Magnetic fields provide a new way to communicate wirelessly

Magnetic fields provide a new way to communicate wirelessly
Jiwoong Park, an electrical engineering Ph.D. student and first author of the study, demonstrates communication from arm to arm using the magnetic field human body communication prototype developed in Mercier's Energy-Efficient Microsystems Lab at UC San Diego

Electrical engineers at the University of California, San Diego demonstrated a new wireless communication technique that works by sending magnetic signals through the human body. The new technology could offer a lower power and more secure way to communicate information between wearable electronic devices, providing an improved alternative to existing wireless communication systems, researchers said. They presented their findings Aug. 26 at the 37th Annual International Conference of the IEEE Engineering in Medicine and Biology Society in Milan, Italy.

While this work is still a proof-of-concept demonstration, researchers envision developing it into an ultra low power wireless system that can easily transmit information around the human body. An application of this technology would be a wireless sensor network for full-body health monitoring.

"In the future, people are going to be wearing more electronics, such as , fitness trackers and health monitors. All of these devices will need to communicate information with each other. Currently, these devices transmit information using Bluetooth radios, which use a lot of power to communicate. We're trying to find new ways to communicate information around the human body that use much less power," said Patrick Mercier, a professor in the Department of Electrical and Computer Engineering at UC San Diego who led the study. Mercier also serves as the co-director of the UC San Diego Center for Wearable Sensors.

Communicating magnetic signals through the human body

The new study presents a solution to some of the main barriers of other : in order to reduce power consumption when transmitting and receiving information, wireless systems need to send signals that can easily travel from one side of the human body to another. Bluetooth technology uses electromagnetic radiation to transmit data, however these radio signals do not easily pass through the human body and therefore require a power boost to help overcome this signal obstruction, or "path loss."

Magnetic fields provide a new way to communicate wirelessly
A prototype of the magnetic field human body communication, developed in Mercier's Energy-Efficient Microsystems Lab at UC San Diego, consists of magnetic-field-generating coils wrapped around three parts of the body, including the head, arm and leg. Credit: Jacobs School of Engineering, UC San Diego

In this study, electrical engineers demonstrated a technique called magnetic field human body communication, which uses the body as a vehicle to deliver magnetic energy between electronic devices. An advantage of this system is that magnetic fields are able to pass freely through biological tissues, so signals are communicated with much lower path losses and potentially, much . In their experiments, researchers demonstrated that the magnetic communication link works well on the body, but they did not test the technique's power consumption. Researchers showed that the path losses associated with magnetic field human body communication are upwards of 10 million times lower than those associated with Bluetooth radios.

"This technique, to our knowledge, achieves the lowest path losses out of any wireless human body communication system that's been demonstrated so far. This technique will allow us to build much lower power wearable devices," said Mercier.

Lower power consumption also leads to longer battery life. "A problem with wearable devices like smart watches is that they have short operating times because they are limited to using small batteries. With this magnetic field human body communication system, we hope to significantly reduce as well as how frequently users need to recharge their devices," said Jiwoong Park, a Ph.D student in Mercier's Energy-Efficient Microsystems Lab at the UC San Diego Jacobs School of Engineering and first author of the study.

The researchers also pointed out that this technique does not pose any serious health risks. Since this technique is intended for applications in ultra low power communication systems, the transmitting of the magnetic signals sent through the body is expected to be many times lower than that of MRI scanners and wireless implant devices.

Another potential advantage of magnetic field human body communication is that it could offer more security than Bluetooth networks. Because Bluetooth radio communicates data over the air, anyone standing within 30 feet can potentially eavesdrop on that communication link. On the other hand, magnetic field human body communication employs the human body as a communication medium, making the communication link less vulnerable to eavesdropping. With this technique, researchers demonstrated that magnetic communication is strong on the body but dramatically decreases off the body. To put this in the context of a personal full-body network, information would neither be radiated off the body nor be transmitted from one person to another.

"Increased privacy is desirable when you're using your wearable devices to transmit information about your health," said Park.

Demonstrating magnetic communication with a proof-of-concept prototype

The researchers built a prototype to demonstrate the magnetic field human body communication technique. The prototype consists of copper wires insulated with PVC tubes. On one end, the copper wires are hooked up to an external analyzer and on the other end, the wires are wrapped in coils around three areas of the body: the head, arms and legs. These coils serve as sources for magnetic fields and are able to send magnetic signals from one part of the body to another using the body as a guide. With this prototype, researchers were able to demonstrate and measure low path loss communication from arm to arm, from arm to head, and from arm to leg.

Researchers noted that a limitation of this technique is that magnetic fields require circular geometries in order to propagate through the human body. Devices like smart watches, headbands and belts will all work well using , but not a small patch that is stuck on the chest and used to measure heart rate, for example. As long as the wearable application can wrap around a part of the body, it should work just fine with this technique, researchers explained.

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Citation: Magnetic fields provide a new way to communicate wirelessly (2015, September 1) retrieved 17 September 2019 from
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User comments

Sep 01, 2015
I already saw a much better version of this at MIT about 2 years ago.

Sep 01, 2015
IBM solved this problem in the 1990s

Sep 01, 2015
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Sep 01, 2015
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Sep 01, 2015
No, no, no, no, and no again.

do not transmit magnetic or encoded electrical signals through the human body.

The human body FUNCTIONS via incredibly subtle electro-chemical signals and conditions.

It is self correcting, via the function of the body itself. This is why we have as few cancers as we currently have, is the deal. If the body was not self correcting, it would be far far worse due to the levels and types of environmental inference in the modern world.

When we are young, this system is stronger, more active, more robust than it is when we are older. Hence the increase in cancers and other similar issues of the old and older.

Stay so far away from this sort of insanity that you beat it to death with extreme prejudice, and do it from a safe distance.

It is impossible to say NO loud enough and hard enough and often enough to this kind of uninformed and foolish shit. Fuck ----- no. Just no.

Sep 01, 2015
KBK: Actually it's pretty easy to say no as often as you want when you don't have to actually prove any of the things you said. Maybe people should stay away from your insanity too?

Sep 01, 2015
Grow up and read. Get educated, get real, Understand a few things. The body is electro-chemcial and it is subtle.

This 'solution' to a quite obviously engineered in a total vacuum of knowledge of human body function.

What are you going to do? Slowly increase the subtle and gross environmental pollution and interference, over time in consistent exposure, until you reach the cancer producing state, on a 15 year old? When are you going to wake up on that, when you reach the LD-50 on that 15 year old's robust electro-chemical function?

This proposal is an obviously uninformed idea.

Sep 01, 2015
As for being informed and bona fides, etc..

I know people in the medical research field. For over 20 years.

A research field, a medical and biological research grouping of people, a large grouping (including many cancer researchers) this case, full of researchers and organizations that are free of corporate and financial interests.

In a country where the government and university level researchers are MANDATED to still be FREE of corporate and moneyed interests from interfering with their works.

And you know what they say to stuff like this proposal?:

No, no, no, no, and ----fuck no.

Sep 01, 2015
I also think it is not a good idea to use body as a conductor for any fields, whether magnetic or electric. Consider the case with antibiotics. They were yesterdays wonder drugs until it was discovered that they also deplete the good bugs, that actually are protecting us from pathogens. And here, because current medicine is only seeing the chemical side of animals like in us humans, the effects and functioning of electrical side of us is understudied in standard medicine. But it does not mean that one could mess with that side without effects. We are already living in electrosmog that does not need any more pollution by wearable tech. I think it might still be better to use this magnetic system than bluetooth for on person communication. But that should be studied, not just assumed to be so.

Sep 01, 2015
Recall when Dallas semiconductor brought out the one-wire serial interface, around that time of late 1980's I used it in two products, there was a release by IBM & an independent co that shaking hands with someone was sufficient to establish a one-wire equivalent to Dallas Semi interchange exploiting several combinatorial parasitic electronic effects to exchange the electronic equivalent of a business card - these days we call that a V-card or .vcf file etc ~1KBytes

Whilst docile claims, with immense ignorance of fundamentals in; gross magnetics/induction, rf, capacitance, impedances etc immaturely attacking "The Scientists"
The scientists are getting plain imbecile, it's terrifying.... :-(
Why offer comment on a technical aspect of a Physics field you are so completely ignorant of ?

docile, you come across as a "comment bot", are you a real person or some freshman's cognitive conversational IT project ?

Seen you go "off-beam" so many times, you embarrass :-(

Sep 01, 2015
do not transmit magnetic or encoded electrical signals through the human body.

Charge re-balancing at the cellular level will cure cancer. There are a couple of ways to do this. A structured magnetic field is the best way. You'll hear about it soon.

Don't ask me why (I'm just an artist), but I believe this may have more validity than we know...

Sep 01, 2015
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Sep 01, 2015
bschott claims
Charge re-balancing at the cellular level will cure cancer
Really ?

Show combinatorial isoelectric field effects of the thousands of proteins in situ - PLEASE ?

Head of proteins bschott, where do you get your snake-oil crap from please - any journals ?

bschott went of showing ignorance
There are a couple of ways to do this
Really ?

References please, as its well known cancer is principally cells ignoring apoptosis signalling, ie Old cars not recycled etc ?

Where do you get your pseudo crap from & why post it without any education - PLEASE ?

bschott with even more crap
A structured magnetic field is the best way
Structured ? how ?

Static or dynamic ?

If former then how is it aligned with any dipoles as they are dynamic & how often, @ what frequency ?

If latter then how does one orient a field to match, reinforce or cancel, when, how often in regards to what stimulus, any issue with CD47 etc - really ?

When ?

Sep 01, 2015
docile asks
Do you have some matter of fact objection against my post?
Yes. You write as if you are completely ignorant of majority of core Physics, Electronics & your language betrays that rather substantively !

docile states
The whole article comes from http://www.jacobs...?id=1807
So what ?

It doesnt necessitate your puerile response of
The scientists are getting plain imbecile, it's terrifying.... :-(
What does it mean ? Are you unable to articulate ?

Your comments suggest plainly to those who are keenly educated in Science ie Physics ie Electronics etc your comments are naive immature critique by an uneducated kid !

As I say, I've seen you act like a bot, you make collections which don't show education or training & which are far more consistent with mindless bot-like reactive activity commensurate with a program as part of a masters/PhD project in responsive/dialog conversation IT experiments...

Sep 01, 2015
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Sep 01, 2015
This comment has been removed by a moderator.

Sep 01, 2015
Oh dear. Ignorance of Maxwell's laws is rife. Essentially, they're using the near H field from a loading coil. The body acts as a very lossy magnetic transformer core, perhaps from the iron in the blood stream.

So basically it's a really rotten antenna that only radiates detectable signals near the blood vessels.

Put the 13 MHz ISM band on it and... voila! your arm is now a very inefficient crude NFC conduction conduit.

Sounds like a really dumb ham radio trick to me.

Sep 02, 2015
Like the ads for those absurd 'magnetic bracelets', Do not use if pregnant or have pace-maker'.

Make that 'dosing pump', too ?

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