Deepu creation

 List of subject for electronic and communication engineering students:- 1. Mathematics  2. Physics  3.  Network  theory  4. Basic electronic engineering  4. Signals and system 5. Switching theory and logic design 6. Electronic devices and circuits 7. Vlsi 8. Embedded systems       All subjects are used in future for getting a good job and knowledge. 

List of companies for ece students for getting jobs:- 1.  Intel 2. Qualcomm  3. Cisco 3.  Microstrip communication  4.  Semiconductor nxp 5. Xilinx 6.   Texas instrument  7. Infotech 8. Reliance  9. Bel 10. Bhel 11. NAloc 12. Npac 13.general electronics 14.dell 15. Samsung  16. Motorola 17. Arm 18.honey well 19 Sony 20 LG 21. Wipro 22. Red pipe 23.tcs 24. Infosys  25. Videopron 26. Siemens  27.safran engineering service 28.  philips 29 .generic motors 30 .  Tech Mahindra 

  Topology:- Topology defines the structure of the network of how all the components are interconnected to each other. There are two types of topology: physical and logical topology. Physical topology is the geometric representation of all the nodes in a network. Bus Topology :- o The bus topology is designed in such a way that all the stations are connected through a single cable known as a backbone cable. o Each node is either connected to the backbone cable by drop cable or directly connected to the backbone cable. o When a node wants to send a message over the network, it puts a message over the network. All the stations available in the network will receive the message whether it has been addressed or not. o The bus topology is mainly used in 802.3 (ethernet) and 802.4 standard networks. o The configuration of a bus topology is quite simpler as compared to other topologies. o The backbone cable is considered as a "single lane" through which the message is broadcast...

  Introduction to Communication and Networking What is Signal ? A signal is an electromagnetic or electrical current that is used for carrying data from one system or network to another. The signal is a function that conveys information about a phenomenon. In electronics and telecommunications, it refers to any time-varying voltage that is an electromagnetic wave which carries information. A signal can also be defined as an observable change in quality such as quantity. There are two main types of signals: Analog signal and Digital signal. Analog Signal Analog signal is a continuous signal in which one time-varying quantity represents another time-based variable. These kind of signals works with physical values and natural phenomena such as earthquake, frequency, volcano, speed of wind, weight, lighting, etc. Here, are essential characteristics of Analog Signal  These type of electronic signals are time-varying  Minimum and maximum values which is either positive or negati...

Disadvantages:- Optical Communication System Microwave System 1. Expensive transmitter and receiver. 1. Simple and less expensive transmitter and receiver. 2. Difficult coupling. 2. Easy coupling. 3. Power transmission depends upon the quantum efficiency of light source (LED or LASER). 3. Output power is directly coupled to the transmission line. APPLICATIONS OF OPTICAL FIBER COMMUNICATIONS:- 1) Long distance tele communications:- Long distance telephone carriers use optical fibers to carry the plain old telephone service (POTS) across their high speed “backbone” systems That carry thousands of voice signals between regions of country. The telephone industries first widespread use of fiber optics was between the central offices which are several kms apart and even, these are connected by fiber cables operating at 800-900nm. 2) Medical Applications:- The first commercial applications for fiber optics were medical. Bunaled fibers can deliver illumination light to remote regions...

    THE GENERAL COMMUNICATION SYSTEM AND ANALOG OPTICAL COMMUNICATION SYSTEM Diagram 1 represents the general communication system. The function is to convey the information from the information source over the transmission medium og destination.  OPTICAL COMMUNICATIONS:- 1) Information source:-  Any communication system serves to communicate either a massage or information, this massage originates in the information source. The message can be in the form of words, group of words, code symbols etc., out of these only the desired message is selected and conveyed. The part of the message which is conveyed is called information. 2) Transmitter:-  The message from the information source may or may not be in electrical nature. If the message is not an electrical signal, then it has to be converted into an electrical signal by means of transducer.  For example, in radio broadcast transmitter, a microphone converts the information in the form of sound wav...

  HISTORICAL DEVELOPMENT  In 1880 Alexander Graham Bell reported the transmission of speech using light beam. The photophone proposed by Bell just four years after the invention of telephone modulated sunlight with a diaphragm giving speech transmission over a distance of 200m.  However, some investigation of optical communications continued in early 1900s but its use was limited to low capacity communication links. It was due to lack of suitable light sources and the problem that light is restricted to line of sight and is severely affected by rain , fog, dust and atmospheric turbulence. Therefore, in ensuring years, an increasingly larger portion of the electromagnetic spectrum was utilized for conveying information transfer through radio and microwaves which provide to be most suitable.  From radio and microwave communication systems, we expect more capacity. The information carrying capacity is directly linked to bandwidth frequency extent of the modul...