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MODELING ELECTROMAGNETIC WAVE
PROPAGATION IN PAPER REEL FOR UHF
RFID SYSTEM DEVELOPMENT

M. M. Keskilammi, L. T. Sydanheimo and M. A. Kivikoski
Tampere University of Technology, Institute of Electronics,
Rauma Research Unit, Kalliokatu 2, FI-26100 Rauma, FINLAND

ABSTRACT

In passive radio frequency identification systems (RFID), data and power is transferred between a
reader and an identification device wirelessly by means of electromagnetic waves, Finkenzeller (2003).
Antenna solutions, in both the identification device and the reader, are crucial to the performance of
radio frequency identification systems. To improve the performance of these RFID systems application
specific antennas can be used for challenging items including metals, liquids or lossy material. This
paper describes the simulation model for radio wave attenuation in paper reel. Simulated values for
propagation in different grades of paper are presented. Theoretical background is also discussed.

KEYWORDS

RFID, Antennas, Automation, Communication Systems, Sensors

INTRODUCTION
According to their operation frequency, radio frequency identification systems are dividable into low
frequency and high frequency systems. In low frequency systems, a magnetic field is used in the
coupling between the identification device and the reader, and various loop solutions are used as
antennas. In low frequency systems, the reading distance is short and the reading distance depends on
the areas of the antenna coils and their mutual positions. In high frequency systems, an electric field is
used in the coupling, and the antennas used are usually dipole, folded dipole or microstrip antennas.
Out of these, dipole and folded dipole antennas are omnidirectional, whereas a microstrip antenna is
directional. In high frequency systems, the identification device is either active or passive. Active
identification devices comprise a radio transmitter and a battery, whereas passive systems use the
energy obtained from the reader. In high frequency systems, the reading distance is longer than in low
frequency systems. This paper concentrates on passive high frequency RFID systems operating in ultra
high frequency (UHF) band.