Wireless Power for IoT Sensors
To Qi or Not To Qi: IoT Sensors Introduction
NuCurrent has been driving the wireless power industry for over a decade, launched more product categories into mass production than any other company in the world, and developed a global reputation for technology innovation with over 150 patents and many contributions to global standards bodies like the WPC, Airfuel, and NFC. NuCurrent sets customers up for wireless power success by posing five essential questions to determine which wireless power transfer method will be most effective for IoT sensors.
While Qi-based (inductive) charging is the best-known method of wireless power transfer, there are several other options for product developers to consider. In the To Qi or Not To Qi: Introduction video, NuCurrent explores and defines the different wireless power transfer methods available and details key terminology and concepts along the way.
Best Wireless Power Transfer Methods for IoT Sensors
IoT sensors are low-power devices that gather data to inform calculated decisions. Each IoT device has individualized requirements from the sensor, such as power transfer levels, data transfer, and sensor sizing restrictions. The special requirements eliminate the possibility of a one-size-fits-all solution, resulting in the need for a custom wireless power solution. In To Qi or Not To Qi: IoT Sensors, NuCurrent reveals why RF and NFC are the best wireless power transfer methods.
It involves IOT sensors that you might find
in an industrial setting or retail setting.
There's some different options here,
but each of them has some challenges.
So can you please walk us through your thinking
of these questions for IoT-type sensors?
I think of the plethora of different devices
that we have placed all around, you know, the environment.
So the first question I ask myself is,
"What is the size of the product?"
And "What is the size of the antenna required?"
You know, there are possibilities of IoT sensors
that you place within a grocery store
that are on the shelves, that are the sensors,
that are, you know, measuring people capacity,
or whether items are still on the shelf or stocked.
Those tend to be relatively small and fixed in location.
I also think of IoT sensors as some of the things,
temperature sensors or impact sensors
that you place within packages.
So those have, you know, a larger size
compared to the first types of sensors that we talked about.
The third type of IoT sensor that I'm kind of visualizing
in my mind is something like a SmartLock.
The ability to open your door via an app
because your lock on your front door is connected
to your home network.
And you can basically let people in or give a code
and use that functionality.
So when I think of IoT sensors,
I think of lower-power devices,
but with a larger breadth of sizes.
From that, I kind of think RF and NFC
are the appropriate technologies to approach this
based off the power levels and the size requirements.
the low frequency or Qi-option,
high-frequency, and the hybrid.
So as we zero in on RF and NFC as options,
we started to see a couple of yellow boxes
in each of the columns for question two and three.
Can you walk us through those?
So this is kind of where both RF, NFC are viable options
but they have trade-offs in different places.
So from a power level standpoint,
RF really can only supply a couple of milliwatts of power
over the larger distance, where you find the benefit
of RF wireless power happening.
As a result, the IoT sensor in order to get anything
greater than a couple of milliwatts would have to be
right next to the transmitter.
Which kind of eliminates the purpose of that RF,
let's say, user experience.
With NFC, I give it a plus because we are able,
in a close coupling position, deliver up to 3 Watts
of power to the device.
So if your sensor that you're looking to power
is a little bit more power-hungry,
NFC definitely has the edge up here.
If your IoT sensor is on the lower-power scale,
think a couple of milliwatts,
and has relatively fixed position,
I would say RF is, you know, a potential solution.
So, on this question, I give NFC the thumbs up
due to the capability.
and sort of a case-by-case walkthrough
as folks evaluate this.
But clearly, RF and NFC have their different pros and cons.
Take us through the next two questions, Jason,
in terms of how these might play out
in the thinking process.
"What is quote unquote distance
"and how many receivers are you going to need to charge?"
Kind of going back to that first question
about the size of the product.
RF has a big, you know, let's say, it has an advantage here
relating to very small, low power devices
but multiple of them within all locations.
So if you picture a Walmart warehouse,
where you have sensors that are measuring
the amount of goods within a specific shelving unit
or the temperature across the entire warehouse,
these fixed extremely low power devices
having an RF solution allows you to charge multiple devices
at once at these low power levels.
So from a implementation standpoint, it makes quite a bit
of sense to use RF in this kind of technology.
With NFC, you know, we're talking about close coupling.
The devices have to be relatively close to each other.
So that's why I kind of give it a minus
because it is kind of forced to be in one
kind of orientation compared to RF.
But it does give you the higher power levels.
So in this specific topic, I give RF the plus
specifically for the use case of the product.
But NFC is a close second.
the pros and cons and trade offs of these two solutions.
When you look at question four, question five,
it sounds like the prospects are agreeable for both.
But is there anything you'd like to mention
about those two questions for the audience here?
So from an RF standpoint, there are proprietary ecosystems
being created by OSSIA and Energous to be able to,
let's say, enable these types of warehouses.
If you're looking for something that is more ubiquitous
on a global scale, unfortunately, it's not there.
You are going to have to state
that this proprietary ecosystem created by these companies
in order to get that, let's say, true RF experience
that you're looking for.
With NFC, again, you're not getting
the larger charts systems but you have the ability
to use quite well-known
and well-established technology within NFC.
Both from a charging aspect as it's, you know,
being ratified from the WLC,
wireless charging for NFC form
and also from a data standpoint.
So if you're looking for something
a little bit more proprietary and enclosed,
RF might be appropriate solution for you.
If you're looking for something that can utilize
NFC technology from a data and a charging standpoint,
NFC is obviously going to be the path for you.
And then question five, depending on the data requirements,
nice thing about RF is you can get a continuous data stream
going on a very regular polling pace
because you're usually connected
to your IOT sensor consistently.
Because you have to power it and you can transfer the data
over the RF link.
With NFC, it's more of a tap to pair or, you know,
applying your device to a sensor to extract data from it
but also potentially give it a charge back
or enable some additional features.
So the use case is a little bit different.
RF definitely has a benefit for continuous data.
While NFC allows you to implement and provide more power
to get additional features or retrieve diagnostics
or provide, you know, programming feature to it.
So both have their benefits here.
So that's why I give them both a thumbs up.
us through that.
It looks like, you know, depending on the case,
depending on the use case and the application,
these are two areas that you want to explore on the RF side.
You'll see offerings from OSSIA, Energous, or Powercast even
on the RF applications.
And then on the NFC side, you know, Nucurrents
leading the way with our Nueva and a (mumbles) platform.
So thanks for walking us through this one.
And we'll move on to the next.
Is Qi Charing for Laptops the Way to Go?
Qi-based (inductive) charging is the most popular form of wireless power, and for good reason. But there are many more power transfer methods to consider when deciding which is best for your device.
In this 60-minute session, NuCurrent will look into the different wireless power transfer methods available and walk through the tradeoffs that come with each method, followed by a recorded Q&A session.
The Power to Get to Production