Studying On The Cold Chain Monitoring System Of Xinjiang Fresh Food Grape Based On ZigBee

With the rapid development of the national economy and the significant changes in the dietary structure of the consumers,the consumption idea of fresh and distinctive agricultural products is changing from the traditional single to the modern diversification and high-speeding,the demand for fresh and quality safety agricultural products is increasing.However,due to the perishable characteristics of agricultural products,there are serious losses during the cold storage and transportation,which seriously damaged nutrition and commercial value of fresh grape.Therefore,carrying out seamless monitoring and tracing method,ensuring the effective collection,real-time transmission and processing in the cold chain logistics has become a focal point need to be solved in today's society.First of all,this article through field research to understand the flow and status of Xinjiang table grape cold-chain logistics.Compared the effect of different concentration fresh air to the mechanism of fresh grape quality change During Xinjiang ordinary temperature logistics and cold chain logistics process.According to the experimental results,compared with other treatment groups,the concentration of 3%O₂+10%CO₂ fresh-keeping gas is most conducive to the storage of table grapes.Which provides a theoretical basis for designing a better comprehensive monitoring system for fresh grape cold chain logistics.Finally,determing that real-time monitoring to pre-cooling and refrigerating transport links in the cold chain logistics process should be carried to better guarantee the storage environment of fresh grape in the cold chain logistics process.Based on the analysis of the environmental parameters and the gas-preserved fresh gas ratio,a multi-sensor node and coordinator node were implemented based on the Zig Bee protocol and the CC2530 microprocessor.The multi-sensor integrated nodes can periodically collects the temperature,humidity,oxygen and carbon dioxide during the cold chain logistics of table grapes,the coordinator node organizes and receives data over the network to achieve real-time monitoring of temperature,humidity,fresh gas concentration and cold chain transport environment during refrigerated transport.The map call function of the monitoring center can be used to view the cold chain transportation environment and routes in real time,and the early warning and alarm modules can be used to realize feedback and control of dangerous events in the cold chain.Finally,on the basis of system design and implementation,the function tests of the individual modules and the tests of the overall performance were carried out respectively.According to the test results,ZigBee's packet loss-free transmission distance can reach about 50 meters under line-of-sight conditions,and the transmission distance is about 26 meters under non-line-of-sight conditions.It can be seen that in the case where the coverage of the cold chain truck is relatively small,the ZigBee non-line-of-sight transmission distance is sufficient to meet the practical application requirements of the cold chain monitoring.Finally,the linear regression model was used to perform the least squares estimation for each sensor module's test results.This can compensate the sensor measurement errors to a certain extent and improve the overall system monitoring accuracy.