Power level accuracy, low power calibration, Description, Required test equipment – Agilent Technologies E4438C User Manual
Page 128: Power level accuracy, low power calibration -36, Description -36, Required test equipment -36
Adjustments
Power Level Accuracy, Low Power Calibration
4-36
Power Level Accuracy, Low Power Calibration
Description
This calibration adjusts the step attenuator accuracy over the 55 dB to 130 dB internal step attenuator range.
This calibration requires that the Power Level Accuracy, High Power Calibration be performed prior to this
adjustment. The correction value for the 50 dB step attenuator is used in the calculation for each attenuator
step.
An external step attenuator limits the signal level applied to the Low Noise Amplifier (LNA). This protects
the LNA and provides additional control over the signal level applied to the Vector Signal Analyzer (VSA). To
determine calibration values for the internal step attenuator, the VSA makes delta-marker measurements
between the 50 dB reference and each progressively bigger attenuator step. Once the 95 dB attenuator step is
calibrated, the external step attenuator is set to 0 dB and the internal 90 dB step attenuator is used as the
reference.
For frequencies > 2 GHz, a spectrum analyzer down converts the signal generator frequency to 310.7 MHz.
This extends the frequency range as high as necessary and the high frequency LNA is used to amplify the
signal level.
Required Test Equipment
• Agilent 89441A vector signal analyzer with Options AYA, AYH, AY7, AY9, B7A, UFG or UTH
• Agilent 8563EC Option 001 spectrum analyzer
• Agilent 8495G programmable step attenuator (0 to 70 dB)
• Agilent 11713A step attenuator driver
•
See
Chapter 2, “Required Equipment,” on page 1
for details on the following:
— Low Frequency Low Noise Amplifier (LNA)
— High Frequency Low Noise Amplifier (LNA)