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Power bandwidth

`bw = powerbw(x)`

`bw = powerbw(x,fs)`

`bw = powerbw(pxx,f)`

`bw = powerbw(sxx,f,rbw)`

`bw = powerbw(___,freqrange,r)`

```
[bw,flo,fhi,power]
= powerbw(___)
```

`powerbw(___)`

specifies
the frequency interval over which to compute the reference level,
using any of the input arguments from previous syntaxes. `bw`

= powerbw(___,`freqrange`

,`r`

)`freqrange`

must
lie within the target band.

If you also specify `r`

, the function computes
the difference in frequency between the points where the spectrum
drops below the reference level by `r`

dB or reaches
an endpoint.

`powerbw(___)`

with no output
arguments plots the PSD or power spectrum in the current figure window
and annotates the bandwidth.

To determine the 3-dB bandwidth, `powerbw`

computes
a periodogram power spectrum estimate using a rectangular window and
takes the maximum of the estimate as a reference level. The bandwidth
is the difference in frequency between the points where the spectrum
drops at least 3 dB below the reference level. If the signal reaches
one of its endpoints before dropping by 3 dB, then `powerbw`

uses
the endpoint to compute the difference.

`bandpower`

| `obw`

| `periodogram`

| `plomb`

| `pwelch`

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