The Development Of High Precision Digital Infrared Surface Temperature Sensor

Earth’s surface temperature is an important parameter in Geosciences. It’s accurate measurement plays a vital role in many areas. Currently, ground temperature element in automatic weather stations is obtained through platinum resistance temperature sensor. However, the use of platinum resistance to measure surface temperature can be easily influenced by multiple environmental factors, and with many measurement errors. The second generation AWS infrared surface temperature assessment uses infrared surface temperature as an element of observation, but still uses analog infrared temperature sensors. It is necessary to obtain temperature through data collector processing. This paper developed a radiation temperature measurement theory based digital infrared surface temperature sensor, designed to overcome the shortcomings of traditional sensors of ground temperature, to obtain a more accurate surface temperature.This paper designs a MSP430-based digital infrared surface temperature sensor using the Stefan-Boltzmann law. First, details of the infrared radiation theory and the characteristics of infrared radiation of land surface. After the comparison of several commonly used radiation thermometry, we select the most suitable for measuring the surface temperature as the temperature measurement basis of the present sensor. Then, through a series of laboratory performance comparison test, we decide to use pyroelectric infrared detector as the temperature measurement route of the present sensor and choose the TPD1T0224 pyroelectric infrared detector and structure and deduce the temperature measurement model. In terms of hardware, we first design the optical part based on the actual conditions of observation of surface temperature to determine the viewing angle and distance sensor coefficient. Second, we do the design of circuit and PCB system board according to the specific features and characteristics of each circuit block. In terms of the software, presentation on the specific function of each software module through a small part of the main flow chart and code in addition to doing nonlinear correction to digital shape machine using performance tests in Lab and BP neural network information fusion. Finally, the performance of a series of laboratory tests to evaluate the design of the sensor measurement error in the blackbody platforms and the factors that influence the error lies, and by comparing actual field trials to assess the accuracy of the observation sensor in actual geothermal observation.