DRU digital tests
11-49
Wireless Solutions
DualMode 800 Enclosure
Maintenance Manual
MTX08
TDMA modulation accuracy test
The TDMA modulation accuracy test measures the
π
/4 DQPSK modulation
of the signals received from the TRU. To perform this test, you must use a test
equipment that can measure TDMA modulation accuracy, such as the
IFR1600 with TDMA software.
Note: The IFR1600 is used as a reference in this testing procedure. If you
are using another model of test equipment, refer to the user manual of that
equipment for the appropriate test setup and display.
Step
Action
Observation
1
Connect a VT100 (or equivalent) terminal to
the RS-232 port on the front panel of the
TRU under test.
2
By pressing the “Break” key on the terminal
keyboard, you can access the command line
mode.
The terminal will display (the TRU2 display is
shown as an example):
TRU Terminal Interface
(C) Copyright 1990,1991 Bell
Northern Research, Inc.
>
3
At the prompt (>), type:
>set lt off
4
Type:
>set pa off
The TRU transmitter is turned off.
This step ensures that the TRU is not
radiating RF power when disconnecting the
RF cable.
5
Connect the TRU under test through the
sniffer port of the duplexer to the input
connector of the test equipment (the T/R port
on the IFR1600).
6
Select the Modulation Accuracy function on
the test equipment.
For the IFR1600:
(i) select the ‘RCVR’ function with the IFR
MODE key
(ii) press the ‘F5’ key that is labeled ‘Sp Tst’
(iii) select ‘MODULATION ACCURACY’ by
pressing the ‘4’ key from the Data Entry
Keys.
The Modulation Accuracy display screen on
the IFR1600 shows:
MODULATION ACCURACY
CHANNEL 1
I/Q OFFSET=
FREQUENCY ERROR=
RMS PHASE ERROR=
RMS MAGNITUDE ERROR=
RMS ERROR VECTOR MAGNITUDE=
- continued -
Summary of Contents for DualMode 800
Page 2: ......
Page 4: ......
Page 6: ...vi Publication history Nortel Networks Confidential 411 2051 500 Draft 00 01 November 1999...
Page 82: ...2 20 Periodic maintenance 411 2051 500 Draft 00 01 November 1999...
Page 90: ...3 8 Test equipment and precautions 411 2051 500 Draft 00 01 November 1999...
Page 100: ...5 6 Master Oscillator tests 411 2051 500 Draft 00 01 November 1999...
Page 106: ...6 6 Antenna and transmission line tests 411 2051 500 Draft 00 01 November 1999...
Page 116: ...8 4 Alarm Control Unit ACU tests 411 2051 500 Draft 00 01 November 1999...
Page 138: ...10 2 ICRM tests 411 2051 500 Draft 00 01 November 1999...
Page 200: ...12 10 Enclosure maintenance 411 2051 500 Draft 00 01 November 1999...
Page 208: ...A 8 Appendix A Frequency table 411 2051 500 Draft 00 01 November 1999...
Page 215: ......