At the end of last year, the Bluetooth Special Interest Group (SIG) announced the launch of Bluetooth 6.0, which introduced a new feature called Bluetooth Channel Sounding (CS). This feature achieves true distance perception by accurately calculating the distance between two devices.
However, the problem was that no Android device on the market supported Bluetooth 6.0 or Bluetooth CS technology at the time. But the latest news shows that Google's newly released Pixel Watch 3 smartwatch has added support for Bluetooth CS.
The first smartwatch to support Bluetooth CS
According to Android Authority, Google Pixel Watch 3 has added Bluetooth CS functionality in the latest Wear OS 5.1 update. After the update, the watch reported support for "FEATURE_BLUETOOTH_LE_CHANNEL_SOUNDING", which is a specific Android feature flag that confirms support for channel detection.
Since Bluetooth CS is a feature of Bluetooth 6.0, this suggests that the Pixel Watch 3 may already support the new standard. Although it has not been officially confirmed, there is speculation that the Pixel Watch 3 has been upgraded to Bluetooth 6.0, making it the first device to achieve a major Bluetooth upgrade via an over-the-air update. Even if this is not the case, it means that Google has found a way to implement Bluetooth CS on Bluetooth 5.3, which is undoubtedly good news for many devices.
In addition, Google has not yet announced a clear timeline for the technology to be put into use in daily applications, but has confirmed that it will be gradually expanded to more products. The Pixel Watch 3 is the first to join Bluetooth CS, indicating that it is ready for future technology upgrades.
Android Authority believes that Google may be waiting for the full launch of Android 16. The new version of the operating system introduces a universal ranging API, which will greatly simplify the calls to tracking technology by applications such as Find Hub. The compatibility requirements of Android 16 clearly stipulate that devices that support Bluetooth CS must "be able to accurately report ranging results within ±0.5 meters with a 90% confidence interval within 1 meter", which sets a reliability bottom line for the tracking experience on different devices.
At present, Pixel Watch 3 users still need to wait for more compatible devices to be released before they can experience the Bluetooth CS function in actual scenarios. As more accessories and Android devices support this technology, users will gradually experience faster and more accurate tracking effects.
Pixel Watch 3 is also equipped with UWB chip
It is worth noting that Google Pixel Watch 3 itself is equipped with a UWB (ultra-wideband) chip. However, since most smartphones, smart watches, and Google Find Hub trackers other than Motorola Moto Tag are not equipped with UWB technology, the UWB function of Pixel Watch 3 cannot be fully utilized for the time being, so the Bluetooth CS function is particularly important.
Previously, most Bluetooth devices have implemented tracking functions based on Bluetooth signal strength, but this method is susceptible to interference, resulting in low tracking accuracy. In contrast, UWB uses high-bandwidth radio waves for positioning, which is more accurate, but requires the installation of specialized and relatively expensive hardware in the tracking device and the tracked device, which significantly increases the cost of the device.
Bluetooth CS is between the two, and determines the distance by calculating the time required for the signal to reflect between two devices, thereby achieving high-precision positioning at the centimeter level. Although its accuracy is slightly lower than UWB, its biggest advantage is that it does not require additional hardware and only requires a Bluetooth connection to work, making it easier to implement and popularize.
Bluetooth CS not only improves positioning accuracy, but also improves the automatic pairing experience of devices within the effective range. For example, users can find nearby trackers faster because the system not only provides sound signals, but also displays the approximate distance to the target object, making the device search process easier and more efficient.
This update shows that Google plans to use Bluetooth CS technology in the future to enable Android trackers to surpass Apple AirTag in positioning accuracy. In addition, according to industry sources, Google is developing a Find Hub app for Wear OS, which will be the first choice for using Bluetooth CS, significantly improving the positioning effect of trackers equipped with Bluetooth 6.0 but lacking UWB capabilities.
This paper is from Ulink Media, Shenzhen, China, the organizer of IOTE EXPO (IoT Expo in China)
