RFID Tags: Passive, Active And Hybrid
Monday, September 6th, 2010All RFID tags are used to store and ultimately send data. They can best be thought of as the replacement for the bar code. However, they have significant advantages over bar codes. For instance: RFID tags can hold much more data than bar codes; they can be scanned from further away and they can in point of fact send data, not only store data.
There are three kinds of RFID tags: passive, active and hybrid. Passive RFID tags are the least expensive, because they are less complex. They have to be induced to disclose their data by borrowing power from an RFID reader. When the reader’s radio waves hit them, they echo back their data. This is the sort of tag used in clothing in a retail outlet or on crates in a warehouse.
On the other hand, active RFID tags have a battery, a transmitter and an antenna so that they are always transmitting. These units are obviously a lot more expensive and so are used only on more expensive items such as a container, a battle tank, an aircraft, on criminals ankle bands or on an animal of an endangered species.
The hybrid RFID tag is capable of sending, but it needs to be told to transmit; it has to be turned on by a signal. This signal could be a satellite flying over head. These hybrid RFID tags are also expensive, but the battery lasts longer because they are not ‘always on’. These tags have the same applications as the active tags, but are suitable for use where it is not critical to know where something is every minute of the day: for instance cattle in a field or sheep on a mountain.
Passive tags can be attached permanently by sewing them into linings or putting them under skin because they do not have their own power source and do not wear out. This is a cause of anxiety to some people who worry about an invasion of their privacy or the erosion of their human rights.
Active and hybrid tags are most frequently plainly visible so that the batteries can be changed as and when required. If this is going to be unlikely to take place, as in the case of wild animals, the tag can have a biodegradable clasp which will break sometime after the probable expiry of the battery.
Some uses for RFID tags are on season tickets so that the holder can pass through the style more quickly than a customer paying by cash. It has uses in security; most of the ID badges you see pinned to jackets have RFID built into them so that security guards do not have to stop and question everybody.
They can be put into trucks that regularly cross borders so that they do not need to stop for identification. They can be placed in windscreens so that as you pass through a motorway toll station, either your credit card is billed or the charge is added to your company’s monthly statement.
Hospitals utilize them on patients so that they do not lose anyone or misidentify them. RFID tags are helpful in our daily lives but people are concerned about criminals being able to read all this information too readily as well.
Owen Jones, the writer of this article writes on several topics, but is currently involved with the RFID asset tracking. If you would like to know more, please go to our website at Active RFID Management.
