EDGE
Enhanced Data rates for Global Evolution
EDGE uses the same spectrum allocated for GSM900 , GSM1800 and GSM1900 operation. Instead of employing GMSK (Gaussian Minimum Shift Keying) EDGE uses 8PSK (8 Phase Shift Keying) producing a 3bit word for every change in carrier phase. This effectively triples the data rate offered by GSM. The use of EDGE enables GSM to increase the data rates that can be offered to users of the GSM spectrum. In release 7, Evolved EDGE (also termed EGPRS2) was introduced which offered higher data rates through mechanisms such as latency reduction, use of dual carriers in the downlink, higher order modulation techniques, increased symbol rate and receiver diversity in the mobile.