Abstract:Targeted at the shortcomings of long distance data transmission difficulties through wired communication and vulnerable to information leak because of signal amplification through relay devices, this research puts forward interface circuit design, calibration algorithm and application program design interface circuit using 73K222AU modem, HR219307 transformer and AT89S52 Singlechip, which can effectively solve the problems of remote data transmission and control. The experimental results show that the proposed scheme has the advantages of long data transmission distance, high reliability, convenient communication network, and strong adaptability to environment etc.