Q&A: EDGE Evolution (EDGE II or Evolved EDGE)

What is EDGE?
What is EDGE Evolution?
How will these technology improvements for EDGE improve the user experience?
What is the expected latency for EDGE Evolution?
What techniques are employed to increase throughput rates?
When is the 3GPP specification effort for EDGE Evolution expected to be completed?
When can we expect to see EDGE Evolution-enabled products?
Will EDGE Evolution compete with HSPA or in the future with LTE?

What is EDGE?

Enhanced Data rates for GSM Evolution (EDGE) is a third-generation (3G), high-speed data technology, with theoretical network peak rates of 473 kbps and average throughput of 100-130 kbps. The average rates are fast enough to support a wide range of advanced data services, including fast Internet access and large file downloads. EDGE also supports push-to-talk (PTT) services.

EDGE is occasionally referred to as Enhanced GPRS (EGPRS) because it increases the capacity and data throughput of GPRS by three to four times. Like GPRS, EDGE is a packet-based service, which provides customers with a constant data connection. The ITU, which sets telecom standards for worldwide use, approved EDGE as a 3G standard in July 2000. In July 2003, the world’s first commercial EDGE network launched. As of December 2007, EDGE services are available from more than 263 networks in 131 countries with another 79 networks in planned, trialing or in construction stages.

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What is EDGE Evolution?

As its name implies, EDGE Evolution is an upgraded version of EDGE that completed standardization work in 2007 within Release 7 at 3GPP, an international standards body. EDGE Evolution is also referred to as EDGE II or Evolved EDGE by some industry sources. EDGE Evolution will boost data speeds by up to 300 percent and will significantly improve latency, coverage, and spectrum efficiency of existing GSM/EDGE equipment. This improved data performance in GSM will be as important as high-speed HSPA is today and LTE will be in tomorrow’s networks.

Compared to existing versions of EDGE, EDGE Evolution is expected to provide:

• A dramatic increase in data rates. In total, the peak rate per user will be as high as 1 Mbps for the downlink and 500 kbps for the uplink. The actual amount depends on the version used, but EDGE Evolution is expected to quadruple the throughput rates for EDGE with peak theoretical network speeds of 1184 kbps to 1894 kbps in type 1 or type 2 respectively for the downlink and and 473 to 947 kbps for the uplink.

• A 50% increase in spectral efficiency and capacity.
• Reduced latency for initial access and round-trip time, enabling better quality of service (QoS) for PTT and voice over IP (VoIP).
• Compatibility with existing frequency plans, thus facilitating rapid deployment in existing networks.
• A simple upgrade to existing GSM equipment allowing a more efficient use of scarce existing spectrum.
• A better seamless experience for subscribers as they roam from HSPA networks to EDGE networks.
• Compatibility with existing frequency plans, thus facilitating rapid deployment in existing networks.

For more information, see page 20 of the white paper Mobile Broadband: EDGE, HSPA and LTE.

Press Release: Ericsson EDGE to triple data speeds by 2009 (March 14, 2007)

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How will these technology improvements for EDGE improve the user experience?

EDGE Evolution is expected to improve the user-experienced performance across all services by:

• Reducing latency to improve the user experience of interactive services and also to enhance support for conversational services such as multimedia telephony
• Increasing peak and mean bit-rates, to improve best-effort services such as web browsing or music, picture and video up-/downloads
• Improving spectrum efficiency, which will particularly benefit operators where existing frequency spectrum is used to its maximum extent and traffic volume can be increased without compromising service performance or degrading perceived user quality
• Boosting service coverage; for example, through interference reduction or more robust services. Increased terminal sensitivity improves coverage in the noise limited scenario

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What is the expected latency for EDGE Evolution?

Latency is expected to be less than 80 milliseconds (ms), which is achieved by reducing the Transmission Time Interval (TTI) from 20 ms to 10 ms.

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What techniques are employed to increase throughput rates?

To improve the throughput rates for EDGE Evolution, Higher Symbol Rate and Higher Order Modulations are introduced for both downlink and uplink, while Downlink Dual Carrier transmission, MS Receive Diversity and Turbo Codes are introduced in downlink only. This improves the pear Rate per radio slot by 100%, to reach 120 kbps per time slot. In total, the peak rate per user will be as high as 1 Mbps for downlink and 500 kbps for uplink.

DL Coverage is improved by 3 dB with the introduction of MS Receive Diversity. Altogether the EDGE Evolution features will more than double the spectrum capacity.

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When is the 3GPP specification effort for EDGE Evolution expected to be completed?

The entire specification effort including conformance test specifications was completed in 2007. Companies are actively clarifying testing requirements.

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When can we expect to see EDGE Evolution-enabled products?

EDGE Evolution-enabled products are expected by 2009.

Following the recent 3GPP industry standardization, Ericsson is committed to launch EDGE evolution as a software upgrade of existing infrastructure by 2009.

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Will EDGE Evolution compete with HSPA or in the future with LTE?

The improved end-user performance of EDGE Evolution will stimulate mobile data usage and ensure service transparency between EDGE and HSPA as well as future LTE based services. The evolution of EDGE will also continue in Release 8 with the addition of Turbo Codes for uplink and possibly other enhancements as well.

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