Print Email Facebook Twitter Cross-correlation beamforming Title Cross-correlation beamforming Author Ruigrok, E.N. (Universiteit Utrecht; Royal Netherlands Meteorological Institute (KNMI)) Gibbons, Steven Wapenaar, C.P.A. (TU Delft Applied Geophysics and Petrophysics) Date 2017 Abstract An areal distribution of sensors can be used for estimating the direction of incoming waves through beamforming. Beamforming may be implemented as a phase-shifting and stacking of data recorded on the different sensors (i.e., conventional beamforming). Alternatively, beamforming can be applied to cross-correlations between the waveforms on the different sensors. We derive a kernel for beamforming cross-correlated data and call it cross-correlation beamforming (CCBF). We point out that CCBF has slightly better resolution and aliasing characteristics than conventional beamforming. When auto-correlations are added to CCBF, the array response functions are the same as for conventional beamforming. We show numerically that CCBF is more resilient to non-coherent noise. Furthermore, we illustrate that with CCBF individual receiver-pairs can be removed to improve mapping to the slowness domain. An additional flexibility of CCBF is that cross-correlations can be time-windowed prior to beamforming, e.g., to remove the directionality of a scattered wavefield. The observations on synthetic data are confirmed with field data from the SPITS array (Svalbard). Both when beamforming an earthquake arrival and when beamforming ambient noise, CCBF focuses more of the energy to a central beam. Overall, the main advantage of CCBF is noise suppression and its flexibility to remove station pairs that deteriorate the signal-related beampower. Subject BeamformingCross-correlationWaveform characterization To reference this document use: http://resolver.tudelft.nl/uuid:fd8655a1-35e5-4fa0-803b-361e98b8d5af DOI https://doi.org/10.1007/s10950-016-9612-6 ISSN 1383-4649 Source Journal of Seismology, 21, 495-508 Part of collection Institutional Repository Document type journal article Rights © 2017 E.N. Ruigrok, Steven Gibbons, C.P.A. Wapenaar Files PDF art_3A10.1007_2Fs10950_01 ... 9612_6.pdf 5.44 MB Close viewer /islandora/object/uuid:fd8655a1-35e5-4fa0-803b-361e98b8d5af/datastream/OBJ/view