Active noise reduction system and method for eliminating noise floor interference

Abstract

The invention provides an active noise reduction system for eliminating noise floor interference, which comprises at least one noise reduction channel. The noise reduction channel comprises a microphone, an AD converter, a noise reduction filter and a DA converter, wherein a programmable gain amplifier is connected between the microphone and the AD converter for adjusting an input signal of the microphone; a first dynamic range expansion module is connected between the AD converter and the noise reduction filter for expanding the dynamic range of the AD converter; a second dynamic range expansion module is connected between the noise reduction filter and the DA converter for expanding the dynamic range of the DA converter. The active noise reduction system for eliminating noise floor interference in the invention expands the dynamic range of the AD converter and the DA converter and reduces the noise floor of the noise reduction headset.

Description

technical field [0001] The invention relates to the technical field of signal processing, in particular to an active noise reduction system and method for eliminating background noise interference. Background technique [0002] Active noise-canceling headphones are gradually coming into people's lives, allowing people to get a relatively quiet environment in a noisy environment. The principle is to cancel the sound wave (feedforward) or add a feedback acoustic path (feedback) to the sound path to reduce the noise heard by the ear by actively sending out sound waves with opposite phases through the earphones. [0003] In the existing active noise reduction scheme, it is easily affected by external low-frequency noise, resulting in "popping" and "popping" sounds. Simple active noise reduction headphones will affect people's reception of external voice and other signals, causing inconvenience to people on specific occasions, and active noise reduction can easily eliminate low-...

AI Technical Summary

Problems solved by technology

[0003] In the existing active noise reduction scheme, it is easily affected by external low-frequency noise, resulting in "popping" and "popping" sounds

Simple active noise reduction headphones will affect people's reception of external voice and other signals, causing inconvenience to people on specific occasions, and active noise reduction can easily eliminate low-frequency components of music when playing music, reducing the weight of music playback

Moreover, the active noise reduction earphones that adopt digital signal processing in the prior art, due to the limited dynamic range of AD converters and DA converters, are prone to produce "hissing" background noise, or are prone to "popping", "popping", etc. "Noise, it is difficult to achieve effective noise reduction effect

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