Differentiation Features of RFID Systems - RFID: Fundamentals and Applications in Contactless Smart Cards and Identification - page 23

Smart card OS,
cryptographic
coprocessor

ISO 14443
dual interface
smart card

Smart card
OS

ISO 14443
contactless
smart card
13.56 MHz

Authentication,
encryption
(state machine)

Passive transponder
135 kHz, 13.56 MHz,
868/915 MHz, 2.45 GHz
ISO 15693, ISO 18000
ISO 14223

Anticollision

Active
transponder
868/915 MHz
2.45 GHz
ISO 18000

Read-write

EAS

Fixed code
transponder

Read-only

1 4 16 64 512 2 k 8 k 32 k 128 k

Memory size (bytes)

Figure 2.17 RFID systems can be classified into low-end and high-end systems according to
their functionality

broadcast its own serial number. It is not possible for the reader to address a read-
only transponder — there is a unidirectional flow of data from the transponder to the
reader. In practical operation of a read-only system, it is also necessary to ensure that
there is only ever one transponder in the reader's interrogation zone, otherwise the two
or more transponders simultaneously transmitting would lead to a data collision. The
reader would no longer be able to detect the transponder. Despite this limitation, read-
only transponders are excellently suited for many applications in which it is sufficient
for one unique number to be read. Because of the simple function of a read-only
transponder, the chip area can be minimised, thus achieving low power consumption
and a low manufacturing cost.
Read-only systems are operated at all frequencies available to RFID systems. The
achievable ranges are generally very high thanks to the low power consumption of
the microchip.
Read-only systems are used where only a small amount of data is required or where
they can replace the functionality of barcode systems, for example in the control of
product flows, in the identification of pallets, containers and gas bottles (ISO 18000),
but also in the identification of animals (ISO 11785).

2.4.2 Mid-range systems

The mid-range is occupied by a variety of systems with writable data memory, which
means that this sector has by far the greatest diversity of types. Memory sizes range