Question about RFID tags, chips, etc.

Hello ATS techies.

Would one of you be so kind as to give me some advice about RFID tags? Specificially, is there an easy way to sweep for them and/or eliminate them? Other than prying open everything and then burning them when found that is.

Also, I'm curious as to whether there are any similar devices or technologies that do essentially the same thing as RFID in a different way.

Thanks in advance for any answers,

Silent thunder

[edit on 7/24/10 by silent thunder]

Are you talking about RFID chips being hidden in your home or what?

Originally posted by NightGypsy
Are you talking about RFID chips being hidden in your home or what?

Yes, sorry for the misspelling.

Hidden in a home, in a car, on products you buy, in documents you handle, in clothes, whatever.

reply to post by silent thunder


It depends on what sort of RFID you are looking for. There are several categories.

First, they are generally either h-field or e-field. Within those categories, you can have active, semi-active, or passive. Semi-active and passive of either type could be smart or dumb. They can fall into a number of discrete frequency bands, as well, for any of the types.

As standalone 'exotics' you could also have optic or time-domain ('sneaky wave'), but I've never seen those in civilian hands, and those are always active or semi-active.

Active or semi-active have batteries in. They're hard to hide, as the batteries will preclude them from being tiny, and they'll need occasional recharging or replacement, especially fully active tags.

Passive h-field tags can be quite small - the verichip is an example - you can get them down to the size of a rice grain. However, all h-field tags have very limited read distances, usually no more than a couple of feet, max. However, h-field tags have more power in the near field than e-field tags, and can be quite complex.

Passive e-field tags can be read at a fair distance, say up to 30 feet, or so. But they are 'stupid', and generally only return fixed serial numbers. E-field tags have noticeable antenna structures, even Hitachi's "RFID dust" requires an antenna structure something like a stick of gum. The part is small but the antenna is not. There is a mu-chip without an obvious antenna (HP has a variant on this) but they have very minimal read distances - maybe a quarter inch.

So what you have to look for depends on what you're expecting to be scanned with. If you're worried about stuff from the street, it's all e-field and you have to look for things large enough to have batteries in for active and semi-active, or with a fair sized antenna structure on them.

If you're worried about brush-pass scanning or interrogator loops hidden in door frames, that's something else - they have to be quite close or you have to pass through a reader loop, but h-field RFID can also be quite small.

reply to post by silent thunder


Alot of companies have been using the rfid chips/tags for years - they are essentially used to track inventory from point of production to sales outlet, not so much for who buys them and what they do with the product afterwards.

There are laws in some countries that the tags must be removed or switched off at point of sale, though this is difficult to police fully. Plus some companies think that by having tags remain in place, when an item is returned from a customer if it is faulty, then with one swipe of a scanner it's entire history can be tracked saving time and effort for the company. I.e. they can pinpoint where the problem may have occured in the production/warehouseing/distribution/sales line.

They have rfid chips masked as buttons, labels, or sewn into the hem of clothing for example. In other products, they are either hidden, or if not, may look like a small round bandaid made of polystyrene or similar material. As far as I know, there are not commercially made rfid chips available so small as to be difficult to find physically.

If they are not turned off or removed at point of sale, then they should be able to be picked up with a handheld scanner which may cost upwards of $600. I believe they generally operate on/emit similar frequencies so a handheld scanner, which can tune into different frequencies, should at least be able to get some sort of signal to determine if it is still active...but it may not neccessarily pick up the information within the rfid tag.

I had to do a consulting job on these tags, and met with many companies, though personally am against them; ultimately it was determined in my instance to steer clear of them.

Originally posted by cloudbreak

If they are not turned off or removed at point of sale, then they should be able to be picked up with a handheld scanner which may cost upwards of $600. I believe they generally operate on/emit similar frequencies so a handheld scanner, which can tune into different frequencies, should at least be able to get some sort of signal to determine if it is still active...

Neither sort of passive RFID emits anything at all. You can't find them with a scanner.

Heck, even when they're working, they don't actually emit a signal: h-field parts throw a load on and off the interrogator's output coil, and e-field parts change their reflectivity to the interrogator's radio signal.

You can't receive e-field signals with an h-field loop, nor could you receive h-field signals with an e-field antenna. So even if a scanner would work, and it won't, you'd have to have the right sort to match the tags you're looking for.

Of the sort with batteries in, semi-active tags don't transmit unless pinged. An active tag might transmit on its own at times and could be located with a simple frequency scanner with the right antenna type if so.

Optic and sneaky-wave tags won't be locatable by emission. They are pretty big physically.

Originally posted by Bedlam

Originally posted by cloudbreak

If they are not turned off or removed at point of sale, then they should be able to be picked up with a handheld scanner which may cost upwards of $600. I believe they generally operate on/emit similar frequencies so a handheld scanner, which can tune into different frequencies, should at least be able to get some sort of signal to determine if it is still active...

Neither sort of passive RFID emits anything at all. You can't find them with a scanner.

Heck, even when they're working, they don't actually emit a signal: h-field parts throw a load on and off the interrogator's output coil, and e-field parts change their reflectivity to the interrogator's radio signal.

You can't receive e-field signals with an h-field loop, nor could you receive h-field signals with an e-field antenna. So even if a scanner would work, and it won't, you'd have to have the right sort to match the tags you're looking for.

Of the sort with batteries in, semi-active tags don't transmit unless pinged. An active tag might transmit on its own at times and could be located with a simple frequency scanner with the right antenna type if so.

Optic and sneaky-wave tags won't be locatable by emission. They are pretty big physically.

Hmm maybe. But isn't the whole point of having an RFID tag the very reasoning that it can be scanned, picked up and identified? Maybe the passive tags don't emit a regular signal, but you still have to have a scanner/reader to identify the tag, otherwise there is a zero need for having the tag in the first place.

Honestly, I can't comment so much on the tech aspects of the e and h field type frequencies as I have not got any info in front of me, and it was about a year ago I did this, so just going on what I know, which may be limited compared to your knowledge on the various frequencies. I met with about 10 major producers of the tags - they all showed me their various tags, active and passive, the pros cons, and the scanners/reading equipment you use to identify them.

The very fact they are used in the first place is for the purpose and ability that they can be scanned. Some of the handheld scanners could be used at different frequencies, cost upward of $600, and are used to identify the rfid tags.

My impression was the cost-benefit ratio was a bit iffy, plus there is a public perception of the tags which isn't so good - not to mention laws in some countries that require them to be removed at point of sale; which could lead to legal/privacy issues should independent retailers or distributors fail to do this.

Originally posted by cloudbreak
Hmm maybe. But isn't the whole point of having an RFID tag the very reasoning that it can be scanned, picked up and identified? Maybe the passive tags don't emit a regular signal, but you still have to have a scanner/reader to identify the tag, otherwise there is a zero need for having the tag in the first place.

Well, you could pick them up with an interrogator, if you had the right sort, and the tags were amenable to being scanned.

I'm not sure what sort of thing the OP is worried about since the question was a bit vague. If OP is wanting to just find commercial tags, you need either an e or h field interrogator for the right frequency and make of tags. There are different types of tags, not all are ISO standard, so even if you get the gross type and frequency right, it may or may not respond if you don't know the protocol it's using. Note that this is not an issue for the store, because they will know what they're using by definition and will have the right readers for the tags they used. As a consumer, it's a bit more difficult since you DON'T know what they used and have to try more than one thing to cover the gamut.

There may be a universal e-field tag reader that tries all three major frequency ranges and the more common protocols. The ones I've seen were fairly specific to the tag, with the exception of ISO standard tags which are surprisingly uniform and will respond to pretty much any ISO interrogator of the right type and frequency. Most everyone uses ISO protocol tags now, but there's a few that aren't.

If the OP is worried about RFID tags that might be a bit less stock, the difficulty goes up by an order of magnitude, because you can be sure that someone applying a nefarious tag will also not be using standard ISO comm protocols, and the secret tag will not respond to an off-the-shelf interrogator.

reply to post by Bedlam


Maybe there is a misunderstanding of mere terminology on my part, but I would but the term 'interrogator' in the same class as scanner/reader. The more expensive, high tech tags mostly had the ability to be read with such handheld equipment as far as I know. I won't comment on the passive ones as I can't remember enough right now,

I think you though would perhaps know more than me what would be the best type of interrogator, or scanner/reader, that would be commercially available and is most likely to pick up the most commonly-used type of tags. I could look into the things I had to go over last year, over the next couple of days, but it maybe limited.

I think that is what the OP is asking, what sort of equipment is available to pick up rogue, forgotten, or dare I say, nefarious RFIDs. Which as you say, do come in various forms.

I was just coming purely from a business/logistics p.o.v. on the tags. I tried to find out the most powerful, plus the smallest etc tags and exactly what benefit they may bring in terms of cost benefits. Certainly from my perspective it had zero to do with anything beyond logistics. And that is purely from what I can gather is the prime reason most companies would use them in the first place; to track their goods globally through the production/distribution chain, and not for 'spying' on or tracking customers.

I'm not a NWO shill, nor am I personally pro these tags in any sense, but the one thing I could say is for many companies they are actually far from being used for anything sinister. Many use them, even all your major UPS/Fedex type companies on every single package sent, but if you have any rogue tags lying around the house somewhere, my understanding is to be read, or interrogated, you have to be so close to the tag as to render them useless. Unless of course there is advanced technology in play here I am unaware of.

However, I could still see the need to identify unknown tags as technology advances. Say you did have a tag embedded in your clothing or a product you carry round with you...maybe readers at certain locations will get to the stage that they can identify various types of tags (if not removed) as you walk into a shop, and target you on certain data. Who knows.

reply to post by cloudbreak


I would bet there are probably tri-band e-field ISO tag readers that would read most WallyWorld tags, along with most other shelving/stocking tags.

As long as you don't run into wonky older parts like older gemstar or TIris tags that don't use ISO protocols, you'd likely find most distance read tags.

The really tiny ones though, are generally h-field tags. The good thing is they're not distance readable.

And the purposefully non-stock ones you will only find by direct inspection.

I had thought by 'scanner' you meant something like a sniffer or spectrum analyzer. We used to use these to check for active bugs.

You know, though, the other thing we used to use to scan for bugs is a non-linear junction detector. If you had a 'clean room' with no other electronics in, and you put the stuff to be scanned in there, you could find pretty much any sort of electronics hidden within, including nefarious tags. Hell, you can even find a sneaky-wave tag that way, if you somehow managed to miss it by direct inspection.

They're sort of pissy to use, you can pick up false readings from odd bits of metal, so you'd have to be careful about zippers and the like. Takes some training, it's tedious as hell, costs about 20K, unless they've come down.

reply to post by Bedlam


Ok thanks for clearing that up - you pretty much answered the OP's question in more detail than I could have.

For the smaller, H field tags...do you think a generic off-the-shelf interrogator able to read or ping these tags would be able to pick up these type of rfids in general? I know you have to be very close to them to read them, but in time as tech advances they will likely get more powerful I guess.

Yes, by scanner/reader I was talking about the specific equipment used to identify/read the tags, which was available in both gate format (like two gates you pass through) or handheld. From memory I think a couple of the producers referred to them as the scanning equipment, but now that I think about it 'interrogator' is familar and no doubt what some used as terminology too. But yeah...I meant it in the same sense.

Originally posted by cloudbreak
reply to post by Bedlam

 

For the smaller, H field tags...do you think a generic off-the-shelf interrogator able to read or ping these tags would be able to pick up these type of rfids in general? I know you have to be very close to them to read them, but in time as tech advances they will likely get more powerful I guess.

I'm pretty sure they'll never be distance readable at all.

There are a number of issues. One is that the power density available to run the tag goes down as the sixth power of the distance, which is really bad.

They also have a hellish signal to noise ratio issue. And they're strictly near field, so even if you had the other issues licked you still can't read them in the far field.

I think the best I've ever heard of was about 24 - 28" using a custom built definitely non-FCC compliant rig with DSPs doing correlations to pick out the signal from hundreds of re-reads.

Gret stuff, thanks everyone for your quick and helpful answers.

This is not really an area I know too much about, so this has been very interesting.

I assume in my paranoid ATS way that there are probably a number of other types of tracking technology that I/we have never heard about, too... but I'm not going to let it keep me up at night, anyway.

Thanks again.