Saturday, October 4, 2008

Technology beyond 3G

From 2G, 2.5G, 3G (IMS, IP Multimedia Subsystem), 3.5G/HSDPA, to 4G

Computer Communications (IT), IP-based, WiFi (Data Comm.), VoIP

Data Services
  • GSM, Circuit Switching, 9.6 (*2), 12.4(*2, HSCSD)
  • GPRS, General Packet Radio Services, Packet Switching, 9.05 kbps/13.4 kbps (*1,2,3,4), speed denoted as *u*d
  • EDGE, 3 times of speed of GPRS by using 8-PSK instead of binary GMSK
  • 3G, 384kbps, up to 2 Mbps, uplink is 128 kbps
  • 3.5G HSDPA (High Speed Downlink Packet Access) 8-10 Mbps (R5), and 20 Mbps (R6) by MIMO, uplink is 384 kbps

OFDMA and WiMAX Technology (slides)

WiMAX vs. HSDPA
  • similar:Handover, Multimedia (<>
  • difference: physical, initial cost, TCO (Total Cost Ownership)
4G communication at 100 Mbit/s while moving, and 1 Gbit/s while stationary.

Pervasive networks
  • simultaneously connected to several wireless accesstechnologies (Wi-Fi, UMTS for example) and can seamlessly move between them (handover)
  • smart-radio aka cognitive radio technology to efficiently manage spectrum use and transmission power
  • mesh routing protocols
  • 4G may use OFDM , and also OFDMA.
  • packet switching only
In general, a generation is defined by the result of technology changes over a 10-15 year time frame. Thus, 4G would refer to whatever is deployed in the 2010-2015 period, assuming 3G deployment spans the 2000-2009 period.

See

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