BARCODE VS RFID – RELATIVE BENEFITS
1. LINE OF SIGHT ISSUES
Barcode readers require a direct line of sight between the reader and the printed barcode but RFID readers do not. They simply need to be held in proximity to the tag.
In asset management systems this may limit where on the asset the barcode is applied. It has to be easily visible to the person checking the asset and so it may also be more likely to be removed or defaced. This can increase the costs for the user of barcode systems:
– Applying printed bar code labels to assets takes longer, labels must be positioned carefully so they are visible.
– Checking items takes longer as readers have to be positioned exactly in relation to the label.
2. READ DISTANCE ISSUES
RFID tags (especially UHF tags) can be read at much greater distances. An RFID reader can access information on tags at distances up to 10 metres. The range to read a barcode with a high level of success is much less, typically no more than a foot or so.
In RFID based systems this means that the person checking the item can do so without getting close to it, saving
time and eﬀort when checking assets.
3. DISCRIMINATION / READ SPEED
An RFID reader can read tags much faster than barcodes can be read. Read rates of many tags per second can be achieved. Barcode readers usually take a second or more to successfully complete a read.
In an asset management, for example, an RFID reader can read all the asset tags within a room with a sweep of only a few seconds whereas a bar code based system would need the user to locate each item individually. This makes the checking process faster and more reliable since items within a location cannot be overlooked (in cupboards or drawers, for example).
RFID tags can be installed in areas where there is moisture, grease or dirt without it aﬀecting the read success rates. RFID tags can also be installed inside of an asset’s casing. Barcodes can be laminated in order to improve their resistance to environmental factors but coded labels can be defaced and torn, accidentally (particularly since the label has to be on the outside of the item in an accessible area) or deliberately. Using RFID means items are not ‘lost’ due to missing or unreadable labels.
5. READ-WRITE CAPABILITY
Information cannot be written on a barcode once it has been applied. If codes need to be updated for any reason then a new label must be printed and applied with the associated risk of error. RFID tags can be updated with the tag in place.
In business applications this can make for a much more ﬂexible system design. The tag can carry the date of the last time it was inspected for example or a code can be added indicating that it should not be removed from a particular location.
6. PORTAL POSSIBILITIES
A barcode can only be read as a result of a conscious decision to access the data on the code, either by moving the item past a reader or moving the reader across the label. An RFID reader can detect a tag simply by virtue of it being in the same general area as the reader.
In RFID systems, readers can be built into doorway portals in order to detect the movement of an asset from a particular location. This can reduce theft or inadvertent loss of assets as a result of inter-department loans or relocation to home premises. It can also be used (with appropriate coding mechanisms) to allow the movement of some items (portable computers, for example) while raising an alarm at the movement of other assets (projectors, servers or monitors).