Agilent Technologies 8922M, S GSM manual Advanced Features

Making Measurements

Advanced Features

9The RF Generator may become uncalibrated in a hopping situation when the last CW frequency setting was outside the GSM or DCS band. If you are using the RF Generator outside the normal GSM or DCS bands, make sure you set a valid GSM or DCS frequency in the CW frequency before entering a hopping mode. This includes the ACTIVE CELL (ACTIVATED state on the CELL CONFIG 2 screen) on the Agilent 8922M/S.

10When using RF Rise triggering it is recommended to set MS_Parms:Timing Advance to MANUAL with the Timing Advance set to zero. If AUTO timing advance is used with RF Rise triggering, the Agilent 8922M/S, operating as a base station, will progressively command the mobile to advance timing until it is at the maximum value of 64. It is difficult to recover from this state without ending the call with the mobile. Changing back to EXT_DEMOD triggering will cause the call to drop. This is because the Agilent 8922M/S is listening for the mobile 64 bits later than the RF Rise triggering left it.

11When making measurements over the GPIB, it is often necessary to place time- out constraints in software to account for mobile failure. When a time-out is encountered while a measurement is armed but not complete, it is necessary to perform a “CLEAR” operation on the GPIB. A “RESET” operation is insufficient.

Example

ASSIGN @gpib TO 714

OUTPUT @gpib;”TRIGger:ASTate ’ARM’” ON TIMEOUT 7,5 GOTO Flag1

OUTPUT @gpib;”MEASure:DSP:PHASe:FREQuency?” ENTER @gpib;The_answer

PRINT ‘FREQUENCY:’; The_answer

OFF TIMEOUT 7 GOTO Flag2 Flag1:OFF TIMEOUT 7

CLEAR @gpib

PRINT “Timeout Occurred”

OUTPUT @gpib;”TRIGger:ASTate ‘DISARM’” Flag2:END

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