Local Versus Global Filters

P182 Local Versus Global Filters I. Panea* (Bucharest University) & G.G. Drijkoningen (Delft University of Technology) SUMMARY Array response can be computed directly on the field or later during the pre-processing of fine-sampled digital recordings. In the last case a receiver array acts like a local filter. Its purpose is to attenuate the outof-the-new-spatial-band energy; the size of this spatial-band depends on the size of group interval. Modelling results showed that standard array-forming do not perform a good attenuation of this energy; in this way the array response can be affected by spatial aliasing due to the remaining energy. Better