Communication systems-presentation-

DR INZ. ZDZISŁAW PÓLKOWSKI

Polkowice-2015

University of Pitesti andDolnośląska Wyższa Szkoła Przedsiębiorczości i Techniki w

Polkowicach

STUDENT: CONSTANTIN IONUT

• 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.

TOPICS MENU

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

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 A Data Source: This where the data is originally made or sent from.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 the transmission medium to 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

http://www.conceptdraw.com/solution-park/computer-and-networks

Below is an image regarding characteristics of Communicatin Systems

Transmitter:A set of equipment used to generate and transmit electromagnetic waves carrying messages or signals, especially those of radio or television.

http://www.oxforddictionaries.com/definition/english/transmitter

http://electronics-lab.com/projects/rf/012/

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

ReciverA 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://en.wikibooks.org/wiki/Communication_Systems/Coherent_Receivers

http://www.zen22142.zen.co.uk/Circuits/rf/amrec.html

Examples of Communication Systems

Typical examples of communication systems are line telephony and line telegraphy, radio telephony and radio telegraphy, radio broadcasting, point-to-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 radio-communication 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

https://www.eurocontrol.int/articles/list-example-constituents-and-standards-cns-domain

Example of communication systems

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 electric-electronic 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://ieeexplore.ieee.org/xpl/login.jsp?tp=&arnumber=4470525&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Farnumber%3D4470525

http://scienceaid.co.uk/physics/waves/communication.html

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%2Fabs_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_Processes

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 pseudo-price 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.

Issues related to communication systems.

When communicating electronically such factors remain largely unknown. 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