Radio frequency identification (RFID), is a wireless technology based on the reflection and absorption of radio waves to automatically detect, identify and track assets. The assets are tagged with RFID tags or labels which transmit the signals to and from the reader.
Active vs. Passive RFID Tags Passive RFID tags are powered by radio signals emitted from an RFID reader. The signals are sent to the chip of the tag, activating and powering the tag to send signals back to the reader along with the data contained in its chip. This process is known as backscatter. Active RFID tags contain a power source, such as a battery, within the tag for a stronger read. When using active RFID, the reader and present RFID tags continuously send signals to one another in order to collect data in real time.
Passive RFID tags are a less expensive option than active RFID and can last a lifetime. Active RFID is beneficial for receiving data from longer distances at faster rates.LF vs. HF/ NFC vs. UHF vs. Dual Frequencies
|Low Frequency (LF)||High Frequency (HF)/ Near Field Communication (NFC)||Ultra-High Frequency (UHF)||Dual Frequency|
|Frequency||125 - 134 kHz||13.56 MHz||860 - 960 MHz||13.56/860 - 960 MHz|
|Read Range||Up to 10 cm.||Up to 3 ft.||Up to 100+ ft.||Up to 100+ ft.|
|# of Tags read at once||Single||Single||Multiple||Single Multiple|
|Read near Metal or Liquid||Yes||Yes||Depending on Design||Yes|
HF/ NFC is beneficial for positive association of a tag while UHF has a further read range and reduces the time it takes to collect data by collecting multiple tags’ data at once. Dual frequency is beneficial when both NFC and UHF reads are necessary.
Handheld vs. Fixed Mount Readers Handheld readers are used to manually collect data from RFID tags. The antenna is attached to the reader itself, making it portable and easy to collect data. Rugged handheld readers are also available for applications consisting of dirt, dust, water or prone to falls.
Fixed mount readers are used to automatically collect data from RFID tags. Each reader usually contains 2 or 4 antennas placed around an area and is connected to a power source and an Ethernet cable, making them immobile. The advantage of fixed mount readers is the user can choose to mix and match between various read ranges, IP ratings (sealing protection from moisture, dirt and dust) and polarizations (direction radio waves are emitted) based on their application.
Handheld Readers are beneficial for on-the-go data collection while fixed mount readers track the movement of assets, such as inventory or stock to and from a warehouse facility, in real-time.
There are several different types of RFID tags and systems available on the market each having their own advantages and limitations. When researching where to start with implementing RFID - passive RFID is comparatively less expensive, dual frequency has the capabilities of both NFC and UHF, read-write RFID chips allow for additional information to be added about each asset and handheld readers are easily portable for any application. However, diverse applications call for different RFID tags and systems, our experts are here to help find the best solution for you.