LF 125KHz
Pet tagging
Access Control
PROS
Low price against medium read range with minimal environment interference. Can be used in just about every country in the world.
CONS
Very low security and data storage together with slow baud rate reduces the ability to acheive multi-card reading in an open area.
HF 13.56MHz
Access Control
Asset Tracking
Payment Cards (including Bank Cards)
Security Bands
PROS
Fairly low price but with very high security and data storage facility. Cards are near field reading only but a fairly high baud rate ensures quick reading of the encrypted data. Due to the close read range, interference is almost non-existing. This frequency is also the most widely used which means that more hardware is available and can be used in just about every country in the world.
CONS
Close read range only means hands free is not available and neither is multi-card reading.
UHF 860-960MHz
Asset Tracking
Security Bands
PROS
A higher passive read range allows for total hands free, plus the high baud rate ensures that multi-card reading is also possible. With the use of active cards, this read range is greatly improved. The antenna size is relatively small and the frequency is rapidly becoming very common so available hardware is becoming more readily available.
CONS
The hardware is expensive and also the most susceptible to environment interference due to the higher frequency especially where metal or liquids are involved. The frequencies used in this product can vary between geographical locations, with some regions enforcing licensing requirements for certain frequencies. This non-standardisation of frequencies can cause compatibility issues especially with vessels that work around the world.
SUMMARY
The most secure and multi-appliance card is the HF 13.56MHz range but this is limited to near field only. UHF 860-960MHz is the best choice for long range multi-card reading but is susceptible to interference and has world-wide compatibility problems. The LF 125KHz has the least interference issues but has the least security and problems with multi-card reading.
In summary, for short range the 13.56MHz is best and long range the UHF 860-960MHz is best (although antenna positioning should be carefully considered). A hybrid system using both HF & UHF would be the best all-round performing and would allow for near field reading with high security for access control and hands free monitoring of tags with multi-read at choke points and gateways.