RFID applications: logistics, locating and ticketing
Passive or active: two kinds of RFID
Both methods read without line of sight. The difference lies in the power source: passive transponders are powered by the reader, active ones have their own battery. Range, price and use follow from that. You'll find LF, HF and UHF compared on the RFID page.
| Passive UHF RFID | Active RFID at 2.4 GHz | |
|---|---|---|
| Power | from the reader field | own battery, usually lasting several years |
| Range | up to around ten metres, depending on reader, antenna, label and surface | several dozen metres, considerably more with some systems |
| Form factor | label, inlay, hard tag | encased transponder to screw on or attach |
| Price per transponder | a few cents for labels | considerably higher, but reusable |
| Typical use | goods receipt, shipping, stocktaking, load carriers | locating, vehicle access, containers in circulation |
UHF RFID: many objects in a single read
UHF RFID is the method for warehouses, shipping and production. One reader captures every tag in the field at once, even inside closed cartons.
Tags are read to the EPC Gen2 standard (ISO/IEC 18000-63). It ensures that labels and readers from different manufacturers work together.
At the gate or with a handheld reader, all tags are captured at once instead of scanning each carton individually.
Metal reflects, liquid absorbs. On-metal labels and hard tags are made for this. A test with your material shows which label fits.
RFID printers write the chip, verify it and print plain text and barcode on the same label.
Active transponders at 2.4 GHz: locate, not just capture
Active transponders transmit on their own. That gives them a longer range and makes them suitable for anything that moves around a site.
Vehicles with a transponder are recognised at the barrier or gate. Access is granted and logged automatically.
Mesh boxes, forklifts or special containers report as soon as they enter or leave a zone, outdoor storage included. That cuts search times and shrinkage.
With several receivers, you can determine which zone a transponder is in. Where a Wi-Fi network is already in place, it can be used for locating as well.
The shorter the interval, the more precise the data and the shorter the battery life. Both are matched to the process in the project.
RFID in logistics: from goods receipt to the return loop
RFID pays off wherever items are counted, searched for or keyed in by hand today.
The delivery passes the gate, the tags are read and matched against the advance shipping notice. Discrepancies show up immediately, not at the next stocktake.
Storage locations carry RFID tags, and a reader on the forklift fork recognises the location and books the goods to it. The goods end up where they are booked.
With a handheld reader at the shelf, stock is counted without touching every item. Inventory stays accurate because it can be checked more often.
During loading, the system checks that the right goods are on the right vehicle. The read becomes the posting in the ERP.
Returnable containers and pallets are captured at every handover point. You know where each load carrier is and who had it last.
More on the blog
RFID ticketing: cards and wristbands for access and payment
At events, leisure facilities and on company badges, RFID replaces the paper ticket. The chip carries the authorisation, and the turnstile or terminal checks it in a fraction of a second.
Ticketing and access usually use HF RFID at 13.56 MHz, compatible with NFC. Waterproof wristbands are available for pools, saunas and gyms.
Card printers with an encoding module print the card and write the chip in one pass. Print and authorisation always match.
One medium for entry, working time at the terminal and payment at the bar. Lost cards can be blocked centrally.
Where hands need to stay free, for example in vehicles, UHF or active transponders read at a distance are used.
From our projects
Four examples of how RFID simplified a specific process for our customers.
At a Swiss construction company, every machine and tool carries a transponder. At issue and return, the tool and the badge are read and matched, and defective equipment is recorded straight away.
For a pharmaceutical company, every container carries an HF label. Anyone taking something logs on with their badge, and the scale books withdrawal and return by weight. The solution paid for itself within a few months.
A cleaning contractor uses concealed HF transponders to prove who cleaned which room and when. The mobile terminal reads the transponder on site and sends the data straight to head office.
For a major ticketing company, mobile handhelds at the entrance check paper, print-at-home and RFID tickets with a single device.
How your RFID application comes together
Every application goes through the same five steps. That avoids costly surprises once it is running.
Where do mis-shipments, searching, capture errors or late postings cost money today? We set implementation and operation against that, so it is clear early on whether and when RFID pays off.
Where, when, how much and why: we follow goods and data flows and check whether suppliers and customers can be included through standards. Sometimes it turns out that the process works better without extra technology.
On site, we look for interference from machines, radio and forklifts, check materials and distances, and decide where reading is fixed or mobile, which frequency and form factor fit and which interfaces are needed.
A pilot runs for several days with real data at the most difficult read point. Roll-out and acceptance follow only once it convinces.
For operation, we agree responsibilities, response times, training and spare parts. OPAL takes care of service and maintenance.
Frequently asked questions
What is the difference between passive and active RFID?
Passive transponders have no power source of their own and are powered by the reader. They are inexpensive and read up to around ten metres. Active transponders have a battery, transmit on their own and reach considerably further. They suit locating and vehicle access.
How far does UHF RFID read?
With passive UHF labels, up to around ten metres is possible. The actual range depends on reader, antenna, label and surface. A test with your objects gives a reliable answer.
Does RFID work on metal?
Yes, with on-metal labels or hard tags built for the purpose. Standard labels placed directly on metal read poorly or not at all.
Which frequency is used for ticketing?
Cards and wristbands mostly use HF at 13.56 MHz, compatible with NFC. For access at a distance, for example for vehicles, UHF or active transponders are used.
Can RFID data be connected to our ERP?
Yes. The read is passed to your ERP or warehouse management system as a posting via an interface. We clarify the right connection in the project.