3D Angle-of-Arrival Positioning Using von Mises-Fisher Distribution

We propose modeling an angle-of-arrival (AOA) positioning measurement as a 3-dimensional von Mises-Fisher (VMF)-distributed unit vector instead of the conventional normally distributed azimuth and elevation measurements. Describing the 2-dimensional AOA measurement with three numbers removes discontinuities and reduces nonlinearity at the poles of the azimuth-elevation coordinate system. Our computer simulations show that the proposed VMF measurement noise model based approximative Bayesian filters outperform the normal distribution based algorithms in accuracy in a scenario where close-to-pole measurements occur frequently.