Bluetooth and emerging product innovation
Imagine a future where all your devices talk to each other and are a tap away from your fingertips or a voice command to your phone.
This is a future that is long overdue. And it is happening now in 2014 almost two decades since bluetooth was invented in Ericsson’s labs in 1994. The years of 2013 and 2014 – in my opinion – are turning out to be the years of bluetooth device innovation.
If we take Kickstarter.com as one of the canaries for emerging hardware innovation and market demand, a quick search on Kickstarter.com will show you 1-4 bluetooth-related projects at any time. Interesting consumer-health-and-fitness projects like fitbit and jawbone are also leveraging on the maturity of the bluetooth protocol to great success. The rise of the Internet-of-Things trend will continue to see a demand for devices that can transfer data and instructions seamlessly between each other. While I am no betting man, I can safely bet that bluetooth is going to be one of the two major protocols (the other being Zigbee) that these devices will support.
Evolution of Bluetooth and various protocols
Here’s an interesting table that lists out the different wired AND wireless communication protocols and how they have all evolved through their respective version over the last decade (for bluetooth) or more (for the rest):
|V.21: 0.3 kbps||802.3i: 10 Mbps|
|V.22: 1.2 kbps||802.3u: 100 Mbps|
|V.32: 9.6 kbps||802.3ab: 1000 Mbps|
|V.34: 28.8 kbps||802.3an: 10000 Mbps|
|802.11: 2 Mbps||v1.1: 1 Mbps|
|802.11b: 11 Mbps||v2.0: 3 Mbps|
|802.11g: 54 Mbps||v3.0: 54 Mbps|
|802.11n: 135 Mbps||v4.0: 0.3 Mbps|
Interestingly, Bluetooth 4.0 (also referred to as BLE — Bluetooth Low Energy) has implemented a lower rate of data transfer. What’s up with that, you ask?
BLE devices designed to be wearable, such as FitBit, Polar’s heart-rate-monitor, Jawbone do not have a direct power source and are instead powered by button-cell (Lithium) batteries. Bluetooth 4.0 protocol is therefore re-designed to handle this new requirements for the emergent wearable device market. This single point is the most important difference between classic (3.0) and low-energy (4.0) variants of bluetooth.
BLE vs Bluetooth Classic = different bluetooth devices
To cater for different real life use cases in the market, the bluetooth protocol does not restrict you to choose one version over the other. It is entirely possible to build a device that can operate with bluetooth 3.0 (classic) and bluetooth 4.0 (BLE).
Here’s a summary of 3 different bluetooth device types you can build.
A classic bluetooth device will support only data transfers over bluetooth 3.0. A single-mode device will operate only with BLE while a dual-mode device can work with classic bluetooth as well as with BLE.
Bluetooth low energy is not trying to optimize bluetooth classic. Bluetooth low energy represents a complete re-design of the technology stack with ultra-low power consumption in mind. The re-design is implemented from the physical layer all the way up to our application (program) layer, as decided by Bluetooth SIG (Special Interest Group) in a cooperative, open but commercially driven standards. This is a non-trivial note of success as it is extremely challenging implementing these design standards among competing commercial bodies. The remarkable growth of BLE adoption over 2013 to 2014 is a testament to Bluetooth SIG framework’s success.
Implications at implementation level?
So what’s the difference with BLE’s re-design? The Physical Layer’s radio parameters have been relaxed in BLE, in contrast with bluetooth classic’s radio implementation. This means that the radio can use less power when transmitting or receiving data. The link layer is optimized for very rapid reconnections and the efficient broadcast of data so that connections may not even be needed. The protocols in the host are optimized to reduce the time required for application data to be transferred once a link layer connection has been made.
All these are designed with the low power goal in mind, trading off the high speed of data transfer (54 Mbps for Bluetooth 3.0), for low energy usage.
With all these in mind, when you build your bluetooth device, these will therefore be the considerations you take into account, when deciding which type of device you want to build, to support your user/customer’s behavior.
Bluetooth 3.0 and biuetooth 4.0 are technologies designed with very different requirements and goals (even if they share similar roots). The advent of bluetooth 4.0 has enabled the entire gamut of wearable device innovations since its release from mid 2010 and will continue to do so.
Fundamental change in technology design are inevitably linked with product/commercial innovation. Bluetooth 4.0 (BLE) is a perfect example where tech meets commercial innovation.