What is Bluetooth-5

 Bluetooth Special Interest Group (Bluetooth SIG) announced Bluetooth- 5. 

Today Bluetooth comes in two flavors, “Classic” and “Low Energy.” The former is the Bluetooth that enables our wireless keyboards and mice, along with wireless headsets and speakers. The latter, Bluetooth Low Energy (BLE) uses a lot less power and is designed for areas like healthcare, fitness and beacons. So, wearables like the FitBit use BLE rather than Bluetooth Classic.

Last month, the Bluetooth Special Interest Group (Bluetooth SIG) announced Bluetooth 5. Unlike former iterations of the Bluetooth specification this one doesn’t come with a “.0” (dot zero) ending, but is just known as 5. But there is more to Bluetooth 5 then just the naming convention. In terms of Bluetooth Classic, Bluetooth 5 remains exactly the same as previous versions of Bluetooth. So all your existing keyboards and wireless speakers will continue to work. However the real changes are for Bluetooth Low Energy.

Depending on who you talk to, Bluetooth 4.x BLE had a range of between 50m to 100m, outdoors – in line of sight. Indoors that is probably reduced to somewhere around 10m to 20m. Bluetooth 5 will quadruple the range of Low Energy devices. Using the more conservative figures, that will mean 200m outdoors (up from 50m) and around 40m indoors. If it manages to work at 40m indoors (that is some 131 feet) then there is lots of potential for home automation using just Bluetooth 5.

Bluetooth 4.x BLE can transfer data at 1Mbps, Bluetooth 5 BLE doubles that to 2Mbps. In practical terms that means that future wearables will sync twice as fast. However it also means that there is potential for newer types of BLE devices, that need high throughput speeds. Like the range numbers given above, the 2Mbps is a theoretical speed and once you factor in things like the protocol overheads then the actual throughput is somewhere around 1.6Mbps and that is full duplex, so from a Bluetooth 5 compatible wearable (or whatever) to a Bluetooth 5 enabled smartphone would actually be just 783Kbps.

 This is where Bluetooth 5 comes in. The size of the broadcasting capacity is increasing from 31 bytes to 255 bytes.

With more speed and more range it sounds like Bluetooth 5 will take more power. But thanks to some clever changes in the way the signals are modulated and by improving the use of the frequency spectrum, Bluetooth 5 will actually use less power, in some cases up to 2.5 times less power!

As well as gains in performance and speed, Bluetooth 5 has also improved its connection-less advertising capabilities. In Bluetooth 4.x BLE this capability was designed for Bluetooth Beacons, however the payload of an advertising packet was limited to 31 bytes. This presents several limitations.

It is worth noting that Bluetooth SIG don’t define the structure of what goes inside these advertising packets, the message format. This means that any additional protocol about the type of data inside the packet needs to be included in that 31 bytes. Typically this data can take up to 10 or more bytes, which reduces the actual data space to less than 21 bytes.