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Updated: May 9, 2025

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In Situ Soil Moisture Sensors in Undisturbed Soils
Published on: November 18, 2022
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非常低频盆地尺度遥测观测的季节性依赖性
Kay L Gemba1, Geoffrey F Edelmann2
1Department of Physics, Naval Postgraduate School, Monterey, California 93943, USA.
JASA express letters
|May 1, 2025
概括
这项研究证明了长距离位置,导航和时间 (PNT) 消息的可靠水下声通信. 分析显示,用于盆地规模声学遥测的平均通道容量为0.028位/sHz.
科学领域:
- 海洋学 海洋学 海洋学
- 声学通信是一种声学通信.
- 信号处理 信号处理
背景情况:
- 水下声学通信对于遥感和导航至关重要.
- 在盆地规模的距离上传输位置,导航和时间 (PNT) 信息存在重大挑战.
- 在低频率 (75 Hz) 的较长连贯时间使扩展符号传输成为可能.
研究的目的:
- 分析PNT消息的水下声学遥测的通道容量和性能.
- 确定符号错误的经验概率作为信号与噪声比率 (SNR) 的函数.
- 评估用于声通信的低SNR遥测实现.
主要方法:
- 分析了超过1.5年的2700个M序列传输,覆盖了3500公里的距离.
- 使用声学遥测数据计算平均通道容量.
- 解码 10,800 个传输的符号,以确定符号错误与 SNR 的概率.
主要成果:
- 对于盆地级声传输,实现了0.028位/sHz的平均通道容量.
- 低SNR遥测实现的原始比特率为0.1比特/秒,总光谱效率为0.0026比特/秒Hz.
- 经验符号错误概率被确定为不同的SNR水平.
结论:
- 对于水下PNT来说,长时间的低频声传输是可行的.
- 该研究提供了有关声通信系统的性能限制和能力的宝贵数据.
- 结果有助于开发可靠的水下导航和数据传输技术.
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