The Internet of Things looms as possibly the most disruptive shift in technology since the creation of the Internet itself. Analysts estimate that up to 30 billion devices will be wirelessly connected by 2018. According to recent reports, the average U.S. household already charges up to 10 devices at any one time, and that number is expected to rise as the number of connected devices continues to surge. Imagine charging multiple devices, including a smartphone, tablet and smartwatch on a single surface — no more fussing around with multiple chargers and outlets.
Wireless power, which allows users to charge multiple electronic devices without the use of a cable, promises to finally cut the cord for good. While wireless power technology has been around for some time, its evolution from first-generation inductive technology to second-generation resonant technology is now promising to take it mainstream.
With inductive technology, two coils are required — a transmitter and a receiver. An alternating current is passed through the transmitter coil, generating a magnetic field that induces a voltage in the receiver coil that is used to power a mobile device or charge a battery. And while inductive technology has certainly helped create an interest in wireless charging, it is not without its limitations. Inductive technology only allows the user to charge one device at a time, and that device must be precisely aligned on a charging pad.
Limitations in inductive technology are not the only reason wireless power has failed to take off. Confusion and frustration over multiple competing standards from different organizations have also muddied the waters. For wireless charging to finally go mainstream, the individual specifications must either work seamlessly together or converge to a single unified standard.
That’s exactly what appears to be happening, thanks to resonant wireless technology. Promoted by both the Alliance for Wireless Power (A4WP) and Power Matters Alliance (PMA), resonant technology is based on the concept of spatial freedom. Unlike older technologies, it uses the principles of magnetic resonance, which brings a number of unique benefits.
Resonant wireless technology features a simple transmitter antenna designed for multiple receiver support, a comprehensive wireless power control system using Bluetooth Smart communication, and has the ability to transfer power through non-metallic surfaces. Bluetooth Smart provides a reliable communication channel between wireless power receivers and charging surfaces. This means that even the smallest of devices, such as headsets and wearables, will be able to communicate clearly and intelligently with the charging surface. The technology is convenient and simple to use and its spatial freedom allows multiple devices to be simultaneously charged with one transmitter and without the need for precise alignment.
These benefits are driving the multiple specifications to collaborate and combine efforts toward convergence — likely to occur by the end of this year. Once the convergence happens, more and more wireless charging solutions will hit the market. And because it will be easier to charge multiple devices at the same time, wireless charging makes sense for the burgeoning IoT marketplace such as fitness trackers, wearables and health monitors.
Imagine what that capability will mean for industries, retailers, service providers and consumers. Wireless charging stations could start popping up everywhere from coffee shops, airports, restaurants, movie theaters and furniture. Consumers would have the ability to charge their devices nearly everywhere. Retailers and service providers could even use wireless charging to deploy value-added services to personalize a mobile user’s experience at their favorite stores, airports and other businesses.
Getting to this level however, will require the availability of an end-to-end solution for resonant wireless power that original equipment manufacturers (OEMs) could incorporate into a wide variety of devices. It will need to be backward-compatible with inductive wireless chargers and be able to ensure interference-free operation.
There is little doubt that wireless charging is a cool feature for any smartphone user. In the IoT-driven world, however, where consumers will have dozens of Internet-connected devices, it will be absolutely essential. The convergence of the efforts of the industry toward one standard based on resonant technology and the availability of a single end-to-end wireless power solution will go a long way in driving wireless power into the mainstream and enabling the vision of a connected world to reach its full potential.
With ABI Research projecting shipments of 100 million wireless power-enabled devices by 2015 and 400 million wearable devices by 2018, those advances can’t come soon enough.
Reinier van der Lee is director of product marketing for the Mobile and Wireless Group at Broadcom, responsible for the product definition and marketing of power management (PMU) chips for mobile devices. Van der Lee joined Broadcom from Philips Semiconductors in the Netherlands (now NXP Semiconductors). He serves on the board of directors of the A4WP Alliance for wireless power, and is co-author of 17 patent applications, of which six related to wireless power and power management have been granted. Reach him @Broadcom.