Mean Square Error Concept; Max Power Input; Table 2: Mse Values - Trango Systems TrangoLINK APEX 18 User Manual

Why is Opmode Important?
Opmode is important since if Opmode is not configured correctly the radio will not
transmit to establish a link. There are also certain functions that can only be performed
while the radio is in Opmode "Off." The following commands can only be performed
with Opmode "Off"
• Setting / Changing Transmit Frequency
• Enabling Loopback
FACTORY DEFAULT OPMODE IS "OFF." DEFAULT OPMODE SHOULD BE CHANGED
!
BEFORE RADIOS ARE DEPLOYED. CONSOLE MANAGEMENT IS POSSIBLE
REGARDLESS OF OPMODE.

Mean Square Error Concept

Mean Square Error (MSE) is similar to Signal to Noise Ratio (SNR) except that is
accounts for distortion and interference in addition to noise power. Distortion may come
from several sources such as IF cables that are improperly constructed path
degradations such as multipath or Fresnel zone encroachment. Interference may not
only come from other transmitters on the tower, but also from high power transmitters in
the indoor shelter where the IDU is located or from transmitter located very close to the
cable. There are maximum acceptable MSE values for each modulation which are
useful in determining the quality of the link. The MSE value reported is only relevant to
one tx-rx path, so the MSE of each tx-rx path must be evaluated to verify the link is
operating cleanly. The lower the number the better so a -35dB is better than a -30dB.
The table below shows the maximum MSE value to expect in IF Loopback, Normal
Operation, and Absolute Maximum.
Maximum Expected
value IF loopback
Maximum Expected
value Normal
operation
Absolute Maximum
for 1E-6 BER

Max Power Input

TrangoLINK Apex™ 18 User Manual Rev. 1.0
MSE Expected and Maximum values
QAM256 QAM128
-36 -36
-32 -32
-28 -25

Table 2: MSE Values

Section: Chapter 2 - Getting Started
QAM64 QAM32 QAM16 QPSK
-36 -36
-32 -32
-22 -19
-36 -36
-32 -32
-16 -9
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