dsp.PeakToRMS System object

Package: dsp

Peak-to-root-mean-square value of vector

Description

The `PeakToRMS` object calculates the peak-to-root-mean-square ratio of a vector.

To compute the peak-to-root-mean-square ratio:

1. Define and set up your peak-to-root-mean-square calculation. See Construction.

2. Call `step` to calculate the peak-to-root-mean-square value for an input vector according to the properties of `dsp.PeakToRMS`. The behavior of `step` is specific to each object in the toolbox.

Construction

`H = dsp.PeakToRMS` creates a peak-to-root-mean-square System object™, `H`, that returns the ratio of the maximum magnitude (peak) to the root-mean-square (RMS) value in an input or a sequence of inputs.

`H = dsp.PeakToRMS('PropertyName',PropertyValue,...)` returns an `PeakToRMS` System object, `H`, with each specified property set to the specified value.

Properties

 `CustomDimension` Numerical dimension to operate along. Specify the dimension as a positive integer along which the peak-to-RMS ratio is computed. The value of this property cannot exceed the number of dimensions in the input signal. This property applies when `Dimension` property is `'Custom'`. Default: `1` `DecibelScaledOutput` Report output in decibels (dB). Set this property to `true` to enable output in dB. Set this property to `false` to report output as a ratio. Default: `true` `Dimension` Dimension to operate along. Specify the dimension along which to calculate the peak-to-RMS ratio as one of `'All'`, `'Row'`, `'Column'`, or `'Custom'`. This property applies when the `RunningPeakToRMS` property is `false`. If you set this property to `'Custom'`, specify the dimension using the `CustomDimension` property. Default: `'Column'` `ResetCondition` Reset condition for running peak-to-RMS mode. Specify the event to reset the running peak-to-RMS as one of `'Rising edge'`, ```'Falling edge'```, `'Either edge'`, or `'Non-zero'`. This property applies when the `ResetInputPort` property is `true`. `ResetInputPort` Enables resetting in running peak-to-RMS mode. Set this property to `true` to enable resetting. When the property is set to `true`, a reset input must be specified in the call to `step` to reset the running peak-to-RMS ratio. This property applies when the `RunningPeakToRMS` property is `true`. Default: `false` `RunningPeakToRMS` Calculation over successive calls to `step`. Set this property to `true` to enable the calculation of the peak-to-RMS ratio over successive calls to the `step`. Default: `false`

Methods

 clone Clones the current instance of the peak-to-root-mean-square object getNumInputs Number of expected inputs to the `step` method getNumOutputs Number of outputs of the `step` method isLocked Locked status (logical) for input attributes and nontunable properties release Allow property value and input characteristics changes reset Reset the running peak-to-root-mean-square object step Compute peak-to-RMS ratio

Definitions

Peak-magnitude-to-RMS Level

The peak-magnitude-to-RMS level is

`$\frac{||X|{|}_{\infty }}{\sqrt{\frac{1}{N}\sum _{n=1}^{N}|{X}_{n}{|}^{2}}}$`

where the l-infinity norm and RMS values are computed along the specified dimension.

Examples

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Peak-to-RMS Ratio of Vector Input

Determine the peak-to-RMS ratio of a vector input.

```in1 = (1:10)'; h1 = dsp.PeakToRMS; y1 = step(h1,in1) ```
```y1 = 1.6116 ```

Peak-to-RMS Ratio of Matrix Input

Determine the peak-to-RMS ratio of a matrix input.

```in2 = magic(4); h2 = dsp.PeakToRMS; h2.Dimension = 'All'; y2 = step(h2, in2) ```
```y2 = 1.6547 ```

References

[1] IEEE® Standard on Transitions, Pulses, and Related Waveforms, IEEE Standard 181, 2003.