DL - 4G Americas

One of key elements of the LTE/SAE network is the new enhanced base station, or Evolved NodeB
(eNodeB), per 3GPP Rel-8 standards. This enhanced BTS provides the LTE interface and performs radio
resource management for the evolved access system. At CTIA Wireless 2009 in April, eNodeB
demonstrations were provided by several vendors. The eNodeB base stations offer a zero footprint LTE
solution, address the full scope of wireless carriers’ deployment needs and provide an advanced LTE
RAN solution to meet size and deployment cost criteria. The flexible eNodeB LTE base stations will
support FDD or TDD and will be available in a range of frequencies from 700 MHz to 2.6 GHz with
bandwidths from 1.4 MHz to 20 MHz.
The first Rel-8 compliant LTE eNodeB ready for large-scale commercial deployment was launched in July
2009, and is capable of supporting a peak theoretical rate of up to 150 Mbps on the downlink. Regulatory
authorities around the world have moved forward with certification of LTE equipment in various bands.
By November 2009, LTE base stations (eNodeBs) were commercially available from Alcatel-Lucent,
Ericsson, Huawei, Motorola, Nokia Siemens Networks and Fujitsu. Several other leading vendors made
announcements in 2010.
The eNodeB features enhanced coverage and capacity for improved performance, superior power
efficiency for reduced energy consumption, lower total cost of ownership, and advanced Self-Organizing
Network (SON) implementation to help operators build and operate their LTE networks at a lower cost.
SON aims to leapfrog to a higher level of automated operation in mobile networks and is part of the move
to LTE in Rel-8. Benefits of SON include its ability to boost network quality and cut OPEX. Traffic patterns
in cellular networks are changing quickly with mobile data closing in on voice services; therefore, an
intelligent network with the ability to quickly and autonomously optimize itself could sustain both network
quality and a satisfying user experience. In this context, the term Self-Organizing Network is generally
taken to mean a cellular network in which the tasks of configuring, operating, and optimizing are largely
automated. Radio access elements account for a large share of cellular networks’ installation,
deployment, and maintenance costs. This is why efforts to introduce SON focus on the network’s radio
access assets first. A 2006 decision by the Next Generation Mobile Networks (NGMN) alliance was
instrumental in driving development of SON. NGMN singled out SON as a key design principle for the
next-generation mobile network, and published a specifications paper in 2008. Hence, SON was often
associated with LTE technology. And as a consequence, while drafting LTE specifications, 3GPP
introduced SON in Rel-8. Subsequent 3GPP releases will cover further SON specifications, starting with
auto-configuration functions.
In October 2009, T-Mobile completed testing on the world’s first LTE Self-Organizing Network (SON) in
Innsbruck, Austria. Also in October, a manufacturer announced a revolutionary base station
commissioning process called “SON Plug and Play.”
Depending on regulatory aspects in different geographical areas, radio spectrum for mobile
communication is available in different frequency bands, in different sizes and comes as both paired and
unpaired bands. Consequently, when the work on LTE started late 2004 with 3GPP setting the
requirements on what the standard should achieve, spectrum flexibility was established as one of the
main requirements, which included the possibility to operate in different spectrum allocations ranging from
1.4 MHz up to 20 MHz, as well as the possibility to exploit both paired and unpaired spectrum. In
essence, this meant that the same solutions should be used for FDD and TDD whenever possible in
order to provide a larger economy of scale benefit to both LTE FDD and LTE TDD.
LTE operating in both FDD and TDD modes on the same base station was first demonstrated in January
2008. By using the same platform for both paired and unpaired spectrum, LTE provides large economies
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