| Historical relic is very important fortune left by our ancestors. It carries a long history of our country, reflecting the people's activities, social relationships and ideology in different periods in various geography. Meanwhile, cultural relic also embodies the heritage of human knowledge, the situation of people transforming the nature, supplying valuable information for later generations. Museum provides a platform for preservation and exhibition. To monitor the environment of museum can be very helpful for detecting potential damage and taking appropriate action to protect the treasures.Cooperated with faculty of environment, this paper brings Quartz Crystal Microbalance technology into environment monitoring. By measuring the quality changes of the crystal sensor, the content of the polluting gas can be calculated by using Sauerbrey formula. It builds an intelligent monitoring system to implement data collection, processing and uploading to the monitoring centre through a wireless network. This system has many advantages, such like real-time monitoring, monitoring various regions simultaneously, easily maintenance and so on. Researchers can be freed from the processes to collect information, and just analysis the final data directly. Then, they can setup rating system for museum to improve the relic keeping environment.There are two main tasks in this subject. One is the design of a stable crystal oscillator circuit. This paper implements a CMOS inverter gate oscillator circuit. The circuit has a simple structure, easy to implement. The other one is the realization of the frequency measurement circuits. This paper uses Verilog HDL language to implement precision frequency measurement in a CPLD chip.Moreover, this paper designs a development board for detection unit, implements a wireless communication protocol based on the Modbus RTU protocol to achieve data uploading and builds software architecture of DLL combining with LabVIEW to do data processing and results display.
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