关于使用WASN进行声能映射的挑战:同步和音频捕获
Emiliano Ehecatl García-Unzueta1, Paul Erick Mendez-Monroy2, Caleb Rascon3
1Posgrado de Ingeneria Electrica, Universidad Nacional Autónoma de México (UNAM), Universidad 3000, Mexico City 04510, Mexico.
Sensors (Basel, Switzerland)
|July 11, 2023
概括
无线声学传感器网络 (WASN) 可实现声能映射,但存在同步问题. 精确时间协议 (PTP) 与本地音频录制提供了最可靠的数据捕获,用于准确的声音源分析.
科学领域:
- 声学和信号处理
- 无线传感器网络 无线传感器网络
- 实时数据采集 实时数据采集
背景情况:
- 声能映射需要精确的时间来准确地定位使用光束成形技术的源.
- 无线声学传感器网络 (WASN) 提供了实际的部署,但在节点间同步方面面临着挑战.
- 现有的同步协议可能无法满足用于可靠的声数据捕获的严格时间要求.
研究的目的:
- 评估不同同步协议对声能映射WASN数据可靠性的影响.
- 为了比较WASN同步的网络时间协议 (NTP) 和精确时间协议 (PTP).
- 在WASN框架内评估各种音频数据捕获方法.
主要方法:
- 使用配备MEMS麦克风的Raspberry Pi 4B+节点实现WASN.
- 评估用于同步WASN节点的网络时间协议 (NTP) 和精确时间协议 (PTP).
- 三种音频捕获策略的比较:本地录制 (两种方法) 和网络传输 (一种方法).
主要成果:
- 实验结果表明,精确时间协议 (PTP) 与NTP相比,提供了更高的同步精度.
- 当地音频数据记录方法比通过无线网络传输数据更可靠.
- 通过PTP同步和本地记录的结合,为声能映射提供了最可靠的数据.
结论:
- 精密时间协议 (PTP) 是用于声能映射的WASN推的同步方法.
- 当地音频录制对于维护WASN部署中的数据完整性至关重要.
- 优化的同步和数据捕获对于使用WASN准确的声源表征至关重要.
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