Page 62 - DCAP311_DCAP607_WIRELESS_NETWORKS

Wireless Networks

Notes – and we have achieved that goal,” he states. “Avery Dennison RFID’s technical support
team was extremely helpful in guiding our choice of RFID inlays, antennas and tags to be
sure they would perform and hold up well over time, even in the toughest environmental
conditions.”
Questions:
1. Study and analyse the case.
2. Write down the case facts.
3. What do you infer from it?
Source: http://www.starkrfid.com/about/rfid-case-studies/stark-rfid-brick-case-study.php

3.6 Summary

Radio frequency (RF) is a rate of oscillation in the range of about 3 kHz to 300 GHz, which
corresponds to the frequency of radio waves, and the alternating currents which carry radio
signals.

Electric currents that oscillate at radio frequencies have special properties not shared by direct
current or alternating current of lower frequencies.
Fiber-optic communication is a method of transmitting information from one place to another by
sending pulses of light through an optical fiber.
Fiber optics is a medium for carrying information from one point to another in the form of light.
Unlike the copper form of transmission, fiber optics is not electrical in nature.
All RF waves have characteristics that vary to define the wave. Some of these properties can be
modified to modulate information onto the wave. These properties are wavelength, frequency,
amplitude, and phase.
Wireless networks that utilize light signals, however, are not as common as these that use radio
signals.
Light signals have been in use with communications systems for even longer than RF systems.

3.7 Keywords

Radio frequency (RF): is a rate of oscillation in the range of about 3 kHz to 300 GHz, which
corresponds to the frequency of radio waves, and the alternating currents which carry radio
signals.

TRX900: is an encrypted digital wireless transmitter with optional internal backup recording
and IFB.
Frequency: refers to the number of wave cycles that occur in a given window of time.

Multipath: is the propagation phenomenon that results in radio signals reaching the receiving
antenna by two or more paths.
Modulation: is the process of varying one or more properties of a periodic waveform, called the
carrier signal, with a modulating signal which typically contains information to be transmitted.
Line Coding: is to transfer a digital bit stream over a baseband channel, typically a non-filtered
copper wire such as a serial bus or a wired local area network.
Frequency-shift keying (FSK): is a frequency modulation scheme in which digital information is
transmitted through discrete frequency changes of a carrier wave.

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