longpass

Filter short distances by means of a distance-domain lowpass FIR filter (longpass)

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Syntax

X = longpass(t,S)
X = longpass(t,S,rpass)
X = longpass(t,S,rpass,st)

Parameters

• t - Time axis (N-element array)
• S - Signal (N-element array)
• rpass - Passband distance (scalar)
• st - Transition band steepness (scalar)

Returns

• X - Filtered signal (N-element array)

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Description

X = longpass(t,S)

Applies a lowpass filter to the signal S with a N-point time axis t to suppress any distances below 1.5 nm.

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X = longpass(t,S,rpass)

The passband distance can be specified in nm by rpass. The transition band is computed according to a steepness of 0.8.

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X = longpass(t,S,rpass,st)

The steepness st can be passed as well as a value between 0 and 1.