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Section 2, Microwave Path Engineering Basics

TRACER 2210/3202 System Manual

22

© 2002 ADTRAN, Inc.

61280012L1-1A

Coaxial cable will be required to attach the TRACER 3202 mast unit to the antenna.  The length of the 
cable will vary from a few feet to several feet, depending upon your application and the proximity of the 
TRACER 3202 to the antenna.  Since the data/power cable attaching the TRACER 2210 indoor unit to the 
TRACER 3202 mast unit can operate at lengths of up to 700 feet, it is recommended that this cable absorb 
as much of the length between the 2210 unit and the antenna as possible.  This will also decrease coaxial 
cable losses in the overall power budget for the link, which was described previously.

Various grades of coaxial cable will work sufficiently well for connecting the TRACER 3202 unit to the 
antenna.  A low-loss coaxial cable is suggested to minimize cable losses.  One end of the cable will require 
an N-type male connector (plug) to mate with the TRACER 3202 unit.  The other end of the coax will 
require a connector compatible with the antenna chosen for the installation, which is usually also an N-type 
male connector (plug).  Additionally, it is recommended that both connectors on the coaxial cable be 
weatherproofed from the elements to prevent corrosion and electrical shorting.

Table 3 gives typical loss figures for some of the more common coaxial cable types, per foot

In certain areas where lightning strikes are frequent, a lightning arrestor can be installed directly on the 
antenna.  This will help protect the RF electronics in the downstream path from damaging voltages and 
currents, including the TRACER 3202 unit.

Receiver sensitivity is a value expressed in decibels referenced to one milliwatt (dBm) that corresponds to 
the minimum amount of signal power needed at the receiver to achieve a given bit error rate (BER).  
Receiver sensitivity is usually a negative number of decibels, and as such smaller receiver sensitivity is 
better for a given BER.  Several factors affect receiver sensitivity, including the data bandwidth of the 
wireless link, and the amount of additional signal degradation introduced in the receiver electronics. The 
receiver sensitivity of the TRACER 3202 is -86 dBm at 10

-6

 BER.

Fade margin is a value indicating the amount of extra signal power available to the receiver to operate at a 
maximum bit error rate (BER).  Higher levels of fade margin are better, and will protect the viability of the 
microwave link against signal fading.  Fade margin is simply the difference between the available signal 
power at the receiver and the receiver sensitivity, discussed previously:

RG-213, RG-214, RG-393

0.2

RG-142

0.3

RG-58, RG-223

0.4

RG-174, RG-316

0.7

–

–

–

–

+

+

=

=

(dB)