Enhanced Data for Global Evolution (EDGE)

Enhanced data for global evolution is an evolved version of the global system for mobile (GSM) radio channel that uses new phase modulation and packet transmission to provide for advanced high-speed data services. The EDGE system uses 8 level phase shift keying (8PSK) to allow one symbol change to represent 3 bits of information. This is 3 times the amount of information that is transferred by a standard 2 level GMSK signal used by the first generation of GSM system. This results in a radio channel data transmission rate of 604.8 kbps and a net maximum delivered data transmission rate of approximately 474 kbps. The advanced packet transmission control system allows for constantly varying data transmission rates in either direction between mobile radios.

Figure 1.30 shows how a standard GSM radio channel is modified to use a new, more efficient modulation technology to create a high-speed packet data EDGE system. The EDGE system users either 8 level quadrature phase shift keying (QPSK) modulation or the standard GMSK modulation (used by 2nd generation GSM systems.) This allows EDGE technology to be merged on to existing GSM systems as standard GSM mobile telephones will ignore the EDGE modulated time slots that they cannot demodulate and decode.

Figure 1.30: EDGE System

Wideband Code Division Multiple Access (WCDMA)

Wideband code division multiple access is a 3rd generation mobile communication...