| 摘要 |
FIELD: physics, acoustics.SUBSTANCE: group of inventions relates to acoustics. An audio signal beam forming apparatus comprises a receiving circuit for receiving signals from at least a two-dimensional microphone array, a reference circuit which generates at least three reference beams and a combining circuit which generates an output signal corresponding to the desired beam by combining the reference beams. An estimation circuit generates a direction estimate by determining angles corresponding to local minima for the power metric of the output signal in at least first and second angle intervals, respectively. The direction estimate is generated by selecting one of the angles. The combining circuit determines parameters in order to provide collapse in the angle corresponding to the direction estimate, and minimisation of the directivity cost metric, wherein the directivity cost metric characterises the ratio between gain in the first direction and energy-averaged gain.EFFECT: high efficiency of control and audio quality.15 cl, 8 dwg |
