# fir's questions - English 1answer

279 fir questions.

### Low pass filtering of an upsampled(zero padded) signal

0 answers, 9 views fir interpolation
I have been working on interpolation in python from quite some time. The input signal is a sinusoid signal sampled at 933KHz. I am upsampling the signal by a factor of 5 and later using an FIR ...

### Complex and nonlinear-phase equiripple FIR filter design with function handle

0 answers, 13 views filter-design fir
User-definable functions may be used, instead of the predefined frequency response functions for @fresp. The function is called from within cfirpm. I 'm using the handle function to adding the group ...

### Calculations resettings and Overlapping estimation technique [on hold]

Please, i need a helpful example to examine the issue of how and when to update, or re-initialize, the computations with SIMULINK or Matlab. For exemple, a first identifier is reinitialized when t1= 0 ...

### 1 Fast optimization for long FIR filters

1 answers, 48 views fir convex-optimization
I need FIR filter lengths in the order of 1e4 and above to obtain reasonable accuracy in desired frequency response. The problem is that optimisation in MATLAB (e.g. fircls or the Optimization Toolbox)...

### How can a RLS algorithm utilise Wiener filter as FIR (M-tap) block?

I'm currently working with a dataset of $5000$ pulses of $N=15000$ samples each. I managed to implement the RLS algorithms with a FIR M-Tap filter such that $M\leq 15000$ ($150$ seems to achieve the ...

### 1 What is the difference between closed form and opened form in z transform

I am new in DSP and I need to have a clear udrastanding about below example. Consider the below $h[n]$ as the impulse response of a system: $$h[n] = a^n(u[n] - u[n-N])$$ ...

0 answers, 108 views fir distortion dithering lfsr
I have an issue which I wasn't able to solve for a few days. I have implemented a polyphase FIR interpolation filter within an FPGA which does interpolate by a factor of 8 or 16 times. I do accept an ...

### 2 Overlap/Chunk processing possible with Zero-phase?

I'm relatively new to DSP and I'm currently investigating FIR filter and IIR filters. From what I've found FIR filters can be implemented efficiently using the overlap-save method, but I was wondering ...

### 2 How to correct phase of Diagonal Volterra kernels obtained with exponential sweep sine?

3 answers, 168 views convolution fir non-linear kernel
I'm trying to model a non-linear system using non-linear convolution with Novak's (2010) synchronized exponential sine weep (SESS) that models them with a Generalized Hammerstein (Volterra diagonal). ...

### 3 How to understand the filter coefficients in FIR filter

3 answers, 49 views filters fir
Here it is the difference equation we have: y(n) = -0.25x(n) - 0.15x(n − 1) + 0.78x(n − 2) − 0.15x(n − 3) - 0.25x(n - 4)I understand that is FIR. The ...

### Amplitude problem by puting 5 FIR in a row

1 answers, 82 views matlab discrete-signals fir
I'm trying to use 5 FIR in a row to improve the S/N ratio on my signal, but I have some difficulties doing it. In fact I have 2 signals, let's call them sig_I and sig_Q. I want to apply my 5 filter ...

### 1 How to compare many bandpass filters (for their signal propogation delay)?

Let's say we have an audio signal sampled at 96 kHz, and we want to compare several bandpass filters to find the one with the lowest rectangular-envelope-propagation-delay (see graph below). The band ...

### 1 How to properly match bit growth of a FIR filter with a reference value

1 answers, 410 views fir deconvolution bitdepth
I am trying to implement a chain of CIC/FIR filters on an ZYNQ FPGA. Using the Xilinx FIR compiler works fine so far but I am unable to properly get all the math. At the moment I have 2 chains of ...

### 1 What is an “innovation filter”?

I'm a math postgrad student working through a paper on eigenvalue decompositions of matrices of FIR filters (used for stuff like total decorrelation, convolutive mixing, MIMO). Towards the beginning, ...

### Implementing an analog approximation of an FIR filter given its impulse response

2 answers, 176 views fir hardware-implementation
Problem: I have the impulse response of a matched filter(therefore its phase and magnitude response. See figure below) of a filter, and I need to implement its response using only off-the-shelf ...

### 1 Parallel Cascaded FIR Filters

1 answers, 28 views lowpass-filter fir bandpass
I have a relatively simple question. I know if you connect multiple LTI systems in parallel, overall system's frequency response is the sum of each LTI system's frequency response. Therefore, what ...

### 1 How to obtain a meaningful group delay graph using matlab

1 answers, 136 views matlab fir group-delay
Problem: I'm trying to analyze the behavior of an FIR filter with the following impulse response/kernel: Using Matlab's function grpdelay(myKernel,length(myKernel)), I obtained the following figure:...

### 1 Design of a complex FIR filter

1 answers, 46 views filter-design fir

### -1 Is this a FIR algorithm?

I'm kind of out of my element here trying to understand this algorithm and I wanted to see if this is a FIR algorithm or not? If this isn't the right place to ask this, can someone point me to a place?...

### Design of FIR filters with arbitrary magnitude and phase responses

1 answers, 74 views filter-design fir least-squares
I found many information in this thesis "Algorithms for the Constrained Design of Digital Filters with Arbitrary Magnitude and Phase Responses",i want to understand it. This question is a ...

### Arbitrary-Response Filter Design

1 answers, 37 views matlab filter-design fir parks-mclellan
I want to design a FIR filter by using 'cfirpm' function , which can i use the group delay and grid frequency, my code is : ...

### FIR filter design and implementation meaning [closed]

1 answers, 36 views filters convolution fir
What is the output of the convolution meaning which is used in the FIR filter? how can conclude the output of the FIR filter in the output according to the input $x[n]$?

### 2 Mean delay for a M tap harmonically weighted filter

I am trying to derive the mean delay for $M$ filter taps harmonically weighted: $$y[n] = \frac{M\,x[n] + (M-1)x[n−1]... + 1 \cdot x[n−M+1]}{\tfrac12 M (M + 1)}$$. For a uniformly weighted filter, I ...

### 4 Spectral baseline distortion simulation - Bruker smile

1 answers, 98 views fir distortion
I work with Magnetic Resonance Spectroscopy data. Data (complex signals) obtained from Bruker scanners (one of the biggest manufacturers of MRS scanners) start with an important group delay - around ...

### 8 Convert a FIR to an equivalent IIR

Is there a way to convert a FIR to an IIR filter with the most similar behavior?

### FIRFilter with low cut-off compared to sampling frequency

Sorry if my question is some FIRFiltering basics, but I couldn't find a specific answer after some search. I am trying to design a decimating low pass filter in C (actually in OpenCL with GPU) with ...

### -1 Phase response approaches towards the zeros

1 answers, 40 views filter-design phase fir linear-phase
Phase response is the relationship between the phase of a sinusoidal input and the output signal passing through any device that accepts input and produces an output signal, such as filter.https://en....

### The grid frequencies In the design of a digital filter

I want to find many difference 'h' with same group delay and length filter using this code : https://gist.github.com/mattdsp/17f508d2b368db61f47689e4622d8841/c1518f22a5aa451951601b56c5d9f72743868bfe ...

### FIR Impulse response & transfer function

1 answers, 67 views fir impulse-response transfer-function
I am working though a dsp past paper and I have come across the questions "find the impulse response in the time domain" & "find the transfer function in the time domain" I know its really simple ...

### Phase response of a FIR Hilbert transformer

3 answers, 42 views phase fir hilbert-transform
The graph below shows a linear phase response of FIR Hilbert transformer with a constant diff of -0.06135923. I am not sure if I understand the concept of the phase response correctly, but as the ...

### 2 How to design very narrow band, very sharp low pass filters - Only DC needed?

5 answers, 3.071 views lowpass-filter decimation fir
I am using a DSP processor to sample signals at 108kHz and I only want to get the DC part out of it. Such a high sampling rate is used because I want to use oversampling to reduce quantization noises. ...

### 1 Is it possible to get the envelope of a signal via FIR filter?

1 answers, 60 views fir finite-impulse-response envelope
I was reading an article about ultrasonic signals, and I read in it that it is possible to get the envelope of a signal by using a band pass FIR filter. My question: Is it possible to get the envelope ...

### IIR (non linear phase) filters

As you know, a nonlinear phase filter (in passband), distorts the frequency contents of passband region of signal. In general, Why do we use such filters in the case they cause distortion in the ...

### 1 When Is a Power of 2 FFT Slower than Smaller Sized Non Power of 2 FFT in MATLAB

Knowing that computing an FFT is faster if the amount of samples is a power of 2 I have always tried to pad the inputs to Matlab's FFT with zeros until the next power of 2 is achieved. Matlab's ...

### How to remove 750Hz sinusoidal background from audio using FIR filter? [duplicate]

0 answers, 25 views matlab fir
Kindly help me to design a FIR filter for eliminating the 750 Hz sinusoidal beep from audio. I shall be thankful to you

### What is meant by Two pass FIR Filter?? (A basic question)

1 answers, 68 views filter-design fir
I have a confusion about what does a two pass FIR (bandpass) filter with order 40 means?? Passband frequencies are [8 13]. Type 2 FIR is same as two pass?? I have check some previous literature ...

### 2 Discrepancies between FFT-based Hilbert Transform and FIR filter results

1 answers, 133 views phase fir hilbert-transform
I compared the results of Hilbert Transform as provided in scipy.signal.hilbert() (which is uses I/FFT as you can see in the source code) with its approximation implemented as FIR filter using coeffs ...

### Properties of Optimization Techniques in Filter Design

I have this design , Can you tell me about the type of filter and the algorithm just viewing this design, or should there be other information?

### 1 No-lag causal bandpass filter kernel formula

3 answers, 84 views fir sound bandpass
Can anyone point me towards a formula for a good (for any values of "good") no-lag causal bandpass filter? I am doing sound processing and I need to identify starting points of certain sounds (target ...

### Applying multiple IIR and FIR filters at once

1 answers, 59 views infinite-impulse-response fir
I would like to appy multiple filters to a signal at once. Let's assume I got two frequency bands I want to extract. I compute a Butterworth Filter for 300-500Hz and one for 700-800Hz. I would like to ...

### Differences between Matlab resample() and CMSIS decimate_f32()

0 answers, 88 views matlab fir decimation attenuation
I am pretty new to DSP and I need some help to pinpoint my mistake. I am using Matlab to simulate an embedded environment. I have three signals all centered on 50Hz (6.4KHz sampling rate) which have ...

### About how to increase the FIR filter sampling frequency in FPGA? And what is the tradeoff of increasing the sampling frequency?

1 answers, 52 views filter-design fir
I am trying to implement a FIR filter on FPGA and trying to have a solid understanding of the FIR filter tap delay and sampling frequency. Does the “one tap” delay equal to “1/Fs (sampling frequency)”...

### Compensating for group delay in FIR with symmetrical coefficients

1 answers, 56 views matlab fir group-delay
Suppose I have a sinusoidal signal of 50Hz sampled at 6.4kHz and I wished to filter it at: Band pass: 160Hz, Bands stop: 800Hz, Apass:0.1db, Astop: 106db For a FIR filter order of 40 I would get 41 ...