The acoustic vector sensor (AVS) can measure the acoustic pressure fieldââ?¬â?¢s spatial gradient, so it has directionality. But its channels\nmay have nonideal gain/phase responses, which will severely degrade its performance in finding source direction. To solve this\nproblem, in this study, a self-calibration algorithm based on all-phase FFT spectrum analysis is proposed. This method is ââ?¬Å?selfcalibratedââ?¬Â\nbecause prior knowledge of the training signalââ?¬â?¢s arrival angle is not required. By measuring signals from different\ndirections, the initial phase can be achieved by taking the all-phase FFT transform to each channel. We use the amplitude of the\nmain spectrum peak of every channel in different direction to formulate an equation; the amplitude gain estimates can be achieved\nby solving this equation. In order to get better estimation accuracy, bearing difference of different training signals should be larger\nthan a threshold, which is related to SNR. Finally, the reference signalââ?¬â?¢s direction of arrival can be estimated. This method is easy to\nimplement and has advantage in accuracy and antinoise. The efficacy of this proposed scheme is verified with simulation results.
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