpose to offer users, transfer speeds up to 2Mbps, so they could have the ability to use applications that were not reachable due to limited capacity and transfer speed as quick access to internet, teleconference and many others. The standardisation of 3GPP for UMTS was focused mainly in three areas, i.e. services, air-interface and core network access.
Some of its most important advantages offered are [32]:
• Video-conferencing • High transfer data speed. Connection with Internet is direct with connections up to 384kbps (bearing to constant technology xDSL). • High speeds help in the faster and more direct use of multimedia applications • Video-Streaming. Increased bandwidth allows transmission in real time, video with high definition sound • Advanced quality entertainment involving online real time gaming • Applications for localization in combination with GPS technology, providing maps, route navigators, traffic information etc. • Connections and services independent of location and environment. • VPN Mobile Office.
In the UMTS air interface we have the implementation of Wideband-CDMA (WCDMA) as the underlying standard. Some the key features of W-CDMA are listed here [32]: • Supports two basic modes of duplex: FDD (frequency division duplex) and TDD (time division duplex) • Employs coherent detection on uplink and downlink based on the use of pilot symbols • Inter-cell asynchronous operation • Variable mission: on a 10 ms frame basis • Multicode transmission • Adaptive power control based on SIR • Multiuser detection and smart antennas for increasing the capacity and coverage • Multiple types of handoffs between different cells including soft handoff, softer handoff and hard handoff
W-CDMA is based on the Direct Spread CDMA technique implenting plain CDMA in the FDD
UMTS
3GPP/UMTS was built having as basic purpose to offer users, transfer speeds up to 2Mbps, so they could have the ability to use applications that were not reachable due to limited capacity and transfer speed as quick access to internet, teleconference and many others. The standardisation of 3GPP for UMTS was focused mainly in three areas, i.e. services, air-interface and core network access.
Some of its most important advantages offered are [32]:
• Video-conferencing • High transfer data speed. Connection with Internet is direct with connections up to 384kbps (bearing to constant technology xDSL). • High speeds help in the faster and more direct use of multimedia applications • Video-Streaming. Increased bandwidth allows transmission in real time, video with high definition sound • Advanced quality entertainment involving online real time gaming • Applications for localization in combination with GPS technology, providing maps, route navigators, traffic information etc. • Connections and services independent of location and environment. • VPN Mobile Office.
In the UMTS air interface we have the implementation of Wideband-CDMA (WCDMA) as the underlying standard. Some the key features of W-CDMA are listed here [32]: • Supports two basic modes of duplex: FDD (frequency division duplex) and TDD (time division duplex) • Employs coherent detection on uplink and downlink based on the use of pilot symbols • Inter-cell asynchronous operation • Variable mission: on a 10 ms frame basis • Multicode transmission • Adaptive power control based on SIR • Multiuser detection and smart antennas for increasing the capacity and coverage • Multiple types of handoffs between different cells including soft handoff, softer handoff and hard handoff
W-CDMA is based on the Direct Spread CDMA technique implenting plain CDMA in the FDD