Abstract: A method and system is described for reducing unwanted noise components/interfering targets detected through an ambiguous beam-steer direction, such as the ambiguous ‘back-lobe’ of a sensor array. A pressure sensor array 52 and a plurality of pressure gradient sub-arrays 541-N are beamformed individually at processing stages 56, 581-N to derive signals indicative of directional responses, one from each group or sub-group. The signals are scaled and weighted (60, 620-N) and processed to define a cardioid beam with nulls pointing in the ambiguous beam-steer direction.

Abstract: A method and system is described for reducing unwanted noise components/interfering targets detected through an ambiguous beam-steer direction, such as the ambiguous ‘back-lobe’ of a sensor array. A pressure sensor array 52 and a plurality of pressure gradient sub-arrays 541-N are beamformed individually at processing stages 56, 581-N to derive signals indicative of directional responses, one from each group or sub-group. The signals are scaled and weighted (60, 620-N) and processed to define a cardioid beam with nulls pointing in the ambiguous beam-steer direction.

Abstract: The invention relates to a method of analyzing signals from an array of sensors, the array including one or more pressure sensor and one or more pressure-gradient sensor. The method includes combining data received from one or more pressure sensors and data from one or more of the pressure-gradient sensors, in such a way as substantially to eliminate noise components from the product. The invention also relates to a sonar system and an array configuration for implementing the method, as well as a computer readable product, storage device storing the computer readable product and computer receivable signal for implementing the method.