Powercast’s Ubiquity uses RF to charge devices wirelessly

Power cast has unveiled its Ubiquity wireless power transmitters, which use radio frequency (RF) to charge devices over the air.

The Pittsburgh, Pennsylvania-based company showed off its Ubiquity transmitter, an ultra-low-cost RF power transmitter, at CES 2023, the major tech show in Las Vegas this week.

If this sounds a little crazy, it seems impossible to transfer electricity through the air to power an electronic gadget. Nicholas Tesla, the radio pioneer, tried unsuccessfully in the early 1900s. Since then, technical hurdles have plagued attempts to do the same.

But Powercast started in 2003 with the idea of ​​using radio frequency, which supplies its own power when making a connection between transmitter and receiver. The company said it shipped more than 10 million devices with more than 100 customers. The company has 79 patents. I wrote about wireless power way back in 2008, but we only got devices for inductive charging.

Designed as an economical RF wireless transmitter, Powercast has lowered the barrier to entry where RF wireless power can actually become ubiquitous with multiple RF transmitters covering every home, the company said.

“Powercast’s vision is to see an inexpensive RF transmitter in every room of every home,” said Charles Goetz,
CEO at Powercast, in a statement. “Like Wi-Fi routers, a home needs multiple RF transmitters to provide adequate RF coverage where convenient, contactless, ‘set and forget’ wireless charging becomes a reality. So we cut costs and share our Ubiquity design through a low $5 material cost reference design, or an embeddable module, that allows manufacturers to easily integrate RF transmitting capabilities into their own products to accelerate RF transmitter networks in homes.

There are two sides to Powercast’s over-the-air wireless power architecture. It has a transmitter that transmits RF over the air, and it has a receiver embedded in end devices that takes that RF from the air and converts it into DC (direct current) to both communicate data and power devices.

On the transmitter side, Powercast’s ubiquity will take several forms, all capable of both charging RF devices and communicating data back and forth throughout the home.

Manufacturers have two options for turning their own products — such as home appliances, TVs, gaming systems, computer monitors or AI-enabled home assistants — into ubiquitous RF transmitters. A licensable reference design allows manufacturers to integrate only the necessary electronics onto their own printed circuit boards for $5 or less bill of material (BOM) cost.

And it also has an easy-to-integrate, drop-in embeddable module that contains all the electronics and
hardware needed. Manufacturers will add a power supply and antenna. Powercast works with manufacturers to find an antenna design that best fits their specific product size.

Powercast also created its standalone Ubiquity transmitter that combines the embeddable module with an antenna to display at CES. Powercast will produce this transmitter the size of a portable loudspeaker.

On the receiving end, manufacturers can build Powercast’s tiny Powerharvester PCC110 receiver chip and a tiny antenna into their end devices for about $1, allowing them to work with an RF transmitter — either Powercast’s standalone Ubiquity, or RF transmitter products made using the Ubiquity embeddable module or reference design.

This wireless power-over-distance architecture can charge energy-efficient devices with continuous, reliable trickle charging in the background. Examples of end devices include TV remotes, electric toothbrushes, keyboards and mice, game controllers, earphones, headphones, smartwatches, fitness bands, hearing aids, clocks, electric razors, home automation devices and many more devices.

Jason Gill, Powercast’s director of R&D, said in a statement: “Volumes are in the consumer electronics market, but it is also price sensitive. In response to these manufacturers’ requests for a durable, ultra-low cost wireless charging solution, our engineers have perfected Ubiquity’s highly efficient single-antenna design that can transmit power as well as communicate data. Manufacturers can create eco-friendly, RF-powered ecosystems using rechargeable batteries or no batteries, both of which eliminate disposable battery electronic waste and battery replacement hassles.”

The Ubiquity transmitter can output up to one watt (3W EIRP) and will automatically charge multiple RF devices that enter the charging zone – no charging mats required. High-power devices charge faster within meters of the transmitter, while ultra-low-power devices, such as IoT sensors, can charge up to 30 meters away.

“The far-field wireless power transmitter semiconductor market will soon experience a strong growth trajectory
with most of the revenue coming from the consumer market,” said Phil Solis, director of research at IDC, in a statement. “On the receiver side, the consumer market will be the largest segment by 2024 and the vast majority of revenue by 2025. Low-cost solutions are needed to accommodate the many devices in the home that can benefit from wireless power.”

The licensable Ubiquity reference design is expected in February 2023. The Ubiquity module and transmitter are expected in June 2023.

How it works

A transmitter sends RF energy over the air to a receiver chip built into a device, which converts it into direct current to charge the batteries or power the device directly. This remote charging technology behaves like Wi-Fi, automatically charging powered devices when they are within range of a power transmitter.

Regulations in the United States and Canada limit the amount of transferable assets. Under FCC Part 15, power is limited to four watts EIRP and Powercast transmits approximately three watts EIRP.

A small Powerharvester receiver, embedded in systems or devices, harvests RF energy sent over the air from either a dedicated transmitter, such as Powercast’s Powercaster or PowerSpot, or from expected RF sources such as UHF RFID readers or NFC POS readers . The built-in Powerharvester then converts the RF into DC power to directly power that battery-less device or to charge the batteries.

The company said the charging is safe. A typical mobile phone user receives much more RF energy from their own mobile phone than from a properly installed Powercast transmitter. The charging devices can pass through walls.

Typical inductive charging solutions, such as charging pads and electric toothbrushes, require the power source and receiving device to be very close to each other to transfer power efficiently, usually within millimeters, which is essentially zero distance. These types of solutions typically require special alignment and charging pads or cradles. Powercast’s RF-based technology provides power-over-distance to one or more devices and does not directly compete with induction-based charging technologies.