The Designing Of Real-time Monitoring System Of CH₄Based On DSP

Social progress bring convenience to our lives, but also causes pollution to the environment, air pollution is an important aspect of the various forms of pollution, directly endanger the quality of human life and health.CH4,CO,CO2and CFCs are the main atmospheric greenhouse effect gas, the effect to the greenhouse of CH4is22times of CO2of the same concentration, therefore, detection and treatment of CH4becomes very important, TDLAS is widely used to detect the atmospheric pollutants, acquired signals using digital signal processing approach, it has the advantages of high accuracy, good stability. In this paper, the following areas are studied and discussed about the design of real-time monitoring system:(1) analysis and comparative the common methods of gas detection, giving an explanation of features and advantages of TDLAS technology, statement the development and application of digital signal processing technology.(2) Describing the principle of real-time monitoring system, including the application of spectroscopy techniques, the choice of the methane absorption and the principle of the wavelength modulation technique.(3) Proposing the hardware designing and the choice of experimental device of the real-time monitoring system. Including the designing of signal modulation circuit, the choice of light source and its drive, the designing of multiplier circuit and lock-in amplifier, finally, simply introduction the signal processing system.(4) The software designing of real-time monitoring of system, including the software design of the overall system, software designing of data acquisition, the software designing of data processing and simulation.