User's Guide

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7 Introduction to the RIFD System
7.1 RFID System
An RFID system is comprised of the control computer of the reader, antennas, antenna connection cables and the tags.
The figure 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 field 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 randomly,
with equal distribution across the 52 available channels. Each channel is used for max. 400ms in an interval
of 20s.
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 specific applications, 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-specific control software can run directly on the
reader. Therefore, a stand-alone operation without permanent network connection is possible.