APPENDIX C. RADIO SIGNAL
PROPAGATION
Introduction
This section explains and simplifies many of the terms relating to antennas and RF (Radio Frequency) used when dealing with an RF installation system.
The following diagram depicts a typical radio system:
Figure 27: A Typical Radio System
A radio system transmits information to the transmitter. The information is transmitted through an antenna that converts the RF signal into an electromagnetic wave. The transmission medium for electromagnetic wave propagation is free space.
The electromagnetic wave is intercepted by the receiving antenna, which converts it back to an RF signal. Ideally, this RF signal is the same as that originally generated by the transmitter. The original information is then demodulated back to its original form.
RF Terms and Definitions
dB
The dB convention is an abbreviation for decibels. It shows the relationship between two values.
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