Universal Cellular Engineering - Technology


	Overview



	GSM



	GPRS



	EDGE



	TETRA



	UMTS/WCDMA



	CDMA

EDGE

EDGE
Enhance Data Rates for Global Evolution

Overview
EDGE is an expansion of the GSM/GPRS protocol to support higher data rates. This is accomplished by utilising 8-PSK (8-Phase Shift Keying) modulation technique and modulation coding schemes at the physical layer. This modulation provides an increase from 1 to 3 bits per symbol, thus improving the overall data throughput. The physical layer now consists of nine modulation coding schemes (MCS), which may be utilised for either the downlink (forward link) or the uplink (reverse link).

Scheme	Modulation	Data Rate (kbit/s)
CS-1	GMSK	8.8
CS-2	GMSK	11.2
CS-3	GMSK	14.8
CS-4	GMSK	17.6
CS-5	8-PSK	22.4
CS-6	8-PSK	29.6
CS-7	8-PSK	44.8
CS-8	8-PSK	54.4
CS-9	8-PSK	59.2

In addition to the modulation coding schemes, there are enhancements to the interleaving techniques, addressing and packet handling. The user may utilise more than 1 time slot per frame, thus increasing the overall data throughput.

To minimise network issues, EDGE utilises the same bandwidth and frequencies as the current GSM/GPRS protocol.

Specifications

Frequency Bands	Frequency Range
GSM 900 channels 0 – 124, 955 – 1023	876.2 to 914.8 MHz (uplink) 921.2 to 959.8 MHz (downlink)
GSM 1800 channels 512 – 885	1710.2 to 1784.8 MHz (uplink) 1805.2 to 1879.8 MHz (downlink)
GSM 1900 (Americas) channels 512 – 810	1850.2 to 1909.8 MHz (uplink) 1930.2 to 1989.8 MHz (downlink)
GSM 850 (Americas) channels 128 – 251	824.2 to 848.8 MHz (uplink) 869.2 to 893.8 MHz (downlink)
Channel spacing	200 kHz
Modulation	8-PSK (8-Phase Shift Keying) or GMSK (Gaussian Minimum Shift Keying)
Symbol rate	270,833 symbols/s
Bits per symbol	3
Access format	TDMA (time-division multiple access) TDD/FDD (time and frequency division duplex)
Number of channels per carrier	8 time slots per TDMA frame (4.615 ms)
Data	Up to 384 kbit/s
Power control	Yes, in 2-dB steps over a range of 30 dB