EPC class 2 future implant?

Keeping an eye on the RFID/NFC space and working as an engineer I’ve noticed that this new gen of tags is popping up that has good distance reading, high security, wide functionality, with features that seem like they’d work well with a number of technologies. The spec is for 40-50 years of data integrity instead of 20, AES-128 encryption. Commercial tags can get up to 16 ft range totally passive, in a back of hand or forearm form factor through a layer of skin an implant could probably push 5-7 ft range.

While I’m planning a FlexDF2 for access control (and hopefully a Titan on the way soon), home security, device security, the range requires interacting with a reader pretty directly. There are a lot of applications where it’d be cool if I could just walk into a room and the reader effortlessly picks the tag, flips the lights, or lay down in bed triggering lights off, locks set, etc. would be both cool and enable a lot of cool projects. Is there any interest/plans to find a good chip of this new gen spec and make an implant of it?

UHF tags?

As Satur9 was suggesting, these are UHF tags. Amal talks about it a bit here:

Essentially UHF implants are likely not feasible, due to interference from the skin/flesh.

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Yes, they work at 860 MHz - 960 MHz, also described by ISO/IEC 18000-6:2010 spec I believe. There are a lot of the class 1 tags out there, and class 1 gen 2 tags, which are great for security but don’t have much application space. I’m not finding a ton of direct sale of chips or well promoted chips class 2 yet, but there are a ton of cards, fobs, tags out there alread

When I get a chance in a couple months I’ll test this out and check range reduction on a standard card from a couple mm of brown sugar. They tend to need pretty small antenna though, so something the standard size with a flat antenna array would be a lot bigger pickup area than those 16 ft range tags use, if we’re at a 20 ft range antenna through 75% attenuation that’d still be a comfortable 5 ft. Sounds like this is going to take some work, design, testing on my part to see if it can be done in a worthwhile way. I’ll update in a few months when I’ve had some time to dig further.

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Best in mind, a standard card is going to have much much better range than something implantable it may not be a fair comparison

I think you’ll experience more than 75% attenuation. Here’s a source for the maths on penetration depth. Here’s some screengrabs from there

Screenshot_20210623-145543

Screenshot_20210623-145603

Here’s me replicating their example calc of 2.5m penetration depth of a 10kHz signal in salt water
Screenshot_20210623-150127

And here’s a similar calculation for 860MHz. You would get about 8.6mm penetration depth. That’s cutting it pretty close. It maybe might work at all.

Screenshot_20210623-150450

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I mean if it’s behind 2-3mm of skin/flesh, that’s less than half the penetration depth. It’s not promising as that’s the best case end of the range, but it’s still not disqualifying and worthy of some testing. I’m in the middle of a move that’s tapping my budget pretty hard but once I’m settled in at the new place I’ll pick up tags similarly sized to an implant, set the meat slicer to 2 then 3 mm on some ham, see what kind of attenuation I get. Best way to find out is to test, right?

I may have access to a bunch of EPC class 2 tags and readers soon for a work project & was just wondering about this. I’ll do some testing if I get the chance

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