Trying to understand if with current capabilities of Bluetooth 4.0 / Smart / BLE, is it possible to detect a passive RFID TAG, within a very short range (less than 5cm).

New phones both Android/iOS are to abandon NFC as far as I know, so does this mean that Passive tags are just no longer supported on these phones?

To be more precise: I am not looking for anything fancy.. In fact I just need to be able to detect the presence of one passive tag. No security or anything more complex.

Also, not to imply that this question regards specifically existing TAG product, also it would be nice if there is. I am willing to develop a new circuit, if that's possible...


closed as unclear what you're asking by Andy aka, Daniel Grillo, placeholder, Matt Young, Joe Hass May 20 '14 at 13:29

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  • \$\begingroup\$ What specification of tag? \$\endgroup\$ – Andy aka May 20 '14 at 8:54
  • \$\begingroup\$ The tag is as small as it can get, just without any power source. \$\endgroup\$ – rub May 20 '14 at 8:55
  • 1
    \$\begingroup\$ That is not a specification. \$\endgroup\$ – Andy aka May 20 '14 at 9:03
  • \$\begingroup\$ See updated question: The closest thing that I have to specification would be a standard RFID (or other?) tag card, slimmest as possible, and powerless. The reader is a cellular phone: iOS/Android primarily, which may have NFC, but not on all brands. NFC is phasing out, so I am looking for a bluetooth 4.0 BLE solution. \$\endgroup\$ – rub May 20 '14 at 9:32

RFID and BLE are two very different technologies, so no, you can't do that.


There are already BLE devices that works somewhat like RFID or NFC tags. These are called beacons. One specific technology is iBeacon developed by guess who :)

Beacons work by sending BLE advertisement packages. These packages can contain some user data.

I've recently developed a device that includes battery voltage info in the advertisement packets, so you don't even have to connect to it just to check on the battery level.

Take a look at Bluegiga's BLE112 / BLE113 devices and related development / breakout boards. They make BLE development super easy.

If you want to create a tag that can be seen from a short distance, you can set some arbitrary advertisement data that you can recognize, and set the radio tx level very low, so it can only be seen from like 10 meters.

  • \$\begingroup\$ Hi! thanks for the reply, but does it still imply that you can create a batteryless device? I am to understand if such a product is conceivable .. \$\endgroup\$ – rub May 20 '14 at 10:01
  • \$\begingroup\$ No, Bluetooth Low Energy beacons need a battery, but they consume very little power. (Hence the name) A BLE beacon can run from a coin cell for months or years. You can build a circuit that consume so little power that the battery will expire rather than running out of juice. \$\endgroup\$ – netom May 20 '14 at 10:14
  • \$\begingroup\$ Ok, that sounds promising :) But is there a battery which could last for considerably long time, and still be slimmer than standard coin cell battery. My intention is to develop a product which is maximum 2 mm thick, so a 3 mm thick battery is considered huge.. \$\endgroup\$ – rub May 20 '14 at 10:23
  • \$\begingroup\$ Yes, there a quite a number of solutions already. We considered these in one of our upcoming products: powerstream.com/thin-lithium-ion.htm . These are LiPo-s, you probably need 3V lithium cell like this: ultralifecorporation.com/be-commercial/products/thin-cell \$\endgroup\$ – netom May 20 '14 at 10:45

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