19-12-2009, 07:57 AM
I am going to do project on Voice and data transmission and reception via LT power line.Please send me base paper and project materials
19-12-2009, 07:57 AM
I am going to do project on Voice and data transmission and reception via LT power line.Please send me base paper and project materials
19-12-2009, 07:56 PM
Data transfer method and system in low voltage networks
This describes data transmission in two-way communication via low-voltage systems that are linked to a higher order telecommunication network.Earlier tone frequency remote control system was there where data was transmitted in one-way communication systems through power lines. This system here enables use of the low-voltage systems of utility companies for two-way communication independent of other carriers. he quality of the signal transmission is strongly polluted by the omnipresent noise, heavily jammed due to a variety of loads and unpredictable effects on signal propagation. For this reason, practical implementation of the high quality transmission through the powerline remains nowadays a difficult issue. Summary It uses a higher-order telecommunications networkand data transmission within the low-voltage system takes place at a high-frequency range of up to 30 MHz using band spreading of data signals and a transmitting level below the specified interference or noise voltage limit .The said band-spread data is given a direction coding to specify a logical direction within the low-voltage system using different sequences of a family of pseudo-random numbers to enable multiple-user operation. A correlator placed at an attenuation-dependent distance identifies and regenerates the binary sequences of data. A direction coding using code, time, or frequency multiplexing converts the physical separation which is impossible with data transfer in low-frequency systems. The proposed method of data transmission at a high frequency range facilitates low-cost bidirectional data transmission in real time via the low-voltage systems of utility companies if buried cables are used.overall transmission capacity of the low-voltage line between connected users channels in ISDN quality with a data rate of 64 kbps can be provided. further developments pseudo-random sequences such as Gold sequences is used for user-specific band spreading. the logical direction of the data stream is preset using code multiplexing. The band-spread signals are transmitted in the transmit and receive directions on separate frequency bands or time slots.A CDMA processor for spreading the data using allocated spread sequence and adding the direction code, a modulator for modulating the signals onto a particular carrier frequency, a controllable amplifier to adjust the input level required at the receiving end are used. for detailed description and drawings, download report: Data transfer method and system in low voltage networks.pdf (Size: 248.47 KB / Downloads: 213) also refer this IEEE article: http://ieeexplore.ieeeXplore/login.jsp?u...ision=-203
13-08-2012, 09:38 AM
Power Line Carrier Communication
Power Line Carrier.docx (Size: 54.29 KB / Downloads: 60) PLCC : - Power Line Carrier Communication is an approach to utilize the existing power lines for the transmission of information. In today’s world every house and building has properly installed electricity lines. By using the existing AC power lines as a medium to transfer the information, it becomes easy to connect the houses with a high speed network access point without installing new wirings. This technology has been in wide use since 1950 and was mainly used by the grid stations to transmit information at high speed. Now a days this technology is finding wide use in building/home automation as it avoids the need of extra wiring. The data collected from different sensors is transmitted on these power lines thereby also reducing the maintenance cost of the additional wiring. In some countries this technology is also used to provide Internet connection. History : - The idea of using an existing medium to send the communication signals is as old as the telegraph itself. But it had not been possible until the recent decades. The first significant step in the field was when two patents were issued to American Telephone and Telegraph Company in the name of 'Carrier Transmission over Power Circuits' in 1920. After four years later in 1924 two other patents were filed for the systems transmitting and receiving communication signals over three phase power lines. Harsh characteristics of the power cables were the key problem in further development. Researchers were involved to overcome the unpredictable characteristics of the power lines. Since the early 1980, spread spectrum power line communication was the main focus of the research. This technology is now developed far better than that initial improvement and is promising a reliable utilization in home automation and security systems. Operating Principle : - The communication device used for the communication over the power lines is a MODEM, commonly known as Power Line MODEM (PLM). It works as both transmitter and receiver, i.e., it transmits and receives data over the power lines. A power line modem not only modulates the data to transmit it over the power lines and but also demodulates the data it receives from the power lines. By using modulation techniques, binary data stream is keyed on to a carrier signal and then coupled on to the power lines by PLM. At the receiver end another PLM detects the signal and extracts the corresponding bit stream. Advantage and Disadvantage : - In order to completely analyze the advantages and disadvantages of PLCC technology, we look into its basic application that is access to telecommunication networks. From the economic standpoint, it is very reasonable to use a pre installed wired network instead of running new wires. It certainly reduces a lot of time & money and so is the biggest advantage of the technology. In many countries, PLCC is becoming a reliable high speed source to get Internet. And in some places, especially in remote areas, PLCC technology thankfully made it possible to avail internet connections. Power line communication is quite different in characteristics than the conventional dedicated wirings. Comparatively, it is a harsh medium and data transfer through it can create a lot of problems. Household appliances like halogen tubes, washing machines, televisions, etc. can become prone to an unpredictable noise and interference in the transmission. Continuous plugging and unplugging of electronic devices makes power line characteristics vary constantly.
22-10-2012, 11:09 AM
to get information about the topic "POWER LINE CARRIER COMMUNICATION" full report ppt and related topic refer the link bellow
https://seminarproject.net/Thread-power-...ion--14681 https://seminarproject.net/Thread-power-...munication |
|