A simple adaptive cardioid direction finding algorithm

A simple adaptive cardioid direction-finder algorithm using signals from closely spaced omnidirectional microphones is described. One implementation utilizes a computationally simple constrained LMS adaptive filter with only 3-taps for the general 3D case and 2-taps for the 2D case. The solution adaptively finds the location of the single cardioid null that minimizes the output power of a generally 2D or 3D rotated cardioid.