PERFORMANCE OF POWER LINE COMMUNICATION SYSTEMS WITH NOISE REDUCTION SCHEME FOR SMART GRID APPLICATIONS-Electronics ProjectsPosted: March 8, 2012
X10 protocol is meant for data communication over the power line which carries 230V, 50 Hz Ac supply. Here we are going to use the power line in the industry for data acquisition purpose. This is an improvement of data communication over the power line.
X10 is an international and open industry standard for communication among electronic devices used for home automation, also known as domotics. It primarily uses power line wiring for signaling and control, where the signals involve brief radio frequency bursts representing digital information.Whether using power line or radio communications, packets transmitted using the X10 control protocol consist of a four bit house code followed by one or more four bit unit code, finally followed by a four bit command.
In this paper, we propose clipping scheme and equalizer as methods to reduce the effects of impulsive noise and channel attenuation in power line communication (PLC) system. Clipping is cutting off the amplitude of the received signal over threshold level without its phase change in order to reduce noise effects. The equalizer compensates for effects of PLC channel. The performance is evaluated in terms of bit error rate (BER). From simulation results, it is confirmed that the proposed clipping scheme has slightly better performance than conventional PLC system. The results of the paper can be applied to PLC systems for smart grid.
The device is a hardware interface that allows control data communication over the power line. Its purpose is that of translating the serial output provided by some digital service, like a microcontroller, into a coded pulse train that is suitable for being transmitted over the usual domestic power lines. Conversely, the interface is able to extract such messages from the power line and to convert them into serial streams that the connected digital device can read. The interface therefore acts like a modem, allowing the employment of the common electrical supply network of a building as a local area network.
When coupled with a programmable digital device, such as a microprocessor or a microcontroller, the device allows the realization of “intelligent” and “communicative” equipments that can interact with similar objects over a domestic network, without the need of installing a dedicating wiring. Typical applications are in the field of Home and Building Automation (management of surveillance and alarm systems, home appliances automation, AMR (Automatic Meter Reader), Home automation control, Security and surveillance, General-purpose isolated transceiver.
The innovative feature of these devices is that they transmit data on the power line, using the concept of conveyed wave (zero crossing).We use an 8051 based microcontroller the at89c51 for the transmitter and the receiver. From a keypad on the transmitter the relay section on the receiver can be controlled.
- 565 Tone Generator
- 555 Timer
- LM386 Amplifier
- Power Supply.
- UM91214 DTMF Encoder s
- UMC 8870 DTMF Decoder
- Isolation Transformer
The main objective of this project is to implement an Pass word Based Door Locking System Using AT89c51 Microcontroller.
Security is a prime concern in our day-today life. Everyone wants to be as much secure as possible. An access control for doors forms a vital link in a security chain. The microcontroller based Door locker is an access control system that allows only authorized persons to access a restricted area. The system is fully controlled by the 8 bit microcontroller AT89C51 which has a 2Kbytes of ROM for the program memory. The password is stored in the EPROM so that we can change it at any time.
The system has a Keypad by which the password can be entered through it. When the entered password equals with the password stored in the memory then the Stepper motor rotate forward side so that the door is opened. If we entered a wrong password for more than three times then the Alarm is switched on. When we go inside and come back then the microcontroller will sense the person using the IR, the microcontroller will automatically open the door for you.
The default password is 1111 and you can change the password by dialing 1234, old password, and new password #button. for example if you want to change the password from the default to 4523 then dial 123411114523# after dialing you can hear a beep sound which confirm the operation goes successful.
- AT89c51 Microcontroller
- Stepper motor
- ULN2003 Motor Driver
- 5V Buzzer
- Embedded C
- KEIL Demo Version with Simulator
The project called ‘Digital Code Lock using AT89C2051′. LCD is used for display and a keyboard is used to input the keys. This project source code is written in C.
This a simple project with efficient hacking prevention from Brute Force etc. The basic user lock is of 5 Digits and Master Lock is of 10 digits so its not easy for an intruder to break the lock unless you keep the code simple.
The input is taken from a 4×3 Keypad (please see the schematic for more information) and Display the user input on a 2×16 LCD. A pin is assigned as output for activating and deactivating the lock. For demonstration an LED is connected to that pin.
The user has two options either he/she can use its own 5 digit code or use the default 5 digit code. If user has to do setup his own code, then he has to enter “12345″ and press ‘#’. After this.. controller will ask for 10 Digit master password which is preprogrammed in the controller. Entering master lock, user can enter the new 5 digit code for the lock and press ‘#’ to save it.
Keypad has 12 keys (4×3) starting from 1,2,3,4,5,6,7,8,9,*,0,# (please see the schematic for layout). Numeric keys are used for entering numbers. ‘*’ is used as the Cancel key and ‘#’ is used as the Enter key.