Extract Multiple Tone Information VI
- Updated2025-07-30
- 3 minute(s) read
Returns the frequency, amplitude, and phase for each signal tone whose amplitude exceeds a specified threshold. Wire data to the time signal in input to determine the polymorphic instance to use or manually select the instance.
The input signal can be real or complex and single-channel, in the form of a waveform, or multichannel, in the form of an array of waveforms. If you wire an array of real waveforms to time signal in, LabVIEW selects the Extract Multiple Tone Information N Chan instance by default. If you wire an array of complex waveforms to time signal in, LabVIEW selects the Extract Multiple Tone Information N Chan (CDB) instance by default.
A real multiple tone signal can be expressed as shown in the following equation:
where Ai, fi, and φi are the amplitude, frequency, and phase, respectively, of the ith tone of a multiple tone signal with N tones and Fs is the sample rate in samples per second of the input waveform signal.
A complex multiple tone signal can be expressed as shown in the following equation:
where Ai, fi, and φi are the amplitude, frequency, and phase, respectively, of the ith tone of a multiple tone signal with N tones and Fs is the sample rate in samples per second of the input waveform signal.
For a real signal, the frequency range is (min frequency, max frequency) = (0, Fs/2). For a complex signal, the frequency range is (min frequency, max frequency) = (–Fs/2, Fs/2).
Examples
Refer to the following example files included with LabVIEW.
- labview\examples\Signal Processing\Waveform Measurements\Complex Multi-Tone Measurements.vi