A Triad of Cardioid Sensors in Orthogonal Orientation and Spatial Collocation-Its Spatial-Matched-Filter-Type Beam-Pattern

This paper proposes a new configuration of acoustic sensors-the collocation of three cardioid sensors in perpendicular orientation, in order to increase the mainlobe-to-sidelobe height ratio (possibly to 8). This paper will analyze such a proposed triad's spatial matched filter beam-pattern that is independent of the frequency/spectrum of the incident signals. Specifically, this paper will analytically derive the mainlobe's pointing error in azimuth-elevation, the mainlobe's two-dimensional beam width, the necessary and sufficient conditions for a sidelobe to exist, the mainlobe-to-sidelobe height ratio, and the array gain. These above characteristics depend on the cardioids' cardiodicity parameter and on the beam's nominal look direction.