两步SVD在极低频电场透地通信中的应用

Application of two-step SVD filter in through-the- earth ELF communications

摘要:

在极低频电场透地通信中，通常同步采集两个互相垂直的电场水平分量。当收发距较大时，采集获得的电场数据往往具有较小的信噪比，接收信号严重受到噪声的干扰，所传递的信息不清晰，甚至错误。因此，当在极低频电场透地通信数据信噪比较低时，需要对其进行滤波处理，压制噪声成分，提高数据的质量。本文提出了一种两步奇异值分解滤波方法，该方法第一步压制极低频电场透地通信数据中较强的噪声，第二步在第一步的基础上继续压制数据中残留的噪声。将该方法应用到漳河水库湖上极低频电场透地通信数据中，处理结果表明，该方法可以有效改善各接收点电场数据的质量，极大地提高了数据的信噪比。

Abstract:

In through the earth ELF communications, we synchronously collect and record two horizontal electric fields perpendicular to each other. When the receiver is far from the transmitter, the signal-to-noise ratio of the ELF data is low, reasonable information cannot be obtained. In this paper, a two-step singular value decomposition (SVD) filter is adopted to reduce noise in the electric fields. The main noise is reduced in the first step, and the residual noise is reduced in the second step. The processing results of measured ELF data indicate that the proposed method can effectively reduce noise and improve the signal-to-noise ratio of the ELF data.