An array of two biaxial velocity-sensors of non-identical orientation— Their “spatial matched filter” beam-pattern's pointing error

Abstract

A biaxial velocity-sensor (a.k.a. a v-v probe) measures two Cartesian components of an incident acoustical wavefield's particle velocity vector. Such biaxial velocity-sensors are sometimes used as elements in an array. If these elements are not identically oriented, what would happen to the array's “spatial matched filter” beam-pattern? This paper investigates such a beam-pattern's pointing error, for a pair of non-identically oriented biaxial velocity-sensor. This pointing error is investigated here in terms of (i) the biaxial velocity-sensor's misorientation skew angle, (ii) the biaxial velocity-sensor's spatial separation, (iii) the incident signal's wavelength, and (iv) the beamformer's nominal look direction.