基于WiFi的语音矿灯设计

Design of voice miner's lamp based on WiFi

针对现有矿灯大多只具有照明、定位、环境感知等功能,没有语音对讲功能的问题,设计了一种基于WiFi的具有语音对讲功能的语音矿灯。该语音矿灯以工业以太环网和WiFi网络为传输平台,采用VoIP语音通信技术实现语音播放、音频采集、与调度台对讲功能;通过音频编解码芯片实现语音模拟信号与数字信号的转换,采用UDP协议将信号传输至调度台,完成语音数据的双向传输,实现语音对讲和矿灯照明一体化。详细介绍了语音对讲功能实现的关键技术:音频数据的编码格式和缓存管理、语音数据的可靠传输机制,用于确保语音播放的准确性;WiFi模块与微控制器STM32L151的低功耗休眠技术,用于降低语音矿灯平均电流,延长工作时间。测试结果表明:该语音矿灯能够满足调度台与井下工作人员之间的语音对讲需求,与WiFi基站通信距离可达400 m,与调度台之间的对讲传输时延小于1 s,语音矿灯之间的组播传输时延小于3 s;语音矿灯对讲时平均电流小于70 mA,空闲时平均电流小于5 mA。

In order to solve the problem that most of the existing miner's lamps only have the functions of lighting,positioning,environment perception and so on,and do not have the voice intercom function,a voice miner's lamp with voice intercom function based on WiFi is designed.The voice miner's lamp takes industrial Ethernet ring network and WiFi network as transmission platform,and adopts VoIP voice communication technology so as to realize voice playback,audio acquisition,and intercom function with the dispatching center.The audio codec chip is used to realize the conversion of voice analog signal and digital signal,and UDP protocol is applied to transmit the signal to the dispatching center so as to complete the two-way transmission of voice data and realize the integration of voice intercom and miner's lamp lighting.This paper introduces the key technologies of voice intercom function in details.Audio data encoding format and cache management,reliable voice data transmission mechanism are used to ensure the accuracy of voice playback.The low-power sleep technology of WiFi module and microcontroller STM32L151 are used to reduce the average current of the voice miner's lamp and extend the working time.The test results show that the voice miner's lamp can meet the demand of voice intercom between the dispatching center and the underground workers,the communication distance between the voice miner's lamp and the WiFi base station can reach 400 m,the intercom transmission delay between the voice miner's lamp and the dispatching center is less than 1 s,and the multicast transmission delay between the voice miner's lamps is less than 3 s.The average current of the voice miner's lamp is less than 70 mA during intercom,and the average current is less than 5 mA during idle time.