Fader Settings

Using any of the predefined configuration types listed below, you can add real-time fading scenarios to model the multipath propagation and fading that signals encounter as they traverse the real world. You can apply standard fading models or use custom path configurations, modify antenna settings (MIMO only), and adjust correlation matrixes to thoroughly test transmitter or receiver performance of your DUT or subsystem.

For descriptions of large and small scale fading types and spatial characteristics that affect fading correlation in MIMO channels, refer to the About Fading topic.

In all of the following configuration types, the number of available channels depends on the hardware and licenses installed in your instrument.

Master Setup (Generate and Fade)	example	configures up to two independent channels with standard or custom fading scenarios. All fading channels are controlled in a single Master Setup.
Master Setup (Single-User MIMO)	example	configures MxN MIMO channels with standard or custom fading scenarios where all the channels carry data for/from the same user. Since there is a single user, there is a single Master Setup.
Master Setup (Multi-User MIMO)	example	configures MxN MIMO channels with standard or custom fading scenarios that carry the data of different users multiplexed onto a single time-frequency resource to multiple base station antennas. Each user will have its own Master Setup.
Master Setup (Fade-ext in)	example	uses data from an external source (MXA, PXA, EXA, 8960, or custom device) to configure independent channels with standard or custom fading scenarios. All fading channels are controlled in a single Master Setup.
Master Setup Single-User MIMO (ext in)	example	uses data from an external source (MXA, PXA, EXA, 8960, or custom device) to configure MxN MIMO channels with standard or custom fading scenarios where all the channels carry data for/from the same user. Since there is a single user, there is a single Master Setup.

Run-time Adjustment of Fading Parameters

For 1 Channel Generate and Fade or 1 Channel Fade (ext in) configurations:

When Dynamic Fading is not enabled, all Fader parameters (except Random Seed and Dynamic Fading), including the number of paths, are run-time adjustable from the user interface or through SCPI commands while the waveform is playing .

If n is the initial number of enabled paths, you can increase the number of paths to 6 (n ≤ 6), 12 (6 < n ≤ 12), 18 (12 < n ≤ 18) or 24 (18 < n ≤ 24).