Questions tagged [finite-impulse-response]
A finite impulse response (FIR) filter is a type of a signal processing filter whose impulse response is of finite duration.
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Window length clarification - FIR Filter
I'm reading an IEC standard and they say "Group delay of a finite Impulse Response (FIR) filter based algorithm with symmetric or antisymmetric
coefficients is equal to one-half of the window ...
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scipy remez half-band filter DC gain
I'm trying to use scipy.signal.remez to design half-band filters. My understanding is that this targets an equi-ripple criteria to design the filter. What I am ...
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Rounding errors in best linear approximation of a system
I am working on the orthogonal decomposition of a signal to compute the best linear approximation of a system. Given an input signal $x[n]$ and system output $y[n]$, the output can be decomposed into ...
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Minimizing Overshoot of Recursive Least Squares Adaptive Filter in Non-stationary Environment?
I'm using the RLS algorithm for online system identification of a 1D FIR filter. When I simulate my system in response to a small step change in the plant FIR coefficients, the adaptive filter does ...
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FIR filter different implementation method
I'm working on a project using an ESP32 that involves continuously sampling a signal and applying a real-time FIR low-pass filter, then, the filtered samples will be sent to the DAC to reconstruct the ...
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Getting the impulse response of a linear system given white gaussian noise as input and the system's output
I am having trouble with my implementation:
...
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How to Normalize and Quantize FIR Filter Coefficients While Maintaining DC Gain of 1?
I am working with a set of FIR filter coefficients and need to normalize and quantize them while ensuring that the DC gain remains equal to 1.
For example, consider the following halfband FIR ...
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Estimating Impulse Response of System with Exponential Swept Sine (ESS) - scaling problem
I calculated the transfer function of a system in Frequency Domain by division of Y and X. Since I only deal with exponential sweep sines (ESS) as excitation, I want to reproduce the transfer function ...
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Demodulating, filtering, and decimating efficiently
I have a system where I produce a sine wave (with DDS) and feed it into an analog circuit, then digitize the response. I want to measure the amplitude and phase of that response. Sample rate is ...
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CMSIS multiply and accumulate FIR filtering algorithm - concern about length of output
The zero-state response of a filter with impulse response $h[k]$ to an input signal $x[k]$ can be calculated by performing the convolution
$$y[k] = x[k] \ast h[k] \tag1$$
If $x[k]$ has length $m$ and $...
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Pulse-shaping filter for DSSS
In a direct-sequence spread-spectrum (DSSS) transmitter, each symbol is "spread" by a spreading sequence, $\mathbf{s}$. This increases the sample rate by a factor of $L_{s}$, where $L_{s}$ ...
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Best filter for time domain signal
I am sampling a sensor signal at 100 Hz and the useful information from the sensor is encoded in the time domain. I'm looking at peaks, doing integrals etc. from this data. The sampled data can be ...
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Associativity of valid mode convolution
I have three vectors, the first one is $x$ which is of relatively long length, and two kernels $k_1$ and $k_2$ with $\text{len}(k_1) < \text{len}(k_2)$. If I perform full mode convolution (like in ...
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FIR filter: settling time and group delay
I have a question in the context of group delay and settling time in the context of FIR filter, especially for minimum-phase filter.
The settling time for a FIR filter of length N is N-1. Obviously it ...
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Why we can't implement an ideal digital filter in the frequency domain and then anti-transform?
It is well known that a digital ideal low pass filter is not feasible since in frequency domain it's a rect function and in the time domain a sinc, which extends infinitely along the entire time axis ...
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How to design narrow band-pass FIR filter?
I have been attempting to design a digital narrow band-pass filter with following parameters. Sampling frequency $f_s = 10^4\,\mathrm{Hz}$, low cutoff frequency $f_{cl} = 290\,\mathrm{Hz}$ and high ...
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Interpolate the Polyphase data flow using polyphase FIR filter
Suppose we have a system that processes two data branches, $x_1=[11,14]$ and $x_2 =[12,13]$ in polyphase, with a system clock running at 2 Hz. We determine the FIR filter coefficients, which total 8, ...
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Why does nobody talk about the fact that linear phase FIRs are not so linear?
I noticed that in supposedly linear phase FIR filters, the phase is only linear within the main lobe. I have not found anyone else discussing the fact that the phase inverts at every null point ...
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How FIR Linear phase maintained in stop band
When we see a FIR Linear phase filter upto pass band we see the phase response is linear.
But when it enters to stop band whenever there are ripples (like magnitude becoming very low)
I can see a ...
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FIR filter with even-symmetry and odd N taps guaranteed no zero at z=1?
I was given an exercise to prove that there could be no zero for $z=1$ for odd and even symmetric FIR filters with an odd number of $N$ taps. For nonzero coefficients with odd-symmetry this makes a ...
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Creating A FIR Filter From An IR or Room Calibration Data
I'm trying to create FIR filter coefficients from a IR or data from a room calibration capture. I'm hoping to create a filter that compensates for the acoustics of a room.
I'm hoping to put these ...
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What happens to output signal if the filter has a large time delay
I am practicing FIR filter design using the frequency equivalence method. I have designed a lowpass filter with order 20000 with passband 0 - 250 Hz. I send the signal $x(t) = \sin(2\pi t) + \sin(300 \...
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Avoiding data "loss" with FIR filters
I've been studying digital signal processing as it relates to software defined radios. I've been working with the firfilt.py example from https://scipy.github.io/old-wiki/pages/Cookbook/FIRFilter, ...
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System instability when using FIR filter in feedback loop for removing targets in FMCW radar return
I have an FMCW radar I am working on where I am also attempting to remove a specific target from the received signal (before it is sampled by the ADC). To do so, during each FMCW sweep, I am ...
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type 1 FIR filter formulation on SMT solver z3
I have a project that I am currently stuck on. I am trying to find the filter coefficients for a Type 1 FIR filter (even filter order and symetrical) using Z3 with the Python API, but the results I ...
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