Spatio-Temporal Gradient Analysis of Differential Microphone Arrays

Practical Aspects of the Calibration of Spherical Microphone Arrays

Spherical microphone arrays have been widely studied for acoustic scene analysis and beamforming. Spatial sound field analysis typically requires two distinct steps: A calibration stage equalizes spatio-temporal deviations of the microphones. Then a decoupling stage extracts orthogonal spatial components of the wave field. For spherical microphone arrays, the decomposition of the measured sound...

Sound Field Recording by Measuring Gradients

Gradient based microphone arrays, the horizontal sound field’s plane wave decomposition, and the corresponding circular harmonics decomposition are reviewed. Further, a general relation between directivity patterns of the horizontal sound field gradients and the circular harmonics of any order is derived. Based on this relation, a number of example differential microphone arrays are analyzed, i...

Spatio-temporal analysis of snow cover in Iran based on topographic characteristics

Spatio-Temporal Changes of Natural Vegetation Disturbance in the Ahle Iman Watershed, Ardabil Province

The present study aimed to assess the spatio-temporal changes in the natural vegetation cover of Ahl Iman watershed, Ardabil province. For this purpose, land use maps of the three years (2000, 2010, and 2020) were extracted from Landsat satellite images. Then, seven landscape metrics (patch density, edge density, patch richness, splitting index, contagion index, Euclidean nearest neighbor dista...

Calibration of Microphone Arrays with Arbitrary Geometries

There is an increasing interest in extracting spatial information from acoustic sound fields, for instance for databased rendering of virtual scenes. Analyzing an acoustic sound field with respect to suitable spatial components, e.g., plane waves, can be performed by evaluating signals captured by a number of spatially distinct microphones, i.e., microphone arrays. Typically, the signal acquisi...