Yu Xiaoyu

Design of Multi-parameter Wireless Sensor Network Monitoring System in Precision Agriculture

Precision Agriculture is an important direction of modern agriculture development, its main thought of technology is that we can acquire differences and space distribution through getting crops growth environment factors and growth conditions of ideal growing environment in time. We can analyze the reasons of the difference of crop yields and take effective control measures quickly. So this article designed a multi-parameter wireless monitoring system based on STM32F107 chip. The purpose was to monitor the parameters of the current crop growth environment. The hardware part of monitoring system was mainly divided into the optical path and electric circuit. The optical path structure refered to the system optical path part when using the test of soil organic matter content of the center wavelength of 850 nm near infrared light emitting diode (led), the incident and reflected light transmitting fiber and photoelectric diode. Circuit part mainly transmitted various environmental parameters of the signal to the minimum system for data processing and transmitted the data to PC for display and storage through the wireless communication mode. Experiment proved that this system could completely meet the daily precision agriculture for crop growth environment and the requirements of monitoring on the soil composition content, and the system had high reliability, the function was easy to extend.

Dust-concentration measurement based on Mie scattering of a laser beam

To realize automatic measurement of the concentration of dust particles in the air, a theory for dust concentration measurement was developed, and a system was designed to implement the dust concentration measurement method based on laser scattering. In the study, the principle of dust concentration detection using laser scattering is studied, and the detection basis of Mie scattering theory is determined. Through simulation, the influence of the incident laser wavelength, dust particle diameter, and refractive index of dust particles on the scattered light intensity distribution are obtained for determining the scattered light intensity curves of single suspended dust particles under different characteristic parameters. A genetic algorithm was used to study the inverse particle size distribution, and the reliability of the measurement system design is proven theoretically. The dust concentration detection system, which includes a laser system, computer circuitry, air flow system, and control system, was then implemented according to the parameters obtained from the theoretical analysis. The performance of the designed system was evaluated. Experimental results show that the system performance was stable and reliable, resulting in high-precision automatic dust concentration measurement with strong anti-interference ability.