How many Bluetooth radios do you own? Answer: More than you probably think. These chips are in your smartphones, cars, laptops, tablets, wireless speakers, headsets, mice, keyboards, game controllers, and others. You may own dozens. Double what you think, since it takes two radios to communicate.
That’s why Bluetooth is the best-selling wireless technology in the world. Billions of radios have been made and sold. Now Bluetooth is ready to add to that impressive outcome with the announcement of its latest version Bluetooth 5.
Last month, on December 7, the Bluetooth Special Interest Group (SIG) adopted Bluetooth 5 as the latest version of the Bluetooth core specification. Key updates to Bluetooth 5 include longer range, faster speed, and larger broadcast message capacity, as well as improved interoperability and coexistence with other wireless technologies. Recently, I got a briefing on the new standard from Steve Hegenderfer, Director of Developer Programs of the Bluetooth SIG. Here are some highlights:
1. Two Bluetooth classes: There are essentially two strains of Bluetooth, the older legacy or classic strain that encompasses versions 1.0 through 3.0 (including EDR). The other strain is the low-energy Bluetooth that includes versions 4.0, 4.1, and 4.2. The low-energy version uses a different radio technology than the classic strain. It employs frequency-hopping spread spectrum (FHSS) over the 2.4- to 2.483-GHz spectrum, but uses 40 2-MHz-wide channels rather than the 79 1-MHz channels of classic Bluetooth. Max data rate is 1 Mb/s. Most of the newer Bluetooth chips actually contain both types of radios.
2. Bluetooth 5 is an enhancement to the low-energy version: Version 5 bumps the data rate up to 2 Mb/s. It still uses the same GFSK modulation, though. The higher data rate decreases the transmission time of the messages sent to better conserve power. The basic power output level is 0 dBm or 1 mW, but higher-power classes of Bluetooth can also be used. The options are 4, 10, or 20 dBm for extended range.
3. Extended range: Low-energy Bluetooth has a nominal range of 10 to 30 meters. Bluetooth 5 extends this to the 30- or 50-meter range. Actual range depends entirely on the environment, but longer range means more potential uses. With a line-of-sight path, the range can be many hundreds of meters. The longer range in Bluetooth 5 is achieved by using a strong forward-error-correction (FEC) scheme to correct errors. It trades off speed for range, which is a positive feature for some applications.
4. Greater message capacity: The new version 5 ups the payload capacity of it packets. Data packets can now be in the 31- to 255-octet range, and that means fewer transmissions and less broadcast time.
5. Interference mitigation: Bluetooth 5 also incorporates features to better minimize interference. Remember Bluetooth shares the 2.4-GHz ISM band with Wi-Fi, ZigBee, and a bunch of other wireless devices, so there’s a greater likelihood for interference. The new features detect and prevent interference at the band edges.
With these key improvements, Bluetooth 5 is set for greater adoption in the Internet of Things (IoT) arena. New applications in the consumer home-automation space, such as controlled lighting, are possible.This is especially true for industrial IoT, where the new Bluetooth 5 features are a good fit for low-data-rate sensor reading with greater range, security, and reliability.
One factor that may help Bluetooth 5 expand into IoT apps for the enterprise and industry is the new routers and access controller from Cassia Networks. These products make it easy for Bluetooth devices to connect to via the internet, opening the door to many new potential uses. Version 5 should also expand its reach into the area of beacons for proximity sensing and location messaging. And all the while, Bluetooth 5 is backwards-compatible with the 4.x versions.
If you’re looking for a wireless technology for your forthcoming IoT project, give Bluetooth some consideration. It’s now more competitive than ever with ZigBee, ANT, and Thread technologies. Market data firm ABI Research forecasts that Bluetooth low-energy version devices will exceed five billion shipments by 2021.
By the way, if you need further details on Bluetooth 5, I urge you to go to the SIG website. The SIG offers a selection of developer kits, too, that speed up and simplify new product design. Also, if you need a good background in the low-energy versions, get the new book Inside Bluetooth Low Energy, by Naresh Gupta, recently published by Artech House.