The Monitor System Of DC Remote Reserve Power Supply Of Pas Cell Station

In last few years, PAS( Personal Access System), the business of wireless local calls, develops rapidly by the unique market and the service advantage in the whole country, which brings the huge economic interests and social benefits to telecom operators. However, the problems of PAS cell station power supply affect the stability of its signal and seriously restrict its further development. Therefore, this thesis raises "commercial power and DC remote power supply" which is off-line power mode of Uninterruptible Power Supply to resolve the problems of PAS CS (cell station) power failure.The thesis adopts Microcontroller of AT89C52 as the center of system. Adopting multiplexing technique and making use of communication line between CSC (cell station controller) and CS to achieve simultaneous transmission of ISDN signal and electric power. According to the variation of circuit equivalent resistance to design detection circuit, which can judge that the line is short circuit or open circuit and the commercial power is working normally or failure. When the reserve power supply is working, the system judges its operation status by voltage and current detection circuit. Making use of the characteristic of the gas discharge tube to achieve suspension system detection of power line touching. Transmitting information collected up to PC by RS485 for the purpose of centralized monitoring.The thesis adopts "commercial power and DC remote power supply" to resolve the problem of PAS cell station power supply. CS power supply should adopt the method that commercial power is main power and the reserve power supply is assist power. When commercial power is failure, the system will switch immediately to reserve power supply and when commercial power return, which will switch to commercial power again to ensure CS power supply not failure. The thesis makes use of communication line between CSC and CS to achieve the power transmission, which can save the resources, short construction period and quick results.The product prototype of this thesis had been inspected in August 2004 by The Ministry of Information Industry Protective Performance of Communications Products Quality Supervising Test Center and installed commissioning in October 2004 and had got the user's good comments. So far, there has been 150 product or more in the market. Following the development and improvement of business of wireless local calls, the market share of the PAS goes on improving. However, the problem of CS power supply is the main problem of telecom operators. The subjectproduct, PAS CS power supply, is designed to resolve the problem. Following the further development of PAS, it's spreading and application must be have widely market prospect.