User's Guide
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8 Introduction to the RIFD System
8.1 RFID System
An RFID system is comprised of the control computer of the reader, antennas, antenna connection cables and the tags.
The gure below shows the schematic structure of the system:
Ethernet
or
serial interface
RFID UHF
Gen2 Tag
Fig. 1: RFID system (example)
The tags consist of an antenna and a small chip. The chip is the true carrier of the information, the EPC (
Electronic
Product Code
) number. This number can identify products or product groups. Alternatively, the EPC can be overwritten
with new information.
To read the tag information, the reader switches on an RF carrier by means of a selected antenna, thus supplying the
tags in the RF eld with energy.
To read the information from a tag, it is necessary to inventory the tags and then select a tag from the population of
tags. Upon successful completion of the inventory, the EPC number of each tag can be read and sent to the PC. It is
possible to attach additional information to the EPC, for example, the antenna which read it or the time at which it was
read.
NOTICE
The reader operates using the frequency hopping process to avoid faults and interference between readers.
Within the FCC area, this procedure is mandatory. The reader changes its transmission frequency ran-
domly, with equal distribution across the 52 available channels. Each channel is used for max. 400ms in an
interval of 20s.
The
ReaderStart v3
software can be used for testing and parametrising.
The communication between the
ReaderStart v3
and the reader is based on the DLL (
Dynamic Link Library
), which
includes the communication protocol, see
Communication Protocol Kathrein RFID UHF Readers
. For specic applica-
tions, the user can build its own control software based on the reader DLL. The DLL includes all the relevant commands
and functions required to control the reader.
It is necessary for the user to create his own control software. The user-specic control software can run directly on the
reader. Therefore, a stand-alone operation without permanent network connection is possible.