bluetooth® Bluetooth Technology Tip

Bluetooth bluetooth® technology is widely used in a variety of devices, and will continue to play a key role in the IoT world of IoT. Here are some tips on Bluetooth technology to prepare for reference.

Bluetooth bluetooth® Technology was founded in 1994 with the name of a Danish king Harold Bluetoothin 10th century, who unified the current Norwegian, Swedish and Danish regions, Named after him is also a means of connecting the various discrete devices that are now available. So bluetooth® Bluetooth and "blue teeth" doesn't matter: Bluetooth technology currently has several versions in parallel, Bluetooth 2.1 (Bluetooth BS/EDR), 3.0 (Bluetooth HS) and 4.0 (Bluetooth Smart or BLE).

The most common Bluetooth device may be a Bluetooth headset that can play high-quality music from your phone without a connection. This is typically done with the Bluetooth2.1 Br/edr (Basic rate/enhanced data rate), which is specifically optimized for high-quality data streams with stable transmission.

bluetooth® 3.0 Bluetooth Hi Speed technology can be used for high data transmission, such as transferring large audio or video files between devices, downloading photos in bulk, and so on.

The recent comparison of the fire is Bluetooth 4.0, that is, Bluetooth low energy (BLE, or Bluetooth Smart), Bluetooth 4.0 (BLE) has been mainly in the lower power to make it possible to apply to wearable devices such as power inconvenient scenes, using BLE, A regular button battery can last for months or even a year. This will also enable Bluetooth BLE technology to do a IoT of IoT. It is conceivable that in the near future you will be surrounded by a multitude of interconnected smart devices, smart watches, heart rate monitors, smart locks, smart socks, sneakers, smart chopsticks and more. Everything around you is likely to be connected to your phone or Bluetooth Smart Gateway via low-power blue technology to further connect to the Internet.

It is generally believed that Bluetooth is only suitable for short-distance transmissions. But in fact, Bluetooth technology can be used for long-distance transmission. Our common mobile phones, headphones, speakers and other Bluetooth equipment transmission distance generally not more than 10 meters, but this does not mean that Bluetooth technology itself can only be used for short-distance transmission. As Bluetooth and WiFi are applied to the 2.4GHz frequency, the transmission distance is as much as 802.11b up to hundred meters. As shown in the table below, some Class 1 devices, due to the relatively high power consumption, can be transferred to a range of 100 meters if there is a steady supply of sufficient power. And our common mobile phones, headphones and other equipment due to power constraints, generally belong to Class 2, transmission distance is generally within 10 meters.

Device Class	Transmit Power	Intended Range
class 3	1 MW	less than meters
class 2	2.5 MW	10 meters, Feet
class 1	100 MW	100 meters, 328 feet

Bluetooth and WiFi are running at 2.4GHz frequency, the antenna applied to the WiFi can also be used for Bluetooth devices, by welding an antenna to Bluetooth and supported by a stable power supply, it is possible to achieve long-distance transmission. For example, the following improvements Linksys USBBT100

However, Linksys USBBT100 has a version of its own antenna on Amazon, the transmission distance of up to 100 meters, can connect 7 devices at the same time, costs about 50 knives.

Thanks to Joshua Wright.

bluetooth® Bluetooth Technology Tip