For detecting RFID chips, the tag should be identified first because some mobile phones can read NFC and HF tags at a frequency of 13.56 MHz. Different frequencies are needed for LF tags, animal microchips, and UHF warehouse tags. If a reader uses an inappropriate frequency, no response will come from the tag.
This guide describes ways of identifying RFID chips, selecting appropriate readers, checking tags, and detecting possible sources of reading failure. It also describes the limitations of mobile phones, specialized RFID equipment, and influences on detection distance.
What Does It Mean to Detect an RFID Chip?
The detection of an RFID chip means establishing that a chip reacts to a particular reader. There can be other operations, like reading data, identification, location, or verification in relation to an item’s records. Each operation plays a different role in the RFID process.
- Detect:Establish that the chip .
- Read:Read the UID, EPC, or TID of a chip
- Identify:Identify the chip with respect to an item.
- Locate:Locate the chip in a certain space.
- Verify: Compare the chipwith product records.
How Does an RFID Reader Detect a Chip?
RFID reader transmits radio waves via the antenna and waits for a reply. Tags that use LF and HF frequency ranges work by near-field coupling. Passive UHF tags transmit data via back scatter technology. The reader analyzes the response and notifies the system about it.
Identify the RFID chip Types Before You Scan
The reader to use depends on the RFID technology and RFID tag standard.
| RFID Technology | Frequency | Reader |
| LF | 125 kHz | Compatible LF reader |
| LF | 134.2 kHz | Animal microchip reader |
| HF | 13.56 MHz | Compatible HF reader |
| NFC | 13.56 MHz | NFC phone or reader |
| UHF / RAIN RFID | 860-960 MHz | UHF reader for the local frequency band |
| Active RFID | System-specific | Receiver that matches the technology |
Look at the tag, card, data sheet, quote, or previous purchase history for 125 kHz, 13.56 MHz, NFC, UHF, EPC Gen2, or the chip type. The application context is helpful as well. The shape of the RFID tag doesn’t tell much about the technology used. Same-looking cards may have different chips or communication technologies inside.
Can a Phone Detect RFID Chips?
RFID chips at a frequency of 13.56 MHz can be recognized by phones with a built-in NFC chip. Switch on NFC, install a tag-reading application, place your RFID tag near the NFC region of the phone, and slide it slowly so that the tag can be read by your phone. The supported information will be displayed in your application.
LF and UHF tags require dedicated reader hardware to be read.
How to Detect RFID Chips Step by Step
Step 1 – Define Your Detection Goal
Identify the aim before determining the hardware involved. Scanning for one single tagged object is different from scanning for 300 cartons that might be on a particular pallet. It’ll be important to identify the specific aim, whether reading the tag, identifying its unique identifier, counting stock, or identifying one missing item.
Step 2 – Estimate the Frequency
Check if there are any tag specifications, like tag label, card model, product specification, quotation, or supplier information, regarding the operating frequency or chip used. Where this isn’t available, consider the application. Most warehouse labels use UHF, while access cards card use many LF or HF technologies. Many animal microchips use 134.2 kHz LF.
Step 3 – Select a Compatible Reader
Before testing the tag reader, examine the specifications, including operating frequency, tag standards used, maximum reading distance, type of antenna, even if the reader is portable or stationary, number of tags it can support, and if SDK/API is supported. If it’s an EPC Gen2 or ISO 18000-63 tag, select a reader that supports that tag standard.
Step 4 – Test a Known Working Tag
Test a working tag of the same tag type a number of times and observe its output. This will determine the reader and configuration work with that tag. Proceed to scan the unknown tag using the same configuration.
Step 5 – Scan From Different Positions
If the first scan isn’t working, change the position of the tag. Get closer to the tag, turn the tag around, change the angle of the reader, or scan from the other side of the object. The orientation is important in many UHF tag scans.
Step 6 – Check the Data
Scan the tag multiple times and check for consistency. Check if the right identification number is used for the tag you want to test. Many HF tags use the UID or serial number as identifiers. UHF EPC Gen2 tags use EPC and TID memories. In the warehouse, verify the right EPC for the right product or equipment in your system.
Step 7 – Test It on the Real Product
Perform the final test in the real environment. Attach the tag to the box, bottle, equipment, or pallet, and perform the scan at the necessary scanning distance and speed of the moving item.
Which RFID Detection Device Do You Need?
Choose the right reader for the job.
| Task | Best device |
| Checking an NFC label | NFC phone/NFC reader |
| Read a 13.56 MHz card | HF reader |
| Read a 125 kHz card | LF reader |
| Checking an RFID pet chip | Animal scanner (134.2 kHz) |
| Checking warehouse inventory | Handheld UHF reader |
| Reading items in a doorway | Fixed UHF reader with antennas |
| Scanning items on a conveyor | Fixed reader with antennas |
| Installing RFID in a machine | RFID reader module |
To check stock inventory in a warehouse, use a handheld UHF reader that doesn’t need to aim at every individual tag. A warehouse doorway uses fixed antennas to generate a read field and detect moving cartons. The reading speed should match the conveyor speed.
Why Can’t My RFID Reader Detect the Tag?
A missed scan might caused by:
- Inappropriate RFID frequency: A UHF RFID label for logistics purposes requires a UHF reader, not an NFC phone.
- Unmatching RFID tag standard: Tags operating at the same frequency may use different communication standards.
- Too long distance: The energy supplied to a passive tag must be strong enough; move the tag nearer and scan.
- Improper angle: Rotate the tag or move its antenna.
- Metal: Standard UHF tags usually operate poorly on steel. Use on-metal/anti-metal RFID labels for tools, racks, machines, and metal containers.
- Water: Water decreases the working range of many UHF RFID labels. This applies to drinks, fresh foods, cosmetics, and wearable tags.
- Damaged tag: Cut antennas or broken chip connections prevent the tag from responding.
- Reader parameters:Power level, scan time, filters, and tag population settings influence the read result.
- Interference between readers: Overlapping reading areas result in stray readings beyond the target area. Poorly coordinated UHF readers can cause interference.
- Software filters: Software filters exclude tags that were first read by the hardware; look into your reader logs before replacing any device.
Test one parameter of your configuration at a time and scan.
How Far Away Can an RFID Chip Be Detected?
The range is determined by the RFID technology and configuration used. NFC is configured to read tags in close proximity to the phone or reader. An LF RFID tag is intended for short-range reading. Passive UHF usually offers a distance of a few meters depending on conditions, and active RFID can have different ranges, too.
Tag size, antenna configuration, reader power, mounting surface, orientation, and surrounding materials all influence the final distance. A passive UHF tag that has a good range in an open area won’t have the same range when placed on a steel shelf.
In warehouses, read rate is more important than read range. If a gate can read 99 out of 100 tagged boxes passing through, the read rate is 99%.
How to Find or Locate a Specific RFID Tag
A portable UHF reader used to find a particular item within a warehouse or storage facility. Choose the desired EPC, then simply move around the area and observe the RSSI value. A stronger signal helps in determining the direction of the tag. Metal shelves, walls, and surrounding objects affect the signal measurement.
In case precise positioning is required, special locating systems can be used. They include RFID with multi-antenna/direction-finding technology, BLE, and UWB technologies. Active RFID is capable of supporting locating technology.
Can RFID Detection Verify Product Authenticity?
RFID detection proves that the tag responds, but product authenticity is an additional process. It’s possible to duplicate the same EPC on multiple tags; thus, the authentication procedure involves the EPC along with other credible data.
Use the EPC, TID, serial number, and backend data for authentication. You can opt for RFID chips that support cryptographic authentication.
Common RFID Detection Myths
- Every mobile can detect any RFID chip.
Mobiles read only compatible NFC and compatible 13.56 MHz HF tags.
- Tags send signals all day round.
Passive tags are activated by energy supplied by a suitable reader.
- Any 13.56 MHz tag is readable with any NFC mobile.
No. The mobile should be suitable for reading the specific RFID technology and communication protocol.
- RFID works normally on metal.
Standard UHF labels can be unreadable due to metal surfaces. There are special on-metal or anti-metal labels intended for application on metal surfaces.
- UHF RFID is readable from a distance of 10 meters.
No. Distance depends on the RFID tag, RFID antenna, reader power, mounting surface, and work area.
- RFID provides a precise GPS position of a tag.
No. A standard RFID reader gives information about the tag and signal instead of GPS coordinates.
A similar rule applies to the detection of RFID chips implanted into the human body. Implantable RFID tags usually work in the LF frequency band. Suitable scanners are needed to read RFID tags. Ordinary LF implants are detected with the help of compatible LF scanners, not mobiles.
In a possible medical implantation, please contact your healthcare professional.
How to Choose the Right RFID Detection Solution
- Make sure that the reader matches the frequency range and communication protocol.
- Consider the read range, number of tags, mounting location, and movement of the object when selecting the antennas.
- For UHF systems, consider the operating frequency band and the maximum reader power permitted in the country of installation.
- In bulk purchase, test all the components, including the reader, antennas, tag, item, and software, in the real environment. This will show you poor read results, bad tag placement, stray readings, and hardware compatibility issues.
Frequently Asked Questions
Can a phone detect all RFID chips?
No. The NFC chip inside phones detects NFC tags and compatible HF tags at 13.56 MHz. LF and UHF require a dedicated reader.
Can an iPhone detect UHF RFID tags?
No. The built-in NFC chip in an iPhone cannot detect UHF RFID tags. It requires an external reader.
What device detects 125 kHz RFID chips?
Use a 125 kHz LF reader compatible with the tag’s protocol. Both the frequency and protocol should match. Different LF systems use different protocols.
Can RFID tags be detected through metal?
Metal interferes with RFID signals. An RFID tag designed for on-metal use will function on steel or other metals. However, a metal shield will block the signal.
How far away can RFID chips be detected?
RFID reading distance depends on the type and configuration. NFC is designed for very close-range detection, and LF is short-range. Passive UHF will typically work up to a few meters, depending on the conditions. Active RFID depends on the system.
Why does my reader detect some tags but not others?
Most missed detections happen because of the distance, angle, mounting surface, damage, or incorrect reader settings. Filters in the reader’s software might skip tags detected by the hardware. Reader log files will tell whether it ‘s a problem with the hardware or software.
Can a damaged RFID tag still be detected?
Yes, provided the antenna and chip connection are still operational. Small damage to the antenna affects its response range. A damaged antenna connection will prevent the tag from responding.
Can a locked or killed RFID tag be detected?
A lock will allow certain commands to be received. The lock doesn’t turn off the tag; it locks down certain memory. A properly killed UHF Gen2 tag won’t respond anymore.
Can an RFID reader locate the exact position of a tag?
The reader can narrow down the search area. UHF handheld readers use signal strength as a search tool, but not for exact distance measurement. Exact positioning requires specific hardware.
Is NFC the same as RFID?
No. NFC is an RFID technology that works at a frequency of 13.56 MHz over short ranges. RFID technologies also include LF, UHF, and active systems.
Does detecting an RFID tag prove that a product is authentic?
No. A tag’s successful response doesn’t mean the product is genuine. Authenticity requires either authenticated product information or another kind of check. The same EPC doesn’t make a product genuine.
Conclusion
If you need an RFID reader for any purpose, including inventory, asset tracking, production, and access, JLTRFID will help you select the most suitable reader that fits your RFID tag type and operating conditions.
Notify us the RFID frequency, range, material of your product, and number of scans needed, and we’ll provide reader selection and a testing sample before a bulk order.
