YouTube channel receives Bluetooth signal at about 13 km
nktbuilds used a 24dBi grid antenna and an nRF54L15 tag to capture 3 data packets over 13 minutes, according to GIGAZINE.
The YouTube channel nktbuilds has reported receiving a Bluetooth Low Energy signal at a distance of about 13 km, surpassing the experiment's 12 km goal. The online outlet GIGAZINE reported the result.
The setup paired a small Bluetooth tag, built around Nordic Semiconductor's nRF54L15 chip, with a large grid antenna with a gain of 24dBi. The antenna was used only for reception. The test relied on BLE Coded PHY, which adds error-checking and recovery information at the cost of a lower data rate.
Calculations before the test suggested reception would be possible at 12 km, and possibly around 70 km in an ideal environment with no obstacles. An early test at 500 m produced a much weaker signal than expected, and adjusting the antenna's direction and height did not fix it; the team suspected ground reflections were interfering with the direct signal. In a later test from a higher location, trees between transmitter and receiver acted as obstacles, and the team used a digital compass to align the antennas.
The captured signal was only 2dB above the minimum detectable level, and a total of 3 data packets were received over 13 minutes. The team attributed the weak signal mainly to obstacles such as trees.
The experiment does not show that Bluetooth can communicate reliably at 13 km. Bluetooth is normally used at ranges of a few metres to a few tens of metres.
Quick answers
How far was the Bluetooth signal received?
About 13 km, exceeding the experiment's 12 km target.
What hardware was used in the test?
A small tag with Nordic Semiconductor's nRF54L15 chip transmitted the signal, and a 24dBi grid antenna was used for reception.
Does this mean Bluetooth works reliably at 13 km?
No. Only 3 data packets were received over 13 minutes, at 2dB above the minimum detectable level, and the result does not show reliable communication at that range.