Now, over halfway through 2003, UMTS is still largely a promise rather than a reality and EDGE is no longer perceived as a niche market. Although some people still claim publicly that EDGE will be peripheral to the European telecoms sector, their private opinions of the technology are more positive. Some EDGE handsets are already on the market and by the end of the year many more will be off the production line and into consumers' hands. Meanwhile, many of the base stations deployed since 1999 are already EDGE-ready.

In 2003, the first post-telecoms implosion year, the cellular industry has learned to distance itself from technology hype and focus on the consumer who actually pays the bills. Today's emerging GPRS networks are not being publicly branded by technology. Instead, brands such as "O2 Active", "T-Mobile T-Zones" and "Vodafone Live" are marketed as "mobile lifestyle" platforms to enhance consumer buy-in.

This network transparency bodes well for the industry because operators will not need to rebrand their networks as GPRS matures into EDGE and they introduce more data-centric services. This will decrease the cost of ownership per user and make EDGE a real revenue- and profit-boosting technology.

EDGE networks have several advantages over those based on GPRS in building for the future. EDGE compares favourably with GPRS by having better spectrum efficiency, throughputs and maximum data rates. Most current networks have been designed to support only the CS-1 and CS-2 GPRS coding schemes in terms of signal quality. EDGE MCS-5 has been specified to work at a 15 dB signal-to-interface ratio (SIR). This is close to current network CS-2 requirements so it means that moving to EDGE will not require network redeployment.

Surprisingly, some operators - T-Mobile, for example - have announced plans to deploy GPRS CS-3 and CS-4. They claim that this is to obtain higher data rates over GPRS and insist that they have no plans for EDGE deployment. The problem with this approach is that current networks have been designed for signal quality SIR over which CS-3 and CS-4 GPRS systems do not work well.

Unlike GPRS, where the standard specifications are rather tight in terms of possible implementation margins, EDGE solutions can be designed to perform well at much lower SIR values. They can provide data rates that are equivalent to CS-4, but with the current network deployment conditions. The higher data rates and throughputs are possible because of such EDGE features as incremental redundancy and link adaptation.

EDGE-enabled radio-frequency (RF) chipsets are available today from major vendors such as Analog Devices, Philips, Renesas, RF Micro Devices, Sony and Tropian. EDGE technologies utilize linear modulation rather than the constant-envelope Gaussian minimum-shift keying modulation of GSM and GPRS, so retaining the high efficiency exhibited by the nonlinear power amplifiers used in today's GSM/GPRS RF transmit path is a challenge. SiLabs, Texas Instruments and Skyworks are among the vendors working to enhance the transmission capabilities of EDGE-enabled chipsets.

The industry is also taking early steps to overcome EDGE interoperability issues. Such problems in the past caused the slower-than-expected adoption of GPRS. Chipset vendors such as BroadCom, Philips, Infineon and Siemens have recently announced that their products are in the advanced stages of interoperability testing.

Positive factors

The existence of intellectual property (IP) offerings in the market is also a positive factor for EDGE's success. IP companies like Comsys Communications are enabling quick-moving original design manufacturers (ODMs) to offer EDGE handsets in the near future to network operators. Several ODMs have identified EDGE as a stepping-stone to upgrading their market position from tier-3 to tier-2 supplier. They have recognized that EDGE is the near future of the wireless world and they intend to become the major drivers behind a proliferation of handsets that will enable operators to deploy EDGE networks without having to worry about first securing handsets from the major original equipment manufacturers.

Enhanced GPRS is on the edge of becoming a de facto industry standard for handsets. For newer networks, the average overhead for EDGE network deployment costs runs to approximately 10%. Although some operators are still reluctant to publicly admit that they are abandoning or postponing their UMTS plans, EDGE is now understood to be the best option as a 3G-service enabler for current networks.

Operators addressing EDGE are working hand in hand with the industry to define EDGE deployment features according to actual deployment requirements, in contrast to standard releases. Operators are concerned about complete functionality for EDGE and as such have created co-operative bodies, such as the EDGE Task Force of the GSA in the Americas and the Global Certification Forum in Europe, to ensure that EDGE can be adopted worldwide. After all, why be smitten again by telecoms hype - it is now time to share in the shaping of the future.

http://wireless.iop.org/articles/news/4/10/3/1