Miniaturized Airborne Wireless Sensor Design And Research

With the improvement of the function of airborne environmental monitoring system,the types and number of sensors installed have increased significantly.Traditional airborne sensors rely on cables for energy acquisition and data transmission,which makes the layout of sensors constrained by cable length and weight and poor flexibility.In addition,too many cables will increase the difficulty of later maintenance.Therefore,a miniaturized wireless sensor suitable for airborne environment is designed.Firstly,this paper designs the miniaturization of airborne wireless sensor hardware to realize accurate measurement on the premise of low power consumption and miniaturization.Through the overall design of hardware,the principle block diagram of wireless sensor is determined,and the microprocessor of wireless sensor is selected;through the on-chip ad configuration of STM32,the high-precision acquisition of sensitive signals is realized;through device selection and power management circuit design,the circuit power consumption is reduced,the battery volume is reduced,and the miniaturization of wireless sensor is realized;through the communication circuit design based on A7128 chip,the hardware basis of wireless sensor networking is provided.Secondly,according to high vibration intensity and the characteristics of small space in the airborne application environment,the microstrip antenna is selected as the airborne wireless sensor antenna,and the microstrip antenna and the wireless sensor shell are designed into a common antenna to reduce the volume of the wireless sensor and improve the overall anti vibration strength.The simulation model is built in HFSS software,and the antenna size,dielectric substrate size and antenna slot are simulated and analyzed to determine the optimal size of wireless sensor microstrip antenna.Thirdly,in order to make the wireless system to work efficiently and make rational use of power and energy,the working mode is divided into four states:sleep,wake-up,networking and data transmission;according to the requirements of915MHz communication frequency and 1～2Mbps communication rate,a wireless sensor data transmission mode based on TDMA is designed;configure MCU ADC program according to the frequency of collecting physical quantity;the program of A7128 wireless module is designed.Finally,through the comparison between airborne wireless sensor and wired sensor,the miniaturization degree of airborne wireless sensor is reflected,and the function of the whole WSN is tested through experiments.From results we can find that the center frequency,bandwidth and other parameters meet the expected standards of the design;the measurement accuracy of wireless sensor is good,and can work continuously for more than 50 hours;under the overall test,the network packet loss rate and bit error rate are controlled within 10^-5 and 10^-6.