Questions tagged [highpass-filter]

A high-pass filter is a device that passes high frequencies and attenuates frequencies lower than its cutoff frequency.

Filter by
Sorted by
Tagged with
2
votes
2answers
893 views

What is the name of these simple filter algorithms?

I found some snippets of code on the internet that are really simple signal filters. Unfortunately there wasn't much info to back it up. Using Google I've found similar code, but none of it backed up ...
10
votes
2answers
1k views

Filtering of streaming audio

Given something like 103 data points ($N=103$), a DFT will give back 103 frequency values. Then to do something like filtering the high frequencies involves setting the high frequency values from the ...
7
votes
4answers
3k views

Filter size vs. FFT size and Overlap add

First of all I would like to say that : I'm new to DSP and in a "learning curve" hence the "basicness" of my questions. I've read as many posts/articles as possible on the ...
5
votes
4answers
19k views

Designing High Pass Filter to Remove DC Offset from a Signal

I want to design a high pass filter (f0*S/1+f0*S) in order to remove the dc offset from a signal ? (i.e. how to choose the frequency f0). Thanks, Hacene Ps : the filter is for MATLAB implementation, ...
4
votes
2answers
13k views

How to produce a high-pass filter from a low-pass one?

I already have a low-pass filter and want to remove the DC offset of a signal with a high-pass one. I guess you can subtract a low-pass filtered signal from the original signal and the result is a ...
2
votes
3answers
3k views

Filter design - Rules of thumb regarding ratio of sampling and stop/pass frequency

The issue: I have a signal in the time domain sampled at 51.2KHz. I want to apply a highpass filter with a pass frequency of 20 Hz. The problem: Using Matlab to do that, the design of the filter ...
14
votes
2answers
3k views

Is a high-passed signal the same as a signal minus a low-passed signal?

My question is, if I want to high-pass a signal, is it the same as low-passing a signal and subtracting it from the signal? Is it theoretically the same? Is it practically the same? I have searched (...
6
votes
1answer
12k views

How is the lowpass to bandpass transformation derived?

I'm using a lowpass to bandpass filter transformation: $$ s \leftarrow Q \left( \frac{s}{\omega_0} + \frac{\omega_0}{s} \right) $$ Based on the wiki article: http://en.wikipedia.org/wiki/...
10
votes
3answers
6k views

Is it correct to subtract a low-pass filtered signal from the original signal and use the result as a "high-pass"?

I am having a hard time trying to find documentation to implement band-pass or high-pass filter with python/scipy/numpy. I can easily create and apply a low-pass filter, though, so I ask: Would it ...
2
votes
2answers
4k views

Mathematical Proof of Complementary Filter?

Having found some unofficial sources on Complementary Filter (Thousand Thoughts Sensor Fusion and The Balance Filter by Shane Colton), I wish to work out its rigorous mathematical proof. The ...
8
votes
2answers
1k views

complementary IIR filters

I would like a pair of complementary IIR filters (lowpass/highpass). By complementary, I mean, when the output from the two filters is summed, the original signal is recovered. I thought I could build ...
2
votes
2answers
1k views

3 dB cut-off frequency of first-order IIR high-pass filter

As descipbed in this great answer (thank you Matt L.), the suggested exact formula was very precise. I need a first order high-pass with similar precision. EDIT: (clarification) The low-pass filter ...
1
vote
2answers
158 views

Envelope analyis basic question

I have a vibration signal sampled at 25.6 kHz, and I want to perform Envelope Analysis on it. "Vibration-Based Condition Monitoring of Wind Turbines" by T. Barszcz has the following figure: I ...
0
votes
1answer
98 views

Simulate butterworth filter with initial condition of state vector in R

I'm working in R with the packages signal and control (don't know wether these are even the best for my use case). I have a high ...