03 Loop Antennas 05 RFIDSystems（05 RFIDSystems 03环形天线）.pdf

03 Loop Antennas 03 Loop Antennas 3rd unit in course 3, RF Basics and Components 3rd unit in course 3, RF Basics and Components Dipl.-Ing. Dr. Michael Gebhart, MSc RFID Qualification Network, University of Applied Sciences, Campus 2 WS 2013/14, September 30th Content Content What is a loop antenna? Production technologies - Etched antenna - Embedded wire antenna - Electroplated antenna - Printed antenna - Assembly Antenna design for Readers and Cards - Inductance, resistance, capacitance Antenna equivalent circuit element value measurement Ferrite foils Tolerances - Production tolerance, temperature dependency page 2 What is a loop antenna? What is a loop antenna? The loop antenna is a distributed component with inductance (L) as main element and capacitance (C) and resistance (R) as parasitic network elements. End of coil turns For simulation it must be represented by an equivalent Start of coil turns equivalent circuit network of lumped circuit lumped elements. Over a wide frequency elements L1 Ln range this can be a loose coupled C0 L0 R0 C1 Cn reactive ladder network of resonance circuits - it has se