WHAT IS NGMN?

A brief Tutorial on NGMN Technology

Definition of Terms

"Next Generation Mobile Networks" (NGMN) is a distinct notation for the next generation of mobile wireless networks which will provide a groundbreaking technology evolution beyond today's 3rd generation mobile networks (3G) by the year 2010. The term "NGMN" is technology-agnostic and does not refer to one specific technology or technical standard, but to a range of technologies and standards with certain minimum characteristics,  see below.

The most prominent characteristics of NGMN are:

• The support of data rates up to 100 Mbit/s in the downlink (i.e. from the network to the end-user terminal) and up to 50 Mbit/s in the uplink (i.e. from the end-user terminal to the network) within a 20 MHz channel bandwidth; and
• A low end-to-end latency (round trip time for data packets) of less than 30 ms.

Please note that NGMN does not preclude the use of a channel bandwidth larger than 20 MHz in the future if frequency allocations allow this. Thus NGMN makes already provision towards "IMT-Advanced", which will support ultra-high downlink data rates up to 1 Gbit/s in a low mobility environment.

Motivation for NGMN

NGMN will push the frontiers of mobile broadband communications beyond the limits of currently deployed network technologies such as UMTS/3G/HSPA or CDMA-2000/EVDO. It will enable the competitive delivery of broadband wireless services with excellent data rates and cost performance ratios, thus greatly benefiting the end-customer. NGMN technologies will greatly improve the user experience of current and future mobile data and multimedia services and will make the broadband internet truly mobile.

In 2006, leading mobile operators have founded the world-wide "NGMN Alliance" in order to create a clear vision and industry consensus on the NGMN technology evolution beyond 3G across all regions of the world. The NGMN Alliance will greatly help to establish a viable and sustainable industry ecosystem for next generation mobile broadband networks and services. Further information on the NGMN Alliance can be found at MISSION & VISION.

Limitations of Current Technologies

Although the evolution of current 3G technologies is still progressing, these technologies suffer from a number of limitations which affect both, performance and costs:

• Peak data rates may achieve values in the 20 – 30 Mbit/s range (in the downlink) under optimum conditions, but hardly beyond this;
• The spectrum efficiency and thus average data throughput (capacity) per cell site is quite limited and not on par with latest technology advances;
• The channel bandwidth of typically 5 MHz does not always allow to get the best performance out of the multipath radio channel and, on the other hand, restricts the flexibility of network deployment in scarce spectrum bands;
• The end-to-end latency or round trip delay for data packets lies in the range of 200 ms or above which is insufficient for real-time services such as voice and gaming or applications with chatty protocols;
• The network architecture is deep with many node layers including both, circuit-switched and packet-switched network domains, which increases overall system complexity and costs;
• The network architecture is not optimised for IP (Internet Protocol) data traffic, efficient routing and always-on connection management;
• Radio network deployment, configuration, and optimisation is an elaborate and costly process.

Obviously, many of these limitations stem from the network architecture inherited from 2G cellular systems (e.g. GSM, IS-95/CDMA) and the CDMA radio technologies predominant in 3G.

NGMN will overcome these limitations by leveraging the latest advances in radio access technology for the specification of new high-performance air interfaces in the Radio Access Network (RAN) and by adopting a rigorous approach to a flat All-IP network architecture in the RAN and Core Network.

Characteristics of NGMN

Key characteristics and requirements of NGMN technologies and networks are:

• Peak data rates in the downlink beyond 100 Mbit/s (> 40 Mbit/s cell average);
• Peak data rates in the uplink beyond 50 Mbit/s;
• Spectrum efficiency and cell throughput (capacity) 3 – 5 times better than 3G/HSPA and CDMA-2000/EVDO;
• Low latencies (round-trip times) of 20 – 30 ms end-to-end;
• Flat All-IP network architecture, with open interfaces, legacy interworking, optimised routing and always-on support;
• Seamless mobility in indoor, pico/micro-cellular, metropolitan and wide-area deployment scenarios;
• Easy and cost-efficient network deployment leveraging advanced self-organisation, self-configuration and self-optimisation techniques;
• Flexible allocation of radio channel bandwidths in the range between 1.25 MHz and 20 MHz, utilising FDD and/or TDD duplex modes;
• Operation in a wide range of frequency bands between 400 MHz and 5 GHz taking into account the ITU spectrum identified for IMT-2000 and IMT-Advanced systems;
• High-performance, attractive and affordable end-user devices.

The NGMN Alliance has compiled and published a comprehensive set of recommendations, requirements and performance targets for next generation mobile networks in its White Paper on "Next Generations Mobile Networks Beyond HSPA & EVDO". With this White Paper, the NGMN Alliance provides a coherent view of what the operator community will require in the decade beyond 2010 to meet the end-user needs and create a virtuous cycle of investment, innovation, and adoption of mobile broadband services.

The NGMN Alliance does not intend to develop a new technology standard, but rather NGMN complements and supports the existing international standards development activities by providing consolidated operator requirements and recommendations, identifying critical gaps, and making dedicated contributions to the relevant standardisation committees. Main objective is to ensure that the relevant standards are completed in time and meet the NGMN requirements and recommendations as summarised in the NGMN White Paper.