MM-wave Noise Measurements Under Nonlinear Conditions

Among a class of noise measurements of interest are those where a (pseudo-) deterministic drive is applied to a DUT and the noise power, in some spectral sub-region, or more generally, is measured. As higher power mm-wave applications proliferate, that measurement type becomes increasingly of interest at higher frequencies where wider bandwidth analyses are needed and the measurement sensitivity-linearity trade-off can be more challenging. A setup will be presented and exercised making these measurements up through the E- to D-band range with 200 MHz of instantaneous bandwidth and a noise sensitivity of -75 dBm absolute with a DUT output level of 10 dBm. Several DUT responses will be examined to study the noise distribution with power and signal type.