| 摘要: |
| 在无线传感器网络的应用中,位置信息对于监测活动起着极其重要的作用.TDOA(time difference of arrival)是一种得到广泛应用的定位方案,但是对于传统的TDOA算法,使用者需要预先通过在节点间收发数据包执行所有节点的时间同步,这不仅增加了额外的成本,还会因为软件和硬件的延迟带来一些计时误差,这些误差虽然绝对数值较小,但仍然会极大地降低高速信号定位的精度.提出一种新的TDOA定位方法,在需定位的信号源之外添加了一个位置已知并固定的系统信号源来改变TODA值的计算方式,让这个系统信号源在待定位物体发出源信号S之后发出一个与源信号相同的信号S′,然后再使用同一节点接收两个不同的信号S和S′的时间差(time difference of 2 signals,简称TD2S)来计算两个不同节点接收S的时间差,消除了TDOA方法对节点间时间同步的依赖,进而有效地提高了声源的定位精度.最后,在手机上实现了该定位方法,并在三维空间下进行了实验,结果表明,所提方法不仅定位精度较高,而且是一种容易部署、成本低、抗干扰能力较强的方法. |
| 关键词: 声音信号 定位 时间同步 移动设备 |
| DOI： |
| 分类号: |
| 基金项目:国家自然科学基金(60803124,61170212) |
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| Acoustic Source Localization Scheme without Time Synchronization |
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YU Ran, XU Bin, SUN Guo-Dong
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Department of Computer Science and Technology, Tsinghua University, Beijing 100084, China
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| Abstract: |
| Location is of great importance wireless sensor network applications because location information can often be used to identify events.TODA is a typical localization scheme widely used in previous work,but it requires time synchronization over all anchor nodes with known positions.Time synchronization increases the cost and complexity of system,and the errors caused by software and hardware seem subtle but often lead to bad accuracy of localization.A new TDOA localization scheme is presented in this paper,whose basic idea is to use an additional, position-known signal source,S′to change the way of calculating TODA values.After the emission of the source signal S,the new signal S′is emitted.The TDOA of S between different receivers can be derived from the time difference of receiving S and S′,called TD2S,at each receiver.This way eliminates the dependence of TODA on time synchronization,and improves the localization accuracy.Experiments under three-dimensional space have been conducted with mobile phones,and the results show that the proposed scheme is not only of high accuracy,but also of easy deployment,low cost,and robustness. |
| Key words: acoustic signal localization time synchronization mobile device |
