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Difference between revisions of "NVGate Output Signals"
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=====Multi-sine===== | =====Multi-sine===== | ||
Multisine is computed by adding sine signals whose frequencies are power of two sub-modules of sampling frequency. This means that multisine output block includes all discrete sine waves of FFT spectrum of corresponding block size and resolution. Multisine has the advantage of showing no leakage effect in FFT as all sine waves are exact periods of the trigger block for FFT computation. The most appropriate FFT weighting window to be used is “uniform” window. Multisine generators work on a sample block basis, it means signal blocks are repeated identically over time. | |||
Used to generate and configure up to 2 multi-sines. The multi-sine is computed by adding sine signals whose frequencies are power of two sub-modules of sampling frequency. So with the FFT analyzer, each sine signal can be exactly at an analysis frequency line and there is no leakage due to analysis window. Due to its specific structure, using a rectangular analysis window for FFT analysis on a multi-sine excitation is recommended. | Used to generate and configure up to 2 multi-sines. The multi-sine is computed by adding sine signals whose frequencies are power of two sub-modules of sampling frequency. So with the FFT analyzer, each sine signal can be exactly at an analysis frequency line and there is no leakage due to analysis window. Due to its specific structure, using a rectangular analysis window for FFT analysis on a multi-sine excitation is recommended. | ||
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<br>After reactivation:<br><br> | <br>After reactivation:<br><br> | ||
[[Image:Resources_output_06.png|framed|none]] | [[Image:Resources_output_06.png|framed|none]] | ||
Phase relationship between sine waves is selected at selection of setting and will not change unless “random” setting is changed back and forward. After “random” is selected phase relationship is defined (randomly for the first block) and repeated identically for each signal block of N lines. Phase relationship for all multisine generators will be different as random setting activation is made at different moment in time and applied for different generator objects. Two blocks of multisine random phase of the same generator are 100% correlated. | |||
Two mulitsine random phase generators are not correlated. | |||
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|Each sinusoid has the same original phase even after multi sine deactivation/activation.<br> | |Each sinusoid has the same original phase even after multi sine deactivation/activation.<br> | ||
[[Image:Resources_output_07.png|framed|none]] | [[Image:Resources_output_07.png|framed|none]] | ||
Multisine phase relation if fixed and will be the same each time setting “fixed” is selected. | |||
Phase relationship is the same for all multisine generators meaning that signal blocks will be the identical between any multisine generators of the same setting. Multisine fixed phase generators are 100% correlated. | |||
<br> | <br> | ||
|}<br clear="all"> | |}<br clear="all"> | ||
'''Burst setting''' in Multisine generators will shorten time during which output signal is active despite signal block being of the same length. | |||
All bandwidth frequencies are present in each burst but may not be complete cycles as block period is truncated. Two bursts being identical (respectively fixed or random phase) they are 100% correlated. Two burst random from two separate generators will not be correlated signals. | |||
=====Random noise===== | =====Random noise===== | ||