Dynamic range is a core measure of spectrum analyzer performance, and can signifi cantly affect other core measures such as accuracy and measurement speed. Spectrum analyzers have many different measures of dynamic range, and most of these include noise, specifi cally the analyzer’s own internally-generated noise. Reducing the effective analyzer noise fl oor therefore improves dynamic range and the quality of many measurements. Most spectrum analyzer users are aware that any measurements made near an analyzer’s displayed noise level (within about 20 dB) will be affected by noise. The analyzer’s noise adds to the apparent power of the signal to be measured, producing a result that is somewhat higher than the true fi gure (on average) as shown in Figure 1.