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GUIDE HOD principal
( mr. Dirange.M.H.) ( mr. Dirange.M.H.) (mr.Khandare.P.P)
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ACKNOWLEDGMENT
WITH THE BLESSING OF SHRIRAM I COMPLITE THE HOLE WORK. I
HEARTLYTHANKSTOMYTEACHERSWHOHASSUPPORTMETHROUGHOUTMY
REPORT.I ALSO THANKS FULL TO MY DEPT.ELECTRONICS &
TELECOMMUNICATION. HAS PRIVIDED THE SUPPORT.I HAVE NEEDE TO
PRODUCESANDCOMPLETEMYSEMINARREPORTANDITHANKSTOMYFRIENDS
AND MY PARENTS BECAUSE THEY SUPPORTING TO ME THRGOUH OUT MY
REPORTTHROUGHVARIOUSMETHOD.
ARNIKAR ABHIJEET ASHOK
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WIRELESS COMMUNICATION
Arnikar Abhijit Ashok
T.Y.E.&T.C.
S.I.E.T.(Poly.), Paniv.
E-mail: - [email protected]
ABSTRACT
As the evolution of science of leaded towards communication system it
was in wired system for near about century. Wireless services have migrated from the
conventional voice-centric services to data-centric services. The circuit switched communication
network is now being replaced by all-IP packet-switched network. A complete wireless system
involves many different areas. It had overcome all the drawbacks that were observed in wired
system. Wireless system can communicate over distance of thousands of miles.
The wireless communication may be digital or analog. Digital wireless
communication means communication taking place due to digits and logical operations, whereas
in analog system it takes place due to square, pulse or sinusoidal wave modulation. It needs 1transmitter, 1 receiver with free media. It uses modulating system such as frequency modulation,
phase modulation, amplitude modulation. It uses frequency domains or spectrums for the
communication process. It may be simplex, half duplex or full duplex. As a result of technical
evolution the most common example of wireless communication is MOBILE PHONE.
KEYWORDS: -
Transmitter, Receiver, Media, Digital, Analog, Modulation.
mailto:[email protected]:[email protected]8/4/2019 Wire Less Communication
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Index
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Wireless Communication
1.Introduction
Fig: Radio of earlier days
Wireless communication
Wireless communication is the transfer of information over a distance without the use
of electrical conductors or "wires". The distances involved may be short (a few meters as in
television remote control) or long (thousands or millions of kilometers for radio
communications). Wireless communication is generally considered to be a branch of
telecommunications.
Situations Justifying Use of Wireless Technology
Wireless networking (i.e. the various types of unlicensed 2.4 GHz Wi-Fi devices) is
used to meet many needs. Perhaps the most common use is to connect laptop users who travel
from location to location. Another common use is for mobile networks that connect via satellite.
http://en.wikipedia.org/wiki/Wireless_networkinghttp://en.wikipedia.org/wiki/Wireless_networking8/4/2019 Wire Less Communication
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A wireless transmission method is a logical choice to network a LAN segment that must
frequently change locations. The following situations justify the use of wireless technology:
To span a distance beyond the capabilities of typical cabling, To provide a backup communications link in case of normal network failure, To link portable or temporary workstations, To overcome situations where normal cabling is difficult or financially impractical, or To remotely connect mobile users or networks.
Modes of Wireless Communication
radio frequency communication, microwave communication, for example long-range line-of-sight via highly directional
antennas, or short-range communication, or
infrared (IR) short-range communication, for example from remote controls or viaInfrared Data Association (IrDA).
Applications may involve point-to-point communication, point-to-multipoint communication,
broadcasting, cellular networks and other wireless networks.
This chapter surveys the economics literature on wireless communications.
Wireless communications and the economic goods and services that utilise it have some special
characteristics that have motivated specialised studies. First, wireless communications relies on a
scarce resource namely, radio spectrum the property rights for which were traditionally
vested with the state. In order to foster the development of wireless communications (including
telephony and broadcasting) those assets were privatised. Second, use of spectrum for wireless
communications required the development of key complementary technologies; especially those
that allowed higher frequencies to be utilised more efficiently. Finally, because of its special
nature, the efficient use of spectrum required the coordinated development of standards. Those
standards in turn played a critical role in the diffusion of technologies that relied on spectrum
use.
http://en.wikipedia.org/wiki/Radiohttp://en.wikipedia.org/wiki/Microwavehttp://en.wikipedia.org/wiki/Infraredhttp://en.wikipedia.org/wiki/Remote_controlhttp://en.wikipedia.org/wiki/Infrared_Data_Associationhttp://en.wikipedia.org/wiki/Point-to-point_(telecommunications)http://en.wikipedia.org/wiki/Point-to-multipoint_communicationhttp://en.wikipedia.org/wiki/Broadcastinghttp://en.wikipedia.org/wiki/Cellular_networkhttp://en.wikipedia.org/wiki/Wireless_networkhttp://en.wikipedia.org/wiki/Wireless_networkhttp://en.wikipedia.org/wiki/Cellular_networkhttp://en.wikipedia.org/wiki/Broadcastinghttp://en.wikipedia.org/wiki/Point-to-multipoint_communicationhttp://en.wikipedia.org/wiki/Point-to-point_(telecommunications)http://en.wikipedia.org/wiki/Infrared_Data_Associationhttp://en.wikipedia.org/wiki/Remote_controlhttp://en.wikipedia.org/wiki/Infraredhttp://en.wikipedia.org/wiki/Microwavehttp://en.wikipedia.org/wiki/Radio8/4/2019 Wire Less Communication
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In large part our chapter focuses on wireless telephony rather than broadcasting and
other uses of spectrum (e.g., telemetry and biomedical services). Specifically, the economics
literature on that industry has focused on factors driving the diffusion of wireless
telecommunication technologies and on the nature of network pricing regulation and competition
in the industry. By focusing on the economic literature, this chapter complements other surveys
in this Handbook. Hausman (2002) focuses on technological and policy developments in mobile
telephony rather than economic research per se. Cramton (2002) provides a survey of the theory
and practice of spectrum auctions used for privatisation. Armstrong (2002a) and Noam (2002)
consider general issues regarding network interconnection and access pricing while Woroch
(2002) investigates the potential for wireless technologies as a substitute for local fixed line
telephony. Finally, Liebowitz and Margolis (2002) provide a general survey of the economics
literature on network effects. In contrast, we focus here solely on the economic literature on the
mobile telephony industry.
The outline for this chapter is as follows. The next section provides background information
regarding the adoption of wireless communication technologies. Section 3 then considers the
economic issues associated with mobile telephony including spectrum allocation and standards.
Section 4 surveys recent economic studies of the diffusion of mobile telephony. Finally, section
5 reviews issues of regulation and competition; in particular, the need for and principles behind
access pricing for mobile phone networks.
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2.History: -
In 1895, Guglielmo Marconi opened the way for modern wireless communications
by transmitting the three-dot Morse code for the letter S over a distance of three kilometers
using electromagnetic waves. From this beginning, wireless communications has developed into
a key element of modern society. From satellite transmission, radio and television broadcasting
to the now ubiquitous mobile telephone, wireless communications has revolutionized the way
societies function.
. Wireless telegraphy was first used by the British military in South Africa in 1900 during the
Anglo-Boer war. The British navy used equipment supplied by Marconi to communicate
between ships in Delagoa Bay. Shipping was a major early client for wireless telegraphy and
wireless was standard for shipping by the time the Titanic issued its radio distress calls in 1912.
2.1Photophone
The world's first, wireless telephone conversation occurred in 1880, when
Alexander Graham Bell and Charles Sumner Tainter invented and patented the photophone, a
telephone that conducted audio conversations wirelessly over modulated light beams (which are
narrow projections ofelectromagnetic waves). In that distant era when utilities did not yet exist
to provide electricity, and lasers had not even been conceived of in science fiction, there were no
practical applications for their invention, which was highly limited by the availability of both
sunlight and good weather. Similar to free space optical communication, the photophone also
required a clear line of sight between its transmitter and its receiver. It would be several decades
before the photophone's principles found their first practical applications in military
communications and later in fiber-optic communications.
2.2Radio
The term "wireless" came into public use to refer to a radio receiver or transceiver (a
dual purpose receiver and transmitter device), establishing its usage in the field of wireless
telegraphy early on; now the term is used to describe modern wireless connections such as in
http://en.wikipedia.org/wiki/Alexander_Graham_Bellhttp://en.wikipedia.org/wiki/Charles_Sumner_Tainterhttp://en.wikipedia.org/wiki/Photophonehttp://en.wikipedia.org/wiki/Light_beamhttp://en.wikipedia.org/wiki/Electromagnetic_radiationhttp://en.wikipedia.org/wiki/Electricityhttp://en.wikipedia.org/wiki/Laserhttp://en.wikipedia.org/wiki/Science_fictionhttp://en.wikipedia.org/wiki/Free_space_optical_communicationhttp://en.wikipedia.org/wiki/Military_communicationshttp://en.wikipedia.org/wiki/Military_communicationshttp://en.wikipedia.org/wiki/Fiber-optic_communicationhttp://en.wikipedia.org/wiki/Transceiverhttp://en.wikipedia.org/wiki/Transceiverhttp://en.wikipedia.org/wiki/Fiber-optic_communicationhttp://en.wikipedia.org/wiki/Military_communicationshttp://en.wikipedia.org/wiki/Military_communicationshttp://en.wikipedia.org/wiki/Free_space_optical_communicationhttp://en.wikipedia.org/wiki/Science_fictionhttp://en.wikipedia.org/wiki/Laserhttp://en.wikipedia.org/wiki/Electricityhttp://en.wikipedia.org/wiki/Electromagnetic_radiationhttp://en.wikipedia.org/wiki/Light_beamhttp://en.wikipedia.org/wiki/Photophonehttp://en.wikipedia.org/wiki/Charles_Sumner_Tainterhttp://en.wikipedia.org/wiki/Alexander_Graham_Bell8/4/2019 Wire Less Communication
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cellular networks and wireless broadband Internet. It is also used in a general sense to refer to
any type of operation that is implemented without the use of wires, such as "wireless remote
control" or "wireless energy transfer", regardless of the specific technology (e.g. radio, infrared,
ultrasonic) that is used to accomplish the operation. While Guglielmo Marconi and Karl
Ferdinand Braun were awarded the 1909 Nobel Prize for Physics for their contribution to
wireless telegraphy.
2.3Early wireless work
David E. Hughes, eight years before Hertz's experiments, transmitted
radio signals over a few hundred yards by means of a clockwork keyed transmitter. As this was
before Maxwell's work was understood, Hughes' contemporaries dismissed his achievement as
mere "Induction". In 1885, T. A. Edison used a vibrator magnet for induction transmission. In
1888, Edison deployed a system of signaling on the Lehigh Valley Railroad. In 1891, Edison
obtained the wireless patent for this method using inductance (U.S. Patent 465,971).
In the history of wireless technology, the demonstration of the theory of
electromagnetic waves by Heinrich Hertz in 1888 was important.[3][4] The theory of
electromagnetic waves was predicted from the research of James Clerk Maxwell and Michael
Faraday. Hertz demonstrated that electromagnetic waves could be transmitted and caused totravel through space at straight lines and that they were able to be received by an experimental
apparatus. The experiments were not followed up by Hertz.Jagadish Chandra Bosearound this
time developed an early wireless detection device and help increase the knowledge of millimeter
length electromagnetic waves.[5] Practical applications of wireless radio communication and
radio remote control technology were implemented by later inventors, such as Nikola Tesla.
2.4The electromagnetic spectrum
Light, colors, AM and FM radio, and electronic devices make
use of the electromagnetic spectrum. In the US, the frequencies that are available for use for
communication are treated as a public resource and are regulated by the Federal
Communications Commission. This determines which frequency ranges can be used for what
purpose and by whom. In the absence of such control or alternative arrangements such as a
http://en.wikipedia.org/wiki/Radiohttp://en.wikipedia.org/wiki/Infraredhttp://en.wikipedia.org/wiki/Ultrasonicshttp://en.wikipedia.org/wiki/Guglielmo_Marconihttp://en.wikipedia.org/wiki/Karl_Ferdinand_Braunhttp://en.wikipedia.org/wiki/Karl_Ferdinand_Braunhttp://en.wikipedia.org/wiki/Nobel_Prize_for_Physicshttp://en.wikipedia.org/wiki/David_E._Hugheshttp://en.wikipedia.org/wiki/Thomas_Edisonhttp://www.google.com/patents?vid=465971http://en.wikipedia.org/wiki/Electromagnetic_wavehttp://en.wikipedia.org/wiki/Heinrich_Hertzhttp://en.wikipedia.org/wiki/Wireless#cite_note-Story-2http://en.wikipedia.org/wiki/Wireless#cite_note-Story-2http://en.wikipedia.org/wiki/Wireless#cite_note-Story-2http://en.wikipedia.org/wiki/James_Clerk_Maxwellhttp://en.wikipedia.org/wiki/Michael_Faradayhttp://en.wikipedia.org/wiki/Michael_Faradayhttp://en.wikipedia.org/wiki/Transmission_(telecommunications)http://en.wikipedia.org/wiki/Receiver_(radio)http://en.wikipedia.org/wiki/Jagadish_Chandra_Bosehttp://en.wikipedia.org/wiki/Jagadish_Chandra_Bosehttp://en.wikipedia.org/wiki/Jagadish_Chandra_Bosehttp://en.wikipedia.org/wiki/Wireless#cite_note-4http://en.wikipedia.org/wiki/Wireless#cite_note-4http://en.wikipedia.org/wiki/Wireless#cite_note-4http://en.wikipedia.org/wiki/Nikola_Teslahttp://en.wikipedia.org/wiki/Federal_Communications_Commissionhttp://en.wikipedia.org/wiki/Federal_Communications_Commissionhttp://en.wikipedia.org/wiki/Federal_Communications_Commissionhttp://en.wikipedia.org/wiki/Federal_Communications_Commissionhttp://en.wikipedia.org/wiki/Nikola_Teslahttp://en.wikipedia.org/wiki/Wireless#cite_note-4http://en.wikipedia.org/wiki/Jagadish_Chandra_Bosehttp://en.wikipedia.org/wiki/Receiver_(radio)http://en.wikipedia.org/wiki/Transmission_(telecommunications)http://en.wikipedia.org/wiki/Michael_Faradayhttp://en.wikipedia.org/wiki/Michael_Faradayhttp://en.wikipedia.org/wiki/James_Clerk_Maxwellhttp://en.wikipedia.org/wiki/Wireless#cite_note-Story-2http://en.wikipedia.org/wiki/Wireless#cite_note-Story-2http://en.wikipedia.org/wiki/Heinrich_Hertzhttp://en.wikipedia.org/wiki/Electromagnetic_wavehttp://www.google.com/patents?vid=465971http://en.wikipedia.org/wiki/Thomas_Edisonhttp://en.wikipedia.org/wiki/David_E._Hugheshttp://en.wikipedia.org/wiki/Nobel_Prize_for_Physicshttp://en.wikipedia.org/wiki/Karl_Ferdinand_Braunhttp://en.wikipedia.org/wiki/Karl_Ferdinand_Braunhttp://en.wikipedia.org/wiki/Guglielmo_Marconihttp://en.wikipedia.org/wiki/Ultrasonicshttp://en.wikipedia.org/wiki/Infraredhttp://en.wikipedia.org/wiki/Radio8/4/2019 Wire Less Communication
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privatized electromagnetic spectrum, chaos might result if, for example, airlines didn't have
specific frequencies to work under and an amateur radio operator were interfering with the pilot's
ability to land an airplane. Wireless communication spans the spectrum from 9 kHz to 300 GHz.
(Also see Spectrum management)
France, the United Kingdom, Greece, Italy and Belgium. However, the reverse
holds, with fixed-lines outnumbering mobiles in the United States, Canada, and Argentina.
Penetration rates were close to equal in Japan in 2001, but in all countries, mobile penetration is
rising much faster than fixed lines.
The price for mobile phone services are difficult to compare between countries. In
part this reflects exchange rate variations, but more importantly pricing packages and the form ofpricing differs significantly between countries. Most obviously, different countries have different
charging mechanisms, with calling party pays dominating outside the United States. But in the
United States and Canada receiving party pays pricing often applies for calls to mobile
telephones. Different packages and bundling of equipment and call charges also make
comparisons difficult. A major innovation in mobile telephone pricing in the late 1990s was the
use of pre-paid cards. This system, where customers pay in advance for mobile calls rather than
being billed at a later date, has proved popular in many countries. For example, in Sweden, pre-
paid cards gained 25% of the mobile market within two years of their introduction (OECD, 2000,
p.11).
Despite the changing patterns of pricing, the OECD estimates that there was
a 25% fall in the cost of a representative bundle of mobile services over its member countries
between 1992 and 1998 (OECD, 2000, p.22).
http://en.wikipedia.org/wiki/Amateur_radiohttp://en.wikipedia.org/wiki/Airplanehttp://en.wikipedia.org/wiki/Spectrum_managementhttp://en.wikipedia.org/wiki/Spectrum_managementhttp://en.wikipedia.org/wiki/Airplanehttp://en.wikipedia.org/wiki/Amateur_radio8/4/2019 Wire Less Communication
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3. PRINCIPLES OF WIRELESS COMMUNICATIONS: -
Wireless communications begin with a message that is converted into an
electronic signal by a device called a transmitter. There are two types of transmitters: analogand digital. An analog transmitter sends electronic signals as modulated radio waves. The analog
transmitter modulates the radio wave to carry the electronic signal and then sends the modified
radio signal through space. A digital transmitter encodes electronic signals by converting
messages into a binary code, the series of zeros and ones that are the basis of all computer
programming. The encoded electronic signal is then sent as a radio wave. Devices known as
receivers decode or demodulate the radio waves and reproduce the original message over a
speaker.
Fig: Principle of wireless communication
Wireless communications systems involve either one-way transmissions, in
which a person merely receives notice of a message, or two-way transmissions, such as a
telephone conversation between two people. An example of a device that only receives one-way
transmission is a pager, which is a high-frequency radio receiver. When a person dials a pager
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number, the pager company sends a radio signal to the desired pager. The encoded signal triggers
the pagers circuitry and notifies the customer carrying the pager of the incoming call with a tone
or a vibration, and often the telephone number of the caller. Advanced pagers can display short
messages from the caller, or provide news updates or sports scores.
Two-way transmissions require both a transmitter and a receiver for sending
and receiving signals. A device that functions as both a transmitter and a receiver is called a
transceiver. Cellular radio telephones and two-way radios use transceivers, so that back-and-
forth communication between two people can be maintained. Early transceivers were very large,
but they have decreased in size due to advances in technology. Fixed-base transceivers, such as
those used at police stations, can fit on a desktop, and hand-held transceivers have shrunk in size
as well. Several current models of handheld transceivers weigh less than 0.2 kg (0.5 lb). Some
pagers also use transceivers to provide limited response options. These brief return-
communication opportunities allow paging users to acknowledge reception of a page and to
respond using a limited menu of options.
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4.TYPES OF WIRELESS COMMUNICATION: -
1. Infrared Wireless Transmission- "Transmission of data signals using infrared-lightwaves". These infrared-light waves are at a frequency too low for human eyes to receive
and interpret. Infrared ports can be found in digital cameras, laptops, and printers as well
as wireless mice.
2. Broadcast Radio- a wireless transmission medium that sends data over long distances(regions, states, countries) at up to 2 megabits per second (AM/FM Radio)
3. Microwave Radio- Transmission of voice and data through the atmosphere as superhigh-frequency radio waves called microwaves. These frequencies are used to transmit
messages between ground-based stations and satellite communications systems.
4. Communications Satellites- are microwave relay stations in orbit around the earth.4.1Wireless broadcast system: -
1) AM / FM radio2) Television3) Direct to home (DTH)
4.2Wireless networks: -
1) Personal Area Network (PAN)2) Local Area Network (LAN)3) Wireless Area Network( WAN)4) Wireless Metropolitan Area Network ( WMAN)
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5.Basic block diagram of communication system: -
I/P signal O/P signal
Fig: Block diagram of commn system
In simple block diagram contains only transmitter, medium and receiver.
This system can be easily affected by noise or external unwanted signal. An input signal is given
to transmitter from where the input analog signal is converted into electrical signal using
transducer.
Now the transmitter transmits information signal to receiver via wired or wireless
medium. The medium is nothing but a channel that used for exchange of data from one place to
another place. While message is been passed through medium it may be interrupted by unwanted
signal known as noise. Because of noise the size or width of information signal is increases due
to which at the receiver end it makes confusion for data collection.
At the receiver end there is opposite circuitry is used in transmitter. Here we get the
original signal from electrical signal.
Transmitter Medium
OR
Channel
Receiver
Noise
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6. Basic block diagram of Wireless communication: -
I/P signal O/P Signal
Fig: Block diagram of Wireless commn
Here in wireless communication system we uses trans-receivers at both sides along
with transducer at input and output sides. Here the wireless media stands for either air or
atmospheric layers like troposphere, ionosphere etc.
I/P
Transd
ucer
Trans-
receive
r
Wireles
s
Mediu
m
Trans-
receive
r
O/P
Transd
ucer
Noise
(Natural)
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7.Modulation : -
Modulation is a process by which a signal is transformed into waveforms that
are compatible with the characteristic of the channel, in terms of bandwidth support also.
7.1Bandwidth:-
It is a part of spectrum that is used for communication. Mathematically it can be
Stated as follow:
B.W. = Upper frequency - lower frequency
7.2Modulation system: -
It has two main types as follows:
Analog and digital modulation system which are further divided as analog into
Amplitude, Angle and Pulse modulation techniques. Where on other hand the digital modulation
is divided into Pulse amplitude modulation, Pulse width modulation, Pulse phase modulation and
Delta modulation.
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8.Economic Issues in Wireless Communications
Wireless communications and the economic goods and services
that utilise it have some special characteristics that have motivated specialised studies. First,
wireless communications relies on a scarce resource namely, radio spectrum. Second, use of
spectrum for wireless communications required the development of key complementary
technologies; especially those that allowed higher frequencies to be utilised more efficiently.
Finally, because of its special nature, the efficient use of spectrum required the coordinated
development of standards. Those standards in turn played a critical role in the diffusion of
technologies that relied on spectrum use.
Privatizations in the 1980s and 1990s, and the success of (at least
limited) mobile telephone competition in some countries, resulted in a more arms-length process
of spectrum allocation developing in the 1990s. Users of radio spectrum, and particularly users
of 2G and 3G mobile telephone spectrum, have generally been chosen by one of two broad
approaches since the early 1990sa beauty contest or an auction.
A beauty contest involves potential users submitting business plans to the
government (or its appointed committee). The winners are then chosen from those firms
submitting plans. There may be some payment to the government by the winners, although the
potential user most willing to pay for the spectrum need not be among the winners. For example,the U.K. used a beauty contest approach to assign 2G mobile telephone licenses in the 1990s.
Sweden and Spain have used beauty contests to assign
France used a beauty contest to assign four 3G licenses. The national
telecommunications regulator required firms to submit applications by the end of January 2001.
These applications were then evaluated according to preset criteria and given a mark out of 500.
Criteria included employment (worth up to 25 points), service offerings (up to 50 points) and
speed of deployment (up to 100 points). Winning applicants faced a relatively high license fee
set by the government. As a result, there were only two applicants. These firms received their
licenses in June 2001, with the remaining two licenses unallocated (Penard, 2002).
The concept of using a market mechanism to assign property rights over spectrum
and to deal with issues such as interference goes back to at least the 1950s when it was canvassed
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by Herzel (1951) and then by Coase (1959). But it was more than thirty years before spectrum
auctions became common. New Zealand altered its laws to allow spectrum auctions in 1989 and
in the early 1990s auctions were used to assign blocks of spectrum relating to mobile telephones,
television, radio broadcasting and other smaller services to private management (Crandall, 1998).
In August 1993, U.S. law was modified to allow the FCC to use auctions to assign radio
spectrum licenses and by July 1996 the FCC had conducted seven auctions and assigned over
2,100 licenses (Moreton and Spiller, 1998). This included the assignment of two new 2G mobile
telephone licenses in each region of the U.S. through two auctions.9
In 2000, the U.K. auctioned
off five 3G
Formally, the FCC spectrum auctions were for personal communications
services (PCS). In addition to 2G mobile telephones, relevant services included two-way paging,
portable fax machines and wireless computer networks. See McAfee and McMillan (1996) for an
early appraisal of these auctions.
Licenses for a total payment of approximately $34b. Auctions have involved a
variety of formats including second price sealed bid in New Zealand, modified ascending bid in
the U.S. and a mixed ascending bid and Dutch auction format in the U.K.
Bidders may have to
satisfy certain criteria, such as service guarantees and participation deposits, before they can
participate in the auctions. Limits may also be placed on the number of licenses a single firm canwin in a particular geographic area, so that the auction does not create a monopoly supplier.
From an economic perspective, using an auction to assign spectrum helps ensure that the
spectrum goes to the highest value user.
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9.Diffusion and Demand for Mobile Telephony
Diffusion
While standardization appears to increase the rate of diffusion of mobile
technology within a country, what else affects the rate of take up of mobile phones? Gruber and
Verboven (2001b) estimate the diffusion of mobile technology over the fifteen states in the
European Union using an S-shaped diffusion path.
They address a number of specific issues:
For a non-technical overview of the diffusion of mobile telephones in the EU,
see Gruber (1999). Gruber and Verbovens analysis suggests that the move to 2G systems in
Europe led to a rapid increase in the diffusion of mobile technology. This diffusion effect was
significantly greater than the acceleration effect built in to an S-shaped diffusion process.
However, Gruber and Verboven do not isolate the cause of this acceleration. One explanation is
standardization. 2G technology was introduced using the GSM standard across the EU, replacing
a variety of incompatible analogue systems. Thus, the network effects associated with roaming
may underlie the increased diffusion. Alternatively, as noted above, 2G mobile systems are
significantly more efficient in terms of spectrum use than analogue systems. The capacity
expansion associated with the introduction of 2G systems could lead to a drop in prices that
encourages mobile take-up, regardless of the degree of competition..
competition hypothesis, they find that mobile demand is decreasing in
price, although only the effect of monthly charges is statistically significant. Koski and
Kretschmer (2002) do not consider catch up explicitly but do find that countries with a higher
GDP per head adopted 2G technology earlier. This is consistent with Ahn and Lee (1999).
Gruber and Verboven (2001a) also find that countries with higher income per capita tend to be
more advanced in adopting mobile phones. (p.1204) Further, they consider convergence in
terms of the level of a countries development and show that convergence in diffusion of mobile
technology is much faster in rich countries than in poor countries. Thus, a late starter among
poorer nations will take a lot longer to catch up with an early starter than would a comparable
late starter among rich countries.
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10.Security
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11.The relation between wireless & mobile technology
Are fixed-line telephones and mobiles complements or substitutes in
demand? Theoretically, the answer is ambiguous. To the extent that mobile telephones offer
similar call functions to fixed-line telephones, we would expect there to be substitution in
demand (Woroch, 2002). But mobile telephones are often used for short calls that would not be
possible on a fixed-line telephone and such calls are often made to or from fixed-line telephones.
Thus, the diffusion of mobile technology increases the benefits accruing to a fixed-line
subscriber, potentially increasing demand for fixed-line services.
In the U.K., OFTEL concluded on the basis of qualitative survey evidence
that fixed-line and mobile telephones, to a significant degree, are complements. [T]he advent of
the mobile has, to a significant degree, expanded the market for making calls, rather than
substituting for fixed calls, implying that a large majority of mobile calls are complementary to
fixed calls.
This conclusion is backed up by Gruber and Verboven (2001a). [C]ountries
with a large fixed network tend to be more advanced in adopting mobile phones. (pp.1024-5)
While this effect is diminishing over time, Gruber and Verboven conclude that the fixed
network is largely viewed as a complement to mobile phones. Similarly, Anh and Lee (1999)find that [t]he number of fixed lines per person has a positive influence on the probability of
mobile telephone subscription.
A number of recent studies, however, suggest that mobile and fixed-line
telephony are substitutes in demand. Horvath and Maldoom (2002) criticize the OFTEL
conclusion as potentially confusing complementarity with individual tastes. If individuals who
have a greater propensity to make telephone calls tend to have both mobile and fixed-line
telephones then simply noting the correlation between ownership does not give any information
about the degree of substitution between mobile and fixed-line services. They use survey data to
try and correct for this taste effect, concluding that an individuals spending on fixed -line
telephony decreases significantly when the individual also has a mobile telephone.
While Horvath and Maldoom consider call spending, other studies relate
mobile and fixed-line penetration rates. Cadima and Barros (2000) find that the ability to access
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mobile telephony reduces demand for fixed-line services. The availability of mobile services
leads to approximately a ten percent decrease in the fixed-wire telephony.
11.1Costs
A small number of papers have attempted to determine the presence of scale economies
in mobile telephony. The results from these studies tend to be contradictory. While McKenzie
and Small (1997) find that mobile telephony generally exhibits diseconomies of scale, and at best
has constant returns to scale, Foreman and Beauvais (1999) find that mobile telephony exhibits
modest increasing returns to scale.
The disagreement between such cost studies is unsurprising. In fixed-line local
telephony, the presence or absence of increasing returns to scale has been subject to heated
debate for much of the last thirty years (e.g. see Shin and Ying, 1992). In local telephony, the
debate has immediate regulatory implications regarding the presence or absence of a natural
monopoly in the local loop. In contrast, for 2G mobile, robust competition has been shown to be
viable in many
11.2 Regulation and Competition
This section surveys the literature dealing with possible anticompetitive behaviour in
wireless markets and the associated regulation of wireless services. The focus is on issues that
are of potential concern to policy makers including potential barriers to wireless competition
(arising from incomplete coverage, roaming, standards, and number portability), the possibility
of tacit collusion, discriminatory on- and off-net pricing, and the regulation of access prices.
11.3Limitations of wireless competition
Given the success of wireless services, at least in terms of the spectacular growth in
cellular subscriptions (see section 2.3 for details), it is perhaps surprising that a main focus for
the economics literature on wireless has been on the limitations of wireless competition. To some
extent this probably reflects the historical structure of the industry, which given the allocation of
scarce spectrum often only allowed two networks to exist, for example in the U.S. and U.K.. A
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natural question to ask is whether two networks are enough to ensure competitive conditions, a
question we will address in section 5.1.1 which reviews the literature on tacit collusion in
wireless markets.
Section 2 introduced several other properties of the wireless market that might cause
policymakers to be concerned about the likely levels of competition and prices. These included
sunk costs, high switching costs (lock-in occurs through long-term contracts, a lack of phone
portability and a lack of number portability), differentiation in coverage, and inconsistent
standards. In section 5.1.2 we review the competition and regulatory aspects of these issues. We
also review the literature relating to pricing in wireless markets, dealing with the possibility of
discriminatory on- and off-net pricing and the high price of international roaming.
Broadly speaking, there are three different access prices that are of interest in wireless markets.
1. A call from a mobile operator to a fixed-line network (a mobile-to-fixed call) involves the
mobile operator collecting all the revenue for the call, but the fixed-line network
providing the termination of the call. As a result, the fixed-line network usually charges
for the termination of mobile-to-fixed calls. Typically, the termination of mobile-to-fixed
calls is treated in the same way as the termination of other calls to fixed-line networks,
being regulated on a cost-basis.
2. A call from a fixed-line network to a mobile operator (a fixed-to-mobile call) often leads
to an access price being set by the mobile operator. In the majority of markets, the
termination of fixed-to-mobile calls has been priced many times higher than the
termination of mobile-to-fixed calls, sometimes resulting in the regulation of fixed-to-
mobile termination prices.32
An exception is the U.S., where this access price is the same
as the mobile-to-fixed access price due to the symmetry requirements under the 1996
Telecommunications Act. Other exceptions are Canada, Hong Kong and Singapore,
where there are no fixed-to-mobile termination charges. Instead, like the U.S., mobile
operators recover the cost of terminating fixed-to-mobile calls from the mobile callers
directly (receiver pays).
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3. A call from a mobile operator to another mobile operator (a mobile-to-mobile call) may
involve mobile operators charging each other for termination. Such access prices are
often negotiated privately between mobile operators.
In this section we will review the recent literature that has developed on fixed-to-
mobile termination, dealing with the related issues of caller versus receiver pays and mobile-to-
mobile interconnection as we go.
The first paper to model the optimal pricing of fixed-to-mobile termination was that
of Armstrong (1997). Armstrong noted the high price of fixed-to-mobile calls in the
Mobile termination charges are regulated in the U.K using a price-cap approach,
with the cap reducing towards estimates of long-run incremental cost over four years. In
Australia the regulator ties year-on-year changes in mobile termination charges to changes in
retail prices of mobile services.
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12.Difference between Wireless and Cordless
The term "wireless" should not be confused with the term "cordless", which
is generally used to refer to powered electrical or electronic devices that are able to operate from
a portable power source (e.g. a battery pack) without any cable or cord to limit the mobility of
the cordless device through a connection to the mains power supply. Some cordless devices, such
as cordless telephones, are also wireless in the sense that information is transferred from the
cordless telephone to the telephone's base unit via some type of wireless communications link.
This has caused some disparity in the usage of the term "cordless", for example in Digital
Enhanced Cordless Telecommunications.
In the last fifty years, wireless communications industry experienced drastic
changes driven by many technology innovations.
Armstrong assumes mobile operators are perfectly competitive and
symmetric. There are a fixed number of subscribers that the mobile operators compete for. Each
mobile operator is assumed to charge the same amount for terminating fixed-to-mobile calls, and
earns a margin equal to this termination charge less its costs of terminating calls.34
Competition
drives mobile operators to return this margin to its subscribers, which takes the form of a subsidy
to consumers to connect to the network. Armstrong argues that high fixed-to-mobile termination
charges can explain the handset subsidies so often observed in the wireless market.
Assuming fixed-line operators obtain no margin on fixed-to-mobile calls,
Armstrong shows the socially optimal fixed-to-mobile termination charge is equal to cost. This
ensures fixed-to-mobile calls are priced at cost, which is the only source of a possible
inefficiency in the model. Such cost-based termination of fixed-to-mobile calls eliminates any
subsidy to mobile subscribers.
Armstrong considers how optimal termination charges change when threeEven back in 1997, these issues had already been dealt with by regulation in the U.S. The 1996
Telecommunications Act already required that fixed-to-mobile termination be priced at the same
level as mobile-to-fixed termination, and fixed-to-mobile retail prices be regulated on the same
In his model, mobile-to-mobile calls and mobile-to-fixed calls do not play any role in the
analysis.
http://en.wikipedia.org/wiki/Cordlesshttp://en.wikipedia.org/wiki/Link_(telecommunications)http://en.wikipedia.org/wiki/Digital_Enhanced_Cordless_Telecommunicationshttp://en.wikipedia.org/wiki/Digital_Enhanced_Cordless_Telecommunicationshttp://en.wikipedia.org/wiki/Digital_Enhanced_Cordless_Telecommunicationshttp://en.wikipedia.org/wiki/Digital_Enhanced_Cordless_Telecommunicationshttp://en.wikipedia.org/wiki/Link_(telecommunications)http://en.wikipedia.org/wiki/Cordless8/4/2019 Wire Less Communication
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13.1Advantages : -
It overcome the distance and language barrier. Effective over wide area. It requires less maintenance. High speed. Time consuming. It provides better security. It can overcome the noisy effect.
13.2Disadvantage: -
It cant overcome on natural noise. Requires large bandwidth. It may damage electronic devices due to stronger electromagnetic waves.
13.3Future Scope: -1) In domestic application.2) In routine life.3) In networking.
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14.Applications of wireless technology
01.Security systems
Wireless technology may supplement or replace hard wired implementations in security systems
for homes or office buildings.
02.Television remote control
Modern televisions use wireless (generally infrared) remote control units. Now radio waves are
also used.
03.Cellular telephone (phones and modems)
Perhaps the best known example of wireless technology is the cellular telephone and modems.
These instruments use radio waves to enable the operator to make phone calls from many
locations worldwide. They can be used anywhere that there is a cellular telephone site to house
the equipment that is required to transmit and receive the signal that is used to transfer both voice
and data to and from these instruments.
04.Wi-Fi
Wi-Fi is a wireless local area networkthat enables portable computing devices to connect easily
to the Internet. Standardized as IEEE 802.11 a,b,g,n, Wi-Fi approaches speeds of some types of
wired Ethernet. Wi-Fi hot spots have been popular over the past few years. Some businesses
charge customers a monthly fee for service, while others have begun offering it for free in an
effort to increase the sales of their goods.
05.Wireless energy transfer
Wireless energy transfer is a process whereby electrical energy is transmitted from a power
source to an electrical load that does not have a built-in power source, without the use of
interconnecting wires.
http://en.wikipedia.org/wiki/Cellular_telephonehttp://en.wikipedia.org/wiki/Wireless_modemhttp://en.wikipedia.org/wiki/Local_area_networkhttp://en.wikipedia.org/wiki/Internethttp://en.wikipedia.org/wiki/IEEE_802.11http://en.wikipedia.org/wiki/Ethernethttp://en.wikipedia.org/wiki/Ethernethttp://en.wikipedia.org/wiki/IEEE_802.11http://en.wikipedia.org/wiki/Internethttp://en.wikipedia.org/wiki/Local_area_networkhttp://en.wikipedia.org/wiki/Wireless_modemhttp://en.wikipedia.org/wiki/Cellular_telephone8/4/2019 Wire Less Communication
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06.Computer Interface Devices
Answering the call of customers frustrated with cord clutter, many manufactures of computer
peripherals turned to wireless technology to satisfy their consumer base. Originally these units
used bulky, highly limited transceivers to mediate between a computer and a keyboard and
mouse, however more recent generations have used small, high quality devices, some even
incorporating Bluetooth. These systems have become so ubiquitous that some users have begun
complaining about a lack of wired peripherals.Wireless devices tend to have a slightly slower
response time than their wired counterparts, however the gap is decreasing. Initial concerns
about the security of wireless keyboards have also been addressed with the maturation of the
technology.
Many scientists have complained that wireless technology interferes with their experiments,
forcing them to use less optimal peripherals because the optimum one is not available in a wired
version.This has become especially prevalent among scientists who use trackballs as the number
of models in production steadily decreases.
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