Receiver Power - ADTRAN TRACER 6000 SERIES User Manual

TRACER 6000 Series Split System Manual
where the variables in the equations are defined as
P received power (dBm)
R
P receiver sensitivity (dBm)
sens
P transmitted power (adjustable up to 20 dBm maximum)
T
G transmit antenna gain (decibels referenced to an isotropic source – dBi)
T
G receive antenna gain (dBi)
R
L other losses (RF coaxial cable, etc. – dB)
L path loss (dB)
P
Higher levels of fade margin indicate stronger protection against signal fading and a more reliable link. For
most applications, 20 to 30 dB of fade margin should ensure a reliable link.
The following sections further discuss the necessary power calculations and their components.
4.

RECEIVER POWER

The viability of a particular microwave path is determined by the power of the transmitted microwave
signal, the transmit and receive antenna gain, distance, and accumulated system losses (such as RF coaxial
cable losses and path loss).
The equation relating received signal power to the other microwave parameters is
or (in decibel notation)
where the variables in the equations are defined as
P received power (dBm)
R
P transmitted power (adjustable up to 20 dBm maximum)
T
G transmit antenna gain (decibels referenced to an isotropic source – dBi)
T
G receive antenna gain (dBi)
R
λ
carrier wavelength (meters)
d path distance (meters)
L other losses (RF coaxial cable, etc. – dB)
L path loss (dB)
P
When using decibel notation, all quantities must be individually converted to decibels
prior to performing addition and subtraction.
612806320L1-1B
2
λ
P T G T G R
P R = ------------------------------
π
( ) 2 d 2 L
4
P = P + G + G - L - L
R T T R
Copyright © 2005 ADTRAN, Inc.
Section 2 Microwave Path Engineering Basics
(Watts, W)
(decibels referenced to a milliwatt, dBm)
P
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