Battery power allows some devices a respite from constantly needing to be plugged in.
In more recent years, wireless charging pads have made life easier.
You dont need to fiddle about reaching for a cable that fell or fumbled with plugging it in.
Wireless charging is super convenient and has even been integrated into things like desks and coffee tables.
So you dont even have to have a standalone charging pad.
It still only works if your phone is in the right spot.
The range of charging pads is basically nothing.
The way to fix this is pretty obvious, to increase the range.
This, however, comes with major technical hurdles.
Every few years, theres some movement in the field.
Xiaomi, however, is a household name.
Xiaomi also has a long history of pushing the envelope concerning high-speed phone charging, both wired and wirelessly.
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Why Is Room-Scale Wireless Charging so Hard?
Wireless charging works on the same principle as NFC and RFID cards and readers.
It takes advantage of a quirk of electromagnetism.
Any flowing electrical current generates a magnetic field.
A magnetic field can, in turn, induce an electrical current in a circuit.
This is how current wireless chargers work.
The problem is efficiency.
The magnetic field that is created spreads out evenly in all directions.
This means that the field strength drops off about the square of the distance.
Scaling up the technology isnt a viable solution, so something else needs to change.
Beamforming is a proven technology that you may use every day without even realizing it.
Modern Wi-Fi routers with multiple antennae use beamforming to increase their range and signal strength.
Beamforming works on the simple premise that waves can interfere with each other.
Suppose you have two ripples in a pool of water, and they cross over each other.
This happens with any wave, even light like the radio waves used in Wi-Fi.
In terms of Wi-Fi signal strength, those super peaks are hot spots.
Carefully adjusting the signal strength of multiple antennae creates a very customizable interference pattern.
The other devices on your data pipe are around as each of them moves.
Mi Air Charge does the same thing.
It just uses a different frequency of light.
It also uses the induced current to charge a machine rather than transmit data at high speeds.
Unfortunately, its a little more complicated than that.
Connected Wi-Fi devices generally broadcast back to the router through normal operations.
Wireless charging solutions dont necessarily have a returning signal to do this with.
Mi Air Charge has a base station with five antennae to get the whole thing to work.
These are used to precisely locate the beacon antenna in a compatible gear within range.
The receiving gadget has an array of fourteen antennae that convert the signal into power to charge the gadget.
Xiaomi claimsthat the technology can simultaneously transmit 5W of power to multiple devices.
Unfortunately, as great as this sounds, there is some bad news.
You could add the necessary electronics via an adaptor or charger case.
Unfortunately, doing so would add bulk and likely take up the charger port.
Another issue is likely the price.
While your phone already has an array of antennae, adding a few more wont cost too much.
The base station is different.
The base station would have to handle more power, which isnt too much of an issue.
It would also have to have almost a hundred and fifty antennae inside it.
That will start to cost a fair bit of money.
Youve also got the cost for the processing power required to handle everything.
Realistically, youre likely to have even higher prices for a few generations.
Such a so-called early adopter tax is standard on bleeding- and cutting-edge tech.
Bulk is probably going to be a minor issue.
The final issue, at least for the moment, is simply time.
Xiaomi originally announced Mi Air Charge in January 2021.
Its since made no further reference to it.
It has deleted the original announcement from its blog, though it can still be seen via theWayback Machine.
Conclusion
One of the things we didnt raise as an issue was the limitation to 5W.
This hints at the true strength of such a product.
Theoretically, it would be possible to power other devices in the same way.
Such a combination would likely also cut down on disposable battery waste.
Many IoT devices could also be made compatible with a wireless power system.
Indeed wireless power delivery would be a great convenient feature.
It is also likely to be a reality in the relatively near future.
It would be a bleeding-edge technology with associated high costs.
Without widespread adoption of devices, it also doesnt have an easy way into peoples homes.
To start using it, you would require new hardware and need to replace old hardware.
