How Does TWS Headset Achieve Active Noise Reduction?

The full English name of TWS is True Wireless Stereo. Stereo is the biggest difference between it and the previous Bluetooth headsets.

After Apple launched the first generation of Airpods in 2016, it quickly became one of the most popular Apple products.

Driven by AirPods, more and more people have begun to pay attention to TWS headsets, and their popularity is getting higher and higher. Coupled with the gradual conquering of binaural connection, battery life, and noise reduction capabilities in the TWS headset industry, TWS headsets have ushered in a period of accelerated development.

The current TWS headset has basically solved the problem of connection stability and power consumption. How to ensure the quality of the call when the noise is too large or the signal is not good has become a key factor to improve the user experience.

There are three main types of active noise reduction technologies in the current TWS headset market, ANC (Active Noise Control, active noise reduction); ENC (Environmental Noise Cancellation, environmental noise reduction technology); and AI call noise reduction technology.

Among them, the working principle of ANC noise reduction is to collect external environmental noise through the microphone. The system transforms an inverted sound wave and adds it to the speaker according to the collected noise. The final sound heard by the human ear is environmental noise + inverted environmental noise, The two kinds of noise are superimposed to achieve sensory noise reduction. It can be divided into feedforward active noise reduction and feedback active noise reduction, and hybrid active noise reduction. However, feedback type active noise reduction can easily cause howling.

ENC uses a dual-microphone array to accurately calculate the direction of the caller's speech, which protects the target voice in the main direction while removing various interference noises in the environment. ENC technology can effectively suppress 90% of the reverse environmental noise, thereby reducing the environmental noise up to 35dB or more.

It is said that AirPods Pro adopts ENC technology in addition to ANC technology. Another product that uses ENC technology is Google's Pixel Buds. They all adopted the ST program.

However, this scheme has a disadvantage that it requires a relatively large algorithm development work, which will also increase the power consumption of the entire system.

AI call noise reduction technology is a single microphone call noise reduction solution proposed by Elephant Sound in 2018. It combines the Computational Auditory Scene Analysis Theory (CASA) with deep learning technology to separate human voice and background noise in real-time. Extract clear human voice from environmental noise.

The above information is provided by the wireless earphones supplier.