1. A sensor array comprising: a plurality of ultra wideband (UWB) sensors, said plurality of UWB sensors arranged in a sparse array, a first UWB sensor of said plurality of UWB sensors being configured to transmit first UWB signals, a second UWB sensor of said plurality of UWB sensors being configured to receive first signal returns of said transmitted first UWB signals reflecting off an object, said first signal returns corresponding to first forward scattering data; and a processor in communication with at least one of said plurality of UWB sensors, wherein said processor determines at least one characteristic of said object based on said first forward scattering data and uses said at least one characteristic and at least one established criteria to determine an alert condition.