SAN JOSE, Calif. — The Bluetooth Special Interest Group officially ratified its version 5, which includes a modular set of optional extensions for throughput, range, and other features. Chip makers, including Cypress and Nordic, are already sampling parts supporting the specs that do not include mesh networking, a piece delayed until mid-2017.
The specs define a new modulation scheme for throughput up to 2 Mbits/second. A new forward error correction technique can quadruple range to an estimated 120 meters, albeit at significantly lower data rates.
The specs also expand the data messages carried over Bluetooth beacons from about 30 bytes to about 256 bytes. As a result, beacons will be able to broadcast a URL rather than a unique identifier pointing to one, enabling greater ease of use.
Beacons are a much-talked-about but still nascent application, with about 8 million units shipping this year and a total of 565 million by 2021, according to ABI Research. They are used for retail advertising, automated museum docents, and even broadcasting a URL to a manual so that OEMs don’t have to print and ship one with a product.
A final mesh spec is the next big thing for Bluetooth, something individual vendors already support but won’t be formally ratified until about June. It will use a flooding approach that is simpler to implement than routing used on Zigbee and Thread.
The trade-off is that “all nodes receive information and pass it on, even when it is not relevant; this means devices spend more time awake and relaying information than is necessary, increasing the power consumption of the network,” said Andrew Zignani, an analyst at ABI.
Among its challenges, Bluetooth needs to get designed into more hubs and gateways to enable mesh and long-range links. The community also has an ongoing debate about support for IPv6 to end nodes, something that some see as critical for interoperability and that others say generates unnecessary power and memory requirements.
With Bluetooth 5 and eventually meshing, links can expand through a house or even a building without the need of device-to-device pairing.
“A Bluetooth light switch with a coin cell can last for years, and you can’t do that with Wi-Fi — there are a lot of apps that only need a small piece of data and low power and are only possible with Bluetooth,” said Mark Powell, executive director of the Bluetooth SIG.
Some 3.5 billion Bluetooth links are expected to ship this year, most of them in smartphones with the next largest group in wireless headphones and speakers. Apple’s decision to end support of headphone jacks in the iPhone is expected to drive wireless headsets to volumes greater than wired versions.
The smart home is Bluetooth's biggest growth area. Its share of the smart home market is expected to rise from 8% today to more than 26% by 2021, according to ABI Research. By contrast, 802.15.4 variants including ZigBee, Thread, and 6LoWPAN will rise from just under 17% of the market today to almost 30% by 2021.
The Nordic Bluetooth 5 chip comes in the same 7 x 7-mm package as its previous BLE device. (Image: Nordic Semiconductor)
For its part, Nordic Semiconductor is sampling its nRF52840 and Bluetooth 5 software to go with it. The chip is not slated for volume production until late next year. It also adds support for 802.15.4 radios and ARM’s CryptoCell-310 embedded security block.
The Nordic chip includes a power amp, boosting output power considerably to drive greater throughput and range. Nordic doubled flash to 1 Mbyte and quadrupled RAM to 256 Kbytes compared to its previous 55-nm part.
Similarly, Cypress is sampling a Bluetooth chip with a boosted power amp to extend range to 400 meters and data rates to 2 Mbits/s, albeit at the cost of higher power consumption. The CYW20719 complies with Bluetooth 4.2 and is “Bluetooth 5-ready.” Cypress also supports a Bluetooth mesh capability on its Bluetooth version 4.2 chips.
— Rick Merritt, Silicon Valley Bureau Chief, EE Times