As the premise of low latency and high fidelity of TWS bluetooth headsets, connection stability is of vital importance, especially in today's complex electromagnetic environment, which will interfere with the connection of TWS headsets.At the same time, many of today's TWS bluetooth headsets also have the function of voice calling. In the future, they may also provide voice assistant and other functions. The addition of these functions also puts forward more stringent requirements on the chip of TWS bluetooth headsets.

As for how to have good anti-interference performance in today's complex electromagnetic environment, Mr Liu said: 'we can filter out a lot of messy signals through internal analog filters, digital filters and so on.At the same time, we use demodulation threshold expansion technology, etc., to improve the receiving sensitivity of the chip.

Wang long believes that ziguang zhanrui has certain advantages in this aspect. Because it has accumulated a lot of technologies in the field of mobile phones, and the internal environment of mobile phones is very noisy, including interference from various signal sources such as bluetooth and WiFi, it has a deep accumulation of how to deal with interference.Because 2.4g is a very noisy frequency band, all kinds of devices communicate in it.In the mobile phone industry, how to deal with the interference in the 2.4g band is very important. We have accumulated the technology on the phone and applied it to the earphones, so we can perform very well in noisy environment.

'Most audio codecs on the market today are static in nature and only support fixed bit rates, so in a challenging rf environment they can cause problems with wireless connections,' liu said.Qualcomm aptX Adaptive can dynamically adjust code rate and performance according to its environment.Typically, the technology supports speeds from 279Kbps to 420Kbps.When there is significant rf interference in the environment, the aptX Adaptive codec can be dynamically adjusted to adopt more stable and low bit rate audio transmission but still achieve audio quality close to CD.

At the same time, as the TWS bluetooth headset is often used outdoors, it is inevitable to encounter a lot of environmental noise, which will bring some interference to the users who use the TWS bluetooth headset to talk.'Now we have a mature algorithm for echo cancellation and noise reduction,' Mr Liu says.At the same time, we have independently developed a set of voice enhancement algorithm, which can effectively improve the quality of human voice, improve the hearing sense of human voice, and make it easier for voice assistants to recognize.'

Purple light show sharp, hope that through integration to solve the environmental problems related to noise, king Long said: 'at present, we have the systematic aspects to solve the problem of environmental noise and speech recognition, the future we hope to be able to the speech recognition chip, environmental noise processing units such as integrated on a chip, but not only rely on systematic to solve.'

Regarding noise reduction of environmental sound, liu junyong said: 'Qualcomm has invested many years in bluetooth headset, and has launched the eighth generation of Qualcomm CVC noise reduction technology. The combination of CVC noise reduction algorithm and low-power voice wake-up technology can accurately pick up users' voice in noisy environment.Qualcomm CVC noise reduction technology supports the elimination of background noise and echo suppression, including support for dual-mac noise reduction, when the user and the other side of the call, the CVC noise reduction technology enables clear voice communication.

Currently, there are many TWS bluetooth headphone chips on the market. For buyers, in addition to performance, the most important thing is cost performance.Wang said: 'purple light is already investing in three-in-one and four-in-one chips, but the more integrated they are, the more complex they will be and the more expensive they will be.Therefore, we need it to have excellent performance, strong anti-interference, and a very competitive price, which can also make our products have certain advantages in cost performance.In the future, unigroup zhangrui will not pursue a price war alone, but a reasonable balance of performance, power consumption and price.

We have our own solution for the cost of TWS bluetooth headphone chip. Liu zhuzhan thinks: 'common costs are divided into internal cost, external cost and development cost.Inside the chip, we optimize the size of each module unit from the IC level and the size of RAM and ROM from the software level.At the same time, we are highly integrated, and constantly reduce IC circuit components.At the application level, constantly improve the SDK function, realize the visual configuration development of customers, effectively shorten the development time and control the development cost.

In terms of cost, qualcomm also helps customers save the cost of product research and development through its own solutions. In 2018, it launched three series of products -- QCC302X, QCC303X and QCC5100 -- for the audio and audio market.All three series of products are single-chip designs, i.e., one chip integrated with bluetooth transceiver, application processor, DSP, audio codec and charging module, which not only reduces the development time of the manufacturer, but also effectively reduces the cost.

'In particular, the QCC5100 platform integrates dedicated hardware modules to support hybrid active noise reduction (ANC), which reduces the complexity and cost of adding active noise reduction chips to audio devices such as earplugs,' liu said.This will help manufacturers reduce the development time required to achieve a top-level audio experience in smaller device form designs.In addition, by combining local speech recognition algorithms running on bluetooth audio SoC with mobile applications and cloud services, the development of QCC5100 series for voice assistant products can help customers reduce product development time and cost.On the ecological side, if you can support Qualcomm aptX technology for lower-priced products, the overall sound quality will be improved.This is added value to the product.If the product supports aptX technology at the same price level, the sound quality will be better, so it is closely related to the expectation of the user when buying the product.'

In terms of connection stability and anti-interference of TWS bluetooth headphone, speech recognition chip and noise reduction processing unit can be integrated into a single chip, or stable connection and strong anti-interference ability can be achieved through noise reduction algorithm and powerful encoder.Meanwhile, within the chip, the size of each module is optimized from the IC level, the size of RAM and ROM is optimized from the software, the SDK function is improved on the application level, and the r&d time is shortened, which can effectively reduce the chip cost.Achieve the best balance in chip power consumption, performance and cost without reducing chip performance.