10-12-2012, 06:46 PM
Wireless Data Encryption and Decryption for Secured Communication using RF
Wireless Data Encryption.doc (Size: 925.5 KB / Downloads: 48)
Abstract:
Data Security is primary concern for every communication system. There are many ways to provide security data that is being communicated. However, what if the security is assured irrespective of the hackers are from the noise. This Project describes a design of effective security for data communication by designing standard algorithm for encryption and decryption.
The source information is generated by a key Board and this will be encrypted and is sent to destination through RF communication. The receiving system will check the data and decrypt according to a specific algorithm and displays on the LCD.
The RF modules used here are acts as a Transceiver. Encrypted information at the Transceiver end will send the information to the other end were this decrypted data will be displayed. And note that at the decrypted end the user has to press a special key “Decryption “as that they can get the as it is information on the 16X2 LCD.
This project uses regulated 5V, 500mA power supply. 7805 three terminal voltage regulator is used for voltage regulation. Bridge type full wave rectifier is used to rectify the ac out put of secondary of 230/12V step down transformer.
RF PRO (Rf Pocket Reference Oscillator):
Crystek’s new RFPRO series, RF pocket reference oscillator is an industry first! A Complete sine wave saw (surface acoustic wave) oscillator has been integrated in a rugged Sma housing. Simply connect +3.3vdc to the female sma side, and it will output A clean -135dbc/Hz phase noise signal at 10khz offset. In effect, each rfpro is A fixed frequency portable signal generator with an operating temperature of -20°c to 70°c. Available off the shelf in 500 MHz and 1 GHz frequency output. Perfect for lab use.
Wireless Communication:
Wireless communication, as the term implies, allows information to be exchanged between two devices without the use of wire or cable. A wireless keyboard sends information to the computer without the use of a keyboard cable; a cellular telephone sends information to another telephone without the use of a telephone cable. Changing television channels, opening and closing a garage door, and transferring a file from one computer to another can all be accomplished using wireless technology. In all such cases, information is being transmitted and received using electromagnetic energy, also referred to as electromagnetic radiation. One of the most familiar sources of electromagnetic radiation is the sun; other common sources include TV and radio signals, light bulbs and microwaves. To provide background information in understanding wireless technology, the electromagnetic spectrum is first presented and some basic terminology defined.
POWER SUPPLY:
The input to the circuit is applied from the regulated power supply. The a.c. input i.e., 230V from the mains supply is step down by the transformer to 12V and is fed to a rectifier. The output obtained from the rectifier is a pulsating d.c voltage. So in order to get a pure d.c voltage, the output voltage from the rectifier is fed to a filter to remove any a.c components present even after rectification. Now, this voltage is given to a voltage regulator to obtain a pure constant dc voltage.
MICROCONTROLLERS:
Microprocessors and microcontrollers are widely used in embedded systems products. Microcontroller is a programmable device. A microcontroller has a CPU in addition to a fixed amount of RAM, ROM, I/O ports and a timer embedded all on a single chip. The fixed amount of on-chip ROM, RAM and number of I/O ports in microcontrollers makes them ideal for many applications in which cost and space are critical.
The Intel 8052 is a Harvard architecture, single chip microcontroller (µC) which was developed by Intel in 1980 for use in embedded systems. It was popular in the 1980s and early 1990s, but today it has largely been superseded by a vast range of enhanced devices with 8052-compatible processor cores that are manufactured by more than 20 independent manufacturers including Atmel, Infineon Technologies and Maxim Integrated Products.
8052 is an 8-bit processor, meaning that the CPU can work on only 8 bits of data at a time. Data larger than 8 bits has to be broken into 8-bit pieces to be processed by the CPU. 8052 is available in different memory types such as UV-EPROM, Flash and NV-RAM.
The microcontroller used in this project is AT89S52. Atmel Corporation introduced this 89C51 microcontroller. This microcontroller belongs to 8052 family. This microcontroller had 128 bytes of RAM, 4K bytes of on-chip ROM, two timers, one serial port and four ports (each 8-bits wide) all on a single chip. AT89S52 is Flash type 8052.
The present project is implemented on Keil Uvision. In order to program the device, Proload tool has been used to burn the program onto the microcontroller.
The features, pin description of the microcontroller and the software tools used are discussed in the following sections.