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
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
See
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
See
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