Response to Pulses (Peak, Ave, RMS) Bands A/B/C/D Performance Test

This test compares the amplitude of the CW signal to the amplitude of the Aux Generator pulsed signal for each detector.

Test Solutions

There are two test solutions available depending on the existence of the pulse generator calibration data. At the start of the test, TME will detect if there is existing calibration data for the pulse generator. If there is calibration data, it will show as Available in Test Solution 1 as shown in the image below. To use Test Solution 1, the user will first need to run the Pulse Generator Calibration Data Editor Utility which will enter the pulse generator's amplitude corrections and calibration uncertainties from the calibration report/certificate. Test Solution 1 is the preferred solution as explained in the next section.

If there is no calibration data detected for the pulse generator, select Test Solution 2 in the dialog and continue with the test.

TME dialog

Test Solution 1 is the preferred solution

Although either solution can be selected if the calibration data is detected, it is strongly recommended to choose Test Solution 1 and run the Pulse Generator Calibration Data Editor Utility. This solution will use characterized data and uncertainties which will give better margins and lower test uncertainties.

In Test Solution 2, the pulse generator specifications will be used in the uncertainty calculations which will yield greater uncertainty numbers.

Sine Wave Generator Setups

The N7818A E.10.00 release introduced the Schwarzbeck IGUU 2918 as the recommended pulse generator. The Schwarzbeck IGUU 2916 is discontinued but will be supported as the alternative model. The difference in the two models is that the IGUU 2918 model does not have a built-in sine wave generator. To accommodate for this difference, the test will now use a PSG signal generator as the sine wave generator. This signal generator solution will be used with both pulse generator models: the IGUU 2918 model and the discontinued IGUU 2916 model. The setup in previous releases using the sine wave generator in the IGUU 2916 pulse generator will no longer be supported.

Test Details

The measurements are performed with pulsed signals set to the reference PRF rates of 25 Hz (Band A). The Band B PRF will be 100 Hz (Peak), 1000 Hz (RMS), and 500 Hz for the Average detector. The Band C/D PRF will be 100 Hz (Peak), 1000 Hz (RMS), and 5000 Hz for the Average detectors. This test will measure three frequencies: 100 kHz (Band A), 10 MHz (Band B), and 100 MHz (Band C/D).

The Aux generator is used because it can output the higher PRFs required for the Average detector. The Aux Generator output power is 40 dBuv. The Sine wave Generator outputs a 60 dBuV signal at 100 kHz, 10 MHz, and 100 MHz.

The DC Pulse generator is designed to test the Quasi-Peak detector. The pulse area for the Quasi-Peak detector is different than the CISPR pulse area for the Peak, Average, and RMS detectors. An additional pulse area correction must be applied to the final results.

The Pulse Area correction is -20 x Log (A_test/A_CISPR)

Where:

A_Test = The Pulse Area of the test signal (uVs) = 13.5 (Since we are using the DC Pulse, this is the area that is defined by the Q-P detector.)

A_CISPR = The Pulse Area that is defined by CISPR (uVs) for each detector (Peak, Ave, RMS)

• For the Peak Detector, the Pulse Area is defined as 1.4/B_IMP (mVs). The Band A Resolution Bandwidth (-6 dB) is 200 Hz, and B_IMP is 222 Hz. For Band B, the resolution bandwidth is 9 kHz, and B_IMP is 9.18 kHz. For Band C/D, the resolution bandwidth is 120 kHz, and B_IMP is 136 kHz.

• For the Average Detector, the Pulse Area is defined as 1.4/n (mVs). For Band A, n = 25 Hz. For Band B, n = 500 Hz. For Bands C/D, n = 5000 Hz. In CISPR 16-1-1:2019, the definition is changed to use Spectral Density. From Section 3.5, Spectral Density (D) is related to Pulse Area such that D (uV/MHz) = Sqrt(2) x 10^6 x A_CISPR (uVs). Therefore D (dBuV/MHz) = 20 x Log(Sqrt(2) x 10^6 x A_CISPR (uVs)).

• For the RMS Detector, the Pulse Area is defined as 278/SqrtB_3dB) (uVs). The Band A Resolution Bandwidth (–6 dB) is 200 Hz, and B_3dB is 150 Hz. The Band B Resolution Bandwidth (–6 dB) is 9 kHz, and B_3dB is 6.8 kHz. The Band C/D Resolution Bandwidth (–6 dB) is 120 kHz, and B_3dB is 91 kHz. In CISPR 16-1-1:2019, the definition is changed to use Spectral Density. From Section 3.5, Spectral Density (D) is related to Pulse Area such that D (uV/MHz) = Sqrt(2) x 10^6 x A_CISPR (uVs). Therefore D (dBuV/MHz) = 20 x Log(Sqrt(2) x 10^6 x A_CISPR (uVs)).

The Band A Pulse Area Corrections are summarized in the following table:

The Band B Pulse Area Corrections are summarized in the following table:

The Band C/D Pulse Area Corrections are summarized in the following table:

Troubleshooting

You may get an GPIB connection error when using the IGUU 2918.

There is a known issue with certain versions of the Keysight IO Library not recognizing the Schwarzbeck IGUU 2918 pulse generator and therefore causing a GPIB connection failure. There are two work-around methods to correct this error. Refer to the Connecting GPIB Instruments section of Getting Started for more information.

For other troubleshooting tips for this test, click here.

Required Test Equipment

Connection Setups

Click on the links below for images depending on the pulse generator model being used.