Using array processing to isolate seismic signals from noise and interferers of cultural origin

This paper examines the use of arrays of seismic sensors to enhance signals where multiple sources and an inhomogeneous medium complicate the received signal. Array processing is useful because it offers the opportunity to enhance SNR of the target signal while attenuating noise sources via spatiotemporal filtering. We used an adaptive beamforming algorithm to isolate the particular signal of interest from ambient noise and an interferer. The unpredictable nature of the noise and interferer environment was addressed by having the beamformer adapt to the environment. We present the results of using the beamformer on data from a thirty-geophone array. Initial results indicate inhomogeneities in the vacinity of the seismic sensors caused the significant perturbations to the wavefront. The adaptive algorithm was able to compensate for this and thereby performed better than the traditional delay-and-sum algorithm at isolating the target signal from the interfering signals.