Maximum likelihood estimation of the angle of arrival for waves propagating in atmospheric turbulence
Sandra L. Collier, Vladimir E. Ostashev, D. Keith Wilson · The Journal of the Acoustical Society of America · 2007
Physical effects such as refraction from temperature and wind gradients and scattering from atmospheric turbulence can have a significant impact on acoustic beamforming. Many current beamformers only account for the medium effects through use of an effective sound speed. Here we develop a maximum-likelihood estimator (MLE) for the angle of arrival of an acoustic signal that directly accounts for the effects of scattering from atmospheric turbulence. The MLE utilizes a statistical model for the received signal that is based on the theory of wave propagation in a random medium and realistic atmospheric turbulence models. The resulting MLE algorithm is tested using simulated data sets and is found to outperform an estimator that assumes a homogeneous medium.