RFID+ Study Guide and Practice Exam
Packed full of special features and material to aid and reinforce learning, this comprehensive study guide provides 100% coverage of all objectives for the CompTIA RFID+ exam.
TABLE OF CONTENTS RFID+ Study Guide and Practice Exam
Chapter 2: The Physics of RFID
Overview
| Exam Objectives | What It Really Means |
|---|---|
| 8.1 Identify RF propagation/ communication techniques. | Understand modulation, inductive coupling, and backscattering. You must know that low frequency systems use inductive coupling because low frequency means high wavelength means large antenna. |
| 8.2 Describe antenna field performance/characteristics as it relates to reflective and absorptive materials (may use scenarios). | Understand the physical quantities that describe the loss of power or a change of direction in an RF wave propagating through the space, such as absorption, reflection, refraction, and scattering. You must know that water is a good absorbent of RF waves and metals are good reflectors. |
| 8.3 Given a scenario, calculate radiated power output from antenna based on antenna gains, cable type, cable length, interrogator transmit power (include formulas in scenario). | Learn how to calculate physical quantities related to the power emitted by an antenna such as antenna gain and effective radiated power (ERP). You must also know what characteristics impact the propagation of the RF signal from the source to the antenna such as cable loss and impedance. |
Introduction
The core functionality of an RFID system is the communication between a reader and a tag. The communication is carried out using RF waves, which are basically the EM waves with frequencies from the subspectrum of EM frequency spectrum called radio frequencies. The propagation of these waves is governed by the underlying physics principles. The goal of this chapter is to help you understand some physics concepts related to this communication. To accomplish this...
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