Application Note
Configuring The Spectrum Analyzer To Measure Low-Level Signals
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•Application Note: Configuring The Spectrum Analyzer To Measure Low-Level Signals
Introduction
Measuring low-level signals with a spectrum analyzer is a common challenge. The fundamental reason for this is the noise generated within the spectrum analyzer limits the lowest signal level detectable. Even if a user knows the specified noise level of the spectrum analyzer when terminated with a 50Ohm load ("Displayed Average Noise Level" or "Noise Floor"), he or she may not be fully aware of how to properly configure the analyzer to achieve that specification. Also, the settings required to achieve the terminated DANL specification may not be suitable for every application.
The Noise Floor, or Displayed Average Noise Level (DANL), of a spectrum analyzer determines the lowest possible signal level that can be measured by the unit. For example, if one is attempting to measure a signal that is -130dBm, the spectrum analyzer must have a DANL that is lower than -130dBm. Ideally, the measured signal should be a few dB above the DANL in order to be clearly discernable. If the input signal's noise level is greater than the spectrum analyzer's DANL, then the noise level of the input signal will dominate. In this case, nothing can be done to further lower the noise displayed on the unit.
Click Here To Download:•Application Note: Configuring The Spectrum Analyzer To Measure Low-Level Signals
