The main form, 8.5 GHz calculation bandwidth

Below you see two versions of the main analyzer form. One with non-linear distortion switched off (open distortion checkbox) on top and below, a version where the non-linear transfer function is selected causing broad inter-modulation.

The maximum number of transmit channels is 16 and their individual frequencies are shown in the top-left list box. The R indication shows that the frequency of that channel is subject to a random frequency walk simulating modulation on the transmit channel. It does not make sense to analyze the PIM performance with fixed transmit frequencies, as all PIM products will in that case always fall on the same frequencies. Modulation of all the transmit channels creates a more realistic result.

The lower spectrum scan shows a zoom of a small portion of the upper spectral display that runs from 0 to 8.5 GHz.  There are two zoom selections possible for this zoom, 9 or 27 MHz. The resolution bandwidth in the zoomed display improves the RBW from 524 kHz in the upper spectral display to 35 kHz in the lower display.

In the picture below, the distortion is switched on and the effects in the spectrum are clearly visible.

The PIM zoomed detectors window. Up to 16 channels can be defined and made active. The green line is the last sweep, the blue line is the max-hold function of all sweeps. When all TX channels have a random walk on the TX frequency, all PIM generated signals will have a continuous changing frequency. With the max-hold function, you can see where PIM signals can fall in the frequency spectrum.