Programming a Phase and Frequency Error Measurement

Programming a Phase and Frequency Error Measurement

Last updated: December 3, 2008

This section contains two programming examples:

Programming a Phase and Frequency Error Measurement for GSM

This section provides an example of how to make the phase and frequency error (PFER) measurement via GPIB.

The following procedure assumes that an active link is established between the test set and the mobile station. See Establishing an Active GSM Link with the Mobile Station .

  1. Configure PFER measurement parameters using the SETup subsystem.
  2. Start the PFER measurement using the INITiate subsystem.
  3. Use the FETCh? command to obtain PFER measurement results.

Programming Example

 
10  OUTPUT 714;"SETUP:PFERROR:CONTINUOUS OFF" !Configures a PFER measurement to
20                                            !single trigger mode.
30  OUTPUT 714;"SETUP:PFERROR:COUNT:NUMBER 100" !Configures a multi-measurement
40                                             !of 100.
50  OUTPUT 714;"SETUP:PFERROR:TRIGGER:SOURCE AUTO"!Configure trigger source
60                                                !to auto.
70  OUTPUT 714;"SETUP:PFERROR:SYNC MIDAMBLE" !Configures a PFER measurement so
80                                           !that burst synchronization, which
90                                           !will synchronize the timing of the
100                                          !measurement algorithm relative to
110                                          !the data sample, will be set
120                                          !to midamble.
130 OUTPUT 714;"INITIATE:PFERROR" !Starts the PFER measurement.
140 OUTPUT 714;"FETCH:PFERROR:ALL?"
150 ENTER 714;Integrity, Max_phase_err, Max_peak_error, Worst_freq_err
160 END

Returned values

The measurements returned by this program are:

  • Integrity returns the measurement Integrity Indicator (0 means a successful measurement with no errors).
  • Max_phase_err returns the maximum rms phase error in degrees

  • Max_peak_phase_error returns the maximum peak phase error in degrees
  • Worst_freq_err returns the frequency, in Hz, that is the furthest from zero, if the most positive and the most negative frequency error are the same value, the most positive will be returned.

Related Topics


Phase and Frequency Error Measurement Description

SETup:PFERror

INITiate

FETCh:PFERror

GSM/GPRS Control Program Example


Programming a Phase and Frequency Error Measurement for GPRS and EGPRS

This section provides an example of how to make the phase and frequency error (PFER) measurement via GPIB.

When using the PFER measurement with an EGPRS mobile, you can select a modulation coding scheme which uses either GMSK or 8PSK modulation. For more details on setting the modulation coding scheme, see


   
CALL:(PDTCH|PDTChannel):MCSCheme .

The following procedure assumes that a GPRS data connection has been established between the test set and the mobile station (connection status is Transferring). See Step 4: Make a Connection .

  1. Set the multislot configuration to two downlinks, two uplinks (D2U2) and set the uplink power control level for each of the two bursts using the CALL subsystem.
  2. Configure PFER measurement parameters using the SETup subsystem.
  3. Use the CALL:(PDTCH|PDTChannel):MSLot:MEASurement:BURSt command to select burst 1 for the first PFER measurement.
  4. Start the PFER measurement using the INITiate subsystem.
  5. Use the FETCh? command to obtain PFER measurement results.
  6. Use the CALL:(PDTCH|PDTChannel):MSLot:MEASurement:BURSt command to select burst 2 for the second PFER measurement.
  7. Repeat steps 4 to 6 above to perform a PFER measurement on burst 2 of the multislot configuration.

Programming Example

 
10  OUTPUT 714;"CALL:PDTCH:MSLOT:CONFIG D2U2" ! Configures the multi-
20                                            ! slot configuration to be
30                                            ! 2 downlink, 2 uplink.
40  OUTPUT 714;"CALL:PDTCH:MS:TXLEVEL:BURST 9" ! Sets the uplink power for
50                                             ! burst 1 to 25 dBm.
60  OUTPUT 714;"CALL:PDTCH:MS:TXLEVEL:BURST2 6" ! Sets the uplink power for
70                                              ! burst 2 to 31 dBm.
80  OUTPUT 714;"SETUP:PFERROR:CONTINUOUS OFF" !Configures a PFER measurement to
90                                            !single trigger mode.
100 OUTPUT 714;"SETUP:PFERROR:COUNT:NUMBER 100" !Configures a multi-measurement
110                                             !of 100.
120 OUTPUT 714;"SETUP:PFERROR:TRIGGER:SOURCE AUTO" !Configure trigger source
130                                                !to auto.
140 OUTPUT 714;"SETUP:PFERROR:SYNC MIDAMBLE" !Configures a PFER measurement so
150                                          !that burst synchronization, which
160                                          !will synchronize the timing of the
170                                          !measurement algorithm relative to
180                                          !the data sample, will be set
190                                          !to midamble.
200 OUTPUT 714;"CALL:PDTCH:MSLOT:MEASUREMENT:BURST 1" ! Perform first PFER
210                                                   ! measurement on burst 1.
220 OUTPUT 714;"INITIATE:PFERROR" !Starts the first PFER measurement.
230 OUTPUT 714;"FETCH:PFERROR:ALL?"
240 ENTER 714;Integrity1,Max_phase_err1,Max_peak_err1,Worst_freq_err1
250 OUTPUT 714;"CALL:PDTCH:MSLOT:MEASUREMENT:BURST 2" ! Perform next PFER
260                                                   ! measurement on burst 2.
270 OUTPUT 714;"INITIATE:PFERROR" !Starts the next PFER measurement.
280 REPEAT
290    OUTPUT 714;"INITIATE:DONE?"
300    ENTER 714;Meas_complete$
310 UNTIL Meas_complete$="PFER"
320 OUTPUT 714;"FETCH:PFERROR:ALL?"
330 ENTER 714;Integrity2,Max_phase_err2,Max_peak_err2,Worst_freq_err2
340 END

Returned values

This program instructs the test set to make two sets of PFER measurements, the first on burst 1 in the multislot configuration and the second on burst 2. The results returned by this program are:

Related Topics


Phase and Frequency Error Measurement Description

SETup:PFERror

INITiate

FETCh:PFERror

GSM/GPRS Control Program Example

Confidence Levels