RFID Tags In & On Metal Possibilities and Limitations

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1 The Trusted Source for Secure Identity Solutions RFID Tags In & On Metal Possibilities and Limitations September 9, 2015

2 Transponders for Applications in Metal Environment Metallic environment (negatively) affects RFID performance The higher the frequency the more affected LF is least-, HF more - and UHF most-affected, requiring special design Some RFID tags can be embedded in metal or designed to work on-metal 2

3 Reasons to embed RFID Tags in Metal The easiest way to tag metallic objects is to attach a tag designed for on-metal use by screws, rivets, glue or welding The desire to embed tags into metal arises when some of the following advantages are needed: Main advantages: The RFID component is fully protected from the environment, especially against heavy impact or scratches The tag is not visible and cannot be removed (if it is embedded into the asset itself instead of being "just" a tag with metallic housing) The surface of the tagged asset does not change compared to a non-tagged asset (if the tag is embedded into the asset itself). This is relevant for some use cases like engine parts or tools. Also cleaning the assets is easier Main disadvantages: Design and production process of asset changes to embed the RFID tag Limited options for retrofitting in-metal (either drill a hole into the asset or use on-metal tags to be affixed outside) UHF/ long read ranges are not suitable for in-metal use (on-metal only) 3

4 Technology Standards 4

5 CHIP RFID System Basis Reader Tag Reader Creates a magnetic field to power up the tag Transmits data by amplitude modulation Receives data from transponder and demodulates them Transponder Sends its data by modulation (ASK/PSK/FSK) Stores received data in local memory (EEPROM / FRAM) 5

6 RFID System An RFID systems will achieve the maximum working range in a clean environment (without electrical noise and without metal in the near field) The reading performance of each application is mainly depending on the reader design, but also on the transponder characteristics: size and shape of antenna (ferrite or air coil) inductivity of the transponder s antenna Q value of transponder antenna accuracy of tuned SRF 6

7 What is the Influence of Metal? In metal environment the reading performance is reduced. RFID system will be influenced by metal is placed in the magnetic field generated by the reader. The magnetic field penetrates into the metal and causes eddy currents on its surface and creates energy losses. As a result, the magnetic field will weaken and the reading distance will be drastically reduced. In addition to the eddy currents, the SRF of the tag is detuned depending on the proximity of the tag to the metal, which is also a factor of loosing performances if this is not taken into consideration in the tag design. 7

Influence of Metal Tag SRF detuning because of metal The metal environment close to the transponder system shifts the SRF of the tag to another value; in the worst case the SRF could be outside of

8 Influence of Metal Tag SRF detuning because of metal The metal environment close to the transponder system shifts the SRF of the tag to another value; in the worst case the SRF could be outside of the bandwidth and would not allow any reading. U/ V Umax U-3dB The bandwidth B determines the frequency range that allows data transmission. A tag with a high Q gives better reading performance. However a slight shift of the SRF due to metal will reduce drastically the reading distance. A tag with a lower Q will be less influenced by the metal MHz (HF) technology is more influenced by metal compared to 125 khz (LF). LF can be completely enclosed in metal, HF needs to have a small gap between transponder and outside. SRF B 1 f / khz 8

CHI P How to Reduce the Influence of Metal? Use of a shielding between the metal and the RFID system. Reader TAG Ferrite or Alloy or Mu Metal Metal Plate IN Tag 200 13.

9 CHI P How to Reduce the Influence of Metal? Use of a shielding between the metal and the RFID system. Reader TAG Ferrite or Alloy or Mu Metal Metal Plate IN Tag MHz Metal Mount, embedded ferrite shielding Logi Tag 121 Metal Mount with ferrite shielding on the back Use of a Spacer between the metal and the RFID system. IN Tag MHz or UHF Metal Mount, embedded spacer shielding PolyTag 340 mm with embedded spacer shielding 9

10 LF / HF Disc read range affected when on-metal LF INTag 300 reaches >90% at ~6mm and >50% at ~2mm HF INTag 300 reaches >90% at ~30mm and >50% at ~5mm distance from metal 10

LF 125 / 134.2 khz in metal The low frequency technology 125 / 134.

11 LF 125 / khz in metal The low frequency technology 125 / 134.2kHz in metal In some conditions Low frequency technology with HID Glass Tag can be used inside metal. Pictures by Hanex Ltd., The low magnetic resistance of the ferrite core used inside HID Glass Tag concentrates the magnetic flux at both ends of the ferrite. Even if there are losses due to eddy currents in the metal, the remaining energy is still strong enough to power the tag. 11

cover. Pictures by Hanex Ltd., www.metal-rfid.

part, a micro slit is given between both parts.

12 LF 125 / khz in metal The Glass Tag can still be read through a metal cover. Pictures by Hanex Ltd., Due to the roughness of the metal cover and the solid metal part, a micro slit is given between both parts. The magnetic flux penetrates this super thin gap and can still power the tag with sufficient energy. Besides the penetration through the slot, the low magnetic resistance and the high electrical resistance is also one reason for the functionality of the tag in this environment. 12

13 Examples of Tags into Metal A LF glass tag 13mm inserted into a massive block of metal with a drilled hole can be read through a wall of approx. 0.9 mm thickness Pictures by Hanex Ltd., 13

14 Examples of Tags into Metal In harsh environment, a LF tag can be entirely covered with metal and a standard reader will still be able to read the information. Pictures by Hanex Ltd., 14

15 Examples of Tags into Metal When the tag needs to be inserted deeper than 0.9 mm or it is an HF tag, a slot on the side of the metal box does help to supply the tag with energy. Pictures by Hanex Ltd., 15

16 Examples of Tags into Metal To tag standard tools, e.g. injection tools, a simple cavity can be made into the tools to insert the tag in. The tag is fixed into metal with epoxy glue. Pictures by Hanex Ltd., Application for ASK type of tags patented by Hanex Ldt. 16

17 Examples of Tags into Metal Pictures by Hanex Ltd., 17

18 Examples of Tags into Metal (LF ClearDisc) Pictures by Hanex Ltd., 18

19 Examples of Tags into Metal Identification of metal plates: The LF glass tag is inserted into a special cavity. Pictures by Hanex Ltd., Application for ASK type of tags patented by Hanex Ldt. 19

20 Examples of Tags into Metal The performance depends highly on the tag and type of reader used. Small practical trials and validation by the integrator is required to ensure optimum performance. Pictures by Hanex Ltd., Application for ASK type of tags patented by Hanex Ldt. 20

21 Examples of Tags into Metal Glass tag in bicycle lock Pictures by Taiwan Cable 21

22 The Trusted Source for Secure Identity Solutions UHF on-metal Tags

private areas Excellent robustness to temperature and impact (IK09) Works on metal and any other materials

23 InLine Tag Ultra Family Highlights Monza 4QT excellent performance / size (8m) 128 bit EPC, 512 bit user memory incl. private areas Excellent robustness to temperature and impact (IK09) Works on metal and any other materials Supports all frequencies (US, EU, JP) To screw or weld with optional steel ring Patent pending 3D antenna (orientation independent) Slim option IP68 + IP69K Waterproof incl. High-pressure/temperature 23

428 F/220 C - 1h) Flame resistant UL94HB, UV resistant (ISO 4892-2) Optional high temperature sticker

24 HID: IronTag 176 Highlights On Metal only tag, very thin Optimized for local frequency bands EU or US Excellent size/performance: Read range >4 m Patent pending on antenna Peak temperature (356 F/180 C - 400h or 428 F/220 C - 1h) Flame resistant UL94HB, UV resistant (ISO ) Optional high temperature sticker Toughest waterproof standard - IP69K Compatible to aerospace standards ATA Spec 2000 and SAE AS5678 Dimensions: 53x23x6.8mm 24

25 Mounting UHF Tags in Metal Embedding a UHF tag in metal has stronger physical limits than LF or HF, the UHF antenna must be exposed to free air E.g. placing an IronTag 176, 7 mm deep into a metal cavity has the following effect 25

26 HID IronTag 206 Highlights On metal only tag, very thin and lightweight (9.9 g) Monza X 2k/8k UHF chip or 915 MHz (128 bit EPC, 2176 or 8192 bit user memory) Fixation via screws, rivets, clamps or glue (sticker) Excellent size/performance: Read range ~2.5 m Peak temperature (428 F / 220 C - 10h, 356 F / 180 C - 600h) Highest flame resistance UL94V0, UV resistant (ISO ) Optional very high bond adhesive sticker 3M 9473 Alternative fixation via screws or clamps Waterproof IP67, Impact resistance - IK07 Dimensions: 33x30x5.8 mm Altitude: up to ft / m Compatible to aerospace standards (ATA Spec 2000 and SAE AS5678) 26

on-metal, and broadband when offmetal Read range on metal: ~6 m (19.6 ft), off-metal: 8 m (26.

27 HID InLine Tag Plate Highlights Extremely thin and tough on/off-metal UHF plate Plenty of room for visual marking via laser engraving and/or sticker Monza 3 chip - 96 bit EPC (EU) or Monza 4E chip bit EPC (US) Optimized for use in EU or US on-metal, and broadband when offmetal Read range on metal: ~6 m (19.6 ft), off-metal: 8 m (26.2 ft) Waterproof - IP69K, Impact resistant: IK06 Custom non-abrasive laser engraving and sticker possible for visual backup Dimensions: 120 x 68 x 3.7 mm 27

Keg Tag UHF Highlights On metal only tag, curved to fit gas bottles and kegs (smaller radius than InLine Tag Ultra Curve for compartments like gas bottles) Monza 4E UHF chip (496 bit EPC, 128 bit

28 Keg Tag UHF Highlights On metal only tag, curved to fit gas bottles and kegs (smaller radius than InLine Tag Ultra Curve for compartments like gas bottles) Monza 4E UHF chip (496 bit EPC, 128 bit user memory) Optimized for local frequency bands EU or US Excellent size/performance: Read range >6 m Operating temperature (-40 to +80 C) Waterproof IP68, IP 69K Impact resistance - IK09 Dimensions: 33x40x8.5 mm 28

HID: IN Tag 500 UHF or UHF on Metal What it differentiates it from other UHF tags

available as HF on metal version Electrical performance of tag affixed on 10 mm

5 mm Remark: Performance decreases by 10-20 % if tag placed on Teflon/Plexiglas/PC

29 HID: IN Tag 500 UHF or UHF on Metal What it differentiates it from other UHF tags (ours or competitors): Circular form factor. Small form factor. Center hole for one-screw mounting. Complete the successful InTag line of product Resist to temperature up to 140C Also available as HF on metal version Electrical performance of tag affixed on 10 mm thick PET/ABS Dimensions: Ø50mm, 3.5 mm Remark: Performance decreases by % if tag placed on Teflon/Plexiglas/PC material with thickness 10 mm., Performance increases by 10-20% if placed on Glass with same thickness. Performance decreases by same amount if thickness decreases by half. For any of these materials. 29

30 Questions and Answers

31 hidglobal.com/rfid

Physics of RFID. Pawel Waszczur McMaster RFID Applications Lab McMaster University

Physics of RFID. Pawel Waszczur McMaster RFID Applications Lab McMaster University 1 Physics of RFID Pawel Waszczur McMaster RFID Applications Lab McMaster University 2 Agenda Radio Waves Active vs. Passive Near field vs. Far field Behavior of UHF fields Modulation & Signal Coding 3