Research On Voice Compression And Transmission System Of Elevator Calls

At present,with the popularization of the Internet of Things in major cities across the country,intelligent buildings have also become the focus of development and construction.Elevator system is an indispensable device in the construction of urban buildings,and its safety has always been the focus of attention of manufacturers and users.Relevant documents issued by the state stipulate that elevators as special equipment must be equipped with secure voice calling equipment to be listed.Therefore,it is the focus of this paper to study and design a stable speech transmission system suitable for this application.In the above background,there are different degrees of defects in the transmission distance and transmission stability of the current schemes on the market.Because the elevator is a relatively closed system,in a complex electrical operating environment,it will be affected by various interferences and signal shielding.In order to improve these deficiencies,this paper mainly studies how to perform high-quality voice compression and transmission in elevator calls..We based on ARM's M4 core chip as a research platform.Because the M4 core integrates efficient DSP and floating-point arithmetic unit,the algorithm code execution speed can be improved.After comparing various speech algorithms and considering the actual product cost,the speex speech algorithm is finally used to implement this research.In order to ensure a balance between the stability of transmission and the distance of transmission,considering the security,the efficiency of transmission,and the saving of cables,CAN BUS is finally selected as the medium for transmitting voice.This thesis is divided into six chapters,which introduces the background and research significance of elevator voice call research,elevator call system network structure,speex voice codec technology,CAN bus and data transmission,and the realization and summary of the system.