BROADCASTING BANDWIDTH
The secret to Bluetooth is good old-fashioned radio, but not quite as we know it. The main function of radio when used for broadcasting, or when we use it to broadcast mobile phone signals – is distance. After all, a radio station wants to be heard far and wide, while mobile phone signals have to reach the nearest phone tower so they can be relayed to a receiving handset. But Bluetooth is much less powerful than that, with a range of only a few metres. The radio spectrum stretches from 3 Hz to 3,000 GHZ. The lower the frequency, the longer the range, but also the lower the data rate and quality it can support. Bluetooth operates at 2.4 GHZ, which gives it the right balance between range and data quality. The other benefit of this frequency is that it’s available around the world, making it a standard bearer for low-power wireless connectivity.