Design And Implementation Of The Precise Timing Gateway Based On Telecommunication Network

Time service technology is a technology that transmits the standard time to the systems and terminals that need accurate time in various ways,so that the local time of the systems and terminals can be synchronized with the time source.With the development of the Internet of Things,the demand for time service is increasing day by day.The number of equipment terminals requiring precise time is increasing,and the scale is becoming larger and larger.The service range of China's long-wave and short-wave timing systems is relatively limited.The commonly used satellite-based timing systems have occlusion problems,and the cost for wireless terminals is relatively high.Relying on a wide range of telecommunication network to provide time service,the time service ability is strong,which can well meet the terminal's time requirements.However,when many wireless terminals cannot directly access the telecommunication network,it is necessary to design a gateway to forward the time information.The gateway serves as an extension of the telecommunication network timing,and provides timing services to the wireless terminal of the Internet of Things.Based on the analysis and research of timing technology,this thesis designed and implemented the precise timing gateway based on telecommunication network.The gateway realizes the conversion of the time service protocol.The time side uses the NTP and PTP protocols to connect to the telecommunication network platform to complete the precise time.The time service side provides the corresponding time service through three wireless transmission protocols and terminal connections.The precise timing gateway mainly includes soft terminal communication module for access to the telecommunication network,time synchronization module for NTP and PTP timing modes,the offset monitoring and reporting module,local clock module for stable punctuality,terminals access management module,three wireless timing mechanisms based on Wireless-Fidelity,Bluetooth and ZigBee functional modules.The mainly work of this thesis is as follows:1.The NTP and PTP time-consuming methods are designed to achieve precise time consumption for gateway system based on telecommunication network.The precise timing gateway runs the soft terminal to access base station connected to the telecommunication network platform through air interfaces to obtain the standard time.The time synchronization between the gateway and the platform under the NTP and PTP protocols is achieved respectively.The designed and developed NTP time program filters time deviation data to reduce errors.The designed PTP time solution applies the PTP protocol under Ethernet to the telecommunication network.The actual test results show that the two time-consuming methods for the gateway to access the telecommunication network can obtain better time synchronization accuracy.2.Designed and implemented three wireless timing mechanisms based on Wireless-Fidelity,Bluetooth and ZigBee modes,to provide corresponding timing services to multiple types of Internet of Things time-consuming terminal devices.The timing mechanism based on Wireless-Fidelity converts gateway PTP time and NTP timing.The system time synchronized with the platform's' PTP time is used as the time source,and the local NTP server is configured to provide timing services to the terminal.The timing mechanism based on Bluetooth,two timing modes,active broadcast and request response,are designed to publish the system time of the gateway to the terminal.The timing mechanism based on ZigBee improves accuracy by measuring the delay of sending and receiving time messages.The wireless time service terminal represented by the smart reminder pill box presents the time service effect of the gateway.3.Developed the management plane of the gateway.Designed and implemented the monitoring-reporting module and the terminal access management module,which together form the management plane of the gateway,and improve the system management capability of the gateway by saving the time information for reporting the gateway and collecting and analyzing the time accuracy of the terminal.The gateway mainly implements the functions of accessing to the telecommunication network in precise time and providing three wireless timing services,which ensures the time accuracy of the gateway system and improves the current situation of many wireless devices in the field of Internet of Things lacking effective time services.