Bearing accuracy and resolution bounds of high-resolution beamformers

The paper compares the performance of two high-resolution beamformers, MUSIC and Modal Decomposition, to that of the Conventional Beamformer, under the constraints of small signal-to-noise ratio(SNR) and short observation times. In particular, the reliability of the methods in estimating and resolving the bearings of plane waves with a linear array is examined by way of simulation. The presence of a threshold SNR below which bearing estimates rapidly degrade is shown to increase by 2-3 dB for the high-resolution methods, although the threshold is relatively insensitive to an overestimation of model order.