Programming a Modulation Accuracy Measurement

Programming a Modulation Accuracy Measurement

Last updated: December 3, 2008

This section is only applicable to EGPRS.

The following procedure assumes that the mobile station is connected to the test set's RF IN/OUT connector.

  1. Change the serving cell to EGPRS. To do this via GPIB, you must first turn the cell off. See the following procedure.
    1. Turn the cell off using the CALL:OPER:MODE OFF command.
    2. Change the serving cell to EGPRS using the CALL:BCH:SCEL EGPRS command.
    3. Turn the cell back on using the CALL:OPER:MODE CALL command.
  2. Set the connection type to ETSI A using the CALL:FUNC:CONN:TYPE A command.
  3. Set the modulation and coding scheme to one which uses 8PSK modulation.
  4. Set up the modulation accuracy measurement parameters using the SETup:EMACcuracy parameters (See SETup:EMACcuracy for more information.)
  5. Turn on the mobile station and allow it to attach.
  6. Start the data connection.
  7. Use a hanging query to determine when the connection has started and to provide synchronization between your program and the test set.
  8. Initiate the modulation accuracy measurement.
  9. Fetch the measurement results using a FETCh:EMACcuracy? query. (See FETCh:EMACcuracy for more information.)

Programming Example: 

 
10    ! Turn the cell off to access the serving cell parameter
20    OUTPUT 714;"CALL:OPER:MODE OFF"
30    ! Change the serving cell to EGPRS
40    OUTPUT 714;"CALL:BCH:SCEL EGPRS"
50    ! Turn the cell back on
60    OUTPUT 714;"CALL:OPER:MODE CALL"
70    ! Set the connection type to ETSI Type A
80    OUTPUT 714;"CALL:FUNC:CONN:TYPE A"
90    ! Select a Modulation and Coding Scheme using 8PSK
100   OUTPUT 714;"CALL:PDTCH:MCSC MCS9,MCS9"
110   OUTPUT 714;"SET:EMAC:CONT OFF"!Set trigger mode to single
120   OUTPUT 714;"SET:EMAC:COUN 5"! Turn statisical results on
130   ! Turn measurement timeout on and set to 5 seconds
140   OUTPUT 714;"SET:EMAC:TIM 5"
150   !
160   !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
170   ! Turn on the mobile station and allow it to attach
180   !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
190   !
200   ! Start the data connection
210   OUTPUT 714;"CALL:FUNC:DATA:START"
220   ! Hanging query to determine when the data connection
230   !  has been established.
240   OUTPUT 714;"CALL:TRAN?"
250   ENTER 714;Tran_state
260   IF NOT Tran_state THEN
270     PRINT "DATA CONNECTION FAILED"
280     STOP
290   END IF
300   OUTPUT 714;"INIT:EMAC" ! Initiate measurement
310   ! The query below fetches the measurement results required
320   !  by the conformance specification for modulation accuracy.
330   OUTPUT 714;"FETC:EMAC:ETSI?"! Fetch measurement results
340   ENTER 714;Integrity,Rms_evm,Peak_evm,Percentile,Ferr,Origin_offset
350   END

Returned Values

The measurements returned by the FETCh? query in the programming example above are:

Related Topics

Modulation Accuracy Measurement Description

How do I make Modulation Accuracy Measurements?

Modulation Accuracy Troubleshooting

SETup:EMACcuracy

FETCh:EMACcuracy