Design Of Large Number Of Concurrent Connections Of Remote Monitoring Systemfor Vegetable Greenhouse

The development of agriculture is the foundation of social development and advance.With the rapid development of science and technology,the management of greenhouse has been developing towards intelligent direction,and greenhouse monitoring system plays an extraordinary important status in the development of agriculture.Traditional greenhouse monitoring system more selected wire transmission to manage and monitor the greenhouse.This way requiredto lay a lot of cables in the greenhouse,not only the constructionwas difficult but also the maintenance of the system lately was also very difficult.In addition the main control chip of the traditional greenhouse monitoring system was controlled by ordinary MCU.The function of the ordinary MCU wassimple,it was difficult to meet the needs of the function and performance of the modern greenhouse.With the greenhouse area expanding unceasingly and the greenhouse number increasingunceasingly,the data that monitoring system handled was increasedand server performance was degraded.How to reduce the operating cost of the greenhouse and raise the running efficiency of greenhouse to realize environmental parameters accurately controlled of in greenhouse,and how to monitorand manage the scattered and remote greenhouses centrally become important issue to be studied and solved.This paper taking vegetable greenhouse as an example,combining embedded,wireless sensor technology,wireless communication technology and vegetable greenhouse monitoring system together organically,designed a long distance monitoring system for vegetable greenhouses with large number of concurrent connections.Aiming at the function that the system needs to realize,the systemwascomposed of two parts: the host computer and the lower computer.The high concurrency server model based on epoll and thread pool technology was designed in host computer,which solved the problem of limited performance when the server handledmore than ten thousands data of vegetable greenhouse environmental information.The lower computer selected the S3C2440 embedded core board as the main control processing part,controlled the Zig Bee wireless communication module,the camera module,the CDMA module and the equipment module.Zig Bee wireless communication module realized the collection and transmission of environmental parameter and plant growth status in vegetable greenhouse.The camera module realized the function of video monitoring of plant growth in vegetable greenhouse.Then using established communication operator,the greenhouse information was transferred long distance through CDMA module.So that users could not be limited by distance and geographical to treatlarge number of concurrent connections in the greenhouseefficiently and stably,monitored and processed the informationpersistently.Finally,the system was tested,including remote control function test,video monitoring function test,theperformance of large number of client concurrent connection test.Testing result meet the initial design requirement and design effect.