Depending on the maximum power capacity of Bluetooth, the range can be anywhere from 1 meter to 100 meters or more.
The Bluetooth core specification specifies a minimum range, but technically the range is application specific and unlimited. Manufacturers can tailor the range to actual use cases.
Connecting two Class 1 devices with high sensitivity and transmit power can result in a range well above the typical 100m, depending on the throughput required by the application. Some devices are capable of ranges of up to 1km or more in open environments.
Bluetooth is a standard wireless communication protocol based on a device's low-cost transceiver chip with a short range and low power consumption. Since devices use radio (broadcast) communication systems, they are not connected by physically visible wires, however a quasi-optical wireless path must be feasible. The range is power and category dependent, but the effective range varies from application to application.
Expanded:
Effective range depends on transmission conditions. p>Effective range is related to transmission conditions, material coverage, variations in production samples, antenna configuration, and battery status. Most Bluetooth applications are designed for indoor environments where signal degradation due to wall attenuation and signal reflection can make the range much less than the range specified by the Bluetooth product.
Class A is used in high-power/long-range Bluetooth products, but because of the high cost and high power consumption, it is not suitable for personal communication products (cell phone/Bluetooth headset/Bluetooth Dongle, etc.), so it is mostly used in some commercial special purpose applications, and the communication distance is about 80~100M range.
Class B is currently the most popular system, the communication distance of about 8~30M between (usually usually about 10 meters), it seems that the design of the product depends on, mostly used in cell phones / Bluetooth headset / Bluetooth Dongle personal communication products, power consumption and the size of the smaller, easy to carry.
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