Cold chain monitoring system is mainly used in refrigeration products, strict in temperature testing field of security monitoring, for refrigerated products in production, transportation, distribution, storage temperature and humidity environmental information monitoring, early warning, analysis, data storage and other services. The cold chain monitoring system based on wireless Internet technology for real-time acquisition of environmental temperature and humidity information, mainly adopts DTU terminal equipment and the cold chain collector, and through the GPRS network or ROOT uploaded to the system monitoring platform.Through the system monitoring platform on the real-time data change, managers can fully grasp the environmental information of the refrigerated goods, convenient decision makers to make interpretation and decision making. System features: 1, wireless networking Acquisition node of this cold chain monitoring system using wireless network in the form of a automatic frequency modulation, multipath routing, error correction coding, error retransmission, adaptive rate, such as mechanism, can maximum limit to guarantee the reliability and stability of the data transmission. Compared with wired network, wireless network no matter on the installation difficulty and cost of the new system is on the upgrade of the old system has great advantages. 2, low power consumption The monitoring system of acquisition node using battery power, the working current equipment mainly includes two parts of the control chip and radio frequency transmission. Control chip working current: the current 1.3 mA dormancy: 3 uA rf transmission work current: 25 mA dormancy current: 0.5 uA in accordance with the equipment work once every 5 minutes, each working 1 s calculation, power consumption is 0.09 mA/h per hour, a year of power consumption of about 790 mA/h, also said as long as the battery section of 1600 mA/h can make equipment work for 2 years. System is the main equipment 1, the concentrator: RTU terminals, the system adopts the concentrator is equivalent to a "black box" of equipment, it is responsible for field data acquisition, storage, transmission, control, and is the basis of system the implementation of a complete set of hardware.The RTU and the upper machine communication interface with GPRS and RS482 two kinds: GPRS for remote environmental monitoring, such as cold chain logistics links. RS485 is suitable for the local environment monitoring, such as cold chain of production, storage, link. 2, cold-chain collector: Collector is responsible for field data collection and upload, he have two kinds of working mode. Wake up regularly In this mode, the equipment for a period of time intervals, such as 5 minutes) wake up once, environmental information collection and upload your own tasks into low power mode, until the next time you wake up. Fixed-point awaken In this mode, the scene of the equipment by the concentrator to awaken, concentrator can be either all wake on LAN can awaken the designated equipment.Equipment in the same environment information collection to upload your own tasks into low power mode again.