Design Of Multi-Channel Temperature And Humidity Sensors Acquisition Systems And Portable Display System

In some fields of weather detection, acquisition of temperature and humidity is important in meteorological hazards forecasting, accurate numerical prediction, weather modification, meteorological monitoring. In some measurement environment, multi-channel data acquisition is needed to obtain the detailed distribution of temperature and humidity. In the occasion of ground meteorological station and weather reconnaissance aircraft, checking the waveform and storing the data of temperature and humidity are needed. In these places, the acquisition system and display terminal, which are small, light-weight and power efficient, are desired.According to the multi-point observation of meteorological observation station and meteorological aircraft airborne measurement environments, an acquisition system based on HIH-5031humidity sensor and Pt100platinum resistance temperature sensor is proposed. Temperature and humidity data are received by FPGA and then sent to the display terminal which is based on an ARM11processor. The terminal runs ARM-Linux system and Qt/Embedded application. SQLite3database is installed in the system to receive and store the data from sensors.Distribution of multi-channel acquisition can accurately show the environmental parameters, and find the data error of the individual sensors. In a test chamber, an optical chilled mirror dew point sensor is used as a standard to perform a comparison test. Under common temperature and humidity conditions, the error of the relative humidity is less than1.8%, and the error of temperature is less than0.18℃. The circuit of the sensor response quickly. The real-time waveform display is accurate and stable. The design would be used in a variety applications.