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arXiv 0903.4426cs.ITmath.IT
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水下网络的容量缩放定律

Capacity Scaling Laws for Underwater Networks

Daniel E. Lucani, Muriel Médard, Milica Stojanovic

摘要:

水声信道的特征在于路径损耗,其不仅取决于传输距离,而且取决于信号频率。在距离$l$上从一个用户传输到另一个用户的信号经受$l^{-α}{a(f)}^{-l}$的功率损耗。虽然陆地无线电信道可以类似地建模,但是水下声学信道具有不同的特性。与传播的几何形状相关的扩频因子$α$具有在$1 \leq α\leq 2$范围内的值。吸收系数$a(f)$是频率的快速增加函数:它在100 kHz时比在几Hz时大三个数量级。无线网络容量的现有结果对应于$a(f) = 1$或大于1的常数和$α\geq 2$的情况。这些结果不能应用于水声网络中的衰减变化的系统带宽。我们使用注水参数来评估最小传输功率和最佳传输带宽作为链路距离和期望数据率的函数,并研究在此模型下的容量缩放定律。

英文摘要:

The underwater acoustic channel is characterized by a path loss that depends not only on the transmission distance, but also on the signal frequency. Signals transmitted from one user to another over a distance $l$ are subject to a power loss of $l^{-α}{a(f)}^{-l}$. Although a terrestrial radio channel can be modeled similarly, the underwater acoustic channel has different characteristics. The spreading factor $α$, related to the geometry of propagation, has values in the range $1 \leq α\leq 2$. The absorption coefficient $a(f)$ is a rapidly increasing function of frequency: it is three orders of magnitude greater at 100 kHz than at a few Hz. Existing results for capacity of wireless networks correspond to scenarios for which $a(f) = 1$, or a constant greater than one, and $α\geq 2$. These results cannot be applied to underwater acoustic networks in which the attenuation varies over the system bandwidth. We use a water-filling argument to assess the minimum transmission power and optimum transmission band as functions of the link distance and desired data rate, and study the capacity scaling laws under this model.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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