Step 1: Set Up the Test Set

Step 1: Set Up the Test Set

Last updated: January 16, 2009

The following information provides additional details on Step 1 of the Programming Flowchart. This information is applicable to all test applications.

Description

In this step you initialize the test set and set up the general operating conditions.

Contents

Initialize the Test Set

  • Fully Preset the Test Set

    It is important to get the test set to a known state before each production session.

    Sending the *RST command fully presets the test set, which ends all call processing and measurement processes and restores all values to defaults.

  • Clear the Error Queue

    Before each production session, it is useful to clear the error queue of any old messages. That way, you know that any messages logged are relevant to the current production session.

    Sending the *CLS command clears the error queue.

Set Up General Operating Conditions

  • Turn Debugger On

    While developing your code, it is very useful to enable the GPIB debugger using the
    SYST:COMM:GPIB:DEB ON command. When the debugger is on, the test set alerts you when you send an incorrect command, and it also tells you which symbol or letter in the command is incorrect.

   
NOTE
You should turn the debugger off once you have finished development and your code is stable.
   

  • Set Operating Mode

    The test set contains a base station emulator (BSE), whose primary purpose is to provide enough call processing to allow parametric measurements of a mobile station's RF signal.

    An important characteristic of the test set's base station emulator is its operating mode. The operating mode sets the way in which the base station emulator interacts with the mobile station.

    Active cell mode is used when emulating a normal cell. Active cell mode allows active signaling between the mobile station and BSE. The mobile station camps to the BSE signal, and an actual call is established.

    In test mode, the mobile station synchronizes to the BSE signal and transmits an appropriate signal which the test set analyzes.

    The test set's operating mode is set using the following command:

    Command to Set the Test Set's Operating Mode

    Command

    		 Example

    CALL:OPER:MODE <operating mode>

    CALL:OPER:MODE CELL

  • Set Amplitude Offsets

    To achieve accurate measurement results, it is important to account for losses in the cabling and fixturing between the mobile station and test set. You must determine what the losses are for your test setup and then specify the appropriate frequency-dependent amplitude offset values.

    You can specify amplitude offsets for up to 20 frequencies using the following commands:

    Commands to Set Amplitude Offsets

    Command

    		 Example

    SYST:CORR:FREQ <freq1>, <freq2>, <freq3>

    SYST:CORR:FREQ 800MHz, 1800MHz,
    1900MHz

    SYST:CORR[:SGAin] <offset1>,
    <offset2>, <offset3>

    		 SYST:CORR -0.7, -1.0, -1.2

  • Set Display Mode

    To achieve a slightly faster test execution speed, you can disable the front panel display on the test set using the DISP:MODE FAST command.