Method for real-time adaptive active noise control, and adaptive active noise control earphones

An adaptive active noise cancellation earphone, comprising:

• a processor;
• a feedforward microphone;
• a feedback microphone;
• a speaker;
• and
• a filter, wherein the filter comprises an Infinite Impulse Response (IIR) filter and a Finite Impulse Response (FIR) filter, and the processor is configured to:
• in a state where active noise cancellation is deactivated, obtain a first transfer function from a feedforward channel to a feedback channel based on a signal collected by the feedforward microphone and a signal collected by the feedback microphone;
• in a state where active noise cancellation is activated, obtain a second transfer function from the speaker to the feedback channel based on the first transfer function and a signal collected by the speaker;
• obtain a characteristic value based on the second transfer function to determine a current wearing state of the earphone based on the characteristic value, and update parameters of the IIR filter according to the current wearing state;
• and
• obtain an updated first parameter of the IIR filter on the feedforward channel and an updated second parameter of the IIR filter on the feedback channel, and update parameters of the FIR filter based on the signal collected by the feedforward microphone, the first transfer function, the first parameter, the second parameter, and the second transfer function.

A non-transitory computer-readable storage medium storing instructions that, when executed by a processor of an earphone, cause the processor to perform operations comprising:

• in a state where active noise cancellation is deactivated, obtaining a first transfer function from a feedforward channel to a feedback channel based on a signal collected by a feedforward microphone and a signal collected by a feedback microphone;
• in a state where active noise cancellation is activated, obtaining a second transfer function from a speaker to the feedback channel based on the first transfer function and a signal collected by the speaker;
• obtaining a characteristic value based on the second transfer function to determine a current wearing state of the earphone based on the characteristic value, and updating parameters of an Infinite Impulse Response (IIR) filter according to the current wearing state;
• and
• obtaining an updated first parameter of the IIR filter on the feedforward channel and an updated second parameter of the IIR filter on the feedback channel, and updating parameters of a Finite Impulse Response (FIR) filter based on the signal collected by the feedforward microphone, the first transfer function, the first parameter, the second parameter, and the second transfer function.