The role of Bluetooth in the Internet of Things
As low-power networks take off, what’s the place of Bluetooth?
Invented by Ericsson in the early 1990s and initially standardized in 1999, most people associate Bluetooth with connectivity between a handset and an earpiece or mobile speaker.
But Bluetooth, which operates in the 2.4 GHz band using frequency hopping spread spectrum on 79 1-megahertz channels, has kept pace with technological evolution and found a place in both consumer-facing “Internet of Things” uses – smart homes and wearables, for instance – as well as in the industrial “Internet of Things” where adaptability and reliability are requisites.
To make this point, let’s take a look at a new Bluetooth module from Silicon Labs. The Blue Gecko BGM113 module has a 3-decibel milliwatt power output optimized for applications with a 150-foot range; the company says this is a good fit for “smartphone accessories, wearable sports and fitness products, wireless locks and point-of-sale devices.”
In keeping with IoT product trends in both the industrial and consumer space, unit price and battery life are huge considerations. The new module is said to “provides a compact, industry-standard footprint for Bluetooth low-energy applications where size, cost and time-to-market are key concerns,” said Riku Mettala, senior marketing director for module products at Silicon Labs.
The new modules, in unit quantities of 10,000, costs $4.17 per module and feature energy efficiency consumption of 8.7 milliamps at peak receive mode and 8.8 mA for peak transmit mode.
Tom Nordman, Silicon Labs marketing director for wireless modules, spoke at length about how Bluetooth goes beyond the consumer IoT to the industrial “Internet of Things.” Nordman said the technology, and the new Silicon Labs product, is “well-suited for industrial application scenarios where limited bursts of data must be delivered in real time in noisy environments. In a typical wireless smart sensor platform, Bluetooth can support the hardware interface, payload and communications needs of multiple inertial and position sensors, as well as actuators/motors used in instrumentation systems and predictive maintenance applications. Such designs also provide a means to change operating and monitoring parameters through specific firmware modules as over-the-air updates using Bluetooth’s point-to-point topology. Bluetooth’s frequency hopping capability makes it very reliable for industrial applications. The protocol is also extremely easy to use as developers can create point-to-point or point-to-multipoint connections with no infrastructure needed.”
Nordman also noted the Bluetooth low-energy specification (4.x and 5.x) is catching up to the Bluetooth Classic specification in terms of range and throughput, which he said will only drive further industrial IoT adoption.
“We believe industrial systems will gradually transition toward Bluetooth low energy in the coming years,” Nordman said. “Bluetooth low energy also provides much lower power consumption than Classic, which is useful in battery operated systems such as wireless sensors.”