A higher-order “figure-8” sensor and an isotropic sensor—For azimuth-elevation bivariate direction finding

Abstract

A "p-u probe" (also known as a "p-v probe") comprises one pressure-sensor (which is isotropic) and one uni-axial particle-velocity sensor (which has a "figure-8" bi-directional spatial directivity). This p-u probe may be generalized, by allowing the figure-8 bi-directional sensor to have a higher order of directivity. This higher-order p-u probe has not previously been investigated anywhere in the open literature (to the best knowledge of the present authors). For such a sensing system, this paper is first (1) to develop closed-form eigen-based signal-processing algorithms for azimuth-elevation direction finding; (2) to analytically derive the associated Cramér-Rao lower bounds (CRB), which are expressed explicitly in terms of the two constituent sensors' spatial geometry and in terms of the figure-8 sensor's directivity order; (3) to verify (via Monte Carlo simulations) the proposed direction-of-arrival estimators' efficacy and closeness to the respective CRB. Here, the higher-order p-u probe's two constituent sensors may be spatially displaced.

Quantitative Analysis Method and Correction Algorithm Based on Directivity Beam Pattern for Mismatches between Sensitive Units of Acoustic Dyadic Sensors

“…According to the Taylor series expansion theory of sound pressure [4], complete sound field information includes sound pressure (scalar, zero-order spatial partial derivative), sound pressure gradient or acoustic particle velocity (vector, first-order spatial partial derivative), second-order sound pressure gradient or particle velocity gradient (dyadic, second-order spatial partial derivative) and higher order information. Additionally, the higher the order of the measured sound field information, the higher the directivity of the acoustic detection system [5][6][7][8][9][10][11], so as to meet the application requirements.…”

A study on MEMS vector hydrophone and its orientation algorithm

“…Hui Junying et al have studied the combined signal processing of acoustic pressure and velocity (Hui et al, 2000;Yao et al, 2006), which realized the effective suppression of coherent interference. The target direction of arrival (DOA) estimation method based on acoustic intensity estimator has high positioning accuracy, as discussed in Muaz et al (2018), Wenbo (2013) and Yang et al (2015). A comparison of different techniques in estimating the azimuth angle of a source is investigated in Zhao et al (2018).…”