dsp.BurgSpectrumEstimator

(To be removed) Parametric spectral estimate using Burg method

The dsp.BurgSpectrumEstimator System object™ will be removed in a future release. Use pburg instead. For more information, see Compatibility Considerations.

Description

The BurgSpectrumEstimator object computes a parametric spectral estimate of the input using the Burg method. The object fits an autoregressive (AR) model to the signal by minimizing the forward and backward prediction errors (via least-squares). The AR parameters are constrained to satisfy the Levinson-Durbin recursion.

To compute the parametric spectral estimate of the input:

Define and set up your System object. See Construction.
Call step to compute the estimate according to the properties of dsp.BurgSpectrumEstimator. The behavior of step is specific to each object in the toolbox.

Note

Starting in R2016b, instead of using the step method to perform the operation defined by the System object, you can call the object with arguments, as if it were a function. For example, y = step(obj,x) and y = obj(x) perform equivalent operations.

Construction

burgspecest = dsp.BurgSpectrumEstimator returns an object, burgspecest, that estimates the power spectral density (PSD) of the input frame using the Burg method.

burgspecest = dsp.BurgSpectrumEstimator('PropertyName',PropertyValue,...) returns a spectrum estimator, burgspecest, with each specified property set to the specified value.

Properties

`EstimationOrderSource`	Source of estimation order Specify the source of the estimation order as `Auto` or `Property`. If you set this property to `Auto`, the object assumes the estimation order is one less than the length of the input vector. The default value is `Property`.
`EstimationOrder`	Order of AR model Specify the order of AR model as a real positive integer. This property applies only when you set the `EstimationOrderSource` property to `Property`. The default value is `6`.
`FFTLengthSource`	Source of FFT length Specify the source of the FFT length as `Auto` or `Property`. When you set this property to `Auto`, the objects assumes the FFT length is one more than the estimation order. When you set this property to `Property`, the FFTLength property value must be an integer power of two.
`FFTLength`	FFT length as power-of-two integer value Specify the FFT length as a power-of-two numeric scalar. This property applies when you set the `FFTLengthSource` property to `Property`. The default value is `256`.
`SampleRate`	Sample rate of input time series Specify the sampling rate of the original input time series as a positive numeric scalar in hertz. The default value is `1`.

Methods

step	Estimate of power spectral density

Common to All System Objects
`release`	Allow System object property value changes

Examples

Estimate PSD Using the Burg Method

Note: This example runs only in R2016b or later. If you are using an earlier release, replace each call to the function with the equivalent step syntax. For example, myObject(x) becomes step(myObject,x).

x = randn(100,1);
burgspecest = dsp.BurgSpectrumEstimator('EstimationOrder', 4);
y = filter(1,[1 1/2 1/3 1/4 1/5],x); % Fourth order AR filter
p = burgspecest(y); % Uses default FFT length of 256

plot((0:255)/256, p);
title('Burg Method Spectral Density Estimate');
xlabel('Normalized frequency'); ylabel('Power/frequency');

Algorithms

This object implements the algorithm, inputs, and outputs described on the Burg Method block reference page. The object properties correspond to the block properties.

Compatibility Considerations

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