Motorola ASTRO 25 GTR 8000 Manual page 188

MN003286A01-E
Chapter 5: GTR 8000 Base Radio Optimization
a From the CSS menu, select Service → Test And Measurement Screen.
b Click Change to Service Mode.
c At the confirmation screen, click OK.
The base radio halts activity in the current mode and switches operation to the requested
mode.
d Re-open the Test And Measurement Screen.
4 Initiate TTA testing:
a On the Test And Measurement Screen, select the ASTRO BER RSSI Report tab.
b In the Pattern Type field, select Project 25.
c In the Sampling Period (sec) list box, enter 1 for the required seconds.
d Set the Analyzer Generate Frequency equal to the Base Radio Rx Frequency.
5 Test the Rx Noise Level with the TTA terminated:
a Turn the analyzer generator OFF.
b In CSS, click Start RSSI Measurement.
c Record the RSSI Value in the RSSI Level Terminated field of the FDMA Chan sheet.
This Rx Noise Level is a relative value and used for future comparisons.
6 Test the Rx RSSI Test Port Reference Level with the TTA terminated:
a Turn the analyzer generator ON.
b Establish an Analyzer Generate RF Level that produces an RSSI Level of -90.0 dBm.
c Record the Analyzer Generate RF Level in the Gen Level Reference field of the FDMA Chan
sheet.
The sheet calculates the Actual Reference Level.
d In CSS, click Stop RSSI Measurement.
The Actual Reference Level is a relative value used for future comparisons to assist in
troubleshooting.
• This test establishes a known reference that is about 30 dB above the typical noise floor,
which minimizes the contribution of noise to the measurement and is a better indicator of the
gain through the receive system.
• Testing at the sensitivity level is a function of the carrier to noise ratio. Noise has a much
bigger impact when testing at the sensitivity level.
• The goal of this test is to give you the information to determine if you have a gain issue or a
noise issue when troubleshooting a receive problem.
7 Test the Rx Sensitivity with the TTA terminated:
a In CSS, click Start BER Measurement.
b Adjust the Analyzer Generate RF Level for a 5% ± 0.25% BER.
c Record the Analyzer Generate RF Level in the Gen Level Terminated field of the FDMA
Chan sheet.
d In CSS, click Stop BER Measurement.
e Click Start RSSI Measurement.
f Record the RSSI (dBm) value in the RSSI Sensitivity field of the results sheet.
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