Bluetooth 5 is the latest version of the Bluetooth specification. With major new features such as long range and high throughput modes it represents one of the biggest advancements in the Bluetooth specification.
The Bluetooth 5 specification will undergo ratification in early December. Visit here for more information on Bluetooth 5 from December 12th 2016.
Major new features of Bluetooth 5
- Higher datarate (x 2)
- Long range (x 4)
- Increased broadcast capability (x 8)
Bluetooth low energy is now potentially capable of up to 4 times the range it had previously. The longer range is achieved by scaling down the data rate in discrete steps. Bluetooth low energy now has the following data rate options
- 2Mbs (High throughput mode)
- 500kbs (long range mode)
- 125kbs (long range mode)
Higher data throughput
The data rate for Bluetooth low energy has now been extended from a singular transmission speed (1Mbs) to four discrete data rate speeds as seen in the list above. The maximum speed is doubled to 2Mbs. Together with advancements introduced in Bluetooth 4.2 which allowed for Data Length Extensions (DLE) overall throughput is x5 higher than the original Bluetooth 4.0 level. Now net data throughput not including overhead such as addressing can be as high as 1.4Mbs. Data packet size, datarate and overall data throughput are illustrated in fig. 1.
Fig. 1 Bluetooth 5 data packet size/throughput chart
This increase offers opportunities for new applications that simply need more data throughput than was possible previously. It also enables much faster Over the Air Device Firmware Upgrades (OTA-DFU).The nRF52840, like all members of the nRF5x series Socks is a flash-based SoC thus enabling it to take advantage of this increased speed to perform firmware updates and for uploading data in bulk fashion.
Increased broadcasting capacity
Advertising extensions are introduced to alleviate advertising channel occupancy and potential channel congestion. Data Length Extensions and a new PHY layer means longer packet lengths in terms of actual data and the length of time they occupy a channel. As only 3 advertising channels exist these channels could soon become congested with advertising packets with large data payloads at lower on-air transmission speeds such as 125kbs.Advertising extensions mitigates this potential issue by advertising on the 3 advertising channels as previously, but the data to be sent is on an agreed non-advertising channel.
Fig. 2 Advertising extensions allocation of channel for advertising data
An additional feature of Advertising extensions is the ability to chain advertising packets to create extended advertising data payloads seen in fig. 3
Fig. 3 Advertising extensions ‘chaining’ of advertising data packets
Periodic advertising allows for more synchronized broadcasting of data between devices. In this mode periodic advertising happens at a deterministic periodic interval thus allowing true connectionless broadcasting.
nRF52840 and nRF52832 Bluetooth 5-ready SoCs
The nRF52840 and nRF52832 multi-protocol SoCs has been designed to take advantage of these significant performance advancements of Bluetooth 5. Additionally, the nRF52840 has improved output power of 8dB which together with new long range features in Bluetooth 5 offer significant new application possibilities requiring longer range communication.
nRF52840/nRF52832 Bluetooth 5 feature support
|Bluetooth 5 features||nRF52840||nRF52832|
|Increased broadcast capacity||X||X|
|nRF52840||Multi-protocol Bluetooth 5, Bluetooth low energy, ANT, 802.15.4, 2.4GHz RF SoC|
|nRF52832||Multi-protocol Bluetooth low energy/ANT/2.4GHz SoC|
|nRF52840 Preview DK||Development kit for nRF52840 SoC|
|S140||Bluetooth 5 protocol stack for nRF52840|
|S132||Bluetooth 4.2 protocol stack for nRF52840|
|nRF5 SDK||Software Development Kit for nRF51 and nRF52 Series|