Spectral Measurements

Channel power, bandwidth, mean frequency, median frequency, harmonic distortion

Use obw and powerbw to find the 90% occupied and 3-dB bandwidths of a signal. Compute the mean or median frequency of a power spectrum. Estimate the power over a given frequency band. Measure harmonic distortion. Estimate instantaneous frequency, spectral entropy, and spectral kurtosis.

Functions

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Power and Bandwidth

`bandpower`	Band power
`enbw`	Equivalent noise bandwidth
`instfreq`	Estimate instantaneous frequency
`meanfreq`	Mean frequency
`medfreq`	Median frequency
`obw`	Occupied bandwidth
`pentropy`	Spectral entropy of signal
`pkurtosis`	Spectral kurtosis from signal or spectrogram
`powerbw`	Power bandwidth

Harmonic Measurements

`sfdr`	Spurious free dynamic range
`sinad`	Signal to noise and distortion ratio
`snr`	Signal-to-noise ratio
`thd`	Total harmonic distortion
`toi`	Third-order intercept point

Topics

Measure the Power of a Signal

Estimate the width of the frequency band that contains most of the power of a signal. For distorted signals, determine the power stored in the fundamental and the harmonics.

Measure Total Harmonic Distortion

Measure the total harmonic distortion of a sinusoidal signal.

Featured Examples

Analyzing Harmonic Distortion

Analyze the harmonic distortion of a weakly nonlinear system in the presence of noise.

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Spurious-Free Dynamic Range (SFDR) Measurement

Measure the SFDR of a numerically controlled oscillator and explore the effects of adding phase dither.

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Measuring Signal Similarities

Compare signals with different sample rates, measure delays, and compare frequency content; find a signal in a measurement and determine if it is periodic.