Log in

ISM Article

LTE-Advanced Technologies for Wireless Devices

9 May, 2011 By: Dr. Satwant Kaur, HP imageSource

LTE-Advanced Technologies for Wireless Devices

LTE Advanced (LTE-A) is a mobile communication standard for radio
technologies for mobile broadband. LTE-A mobile broadband give us the bandwidth
needed to deliver tomorrow’s wireless networks. It will enable wireless devices
to “talk” to each other quicker, cheaper, and longer. This mobile broadband
standardization will be instrumental in unleashing the innovation of future
wireless sensor networks that will affect the way you and your customers conduct
your lives and business.

The acceptance of LTE -Advanced as a true 4G mobile broadband technology by
ITU-R is a leap toward realization of wireless connectivity for mobile devices (PDAs,
Smartphones, iPads, etc.). Mobile broad band’s improved bandwidth throughput and
latency will provide astonishing data transfer speeds, transforming our
voice-driven mobile phones into a wide range of data-driven information,
communications, and many entertainment applications. This will usher in an era
of wireless devices that will be a paradigm shift from voice-driven wireless
phones, and will make business and personal lives more efficient. You will be
able to run a business M2M (machine-to-machine) effectively and affordably, with
higher productivity yet less worker-centric.

Why LTE-A is Revolutionary

LTE-A’s revolutionary data performance will enable new applications and user
cases for mobile devices. This will lead to many (up to a thousand per person)
specialized devices with wireless access. Therefore, advanced wireless networks
and radio technologies are needed to support such connectivity. Thus bringing
the network closer to the user by providing high performance in the following
parameters of wireless connectivity; quite specifically, improved radio access
capacity and coverage, high peak data rates, low latency, reduced operating
costs, multi-antenna support, flexible bandwidth operations, and seamless
integration with existing systems. The performance and service parameters of LTE-A
are measures in speed, capacity, coverage, and latency.

Basically, the higher data transmission rates, higher bandwidth, higher
bandwidth efficiency and lower latency give mobile users the ability to utilize
high definition video and the video conferencing features on their mobile

Technologies Enabling High Performance

The technologies discussed below bring improved coverage, improved cell edge
coverage, and optimization of heterogeneous networks with advanced topology

TECH-1: Carrier Aggregation enables wide frequency bandwidth:

One of the new things that LTE-Advanced brings to the mobile devices is the
ability to extend transmission bandwidth by aggregation of bandwidth. With
Carrier Aggregation, many different component carriers can be aggregated and
used for transmission to and from a mobile device. The ability to aggregating
non-contiguous component carriers is very powerful, since now the fragmented
spectrum can be utilize to provide high data rate services similar to a wideband
even without a real single wideband spectrum allocation. Carrier aggregation
achieves extra-wide frequency bandwidth transmission by bundling multiple 20
MHz-wide bands (component carriers) for uplink and downlink.

TECH-2: Multi Antenna enables multiplexing during transmission

Another improvement that LTE-A brings to mobile devices is the Multiple
Antenna technology. Multiple antennas provide transmission multiplexing. This
expanded transmission dimension to a mobile device improves channel capacity &
spectral efficiency. MIMO (multiple-input and multiple-output) utilizes multiple
signal paths that may exist between a transmitter and receiver to improve the
data throughput. By using multiple antennae at the transmitter and receiver,
along with some complex digital signal processing, MIMO technology enables the
system to set up multiple data streams on the same channel, thereby increasing
the data capacity of a channel.

TECH-3: Co-ordination between base stations increases cell-edge throughput

LTE-A brings better transmission data rate between base station and mobile
devices that are located near cell edges by coordinating multiple base stations
that are close to the mobile device. LTE-A data rates are easy to maintain close
to the base station, but the cell edges are challenging. The signal becomes
faint as the distance from the base station increases, and the interference from
neighboring base stations increases as the mobile device gets closer to them.

CoMP (coordinated multi-point format) downlink transmission and uplink
reception allows coordination of the transmission or reception between one
mobile device and several base stations. This dynamic coordination between a
numbers of geographically separated base stations provides a mobile device, even
when they get to the edge of a cell, can get improved signal reception and
transmission. The beauty is that LTE-A’s coordinated multi-point format
technology, CoMP turns the inter-cell interference into a useful signal,
especially at the cell borders where performance may be degraded.

TECH-4: Orthogonal FDM eliminates interference in multi-path transmissions

Orthogonal Frequency Division Multiplex (OFDM) multi-path transmission
technology uses a large number of closely spaced carriers that are modulated
with low rate data. These signals are transmitted orthogonal to each another,
and thus, there is no mutual interference even when there are multi-path
transmissions in same channel.

TECH-5: Heterogeneous networks

Heterogeneous networks enable improvements in cell-edge user throughput and
coverage. Heterogeneous network provide interference coordination for overlaid
deployment of cells with different transmission power. Non-carrier aggregation
based solutions are important in order to enable efficient heterogeneous network
deployments when bandwidth availability is less, and mobile devices do not have
carrier aggregation capability.

In networks with unbalanced transmit power nodes sharing the same frequency,
coordination of control and data channel interference is important to maintain
the downlink and uplink cell coverage, and thus, good data channel performance.
Heterogeneous networks also allow adding many low power nodes like Picocells,
femtocells and relay nodes.

TECH-6: Relays

Relaying enables extension of both coverage and capacity, especially at cell
edges. The high data rates of LTE-A are a challenge to maintain at the cell edge
where signal levels are lower and interference levels are typically higher. LTE-A
relays enhance signal quality by receiving, demodulating, decoding, error
correcting the data, and then re-transmitting a new signal. The LTE-A provides
relaying of messages between the base station and the mobile devices through
multi-hop communication.

Applications in Wireless Connected Devices (WCD):

#1  Transportation: Connected Cars

Connected devices will enable Intelligent Roadways. Vehicle position,
velocity, and even intent can be used for traffic control and crash prevention.
Communicating devices will facilitate lane control and speed limit control.
Devices connected to our bank accounts will automatically deduct parking and
toll charges.

#2  Health Care: Network of Medical Devices

As costs to creating medical devices declines, even healthy humans will
choose to wear medical devices. Basic devices designed to monitor exercise,
food, and heart rate will help people to keep track of their habits and their
health. Devices to monitor vital signs can help save lives of at risk

#3  Office Management with Connected Devices

Office buildings will be monitored at a fine level with wireless sensors
designed to drastically reduce energy consumption. Wireless sensors will help
technicians find, diagnose, and repair air, electrical, and plumbing systems of
buildings. Security sensors will protect buildings more thoroughly. Sensors on
products, machines, and people, including service technicians, will make
inter-office transportation, delivery & service call effectiveness more
efficient and affordable.

In summary, LTE-Advanced brings to mobile devices the worldwide functionality
of the device, compatibility of services between different providers,
inter-working with other radio access systems that make up the radio network and
enhanced peak data rates to support advanced services and applications. Thus
unleashing a whirlwind of B2B applications that will transform the way
businesses operate.  

Dr. Satwant Kaur is a Management & Technology Consultant; book author of
“Transitioning Embedded Systems to Intelligent Environments,” and was a platform
strategist in the Intel Architecture Group at Intel, CTO of the Emerging
Technologies Group at TIBCO Software, Director of Development at Symantec &
Chief Technology Architect of Quest Software. She holds a Doctorate in Mobile
Internet Protocols sponsored by Nokia Research Center. At


WebinarCase Studies and White PapersSand Exchange Blog

imageSource Magazine Quick Links
Upcoming Events
ITEX Expo & Conference
©2015 Questex, LLC. All rights reserved
Reproduction in whole or part is prohibited
Please send any technical comments or questions to our webmaster