FFT Properties - Features

FFT Properties can demonstrate what is the property of the signal itself and what is the property of FFT transformation. With the the signal generator built-in the user can gain insight in to the relation between the displayed signal and the actual formula used to generate it. For those reasons a FFT tutorial is included with FFT Properties with some of the signal processing basics the can be demonstrated in FFT Properties.

The user can also listen to what he is looking at. Although many sophisticated methods have been developed to analyze signals, human ear is still an analyzer beyond compare.

FFT Properties also comes with an interesting interpretation of the DFT formula. Included is also a very compact introduction to wavelet based signal analysis. Together with the The DSP for MtxVec, the user has the option to design his/hers own frequency analyzer.

FFT Properties offers a simple interface with high level of automatization for frequency analysis of real world signals. It enables the user to quickly browse through the frequency spectrums of the signal records, without the need to worry about chart scaling or axis labeling, with or without logarithmic axis.The output in high quality enhanced metafile format is just a click away. Very good printing capabilities allow the user to quickly print large amounts of processed signal records. Separate chart templates for screen and printer make allow different colors and formatting for the screen and paper. The features were designed for pattern recognition applications, where a huge number of samples must be examined to find some rules of behavior. The application will be continuously updated towards handling huge amounts of data and support for the most well known DAQ hardware.

A comprehensive set window functions also include two parametric windows. Kaiser and Chebyshev. They allow an increased control over spectral leakage behavior. High zero padding factors result in smooth peak approximations and in higher frequency and amplitude accuracy. The user can interpolate selected peaks in frequency, amplitude and phase and achieve substantialy better accuracy without the need to change the spectral resolution and without zero padding. Such high frequency accuracy also allows phase measurement directly from the spectrum. To further enhance this feature a special set of peak tracing functions has been used. The accuracy of time-frequency tracing of a single peak is also very high. Each of these features can be tested with the signal generator build in to FFT Properties.

Allows multirate decimation and interpolation in single pass. Generates hilbert transformers. Low-pass, band pass, high pass, Band stop.

Auto-correlation, Cross-correlation, Network functions (cross spectral analysis). Phase, Real, Imaginary, Power, Amplitude spectrum, THD, Noise THD, Cepstral analyis, Discrete cosinetransform.

FFT Properties feature higher order spectral analysis. This includes the calculation of bispectra and bicoherence. This two methods allow the detection of quadratic phase coupling. Single line based analysis of the surface is also included. The HOS methods are especially useful in testing the hypothesis of single peaks being higher harmonics, general type multiplication based or stand alone. This information allows much deeper analysis of the contents of the frequency spectrum. In order to help detect and test for higher harmonics and multiplicative components three special peak marking modes are used, that can also make use of interpolation. And because of direct phase information the guesses about interaction of spectral components can also be made directly from the frequency spectrum.

FFT Properties include full wavelet decomposition scheme. This is not wavelet packet analysis, but general purpose signal analysis with wavelets has been made very user friendly. Wavelets can be used without any special preknowlidge of the extensive math behind them.