Applications of beamforming and acoustic holography in an anechoic tank with surface reflections

Recently, our institute, KRISO/KORDI, constructed a small anechoic tank which has an anechoic lining at the four walls and bottom. Because surface reflections still occur, special care must be taken for acoustic measurements and array signal processing, for example, source localization and acoustic holography. In this paper the effects of the surface reflections to the array signal processing methods are investigated. First, estimated errors by both methods are analyzed for various measurement parameters. Beamforming experiments with vertical line arrays are performed. Holographic reconstruction of simple and complex acoustic sources is also performed to compare the true and estimated results.