Characteristics of communication systems

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Transcript Characteristics of communication systems

University of Pitesti and
Dolnośląska Wyższa Szkoła Przedsiębiorczości i Techniki w
Polkowicach
Communication systems
-presentation-
STUDENT: CONSTANTIN IONUT
DR INZ. ZDZISŁAW PÓLKOWSKI
Polkowice-2015
TOPICS MENU
• Definition
• Characteristics of communication systems.
• Examples of communication systems.
• Transmitting and receiving in communication systems.
• Other information processes in communication systems.
• Issues related to communication systems.
DEFINITION
Communications system:
A collection of individual communications networks, transmission systems,
relay stations, tributary stations, and data terminal equipment (DTE)
usually capable of interconnection and interoperation to form an integrated
whole. (188) Note: The components of a communications system serve a
common purpose, are technically compatible, use common procedures,
respond to controls, and operate in unison.
http://www.its.bldrdoc.gov/fs-1037/dir-008/_1140.htm
Characteristics of communication systems
A communication system has 5 main components. All of which function
together to create a helpful and create an operational system that properly
communicates.
A Data Source: This where the data is originally made or sent from. An
example of this could be a networked computer.
The Data Source then sends the data to the Transmitter: This is where
the data is encoded
into a form
useful for thesystems.
transmission medium to
Characteristics
of communication
send.
The Transmitter sends the data along the Transmission Medium to a
Receiver: There the data will be decoded from the form that it was sent in.
This will enable the Destination to read the data in the correct format.
The Destination: This is where the data finally completes it's trip and
arrives. The destination is simply the place where the data was directed to
at the start of the Communication System.
http://www.boredofstudies.org/wiki/Characteristics_of_communication_systems
Below is an image regarding characteristics of
Communicatin Systems
http://www.conceptdraw.com/solution-park/computer-and-networks
Transmitter:
A set of equipment used to generate and transmit electromagnetic
waves carrying messages or signals, especially those of radio or
television.
http://electronics-lab.com/projects/rf/012/
http://www.oxforddictionaries.com/definition/english/transmitter
In computer programming, Source Data or data source is the primary
location from where data comes. The data source can be a database, a
dataset, a spreadsheet or even hard-coded data. When data is
displayed in a web page or desktop application, in a column-row format
or other formats, the data are retrieved from its data source and
presented in the format defined in the programming.
Computer applications can have multiple data sources defined,
depending on its function. Applications like Oracle, SalesForce.com,
and SAP all use databases as data sources. A common type of
database is an SQL database, but some applications can use other
types of databases, like Microsoft Access. While less stable, a series of
spreadsheets can be used as a data source, but this is less common
due to the chance of spreadsheets becoming corrupted as their size
increases.
http://www.computerhope.com/jargon/s/sourdata.htm
Transmission Medium
Data is represented by computers and other telecommunication devices
using signals.Signal are transmitted in the form of electromagnetic energy
from one device to another. Electromagnetic signals travel through
vacuum, air or another transmission mediums to travel between one
point to another(from source to reciver).Electromagnetic energy( includes
electrical and magnetic fields) includes power, voice, visible light, radio
waves,
ultraviolet light, gamma rays etc.
http://www.studytonight.com/computer-networks/transmission-mediums
Reciver
A simple receiver is just that: simple. A general simple receiver will consist
of a low-pass filter (to remove excess high-frequency noise), and then a
sampler, that will select values at certain points in the wave, and
interpolate those values to form a smooth output curve. In place of a
sampler (for purely analog systems), a general envelope filter can also be
used, especially in AM systems. In other systems, different tricks can be
used to demodulate an input signal, and acquire the data. However simple
receivers, while cheap, are not the best choice for a receiver.
http://www.zen22142.zen.co.uk/Circuits/rf/amrec.html
http://en.wikibooks.org/wiki/Communication_Systems/Coherent_Receivers
Examples of Communication Systems
Typical examples of communication systems are line telephony and line
telegraphy, radio telephony and radio telegraphy, radio broadcasting, pointto-point communication and mobile communication, computer
communication, radar communication, television broadcasting, radio aids
to navigation, radio aids to aircraft landing etc.The earliest communication
system namely line-telegraphy originated in eighteen forties (1840s). In
addition to this, line telephony came a few decades later whereas radiocommunication could become possible in the beginning of twentieth
century on invention of triode valve. Radio communication was further
greatly improved during World War II. It becomes more widely used
through the invention of transistor, integrated circuits (ICS) and other
Semiconductor devices in the subsequent years. Also in recent years,
communication has become more widespread with the use or satellites and
fiber optics. Today, there has been an increasing emphasis on the use of
computer in communication.
http://meaningofcommunication.blogspot.in/2010/04/communication-system.html
Example of communication systems
https://www.eurocontrol.int/articles/list-example-constituents-and-standards-cns-domain
Transmitting and receiving in communication
systems
Transmission of information from a source to a destination can be
performed in many ways by the use of electrical signals and electricelectronic circuits. To design a communication system is primordial to
define some parameters, such as, the physical medium in which the signal
will be transmitted, the way in what the signal would be generated and the
nature of signal, it means if the signal will be analogical or digital. In this
work, a communication system was designed, built up and debugged to
transmit and receive two kinds of signals by the use of an unique transmit
medium in a simultaneously way. One of these signals is an analogical
NTSC video signal and the other is a digital data signal from a PC
application.
http://ieeexplore.ieee.org/xpl/login.jsp?tp=&arnumber=4470525&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all
.jsp%3Farnumber%3D4470525
The purpose of this system is to transmit, in a safe and efficient way,
coded information from a PC to another by the combination of signals
with the Time Division Multiplexing technique (TDM), using a coaxial
cable as the physical medium of transmission.
To achieve this purpose the system is conformed by hardware
elements such as, the PIC16F874 micro-controller and software
elements implemented as a communication protocol to identify the
information transmitted. This document shows all the information about
circuits, tests and images from oscilloscope related with the
communication system.
http://scienceaid.co.uk/physics/waves/communication.html
http://ieeexplore.ieee.org/xpl/login.jsp?tp=&arnumber=4470525&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2F
abs_all.jsp%3Farnumber%3D4470525
Other information processes in communication
systems
COLLECTING
Collecting data for a communication system involves generating the data to
be transmitted. Collecting data involves a range of collection devices to
gather different types of data. The choice of device depends on the
application and the type of data to be transmitted. Some devices include:
•ATM terminals for electronic banking
•EFTPOS terminals for a retail store
•telephones for voice mail
•keyboards for email
•video cameras for a surveillance system.
http://en.wikibooks.org/wiki/HSC_Information_Processing_and_Technology/Communications#Other_Information_Processes
Proccesing
We examine and compare the different types of linear transmit
processing for multiple input, multiple output systems, where we
assume that the receive filter is independent of the transmit filter
contrary to the joint optimization of transmit and receive filters. We can
identify three filter types similar to receive processing: the transmit
matched filter, the transmit zero-forcing filter, and the transmit Wiener
filter. We show that the transmit filters are based on similar
optimizations as the respective receive filters with an additional
constraint for the transmit power. Moreover, the transmit Wiener filter
has similar convergence properties as the receive Wiener filter, i.e., it
converges to the matched filter and the zero-forcing filter for low and
high signal-to-noise ratio, respectively. We give closed-form solutions
for all transmit filters and present the fundamental result that their
mean-square errors are equal to the errors of the respective receive
filters, if the information symbols and the additive noise are
uncorrelated.
http://ieeexplore.ieee.org/xpl/login.jsp?tp=&arnumber=1468466&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2F
abs_all.jsp%3Farnumber%3D1468466
Data Conversing
CLIENT-SERVER
ARCHITECTURE
describes
the
software
relationships between the client (user) and the server. A client sends a
request to the server according to an agreed protocol and the server
responds. It provides a convenient way to interconnect programs that
are distributed across different locations in a network. Most business
applications and the Internet use client-server architecture. The Web
browser is a client program that requests services from a Web server to
complete the request.
http://en.wikibooks.org/wiki/HSC_Information_Processing_and_Technology/Communications#Other_Information_Proces
ses
Displaying
Electronic display system capable of displaying communication signal
strength on individual electronic display modules and method of using the
same. In one preferred embodiment of the present invention, a pseudoprice change command is transmitted by a base communication station to
an individual electronic display module and the strength of the
acknowledgment signal returned by the individual electronic display
module is observed and temporarily recorded. The base communication
station then transmits a command to change the electronic display on that
particular electronic display module to display the value of the received
communication signal strength.
http://www.google.tl/patents/US5604923
Issues related to communication systems.
When
communicating
such factorssystems.
remain largely unknown.
Issues
related electronically
to communication
In cyberspace relationships can be built on common interests and needs.
Information and knowledge is shared between people who may never
physically meet. People who would not (or could not) normally
communicate face-to-face can freely express and share their ideas and
knowledge online. These people are free to converse without prejudice.
However all is not perfect, this freedom can easily be abused by the
unscrupulous. Electronic communication systems, and in particular the
Internet, allow information to be shared quickly and relatively anonymously.
http://msciptcommunications.weebly.com/issues-related-to-communication-systems.html
Unscrupulous persons are able to masquerade as trusted others in order
to fraudulently obtain personal information such as credit card or banking
details. Most people presume their email messages to be private; in reality
network administrators and others with suitable access rights are able to
view and monitor emails. Those in control of networks are able to restrict
and monitor the activities of users. Such power relationships are often
legitimate, however as is the case with all such relationships power can be
abused. The Internet has removed national and international boundaries.
We are free to communicate and trade internationally. Individual
governments have little control over international trade and furthermore
enforcing international laws is expensive and often ineffective in
cyberspace. For example sending spam (mass electronic junk mail) is
illegal within Australia; however Australian law has no control over spam
sent from off shore locations. To cover all possible issues arising when
using communication systems is clearly not possible.
http://msciptcommunications.weebly.com/issues-related-to-communication-systems.html