Self-excitation eliminating method of high gain public address system based on space counteracting

Abstract

The invention discloses a self-excitation eliminating method of a high gain public address system based on space counteracting. Voice signals of amplified frequency components are respectively weighted and then output from a two-path sound box loudspeaker so that two-path output signals mutually cancel out at a microphone. Thus, a microphone loop has extremely high amplification gain by a method of inhibiting the voice output from a sound box from being feeding back to the microphone. On one hand, the method leads the two-path self-excitation signals are voluntarily cancelled out, is dependent of objective signals and does not treat the object signals, and additional inhibition signals are not generated at the same time; and on the other hand, the method cause the signals resulting in squeal to be voluntarily eliminated rather than being filtered from the objective signals, thereby radically solving the self-excitation problem of the microphone.

Description

technical field [0001] The invention relates to a self-excited cancellation method based on space cancellation, in particular to a space-cancelled-based self-excited cancellation method for a high-gain public address system. Background technique [0002] When using a public address system to amplify the sound in real life, the sound source must be close enough to the microphone, otherwise the gain of the microphone needs to be increased. When the gain of the microphone is amplified to a certain extent, the system will howl. This is because as the amplification gain increases, the probability (sensitivity) of the microphone picking up noise increases, and the sound amplified by the loudspeaker returns to the microphone and is amplified again. , thus forming self-excitation, which is howling. [0003] Existing howling suppression methods include random phase compensation technology and power spectrum cancellation technology. [0004] The patent document 1 with the publicatio...

AI Technical Summary

Problems solved by technology

The disadvantage of this is that on the one hand, it weakens the useful signal that you want to amplify, and on the other hand, it essentially solves the self-excitation problem by reducing the system gain, which still limits the amplification gain of the system.

At the same time, Patent Documents 1 and 2 have a common defect in that they all make the feedback audio signal cancel the audio signal itself

The disadvantage of this is that on the one hand, it weakens the useful signal that you want to amplify, and on the other hand, they essentially solve the self-excitation problem by reducing the system gain, so they still limit the amplification gain of the system, and can only suppress the howling but cannot eliminate it. Call

[0008] The feature of Patent Document 3 requires obtaining a power spectrum that includes at least the expanded sound but not the target sound. On the one hand, this feature increases the complexity of the system, and on the other hand, it requires a delay of the speech signal

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