Nortel DualMode 800, Maintenance Manual

Page: 189 / 216

DRU digital tests 11-51
Wireless Solutions DualMode 800 Enclosure Maintenance Manual MTX08
14 Start the test by pressing the F1 function key
labeled “RUN” on the IFR1600. (For the
operation of other types of test equipment,
refer to their user manuals.)
The following will be measured in this test:
I/Q Offset—20 x Log of the I/Q offset
magnitude indicates the amount of carrier
feed through.
Frequency Error—Difference between the
received carrier frequency and the ideal
carrier frequency.
RMS Phase Error—RMS value of the
absolute phase errors.
RMS Magnitude Error—RMS value of the
difference between the ideal magnitude and
the received magnitude.
RMS Error Vector Magnitude—RMS value of
the magnitude of the error vectors.
Test results will be displayed as follows:
MODULATION ACCURACY
I/Q OFFSET= (less than -30 dBc)
FREQUENCY ERROR= (+220 to -220
Hz)
RMS PHASE ERROR= (N/A)
RMS MAGNITUDE ERROR= (N/A)
RMS ERROR VECTOR MAGNITUDE= (less
than 12.5%)
15 Repeat Step 14 ten times and take the
average over the ten readings.
16 Once the test is completed, a
π
/4 DQPSK I/Q
plot can be performed by pressing the “F2”
function key on the IFR1600.
Note
: For more information on plotting
results, see the IFR1600 dual mode cellular
system analyzer manual. (For the operation
of other types of test equipment, refer to their
user manuals.)
17 Type:
>set pa off
Status change was successful.
The TRU transmitter is turned off.
18 Disconnect the test equipment from the
sniffer port of the duplexer.
19 Type:
>execute reset
This command removes the run inject
command and resets the TRU.
20 Disconnect the terminal interface from the
TRU.
- End -
Step Action Observation