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Difference between revisions of "NVGate FFT"
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→FFT analysis
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* '''Range''': the FFT plug-in frequency range. The analyzer sampling frequency divided by 2.56 limits this range, and the minimum is obtained by dividing this limit by 50000. For example, if the analyzer sampling frequency is 51,2kS/s, then the max range is 20 kHz and the min is 400mHz. In post analysis mode, the Max Bandwidth setting from the Player plug-in provides the analyzer sampling frequency by multiplying the value by 2.56 (ex: if max bandwidth = 20 kHz then the analyzer sampling frequency is 51.2kS/s), otherwise, the analyzer sampling frequency is provided by the input sampling setting from the Front end plug-in input setting sub-module. | * '''Range''': the FFT plug-in frequency range. The analyzer sampling frequency divided by 2.56 limits this range, and the minimum is obtained by dividing this limit by 50000. For example, if the analyzer sampling frequency is 51,2kS/s, then the max range is 20 kHz and the min is 400mHz. In post analysis mode, the Max Bandwidth setting from the Player plug-in provides the analyzer sampling frequency by multiplying the value by 2.56 (ex: if max bandwidth = 20 kHz then the analyzer sampling frequency is 51.2kS/s), otherwise, the analyzer sampling frequency is provided by the input sampling setting from the Front end plug-in input setting sub-module. | ||
* '''Resolution:''' This is a fixed setting, for information only. It displays the frequency span between two points of a spectral result. The FFT resolution is obtained by dividing the FFT frequency range by the resolution minus 1. For example if the FFT Range is 20 kHz and the resolution is 401 lines, then the frequency span is: 20000 / (401 - 1) = 20000 / 400 = 50Hz. | * '''Resolution:''' This is a fixed setting, for information only. It displays the frequency span between two points of a spectral result. The FFT resolution is obtained by dividing the FFT frequency range by the resolution minus 1. For example if the FFT Range is 20 kHz and the resolution is 401 lines, then the frequency span is: 20000 / (401 - 1) = 20000 / 400 = 50Hz. | ||
* '''Overlap''': Defines the amount of overlap of input signals between two successive FFT computations, from 0% to 99.99%. When the overlap exceeds 99%, NVGate | * '''Overlap''': Defines the amount of overlap of input signals between two successive FFT computations, from 0% to 99.99%.<br> | ||
Note: When the overlap exceeds 99%, NVGate does not inform if you lost real-time. At this moment, NVGate is performing as fast as it can by taking the last trigger block than can be compute by the processor. | |||
* '''Number of lines''': The FFT number of analyzed lines. There are seven possibilities: 101, 201, 401, 801, 1601, 3201 or 6401 lines. | * '''Number of lines''': The FFT number of analyzed lines. There are seven possibilities: 101, 201, 401, 801, 1601, 3201 or 6401 lines. | ||
* '''Trigger Frequency:''' This setting is only available when the ''FFT x/Average/Domain ''setting is "Synchronous". The value can be chosen from the FFT Frequency range; this frequency is the phase reference: each FFT block is recomputed so that the phase of the frequency chosen is 0. | * '''Trigger Frequency:''' This setting is only available when the ''FFT x/Average/Domain ''setting is "Synchronous". The value can be chosen from the FFT Frequency range; this frequency is the phase reference: each FFT block is recomputed so that the phase of the frequency chosen is 0. | ||