Design And Research Of Multi-functional Interphone Based On Lora

Digital walkie-talkie is the most widely used mobile terminal in the field of special mobile communication.It has low cost and easy to use.In low power wide area network(LPWAN),a new generation of communication technology,LoRa(Long Range),has emerged,which runs in unauthorized bands.Its low power consumption,low cost,long distance,low complexity and other characteristics are suitable for the Internet of Things and data acquisition and other fields.Based on the research of current digital walkie-talkie technology and the transmission characteristics of LoRa and Bluetooth Ble,this paper defines a set of communication rules to coordinate the two communication technologies in the transport layer.At the same time,a design scheme of multifunctional walkie-talkie based on LoRa communication technology is proposed.Firstly,the communication principle of LoRa is analyzed.The mechanism model,transmission guarantee mechanism and the influence factors of spread spectrum modulation are studied.The overall structure and system composition of LoRa are determined.In the hardware design of the system,STM32 chip is used as the core processor to control LoRa spread spectrum chip SX1278,Bluetooth Ble chip nrf52832,vocoder module and OLED display module.In the aspect of transport layer software design,the protocol stacks of LoRa and Bluetooth Ble are studied respectively,and the compatibility of the two communication protocols is coordinated through the self-defined protocol mechanism,so as to improve the overall performance of data transmission.In the aspect of mobile software design,based on Xcode software platform of Mac OS system,this paper uses Objective-C language to design a mobile app software application.The APP application interface is friendly and easy to operate.It is mainly used for Bluetooth connection with the walkie-talkie.It can display data transmission content in the walkie-talkie.The data service function of the walkie-talkie is expanded on this APP software.Finally,the LoRa multifunctional walkie-talkie is tested and analyzed in detail.The results show that the system can meet the design requirements well in data transmission and other functions.This design is different from the current digital walkie-talkie.It greatly improves the anti-jamming ability of walkie-talkie,enhances the transmission distance and expands more data service functions.At the same time,the hybrid networking design of the two communication technologies solves the problem of low power consumption and long-distance two-choice in current wireless communication,and avoids the problems of multi-interference,channel congestion,channel resource constraints and so on.It provides some reference and reference value for the application of high-performance walkie-talkie.