Bluetooth: Remember us? Internet of Things before it was a Thing?
Bluetooth 5 unveiled, boosts range and coexistence, but no mesh yet
Analysis Bluetooth 5 has finally been unveiled, with headline claims of 200-metre range (quadrupling that of Bluetooth 4) and doubled bandwidth (now 2Mbps). There is a clear focus on Internet of Things devices and applications, but no sign of the proposed mesh protocol, which would do even more to improve the spec’s capabilities.
The Bluetooth SIG’s timing comes before the busy holiday season – and the launch window of the huge Consumer Electronics Show in Las Vegas in January.
This is Bluetooth’s attempt to provide device makers with a capable alternative to the low power mesh networking protocols that have been used in the smart home – namely, ZigBee and Z-Wave, and eventually Thread once it gets into gear.
For device developers and manufacturers, the big selling point for Bluetooth is the familiar brand, as well as plentiful chipsets at huge volumes, and that name recognition could go a long way towards selling more products into a consumer market that has met the smart home with a very reserved enthusiasm. Most industry watchers were predicting big things for the smart home market a few years ago, but we’ve yet to see the sector take off.
The SIG says that consumer devices with the new spec will be available within two to six months, and stresses that the protocol allows for new applications for Bluetooth – especially in the IoT. It specifically cites beacons as a main focus, noting Bluetooth 5’s improved location awareness and increased broadcast message size (800 per cent larger) that enable the tech to push alerts to users from these beacons.
But it’s not just advertising that would benefit from the improvements made to the beacon functions. Navigation in campuses or on mass transit are one very handy application, but the kinds of ambient data generation envisioned by the IoT are another use that would benefit from being able to transmit more (richer) data.
Range and coexistence
While the white paper that the SIG has published aims to tackle the perception that Blue-tooth is hampered by a short range, that 200 metre figure is quite a claim. We’re very interested in hearing from labs and researchers that put it to the test in real world and worst case environments, or if any manage to achieve the theoretical maximum of 444 metres.
But the SIG does note that, with a realistic 10dB sensitivity limit, a range of 140 metres is more realistic for Class 3 devices – rather than the 444 metres that is possible on paper. For the higher power Bluetooth devices, Class 2 (smartphones, headsets, with PCs more frequently found in Class 1.5) could hit 680 metres, and Class 1 (+20dBM, only permitted in FCC regulations, envisioned as whole-home access points) could go 4.3km. Those are very big numbers.
That paper cites a new Cypress Semiconductor EZ-BLE PSoC XT/XR module that can achieve a 400-metre line-of-sight (LoS) range, using an on-board power amplifier that boosts output to +9dBm, and a low-noise amplifier that provides a receive sensitivity of -95dBm. That 400-metre range allows a one-second connection interval, and a claimed average power consumption of 26.3 μa.
Etesian Technologies’ BreezeBT wind sensor is another example of a long range application, using a Laird BL600 module to hit a 110 metre range, powered just by the wind using energy harvesting tech. Etesian was able to extend the range to 400 metres using a newer Laird BL620 with an external antenna.
Bluetooth 5 takes coexistence capabilities with Wi-Fi a step further, according to Steve Hegenderfer, director of developer programs at the SIG. He told FierceWirelessTech: “We do something called channel hopping and we actually avoid channels that Wi-Fi uses … We’re good stewards of the bandwidth.”
A feature called Slot Availability Mask (SAM) enables Bluetooth to be a good neighbour to LTE, staying away from channels which are next to a channel in which LTE is transmitting.
"We are very serious about coexistence with other technologies, and when you think about the Internet of Things, there isn’t going to be one thing that rules the world,” he said. “Bluetooth is one of several so we want to do our part to be good neighbours with other technologies that are out there today and … we will constantly build and evolve our spec to make sure that coexistence and interoperability are key features of what we put out there.”
Copyright © 2016, Wireless Watch
Wireless Watch is published by Rethink Research, a London-based IT publishing and consulting firm. This weekly newsletter delivers in-depth analysis and market research of mobile and wireless for business. Subscription details are here.