Research And Implementation Of Io T Wireless Communication Network Based On LoRa

Lo Ra WAN is the current mainstream Lo Ra communication network,but it has the following three shortcomings: the collision probability of uplink communication is high;the transmission latency of downlink communication is long;the flexibility of network deployment is poor.In order to improve these shortcomings,some people have designed new Lo Ra communication networks based on Lo Ra physical layer,but they all have their own limitations.This paper designed and implemented a general Lo Ra communication network,which can meet the communication needs of most Io T applications and improve the existing Lo Ra communication network.The main work of this paper is as follows:Firstly,the Lo Ra physical layer was analyzed,and the shortcomings of Lo Ra WAN and TDMA-based Lo Ra communication networks were pointed out.Secondly,a general Lo Ra communication network M-Lo Ra was designed.In M-Lo Ra,for the characteristics of different types of uplink communication,the MAC protocol based on synchronous TDMA and the MAC protocol based on pure ALOHA were designed respectively,which effectively reduce the collision probability of uplink communication.The multi-reporting period mechanism,the adaptive data rate mechanism,and the random backoff mechanism were integrated in the MAC protocol,which effectively improve the performance of the network.In addition,for the low power consumption characteristics of the node devices,a wake-up mechanism was designed to effectively reduce the transmission latency of downlink communication.M-Lo Ra can be deployed independently or in combination with Lo Ra WAN,which increase the flexibility of network deployment.Finally,the hardware design and software design of M-Lo Ra were implemented on the embedded platform,and the function and performance of M-Lo Ra were tested.The test results show that for synchronous uplink communication,M-Lo Ra can achieve a communication success rate of 99.5%.In addition,the M-Lo Ra gateway can wake up nodes and complete downlink communication within 16 seconds.