Research Of Intelligent Wireless Digital Communication System

The development of science and technology has been boosting the industry automatic control system development into the direction of intelligent and wireless, particularly in computer technology, wireless communication technology, network technology, controlling technology, information technology. Most industry controlled terminals have mobile ability, which demand more intelligence, flexibility, simplicity and convenience wireless data communication system to fulfill the requirement of all-round automatic control. Therefore, intelligent wireless data transmission system has a broad prospect of application both in contemporary and future. The intelligent wireless data communication system concerning this project is designed for the electric wire poles monitoring system of An Hui municipal administration. The main research content is to build up a wireless data communication system and achieve considerable system intelligence. This wireless data communication system includes the need to design the wireless transceiver and power amplifier. This intelligent system consists of an auto-adjust power controller according to communication distance and an auto-select channel chooser interrelated with current transmitting channel. The system uses AT89S52 single chip computer as MCU to control receiving, transmitting and amplifying wireless signals. It links to computers via RS-232 serial port to transmit data to the central database, and joints to end-user's sensors through RS-232 serial port to collect data. It achieved remote monitoring by retrieving data of wire poles collected by sensor systems and transmit them to the remote computer at control center. The system has following features. It uses 433MHz ISM (Industry Science Medical) band as communication frequency, which is free of charge and reduce the cost. The built-in self diagnosing, warning, and terminating system assure the reliability of data transmission. Each wireless data transmission module has retransmission function, which can acquire long-distance data transmission without extra special repeater. It adjusts transmitting power and selects transmission channel automatically to decrease the consuming of energy on the basis of assuring communication quality and also reduce electromagnetic pollution and interference. The system has its unique characteristics such as, low cost, high communication reliability and high flexibility, addition to the feature of easy to install and use. It solved the problem of energy saving and channel interference within a wireless data transmission system and play a positive role in the development of wireless data transmission system.