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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.


bandpowerBand power
enbwEquivalent noise bandwidth
meanfreqMean frequency
medfreqMedian frequency
obwOccupied bandwidth
powerbwPower bandwidth
sfdrSpurious free dynamic range
sinadSignal to noise and distortion ratio
snrSignal-to-noise ratio
thdTotal harmonic distortion
toiThird-order intercept point


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.

Analyzing Harmonic Distortion

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

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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