Research On Intelligent Induction System Of High Speed Mist Area Based On LPWAN

In order to lower the impact of fog weather on highway traveling and transportation,the intelligent guidance system for fog area is being tested and popularized with the development of ITS in recent years.However,the existing intelligent guidance system still has poor stability and short operating life,the wireless communication of the system requires multi-level forwarding,and the information publishing capabilities is limited due to the poor network access.So,the topic of LPWAN-based intelligent guidance system is proposed in this paper.The emerging LPWAN technology in IoT field has been applied to the construction of highway intelligent guidance system,and based on the existing highway intelligent guidence system,an extended study was conducted.The research contents mainly include: comparing and evaluating several major protocols of LPWAN,analyzing its application scenarios and characteristics,and selecting LoRa which is one of LPWANs as the communication protocol of intelligent guidance system.According to the target of the project,the architecture of the intelligent guidance system is analyzed and designed,and the functional requirements of each subsystem are planned.A feasible design scheme is proposed too.The hardware design and software design of the induction slave are realized in terms of stability and reliability,so that the working life of the induction slave is improved,and the function of default detection and reporting is provided.The MQTT lightweight network application protocol is adopted to realize the vehicle detection data release between the host and the server to improve the information release capability of the system,and accelerate the construction of the highway intelligent transportation system.After experiments and tests,LPWANs has obvious advantages over other wireless communication methods in the highway.The effective communication distance of the LoRa module used in this paper is 3km,which can meet the communication between any nodes of a single road segment of the intelligent guidance system.With the star network topology,the link congestion problem caused by multi-level forwarding of short-range wireless communication can be effectively avoided,and the power consumption of the communication module is saved.The functional test of the induced slave shows that the stability and reliability design of the slave can be enhanced from various aspects such as power management,infrared modulation,default detection,failure protection,and woking status report.The MQTT test platform shows that MQTT can transmit packets with a small number of bytes in large quantities,which is suitable for multi-packet transmission applications.With the development and popularization of IoT,there will be more and more technology being used in ITS.This paper combines IoT and the intelligent guidance system,and applies the emerging LPWAN technology to the system construction.With practical economic benefits and value,it has also made certain explorations in the intelligent transportation of expressways.