International Journal of Engineering Trends and Technology (IJETT) - Volume4Issue4- April 2013
A Review On Improving Technologies In
Wireless Communications
Parasa Sri Sai Chaitanya#1, Suresh Angadi*2
#
*
Final Year B.Tech, Dept. Of ECE, K L University, Vaddeswaram, Guntur, AP, India.
Asst.professor in ECE Dept., K L University, Vaddeswaram, Guntur, AP, India.
Abstract— This paper presents an overview on rapid growing
wireless technologies. Innovation and application in wireless
technologies has been accelerating over the past years in a wide
range of areas. The paper gives the idea of these technologies
indicating the features, challenges and real time application.
Keywords—Wireless, Zigbee, Bluetooth, Wi-Fi.
I. INTRODUCTION
Innovation and application in wireless technologies has
been accelerating over the past years in a wide range of areas.
There are various wireless technologies that are rapidly being
applied in various applications and are very much useful in
automation. Automation of various services can be achieved
through wireless communication. This paper gives idea of
these technologies like Wi-Fi, Zigbee, Bluetooth.
II. WIRELESS COMMUNICATION
Wireless communication is the transfer of information
between two or more points that are not connected by an
electrical conductor. The most common wireless technologies
use electromagnetic wireless telecommunications, such
as radio. With radio waves distances can be short, such as a
few metres for television remote control, or as far as
thousands or even millions of kilometres for deep-space radio
communications. It encompasses various types of fixed,
mobile, and portable applications, including two way radios,
cellular telephones and wireless networking. there are many
kinds of wireless systems other than cellular. First there are
the broadcast systems such as AM radio, FM radio, TV and
paging systems. All of these are similar to the downlink part
of cellular networks, although the data rates, the sizes of the
areas covered by each broadcasting node and the frequency
ranges are very different. Next, there are wireless LANs (local
area networks). These are designed for much higher data rates
than cellular systems, but otherwise are similar to a single cell
of a cellular system. These are designed to connect laptops
and other portable devices in the local area network within an
office building or similar environment. There are smallerscale standards like Bluetooth or a more recent one based on
ultra-wideband (UWB) communication whose purpose is to
reduce cabling in an office and simplify transfers between
office and hand-held devices. And there are also technologies
like GSM and Zigbee for longer distance communication.
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III. BLUETOOTH
Bluetooth (IEEE 802.15.1)[1, 5] currently provides network
speeds of up to 3 Mbps. Bluetooth operates in the range of
2400–2483.5 MHz (including guard bands). This is in the
globally unlicensed Industrial, Scientific and Medical (ISM)
2.4 GHz short-range radio frequency band. Bluetooth uses a
radio technology called frequency-hopping spread spectrum.
The transmitted data is divided into packets and each packet is
transmitted on one of the 79 designated Bluetooth channels.
Each channel has a bandwidth of 1 MHz. The first channel
starts at 2402 MHz and continues up to 2480 MHz in 1 MHz
steps. It usually performs 1600 hops per second,
with Adaptive Frequency-Hopping (AFH) enabled. Bluetooth
is a packet-based protocol with a master-slave structure. One
master may communicate with up to 7 slaves in a piconet; all
devices share the master's clock. Packet exchange is based on
the basic clock, defined by the master, which ticks at 312.5 µs
intervals. Two clock ticks make up a slot of 625 µs; two slots
make up a slot pair of 1250 µs. In the simple case of singleslot packets the master transmits in even slots and receives in
odd slots; the slave, conversely, receives in even slots and
transmits in odd slots. Packets may be 1, 3 or 5 slots long but
in all cases the master transmits will begin in even slots and
the slave transmits in odd slots.
Bluetooth provides a secure way to connect and exchange
information between devices such as faxes, mobile phones,
telephones, laptops, personal computers, printers, Global
Positioning
System (GPS)
receivers, digital
cameras,
and video game consoles. It was principally designed as a
low-bandwidth technology.
IV. ZIGBEE
ZigBee (IEEE 802.15.4) [8, 5] is a new low-cost and lowpower wireless PAN standard, intended to meet the needs of
sensors and control devices. Typical ZigBee applications do
not require high bandwidth, but do impose severe
requirements on latency and energy consumption. A wireless
sensor network,
which
combines
computer
and
communication technology with the technology of sensor
network, is considered to be one of the emerging technology
that will affect the future of human civilization. This network
is composed of numerous and ubiquitous micro sensor nodes
which have the ability to communicate and calculate. These
nodes can monitor, sense and collect information of different
environments and various monitoring objects cooperatively.
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International Journal of Engineering Trends and Technology (IJETT) - Volume4Issue4- April 2013
ZigBee is a low-rate, low-cost and low-power kind of short
range wireless network communication protocol. Compared
with other wireless technologies, ZigBee has unique
advantages of safe and reliable data transmission, an easy and
flexible network configuration, low equipment costs and longlasting batteries. Thus, it has great development potential and
a promising market application in the field of industrial
control. By applying a wireless sensor network based on
ZigBee to a train fire detection system, information such as
temperature and humidity at any place of the train is covered
by the network could easily be collected, dealt with and
analyzed at any time. In addition, the system can be extended
significantly, the cost of equipment maintenance could be
reduced and the whole system could be optimized.
ZigBee builds upon the physical layer and medium access
control defined in IEEE standard 802.15.4 (2003 version) for
low-rate WPANs. The specification goes on to complete the
standard by adding four main components: network layer,
application layer, ZigBee device objects (ZDOs) and
manufacturer-defined application objects which allow for
customization and favor total integration. Besides adding two
high-level network layers to the underlying structure, the most
significant improvement is the introduction of ZDOs. These
are responsible for a number of tasks, which include keeping
of device roles, management of requests to join a network,
device discovery and security. ZigBee is not intended to
support powerline networking but to interface with it at least
for smart metering and smart appliance purposes. Because
ZigBee nodes can go from sleep to active mode in 30 ms or
less, the latency can be low and devices can be responsive,
particularly compared to Bluetooth wake-up delays, which are
typically around three seconds. Because ZigBee nodes can
sleep most of the time, average power consumption can be
low, resulting in long battery life. A Bluetooth SMART device
can when advertising is pushed to maximum connect,
exchange data and disconnect in 3 ms. This significantly
enhances the experiences for HID devices.
V. UWB
UWB (IEEE 802.15.3a), or Ultra Wide Band [7, 5], is a
potential competitor to the IEEE 802.11 standards. However,
UWB is more intended for home multimedia networking,
whereas 802.11 networks targets data networking, not only in
home environments, but also in public and enterprise
environments. Looking at the wireless PAN market, currently
dominated by Bluetooth, UWB offers a solution with much
higher bandwidth. Network speeds offered by UWB are in
theory several hundreds of Mbps, although initially speeds of
up to 100 Mbps are more likely. UWB uses very low-powered,
short-pulse radio signals to transfer data over a wide spectrum
of frequencies. This broad spectrum of frequencies makes it
tolerant to disturbances, making it attractive for a noisy
automotive environment.
A significant difference between conventional radio
transmissions and UWB is that conventional systems transmit
information by varying the power level, frequency, and/or
phase of a sinusoidal wave. UWB transmissions transmit
information by generating radio energy at specific time
intervals and occupying a large bandwidth, thus
enabling pulse-position or time modulation. The information
can also be modulated on UWB signals (pulses) by encoding
the polarity of the pulse, its amplitude and/or by using
orthogonal pulses. UWB pulses can be sent sporadically at
relatively low pulse rates to support time or position
modulation, but can also be sent at rates up to the inverse of
the UWB pulse bandwidth. Pulse-UWB systems have been
demonstrated at channel pulse rates in excess of 1.3
gigapulses per second using a continuous stream of UWB
pulses (Continuous Pulse UWB or C-UWB), supporting
forward error correction encoded data rates in excess of 675
Mbit/s.
VI. WI-FI
Wi-Fi (wireless fidelity) is the general term for any typeof
IEEE 802.11 network [4]. Examples of 802.11 networks are
the 802.11a (up to 54 Mbps), 802.11b (up to 11 Mbps), and
802.11g (up to 54 Mbps). These networks are used as WLANs.
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International Journal of Engineering Trends and Technology (IJETT) - Volume4Issue4- April 2013
The three 802.11 standards differ for the offered bandwidth,
coverage, security support and, therefore, the kind of
applications supported. 802.11a is better suited for multimedia
voice, video and large-image applications in densely
populated user environments. However, it provides relatively
shorter range than 802.11b, which consequently requires
fewer access points for coverage of large areas. The 802.11g
standard is compatible with and may replace 802.11b, partly
due to its higher bandwidth and improved security.
A standard Wi-Fi modem looks as shown.
FIG. Wi-Fi NETWORK
VII.
CONCLUSION
This paper has presented existing and upcoming wireless
networking technologies, and identified basic wireless
applications relying on these technologies. There are several
open issues to be addressed. First, which wireless applications
rely on real-time systems and how existing research on
wireless real-time communications can provide support for
these applications. Finally, it should be discussed how these
wireless technologies should be integrated in the existing
communications architecture comprising several network
protocols, e.g., CAN, LIN and MOST, and if such an
architecture should be extended with a wireless infrastructure.
REFERENCES
FIG. Wi-Fi modem
A wireless access point (WAP) connects a group of wireless
devices to an adjacent wired LAN. An access point resembles
a network hub, relaying data between connected wireless
devices in addition to a (usually) single connected wired
device, most often an Ethernet hub or switch, allowing
wireless devices to communicate with other wired devices.
Increasingly in the last few years (particularly as of 2007),
embedded Wi-Fi modules have become available that
incorporate a real-time operating system and provide a simple
means of wirelessly enabling any device which has and
communicates via a serial port. This allows the design of
simple monitoring devices. An example is a portable ECG
device monitoring a patient at home. This Wi-Fi-enabled
device can communicate via the Internet.
[1] Bluetooth Special Interest Group (SIG). Bluetooth Core
Specification. Version 2.0 + EDR, November 2004.
[2] Car2Car Communication Consortium.
http://www.car-2-car.org/.
[3] FlexRay Communications System - Protocol Specification.
Version 2.0, June 2004.
[4] IEEE 802.11, The Working Group Setting the Standards for
Wireless LANs. http://www.ieee802.org/11/.
[5] IEEE 802.15, Working Group for Wireless Personal Area
Networks (WPANs). http://www.ieee802.org/15/.
[6] NOW: Network on Wheels. http://www.network-onwheels..
[7] Ultrawidebandplanet.com.
http://www.ultrawidebandplanet.com/.
[8] ZigBee Alliance. http://www.zigbee.org/.
BIOGRAPHIES
Parasa Sri Sai Chaitanya#1 was born in 1991
in Krishna District. He is currently pursing
B.Tech (Electronics and Communication
Engineering) from K L University. He is
interested in Communication systems.
Email:saiparasa10@gmail.com
Suresh Angadi*2 is presently working as a
Asst.Professor in K L University. He
received his B.Tech degree in electronics
and communication in G.V.P College of
Engineering, vizag, 2007 and completed
M.Tech in Maulana Azad National Institute
of Technology (NIT BHOPAL) in 2009,
Bhopal. He is interested in Communication
Systems.
Email: suresh.a@kluniversity.in
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