Transmitter CW Power and Frequency Offest Test (CW)

Introduction

For WLAN Device Under Test (DUT) Continuous Wave (CW) signal transmission there are two measurements available:

These can be used for Transmitter Power or Transmitter Frequency verification. These measurements can also be used as part of a calibration routine for the Wireless LAN DUT. Linear or Binary routines can be used.

The Average Power measurement can be used on a CW or bursted modulated signal; for a modulated Center Frequency Accuracy measurement the Frequency Error measurement is used.

 

Table 1: Power / Frequency measurement differences with CW and Modulated

 

Continuous Wave (CW)

Bursted Modulated

Power Measurement

 Average Power

 Average Power

Frequency Measurement

CW Frequency Offset

Frequency Error

 

N4010A WLAN Virtual Front Panel

Programmatically Setting Up the N4010

Ensure the N4010 WLAN Test DLL (COM or .NET version) has been set up as shown in Step 1 - Reference the N4010 WLAN COM Dynamic Link Library (COM DLL) and Step 2 - Create the Instrument Object that is, reference and create a connection with the N4010 instrument via the VISA resource address. There is no need to redo steps 1 & 2 unless the instrument is power cycled.

The measurement setup can be common to several measurements. N4010 setup conditions only need to be changed when the WLAN device parameters change.

CW Calibration Test Procedure

The following steps summarize the procedure required to configure the WLAN DUT and the N4010, make the Average Power, and CW Frequency Offset Measurement, and recover the results:

CW Calibration Test Procedure Programming Detail

Using the same steps as the above summary procedure, this procedure shows the required N4010 WLAN DLL commands.

  1. N4010: Setup Frequency, for example, Channel 1 at 2.412GHz, by setting the Frequency property

    Inst.Frequency = 2.412e9;

    // Sets the N4010 Tx / Rx Frequency

  2. N4010: Setup Power Range, for example, 5dBm, by setting the PowerRange property

    Inst.PowerRange = 5.0;

    // Sets the N4010 maximum expected power range to optimize dynamic range

  3. N4010: Setup Max Packet Length, for example, 0.005, by setting the MaxPacketLength property

    Inst.MaxPacketLength = 970e-6;

    // Sets the N4010 acquisition length

  4. N4010: Select Trigger Style to Free Range, by changing the Trigger Style property

    Inst.TriggerStyle = Agilent.N4010.WLanTest.Enums.TriggerStyle.FreeRange;

    // Sets the N4010 trigger style

  5. WLAN DUT: Setup frequency band, for example, 802.11b

    //DUT Specific command to set frequency band

  6. WLAN DUT: Setup channel, for example, channel 1 at 2.412GHz (that is, N4010 = WLAN DUT Frequency)

    // DUT Specific command to set transmit frequency

  7. WLAN DUT: Select transmit power level, for example, -20dBm

    // DUT Specific command to set transmit power

  8. N4010: Initiate the CW Offset Frequency Measurement

    Inst.CwFrequencyOffset_Initiate();

    // Initiates the CW Frequency Offset Measurement

  9. N4010: Initiate the CW Frequency Offset Measurement

    Inst.CwFrequencyOffset_Initiate();

    // Initiates the N4010 CW Frequency Offset Measurement

  10. N4010: Retrieve the CW Frequency Offset Measurement Result

    Result = Inst.CwFrequencyOffset_Result;

    // Returns the N4010 CW Frequency Offset Result

  11. N4010: Initiate the Average Power Measurement

    Inst. AveragePower _Initiate();

    // Initiates the N4010 Average Power Measurement

  12. N4010: Retrieve the Average Power Measurement Result

    Result = Inst.AveragePower_Result;

    // Returns the N4010 Average Power Result