there are a few different ways. if you are interested in finding the harmonic distortion of a single (CW) set of stimulus values for your mixer, then you can use the IM Spectrum Converters measurement class (opt 083 + 087). The IM Spectrum converter channel works much like if you had a couple of sources and a spectrum analyzer. you can setup the input and LO signals into your mixer and then set the response range to cover the harmonic frequency you want to measure.

if you are interested in a swept harmonic measurement, then you can simply use a Scalar Mixer/Converter measurement channel (SMC) and set it up just as you would for measuring the conversion loss of the mixer. However, if for example you are interested in the 2nd harmonic of the fundamental IF, then just put a 2 in the input multiplier field of mixer setup. in this configuration, the SC21 measurement will be the ratio of the harmonic power to the RF input power and the OPwr measurement is simply the absolute power of the harmonic signal. If you want to measure different harmonic frequencies, you'll have to setup a different SMC channel for each. The SMC channel has its own calibration wizard, so just run the cal after you have configured the channel and follow the steps.

the other possibility is using the PNA's FOM capability (opt 080). this measurement is better suited for the case where the harmonic frequency is swept and you don't have option 083. In this case, in a standard channel you turn FOM on and setup one source to supply the Input signal and the other source (if you have the dual source configuration) to supply the LO (any number of external sources can also be used). if your mixer is connected between ports 1 and 2, then you'll setup a B measurement and set the receiver range to sweep at the mixer's fundamental IF frequency. with the B measurement you measure the output power of the IF. you then make a copy of this channel and in the copied channel, you need to set the receiver range to the harmonic frequencies and again setup a B measurement, which in this case will be measuring the harmonic power. the ratio of this measurement over the IF power measurement is the harmonic distortion.

for both the IM Spectrum and the FOM measurements, the receivers can be calibrated easily using our new Guided Enhanced Power cal technique.

if you are interested in a swept harmonic measurement, then you can simply use a Scalar Mixer/Converter measurement channel (SMC) and set it up just as you would for measuring the conversion loss of the mixer. However, if for example you are interested in the 2nd harmonic of the fundamental IF, then just put a 2 in the input multiplier field of mixer setup. in this configuration, the SC21 measurement will be the ratio of the harmonic power to the RF input power and the OPwr measurement is simply the absolute power of the harmonic signal. If you want to measure different harmonic frequencies, you'll have to setup a different SMC channel for each. The SMC channel has its own calibration wizard, so just run the cal after you have configured the channel and follow the steps.

the other possibility is using the PNA's FOM capability (opt 080). this measurement is better suited for the case where the harmonic frequency is swept and you don't have option 083. In this case, in a standard channel you turn FOM on and setup one source to supply the Input signal and the other source (if you have the dual source configuration) to supply the LO (any number of external sources can also be used). if your mixer is connected between ports 1 and 2, then you'll setup a B measurement and set the receiver range to sweep at the mixer's fundamental IF frequency. with the B measurement you measure the output power of the IF. you then make a copy of this channel and in the copied channel, you need to set the receiver range to the harmonic frequencies and again setup a B measurement, which in this case will be measuring the harmonic power. the ratio of this measurement over the IF power measurement is the harmonic distortion.

for both the IM Spectrum and the FOM measurements, the receivers can be calibrated easily using our new Guided Enhanced Power cal technique.