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TRACER 2210/3202 System Manual

Section 2, Microwave Path Engineering Basics

61280012L1-1A

© 2002 ADTRAN, Inc.

19

When using decibel notation, the received power equation becomes

or

Where, in the second equation the path loss has been lumped into a single quantity, L

, as discussed 

previously.  When using decibel notation, it is necessary that all quantities are individually converted to 
decibels prior to performing addition and subtraction.

When d is expressed in miles and f in GHz, the path loss expression in decibels becomes

Figure 1 illustrates a wireless link containing all of the parameters previously discussed.

With line-of-sight microwave communications, optimum system performance requires that the 
transmitting and receiving antennas are properly aligned.  This will ensure maximum received signal 
power at each receiver.  Antenna alignment must be achieved in both azimuth (along a horizontal plane) 
and elevation (along a vertical plane).  A received signal strength indicator (RSSI) is used to aid the 
equipment installer in determining when alignment is maximized, by simply ensuring maximum RSSI. 
The RSSI indicator for the TRACER 2210/3202 system is provided on the LCD display of the 2210 unit, 
and is presented as a series of asterisks.  More asterisks means more RSSI, which ensures more received 
signal strength and better link performance.

–

10

–

+

+

4

π

------------









2

=

=

(dB)

–

–

+

+

=

(dB)

96.6 20 log

10

( )

+

10

( )

⋅

+

=

(dB)

 

λ