We are starting to see the first beacons and gateways that truly support Bluetooth 5 even though the standard was released in 2016. Up to recently, some have claimed to support Bluetooth 5 in that the internal hardware and software (SDK) was Bluetooth 5 capable but most, if not all, of the Bluetooth 5 features weren’t available.
Compatibility is dependent on smartphones supporting Bluetooth 5 that has also only come to fruition with recent phone models. Most Android smartphones manufactured in the last few years use Android 10 or Android 11 that has Bluetooth 5 software support. However, the Bluetooth chip inside the smartphone also needs to support Bluetooth 5. On iOS, all including and after iPhone 8/8 Plus/iPhone X support Bluetooth 5.
Furthermore, there’s also the complication that Smartphones claim to be Bluetooth 5 capable but might not support many of the optional features. One way to test which features are supported is to use the Nordic Semiconductor nRF Connect app. Here’s an example from the ‘Device Information’ section of the app running on a Pixel 3a XL:
We now have the INGICS iGS03E Bluetooth to Ethernet gateway in stock. This differs to the iGS02E in that it includes Power over Ethernet (PoE) without having to have an external PoE splitter.
Gateways look for Bluetooth LE devices and sends their advertising on to a server via TCP, HTTP(S) or MQTT including AWS IoT. If you use with sensor beacons, this provides a quick and easy way to provide for IoT sensing.
The iGS03E is one of the first gateways to also support Bluetooth 5 in Long Range mode (LE Coded PHY), although very few advertising devices support this yet.
We have a new rugged, UV-resistant, waterproof (IP68) sensor beacon, the AC-BLE-T110G in stock.
This is the first beacon we know of that supports Bluetooth 5 Long Range Coded PHY. While many beacons mention Bluetooth 5 in their specification and a Bluetooth 5 SDK has been used in their development, they only transmit Bluetooth 4.2 advertising. This beacon is the first to support Bluetooth 5 Long Range Coded PHY to achieve a range up to 200m with compatible gateways and smartphones.
This beacon can also be set to detect motion with a user defined threshold (mg) and duration (ms) which sends an alternative iBeacon id, a configurable number of times, instead of normal advertising.
Martin covered scanning, GATT, how to maximise data rates, speed vs reliability and using different PHY for enhanced range or data rates. The second part of the talk covers Bluetooth Mesh and proxy nodes.
One thing not mentioned in the slides, to be careful of, is that connection via a proxy node is relatively slow because it’s limited by the GATT connection. Proxy nodes are good for controlling (sending small amounts of data into) a Bluetooth Mesh but poor if you want to use the connected Android device as a gateway for all outgoing data.
There’s a new virtual Bluetooth Developer Meetup arranged for 15th October 2020. The first event will include talks from experienced Bluetooth developers from Google, Samsung, Foundries.IO and Bluetooth SIG.
The Bluetooth SIG has recently released a 2020 Bluetooth® Market Update identifying new trends and forecasts from ABI Research and other analyst firms.
The use of Bluetooth for location is expected to achieve 32% compound annual growth (CAGR):
Obviously, these and other numbers in the report were analysed prior to the coronavirus crisis.
For Bluetooth Mesh, 90% of end-product Bluetooth® mesh qualifications are lighting focused. As with the introduction of iBeacon, which initially focused on marketing messages, the wider capabilities and opportunities are initially not being fully exploited. Part of the problem is that the standard models that come with Bluetooth Mesh are more lighting focused because the standard was driven by individuals from the lighting industry. Custom models, such used by our SensorMesh™, are possible but take more effort.
Today’s Bluetooth devices use advertising, GATT connection and mesh. Advertising occurs over three channels to reduce the affects of wireless interference. When more than one device advertises at the same time, the data is lost. However, advertising takes of the order of 1ms so the chance of collision is usually small.
In contrast, BlueFlood uses concurrent transmissions (CT) that purposely synchronise transmissions such that if colliding packets are tightly synchronised and have the same contents, the resulting signal might be distorted, but highly probable that they do not destruct each other. This is used with the Glossy flooding protocol and 40 rather than 3 advertising channels.
CT-based protocols achieve enormous performance gains in terms of end-to-end reliability, latency and energy consumption even under harsh interference conditions
Concurrent transmissions are challenging using Bluetooth because transmissions need to be synchronised down to 250ns. Nevertheless, the researchers show this is possible using standard Bluetooth PHY and commercial Nordic SoCs. They achieved an end-to-end loss rate below 1% and managed to receive the signals on a standard smartphone. While the mechanism was fragile it was found to be viable.
There’s a push by the Bluetooth SIG at the moment, promoting long range Bluetooth that appeared with Bluetooth 5 in June 2016. This is presumably because, to date, there haven’t been many long range end-user products. There aren’t many devices out there because you need Bluetooth 5 hardware at both ends of communication and existing devices can’t be upgraded.
Device manufacturers have been waiting for the ‘device at the other end of the communication’ (beacons, sensors, smartphones, single board computers) to become compatible before creating new products using Bluetooth 5 which is a chicken and egg situation. There are also tradeoffs around backwards compatibility and battery power. It’s more complex to create a device that supports Bluetooth 5 and is backwards compatible with Bluetooth 4. Advertising both at the same time uses more power and hence reduces the battery lifetime.
In order to validate Bluetooth 5’s long range claims, Nordic have a new blog post testing long range. The post gives a good explanation of path loss, outside vs inside and deterioration of the signal due to precipitation, humidity and reflected signals. Nordic also have an older post comparing the range of BLE, ZigBee and Thread Protocols.