Step 3: Set Measurement Parameters

Step 3: Set Measurement Parameters

Last updated: January 16, 2009

The following information provides additional details on Step 3 of the Programming Flowchart. This information is applicable to all test applications.

Description

In this step you set up the conditions under which the measurements operate. You do this by configuring measurement parameters.

Contents

Measurement Parameters Overview

There are two different types of measurement parameters:

  • Generic Measurement Parameters
  • Measurement-Specific Measurement Parameters

The SETup subsystem is used to configure measurement parameters. Each individual measurement parameter can be set and queried using the associated SETup subsystem command. The general hierarchy of the SETup subsystem command structure is as follows:

 
SETup:<measurement mnemonic>:<measurement parameter> <parameter setting/value>

   
NOTE
Not all measurements use all measurement parameters. Refer to the GPIB syntax listing for the detailed list of measurement parameters for individual measurements.
   

Generic Measurement Parameters

There are three types of generic measurement parameters:

  • Measurement Count (used by most measurements)
    Measurement Count State
    Measurement Count Number

  • Measurement Timeout (used by all measurements)
    Measurement Timeout State
    Measurement Timeout Time

  • Measurement Trigger (used by most measurements)
    Trigger Arm (used by all measurements)
    Trigger Source (not applicable to analog measurements)
    Trigger Delay (not applicable to analog measurements)

Measurement Count Parameters

The measurement count parameters control measurement averaging. The STATe command turns averaging on or off, and the NUMBer command determines the number of averages. The SNUMber command is a complex command which allows you to turn averaging on and set the number of averages in one command.

Statistical Measurement Results Parameters
Parameter Command Syntax
Measurement Count
State		 SETup:<meas-mnemonic>:COUNt:STATe <ON|1|OFF|0>
Measurement Count
Number		 SETup:<meas-mnemonic>:COUNt:NUMBer <numeric
value>

Measurement Count
Number and State

SETup:<meas-mnemonic>:COUNt[:SNUMber] <numeric
value>
Programming Example:
 
OUTPUT Test_set;"SET:DTXP:COUN 10"

sets the multi-measurement count state to ON and set the number of averages to 10 for the digital transmit power measurement.

Measurement Timeout Parameters

Measurement timeout parameters control the maximum time that a measurement executes. TIMe sets the amount of time and STATe determines if the timeout is in use. The STIMe command is a complex command which enables you to set both parameters in one command.

Measurement Timeout Parameters
Parameters Command Syntax
Measurement
Timeout Time and
State		 SETup:<meas-mnemonic>:TIMeout[:STIMe] <numeric
value>[<suffix>]
Measurement
Timeout State		 SETup:<meas-mnemonic>:TIMeout:STATe <ON|1|OFF|0>
Measurement
Timeout Time		 SETup:<meas-mnemonic>:TIMeout:TIME <numeric
value>[<suffix>]
Programming Example:
 
OUTPUT Test_set;"SET:DTXP:TIM 10"

sets the measurement timeout state to ON and set the measurement timeout time to 10 seconds for the digital transmit power measurement.

Measurement Trigger Parameters

There are three measurement trigger parameters. They control the arming of a measurement, the source of the trigger, and the trigger's delay.

  • The trigger arm parameter determines whether the test set makes one measurement and then stops (single), or automatically re-arms upon completion of one measurement and repeats the process (continuous). The recommended setting when writing a control program is single (CONTinuous OFF).

  • The trigger source parameter selects the source of the measurement trigger signal. The recommended Trigger Source setting when writing a control program is AUTO.

   
NOTE
Trigger source is always IMMediate for analog measurements and cannot be changed by the user.
   

  • The trigger delay parameter controls the delay between the trigger event (the point in time at which the trigger signal is received) and the start of sampling. Negative values indicate that the sampling should occur prior to the trigger event.

   
NOTE
Trigger delay is not applicable to analog measurements.
   

Measurement Trigger Parameters
Parameter Command Syntax
Trigger Arm SETup:<meas-mnemonic>:CONTinuous <ON|1|OFF|0>
Trigger Source SETup:<meas-mnemonic>:TRIGger:SOURce <AUTO|IMMediate|PROTocol|RISE>
Trigger Delay SETup:<meas-mnemonic>:TRIGger:DELay <numeric value>[<suffix>]

   
NOTE
You can set the Trigger Arm for all measurements to single (CONTinuous OFF) using the following command syntax:

 
SETup[:ALL]:CONTinuous:OFF
   

Programming Example:
 
OUTPUT Test_set;"SET:CONT:OFF"

sets the trigger arm to single for all measurements.

Programming Example:
 
OUTPUT Test_set;"SET:DTXP:TRIG:SOUR AUTO"

sets the trigger source to AUTO for the digital transmit power measurement.

Programming Example:
 
OUTPUT Test_set;"SET:DTXP:TRIG:DEL 10 US"

sets the trigger delay to 10 microseconds for the digital transmit power measurement.

Measurement-Specific Measurement Parameters

Measurement-specific measurement parameters set up operating conditions for a specific measurement. For example:

  • Setting the channel power measurement speed in IS-2000
  • Setting ORFS frequency offsets in GPRS
  • Setting number of bits for the FBER measurement in GSM

Refer to the GPIB syntax listing for the detailed list of measurement parameters for individual measurements.

Programming Example:

 
OUTPUT Test_set;"SET:CPOW:MSP FAST"

sets the IS-2000 channel power measurement speed to fast.

Programming Example:

 
OUTPUT Test_set;"SET:ORFS:SWIT:FREQ 400 KHZ"

sets the first ORFS offset to 400 kHz.

Programming Example:

 
OUTPUT Test_set;"SET:FBER:COUN 10000"

sets the number of fast BER bits to test to 10,000 bits.

Program Example Setting Both Generic and Measurement-Specific Measurement Parameters

 
! Set trigger arm to single for all measurements:
!
OUTPUT Test_set;"SET:CONT:OFF"
!
! *****************************************************
! Configure Modulation Accuracy Measurement:
!
OUTPUT Test_set;"SET:MACC:COUN 5"	
! Example of using a complex command to set both the
! measurement count state and number at the same time.
!
OUTPUT Test_set;"SET:MACC:TRIG:SOUR AUTO"
! Sets trigger source to auto.
!
OUTPUT Test_set;"SET:MACC:TIM 15"        
! Sets timeout state to ON and time to 15 sec.
!
OUTPUT Test_set;"SET:MACC:EVM10:STAT ON"
! Turns the EVM10 State ON
!
! ******************************************************
! Configure Digital TX Power Measurement:
!
OUTPUT Test_set;"SET:DTXP:COUN 5"
OUTPUT Test_set;"SET:DTXP:TRIG:SOUR AUTO"
OUTPUT Test_set;"SET:DTXP:TIM 5"
!
! ******************************************************
! Configure Frequency Stability Measurement:
!
OUTPUT Test_set;"SET:FST:COUN 3"
OUTPUT Test_set;"SET:FST:TIM 10"
!
! ******************************************************
! Configure Analog TX Power Measurement:
!
OUTPUT Test_set;"SET:ATXP:COUN 5"
OUTPUT Test_set;"SET:ATXP:TRIG:SOUR AUTO"
OUTPUT Test_set;"SET:ATXP:TIM 15"