EDGE is an acronym for Enhanced Data rates for GSM evolution, it is a radio based high-speed mobile data standard. It allows data transmission speeds of 384 kbps to be achieved when all eight timeslots are used. In fact, EDGE was formerly called GSM384. This means a maximum bit rate of 48 kbps per timeslot. Even higher speeds may be available in good radio conditions.
EDGE was initially developed for mobile network operators who fail to win Universal Mobile Telephone System (UMTS) spectrum. EDGE gives incumbent GSM operators the opportunity to offer data services at speeds that are near to those available on UMTS networks.
EDGE can carry speeds up to 236.8 kbits/s for 4 timeslots (theoretical maximum is 473.6 kbits/s for 8 timeslots) in packet mode and will therefore meet the International Telecommunications Union’s requirement for a 3G network, and has been accepted by the ITU as part of the IMT-2000 family of 3G standards.
EDGE can also provide an evolutionary migration path from GPRS to UMTS by implementing now the changes in modulation that will be necessary for implementing UMTS later. The idea behind EDGE is to eke out even higher data rates on the current 200 kHz GSM radio carrier by changing the type of modulation used, whilst still working with current circuit (and packet) switches.
EDGE is the result of an effort between TDMA (Time Division Multiple Access) operators and vendors to develop a common set of 3G standards that support high-speed data. EDGE is a major component of UWCC-136, the 3G standards proposed by TDMA carriers. It is worth mentioning in this regard that in July 2000, the International Telecommunication Union has released a call for RFP for terrestrial component for IMT-2000. Out of 10 proposals, five were approved. The ITU recommendation ITU-R M.1457 specifies five types of 3G radio interfaces:
- IMT-2000 CDMA Direct Spread, also known as UTRA FDD including WCDMA in Japan, ARIB/ DoCoMo recommendation. UMTS is developed by 3GPP.
- IMT- 2000 CDMA Multi-Carrier, also known as Cdma2000 (3x) developed by 3Gpps. Imt-2000 CDMA includes 1X component, like cdma 2000 1X EV-Do
- IMT-2000 CDMA TDD, also known as UTRA TDD and TD-SCDMA. TD- SDMA is developed in China and supported by TD-SCDMA Forum
- IMT-2000 TDMA single carrier, also known as UMC-136 (Edge) supported by UWCC
- IMT-2000 DECT supported by DECT Forum
EDGE uses the same spectrum allocated for GSM900, GSM1800, GSM1900 operation. Instead of employing GMSK (Gaussian Minimum Shift Keying) EDGE uses 8 PSK (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 to increase the data rates that can be offered to users of the GSM spectrum, aligning the technology with 3G systems.
The GSMA takes the position that EDGE modulation techniques are a natural evolution of second generation GSM networks within the same spectrum band and GSM technology framework. Though the core network is the same and the frequencies used might be the same, however the air interface is different. And according to the ITU, which is the organization that sets telecom standards for worldwide use, the EDGE was approved in July 2000 as 3G standard.
Moreover the same association is one of the supporting organizations of the EDGE operators forum which classifies EDGE as a 3G technology (refer to http://www.gsacom.com/eof/index.php4)
Mobinil also refers to the fact that some countries have granted mobile operators the EDGE license for free. However this fact does not constitute any obligation on NTRA to follow in the same footsteps. For instance, Japan granted the 3G license for free whereas Germany and England granted the 3G license for 8 billion dollars. This proves once more that the decision maker in this regard is the sovereign authority handling the licensing, which in case of Egypt, is the NTRA.
Mobinil has made an agreement with the NTRA in 2004, according to which the NTRA approved for the import of equipment needed for the deployment of EDGE technology. The agreement however stipulates that Mobinil would not use the technology for commercial purpose unless upon approval of the NTRA.
It one of the main pillars of the NTRA mandate to protect free competition in the Egyptian market and in this regard, the NTRA is not against the deployment of EDGE, however it is totally against using it for free while other operators are paying for 3G services, which are almost similar to the EDGE services. It is also within the mandate of the NTRA to augment sanctions imposed on any service provider, which does not adhere to the free competition rules defined by the NTRA. Pursuant to Telecom Law 10/ 2003, the NTRA is in charge of the task of determining the limits which if exceeded will result in the occurrence of monopolistic practices in any of the fields regulated by the Law. (refer to http://www.ntra.gov.eg/uploads/law/law.doc)