Bandwidth Performance of Linearly Constrained Minimum Variance Beamformers

The bandwidth performance of a linearly constrained minimum variance (LCMV) beamformer with and without tapped delay-lines (TDLs) processing is examined. A narrowband beamformer (without TDLs) is able to suppress wideband signals, but with the cost of a large number of sensors. As a solution to this problem, TDLs are introduced, which leads to the well-known wideband beamforming structure. It is shown how the SINR (signal to interference plus noise ratio) improves for different signal bandwidths with an increasing number of sensors for the narrowband structure, and by changing the length of the TDLs for the wideband structure