An ultrasound controller unit (22) for controlling an ultrasound transducer unit (24) in acquiring ultrasound data for the purpose of deriving one or more physiological parameter measurements. The controller is adapted to control weighting coefficients applied to transmit and receive signals of each of a plurality of transducer elements (26) of the transducer unit. The controller is adapted to detect any artifact in received data affecting (e.g. obscuring) the output path of one or more of the transducers, and to identify the affected transducer elements. The weighting coefficients of the non-affected transducer elements are then adjusted so as to minimize an estimated noise component in the parameter measurement, if derived using only the non-affected transducer elements. Measurements of the one or more parameters are then derived by collecting data from the non-affected transducers only, these being configured with the optimized weighting coefficients.
