User`s guide

2-8
GPIB Tutorial and Examples
Example C - Making Measurements
Select commands from section “GPIB Commands Used in Exercises” to create the
following program flow:
❒ Select single trigger mode for DSP measurements.
❒ Establish call as in exercise A.
❒ Perform TX peak power test on channels 1, 63, 124, levels 5 to 15 with code from
exercise B and C.
❒ Display the DSP analyser phase and frequency error screen.
❒ Set up a loop to count through three TX Levels: 5, 10 and 15.
❒ Command the phone to the new TX Level.
❒ Set up a loop to count through three ARFCN: 1, 63, 124.
❒ Command the phone to the new ARFCN.
❒ Trigger a DSP measurement.
❒ Query the peak phase error and rms. phase error.
❒ Query the frequency error and TX peak power.
❒ Query the RF analyser expected input.
❒ Compare measured and expected power, loop to trigger DSP measurement if they are
more than 1dB different. Loop a maximum of three times.
❒ Print the ARFCN, TX Level, Peak and Rms. Phase Error and Frequency Error.
❒ Repeat for the next ARFCN.
❒ Repeat for the next TX Level.
❒ Return to the Cell Control screen.
❒ End call as in exercise A.
Tips:
Placing the TX Level changing loop outside the ARFCN changing loop has several
benefits. The process of changing ARFCN is faster, so the program will run more quickly.
The delay associated with the first ARFCN change will go in parallel with the time taken
for the mobile to respond to the SACCH and change TX Level. This increases the
probability of the mobile being settled on the new TX Level when the DSP measurement
is performed, reducing the number of times it will need to be repeated to get a TX peak
power value close to the expected value. Look at the ‘PERFORM DSP
MEASUREMENTS’ section of example program 1 for more help.