2. 3G Journey
Radio Department
Confidentiality level-C2
3G Journey
Radio Department
1. LTE Overview.
2. LTE Key Features
3. LTE Radio Access Network.
4.LTE services and Markets
5.LTE devices availability
3. 3G Journey
Radio Department
Confidentiality level-C2
LTE Overview
What is LTE ?
>Long Term Evolution is the global standard for the fourth
generation of mobile networks (4G) supported by all
major players in the industry, which designed to meet
the high speed data and multimedia transport needs of
operator.
3
4. 3G Journey
Radio Department
Confidentiality level-C2
LTE Overview
Why LTE ?
> 1. Performance and Capacity – One of the requirements of LTE is
to provide downlink peak rates of at least 100Mbps and uplink peak
rate of at least 50 Mbps. However , the technology allows for
speeds more than 300Mbps.
> 2. Latency – The user plane latency achieved in LTE is less than in
existing 3G technologies providing a direct service advantage for
highly immersive and interactive application environments.
> 3. Simplicity and Network Cost – LTE supports flexible carrier
bandwidths, from 1.4MHz up to 20MHz. LTE also supports
frequency division duplex (FDD) and time division duplex (TDD) in
addition to simple network structure.
> 4. Applications – LTE are HD Video Streaming, video
conferencing, Remote Education, 3D Advertising and Virtual e-
commerce, 3D Gaming, M2M communication (specially in health
care) and public safety applications (data tsunami)
4
6. 3G Journey
Radio Department
Confidentiality level-C2
LTE Overview
Why LTE ? (cont.)
>Initial findings
– The 2600MHz band remains the most popular globally for initial launches of
LTE, favored by almost half of operators.
– The bands around 700MHz to 800MHz are expected to be the next-most-
widely used for initial launches.
– Up to eleven bands are expected to be used in any single region (the region
with the largest number of bands is Asia-Pacific)
– Band pairings will be a feature of many markets, with a lower band for
coverage in rural and less populated areas, and a higher band for capacity in
dense urban and urban areas, and in hotspots
– There is evidence of growing support among operators for the 1800MHz
band, which is regarded as providing an ideal combination of coverage and
capacity
– Support for TD-LTE is growing outside major markets such as China
– All regions will see deployments in multiple bands
6
7. 3G Journey
Radio Department
Confidentiality level-C2
LTE Overview
Why LTE ?
>LTE spectrum – key concerns
– The availability of spectrum is a major concern for operators as
they formulate their LTE-deployment plans. There is widespread
uncertainty among regulators, operators and vendors as to which
bands will become available and when
– Operators that are eager to deploy LTE are having to make
choices based on currently available spectrum. Those planning to
deploy in the future have to formulate their plans against a
background of uncertainty about spectrum availability and
timelines
– Spectrum fragmentation poses a real threat that could slow the
deployment of LTE and so delay realizing the full benefits of the
technology, not least in terms of efforts to create economies of
scale for devices
7
9. 3G Journey
Radio Department
Confidentiality level-C2
2
LTE Overview
LTE Standards
LTE “Radio Evolution”: Long Term Evolution
SAE“Core Evolution” : System Architecture
Evolution.
As UMTS, LTE standardization is led by 3G
PP
LTE is considered as evolution for UMTS and
describes as Release 8
18. 3G Journey
Radio Department
Confidentiality level-C2
LTE Architecture
In 3G mobile systems the radio access part is mainly composed of 2 elements: the
NodeBs handle radio access in physical and network layers; the RNCs controls several
NodeBs and is responsible for mobility management.
For the evolution in the radio access network, one of the important changes in E-UTRAN
for LTE is the flat architecture where more functions are added to the base stations
namely eNodeB instead of NodeB.
In LTE, each eNodeB is connected to the Evolved Packet Core (EPC) by the S1
interface. On the user plane the S1 interface terminates the Serving Gateway (S-GW);
on the control plane the S1 interface terminates the Mobility Management Entity (MME).
The MME handles control plane signalling, especially for mobility management and idle
mode signalling. The S-GW processes the user plane data.
The eNodeBs are also interconnected with each other by the X2 interface, which is
mainly used for inter-eNodeB handover purpose.
18
20. 3G Journey
Radio Department
Confidentiality level-C2
LTE Deployment Status :
> There are about 39 LTE networks live
worldwide in November 2011, more
than half of which were launched in
2011.
> Within the next two to three years, it is
expected to have about 170 operators,
in 60 different countries, that are
running trials or have expressed interest
in LTE as they await spectrum auctions.
• In case of Arab region; it is expected that LTE would reach about 6% of all mobile
subscriptions by 2014.
Source: AMEinfo.com
21. 3G Journey
Radio Department
Confidentiality level-C2
LTE Deployment Status : (cont.)
Forecasting from "TeleGeography" suggests
that there will be more than 400 million LTE
mobile subscribers by the end of 2016.
Currently, the number of subscribers is
about nine million.
The bulk of the growth over the next five years
will be mainly in Asia, which will account for
almost half of LTE subscribers in 2016.
25. 3G Journey
Radio Department
Confidentiality level-C2
LTE Device Availability
>LTE device status as of 1H11
– Majority of the services are accessible via portable routers, USB
dongles, Wi-Fi routers and connected net-books; only two are using
smart-phones and tablet devices
– 71 mobile device models announced so far: 52% support the
700MHz band - 25% support the 2600MHz band - 17% support the
1800MHz band - 14% support the 800MHz band - 11% support the
2100MHz band - 11% support AWS - 4% support the 900MHz band
– 57% of current LTE mobile devices are single LTE band, 17% are
dual LTE band and only 26% are LTE tri-bands or more
27. 3G Journey
Radio Department
Confidentiality level-C2
MIMO Antennas
R
X
TX
Tx1 ≠
Tx2
Tx1 =
Tx2
Tx1 ≠
Tx2
Tx
1
Tx
2
Rx1
Rx2
The benefits of a MIMO system depend on independence (low cross-correlation) of the
transmit paths.
Spatial diversity or polarization diversity (±45o X-poles) are the most commonly used
antenna
configurations.
28. 3G Journey
Radio Department
Confidentiality level-C2
MIMO Antennas (cont.)
Single X-pole Antenna
This is a typical MIMO deployment scenario: a single antenna package with dual
antennas with ±45º
antenna-element-array to provide both receive and transmit diversity.
This configuration is currently the most common deployment scenario (without a
second transmit chain)
and can be very easily transformed into 2 x 2 MIMO with few physical changes
(inclusion of a second transmit chain is all that is necessary).
The disadvantages of this configuration are the need for an additional duplexer for
the second port and the associated loss.
Two X-pole Antennas with Spatial Gap
In this configuration, two dual-polar antennas are physically separated
(distance) with a single branch of each antenna exclusively carrying a
transmit path while the other branch carries the receive path.
This configuration eliminates any losses associated with the required
duplexers for each transmit and receive chain. While there is a cost for
the additional cabling and the associated ancillary equipment, an
advantage of this configuration is it can also be utilized for 4 x 2 MIMO
deployment.
A minimum horizontal separation is recommended between the
two antennas to ensure minimum correlation.
29. 3G Journey
Radio Department
Confidentiality level-C2
MIMO Antennas (cont.)
Polarization Diversity and MIMO Performance in Rural environment
In a rural environment:
• Limited MIMO gain is expected, due to the absence of scattering.
• Near cell condition where high SNR is detected represents only a fraction of the cell.
Given these limitations, space diversity is recommended in a rural environment due to expected higher
diversity gain.
30. 3G Journey
Radio Department
Confidentiality level-C2
TDD Vs. FDD
> Frequency-Division Duplex (FDD) means that the transmitter and receiver
operate at different carrier frequencies. The term is frequently used in ham
radio operation, where an operator is attempting to contact a repeater station.
The station must be able to send and receive a transmission at the same time,
and does so by slightly altering the frequency at which it sends and receives.
This mode of operation is referred to as duplex mode or offset mode
> Time-Division Duplex (TDD) : separate outward and return signals. It
emulates full duplex communication over a half duplex communication link
