Adaptive Multi-Cone Spatial Constriction of the Search Space of a Wireless Sensing Network of Tri-Axial Velocity Sensors to Mitigate Innumerable “Image Sources” in Air-Acoustic Source Localization

An acoustic wireless sensing network affronts environmental reverberations engendering spurious “image sources,” which can confuse the sensors. Against such “image sources,” this paper advances an acoustic source-localization algorithm adaptively constricting the warranted spatial domain in search for the physical source, thereby simplifying real-time computation. Furthermore, acoustic wireless sensing is complicated by sound's arbitrarily ultrawide frequency bands over arbitrarily transient durations, and the sound source could be positioned anywhere near or far from any sensing node. Such difficult-to-handle time–frequency unknown irregularities are mitigated (with computational simplicity) by this proposed scheme, which populates each sensing node with a tri-axial velocity sensor, whose array manifold is advantageously invariant of time, frequency, and range. This proposed scheme needs no prior information on the reverberant environment's space–time impulse response, no prior information on the physical source's frequency spectrum nor time–frequency signal structure. This computationally efficient scheme also bypasses any computationally burdensome pre- or post-processing procedures, such as frequency sub-banding, or temporal correlation filtering.