By Steve Hegenderfer, Bluetooth SIG.
When first envisaged, Bluetooth was a revolution for the technology world. It provided a ground-breaking way to connect devices and people wirelessly. Equally as important, Bluetooth technology was easy for manufacturers to implement and consumers to use. As a result, a range of Bluetooth-enabled audio products such as headsets, speakers and automobile kits emerged, and to this day, continue to show strong growth in the marketplace. According to ABI Research, the Bluetooth-enabled wireless audio market is forecast to grow to more than 250 million units by 2018.
Introducing Bluetooth Smart
In 2010 the Bluetooth Special Interest Group (Bluetooth SIG) released its 4.0 specification with a new low-energy technology called Bluetooth Smart. This created new product possibilities for Bluetooth technology in many markets, including consumer electronics, medical and fitness. Designed to be very power-efficient and coupled with a common application development framework, Bluetooth Smart enables manufacturers to create sensor devices that can run on a tiny battery for months or even years. Developers can take advantage of the intelligent connections Bluetooth Smart allows by creating companion applications that take data collected from sensors and turn it into valuable information for consumers to view on their smartphone or tablet.
[caption id="attachment_5699" align="aligncenter" width="600"]
Secure Bluetooth Smart-enabled lock and Bluetooth-enabled smartphone.[/caption]
Analysts worldwide recognise Bluetooth Smart as a key enabler in the Internet of Everything. For example, ABI Research forecasts that over 3 billion Bluetooth-enabled devices will ship in 2014, and by 2018 there will be over 10 billion such devices in the market.
Bluetooth Smart is now being applied to the home automation market. According to ABI Research, the market share for Bluetooth Smart in connected home applications such as lighting, security and energy management will increase faster than any other wireless technology over the next five years.
Smart Home Applications
New Bluetooth Smart-enabled sensor devices are coming to market every day including locks, lighting systems, plugs and thermostats, all of which are offered with applications stored directly on Bluetooth-enabled smartphones, tablets, or in the cloud. Now users can securely lock and unlock their door without a key, turn on or off a light or change its colour, or receive an alert when a window is open - all from their existing Bluetooth-enabled smartphone or tablet.
[caption id="attachment_5700" align="aligncenter" width="430"]
Bluetooth-enabled smart light and smartphone.[/caption]
Indeed the sophisticated displays and applications on today's smartphones, tablets and other computing devices make it easy to control all of the appliances and systems throughout a smart home, leaving home automation developers with possibilities that are limited only by their imaginations.
Homeowners could, for example, use their Bluetooth Smart-compatible devices to adjust their heat and air-conditioning, monitor their energy consumption and fine-tune their appliance energy usage.
In the near future, TVs and stationary media streaming boxes, such as Roku, Apple TV and Amazon's new Fire TV, are going to serve the same hub functionality for the home that the phone or tablet does for Bluetooth Smart sensor devices today. The consumer will turn to their TV and entertainment console to serve as the connectivity centre for home automation in the future.
Why Consider Standards-based Wireless?
Bluetooth Smart is an application-friendly technology supported by every major operating system, however, for system developers, when a standards-based wireless technology is involved, there are some issues and concerns that are typically raised:
• Is the transmission of data secure?
• How much power do the wireless sensors require?
• What are the development and bill of material costs?
• How can I reach the greatest potential market knowing that there are countless smartphone and tablet device manufacturers and multiple operating systems?
These reservations however, can all be addressed by Bluetooth Smart, which offers significant advantages in home automation. It allows you to:
• Keep information confidential with secure wireless transmissions using 128-bit AES encryption.
• Design with a standards-based, low-power wireless technology your customers know and trust.
• Design using a cost-effective, highly-flexible development architecture.
• Leverage data with applications that are stored directly on Bluetooth-enabled smartphones and tablets, or in the cloud.
• Connect your device to billions of smartphones and tablets that consumers already own.
[caption id="attachment_5698" align="aligncenter" width="600"]
Devices such as smart plugs can be connected to the billions of smartphones and tablets that consumers already own.[/caption]
How it Works
The key difference between Bluetooth and Bluetooth Smart is that Bluetooth is
designed for wireless transmission of media. (e.g. from a source to a pair of speakers or a headset, and requires more power). Bluetooth was designed to support wireless communication with fixed and mobile devices, and for building personal area networks (PANs). It uses short-wavelength UHF radio waves in the ISM band from 2.4-2.485GHz, supports data rates of 1-3Mb/s, has a transmission range up to 100 meters (300 feet), and is able to connect a master with up to 7 slaves.
Bluetooth Smart on the other hand, is extremely power efficient , designed for lower-rate data and enables the ability for applications to collect data from Bluetooth Smart sensors and turn it into useful information on a smartphone or tablet.
Bluetooth Smart has a similar transmission range and operates in the same spectrum range as Bluetooth technology, although it uses a different set of channels. It has a bit rate of 1Mb/s and a maximum power transmission of 10mW, allowing a typical battery life ranging from months to years. The number of slaves is not defined, but is dependent on the implementation.
A Bluetooth Smart system will typically comprise a hub (or client) device such as a tablet or smartphone that initiates commands and requests, and accepts responses, and a server such as a temperature sensor that receives commands and requests, and returns responses.
[caption id="attachment_5701" align="aligncenter" width="600"]
Bluetooth Smart home control hub and server devices.[/caption]
The key advantage of Bluetooth Smart is that it works with the billions of smartphones and tablets that consumers already own. As long as the consumer has a Bluetooth Smart compatible smartphone, tablet or other hub device, then just about any Bluetooth Smart sensor device and application should work with it.
The main limitation of Bluetooth Smart is that although it supports all Apple iOS devices, on the Android side, it has only been fully integrated since Android 4.3. Smartphones and tablets operating on an earlier version of Android therefore, might not support a Bluetooth Smart device. This issue will resolve itself as all new Android devices launch with 4.3 or later.
Design Considerations
The integration of Bluetooth Smart into the smart home from a developer's perspective can be quite simple. Below are some pointers on what a developer should think about when adding Bluetooth to a smart home product.
• When creating your device, you need to ensure that you are working with suppliers that have the right components, in this case Bluetooth Smart modules/chips. You need to integrate the radio design into your overall designs for the product.
• Many devices now are able to update firmware over the air, and Bluetooth components are no different. So, if you think that your device-side application(s) or firmware might change, then make sure you consider chips that have that capability, as many do.
• A third and often overlooked consideration is what the consumers actually see; the controlling application. You should put some effort into good design for the application, and really think through the use cases for it. You should also think about how the functionality of the app might change by adding additional smart home components to it. Is the app extensible, or did you design a truly single-purpose app where it doesn't really make sense to add additional functionality? Do you want to have the ability to control other vendors' components via your app?
• What are the power constraints, and how will you handle them? Are you creating simple sensors which could run for many months on a single coin-cell battery, or will your device require more power due to its nature? Range also typically affects power consumption. Do you want to create an antennae that can produce longer range, but also consumes more power?
• Possible interference from other nearby wireless devices is also be something that a developer should consider. With its adaptive frequency-hopping technology, Bluetooth Smart is less susceptible to interference because it is constantly shifting from channel to channel. Still developers should consider the possibility of how potential interference could affect a user’s experience.
Conclusion
Whether trying to efficiently manage home energy or simply managing home lighting, developers are discovering and creating a new world of devices and applications thanks to Bluetooth Smart technology. As consumers continue to embrace Bluetooth Smart technology in home automation, the addressable market for a developer's solution is not in the thousands of potential customers, but in the millions.
Steve Hegenderfer is the Director of Developer Programs for Bluetooth SIG. Bluetooth wireless technology is the global wireless standard enabling simple, secure connectivity for an expanding range of devices and serves as the backbone of the connected world.
To learn about home automation, download the eBrief Catching the Next Wave in Smart Technology.
You can also join the Bluetooth SIG. SIG membership provides your company the license to use Bluetooth intellectual property and the Bluetooth brand. Plus the ability to network and collaborate with over 20,000 Bluetooth SIG members and the potential to influence the direction of the technology.
www.bluetooth.com/smarthome