Questions tagged [equalizer]
The equalizer tag has no usage guidance.
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Zero forcing equalizer matrix
I am looking for an explanation of the matrix used in the Zero-Forcing equalizer, what its rows and columns represent, and why we focus on the middle row?
In the zero forcing we use $2N+1$ samples ...
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decision feedback equalizer building blocks (from Adaptive Filters: Theory and Applications” a book by Behrouz Farhang-Boroujeny)
Here you can see building blocks of DFE from "Adaptive Filters: Theory and Applications” a book by Behrouz Farhang-Boroujeny in chapter 17.
Figure 17.9 shows the overall building blocks of DFE ...
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GRC implementation for IQ data acquisition of 2-GFSK Radio
I am trying to design a 2-GFSK receiver for acquiring IQ symbols. The aim is to implement the entire receiver chain but the decision stage.
The 2-GFSK waveform is being generated by a standard IoT ...
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Equalization with FSK
What are the downsides of using an LMS (or least squares) equalizer with FSK signals? What are the tradeoffs on doing equalization pre-demoduation vs post-demodulation?
Most literature I can find ...
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request pointers on beginner DSP board for making an EQ simulating hearing aid prescription with TV sound
I want to make an equalizer set to similar frequency cut-boost according to the results from the graph from hearing test, where an audiometrist will play tones of various frequencies at various ...
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LMS algorithm: Training and tracking phase
I'm trying to implement a fractionally spaced equalizer to mitigate the effect of ISI on the signal. The block scheme that I'm following is:
I'm using the LMS algorithm to update the tap weights. In ...
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Fractionally spaced equalizer - LMS algorithm
I am doing a project in MATLAB about the fractionally spaced equalizer. The method that i have chosen to update the tap weight coefficients is the LMS algorithm. Here is the block scheme that i have ...
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Fractionally spaced equalizer using LMS algorithm
I am doing a project about the fractionally spaced equalizers on matlab. The goal is to mitigate ISI on the signal using the LMS algorithm to update the tap weights of the FSE. Below i have uploaded ...
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fractionally spaced channel equalizer code [closed]
I want to write a program in matlab for an adaptive fractionally spaced equalizer with lms algorithm.consider each packet with 150 bits that 25 first bits are pilot and used to train weights of the ...
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Central frequencies of band filters with cut-offs at 0 and the sampling rate
I'm trying to configure AutoEq for SuperEQ. The latter was originally a Winamp DSP, but now it's used in foobar2000 and DeaDBeeF.
AutoEq requires a list of central frequencies and Q-factors for ...
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Least Squares Solution Using the DFT vs Wiener-Hopf Equations
Least Squares channel estimation (or equalization) can be accomplished using the "Wiener Hopf Equations", or the Discrete Fourier Transform. Both appear to be least squares solutions. How do ...
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Time domain frequency "loudness" isolation
There is a very useful tool in my DAW which allows me to isolate groups of "loudness" within the frequency domain. Basically, any bin greater than some min, less than some max. It makes it ...
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Should we use Maximal ratio combining and an equalizer together?
I have confusion on MRC(Maximal Ratio Combining) method which I would like to clarify. An example is where I have 1 transmit antenna and 4 receive antennas. The concept of MRC is to combine all the ...
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Feedforward equalizer MMSE vs ZF: I get ZF performs better than MMSE, why is that?
So I am doing some experiments on comparing MMSE and ZF performance. Here is the description of my problem setup:
Consider a pulse response $p_{tilde}$ which is equal to:
[7.41283693728174e-06
-6....
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Requirements on Signal Spectrum for Fractionally Spaced Equalization
I'm constructing an ultrasonic communication system and I am struggling with the correct parameters for my receiver.
In baseband, my channel input signal $x(t)$ has infinite bandwidth, since I use a ...
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Square Root MMSE
Could anyone please explain how to perform the derivation of the square-root MMSE equation using an extended channel matrix H (as it is said in the "A LOW COMPLEXITY SQUARE ROOT MMSE MIMO DECODER&...
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How does zero forcing equalizer work for consecutive pulses?
If in a digital communication system consecutive pulses are sent over a channel, to avoid ISI, a raised cosine filter is used for pulse shaping. If I understand correctly, then this graph taken from ...
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Why does adding a high-pass or low-pass EQ increase volume?
The following three screenshots show the max volume levels (indicated above the VU meter) of Cuckoo by Tipper if played with:
No EQ: -0.5db Headroom
High Pass EQ: +2.5dB over
Low Pass EQ: +0.4dB ...
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Understanding MMSE equalizer equation
I have read many online materials and journal paper where the equation for MMSE equalizer is given as:
$G_{MMSE}$ = $H^H(HH^H+\nu^2I )$
where $H$ is the channel, $H^H$ is its hermitian. $\nu^2$ is ...
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Peaking filter (loudness) cutoff frequency in an equalizer
An equalizer we have consists of Loudness ,Bass ,Mid and Treble .The loudness is nothing but a Peaking filter with cutoff frequency 20Hz .I read this in a book that outlines the EQ design.
I was ...
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where we use estimation and detection in communication system?
I read from the book that we use estimation when we are dealing with analog signal or continuous random variable and the term detection when the transmitted signal is a discrete value even if a ...
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Mathematical expression of Multicarrier frequency equalizer
I have a signal $X$ with length of $N$, multiplied with any unitary matrix, i.e the transpose of DCT matrix as:
$x = D' X$
where $D'$ is the transpose of the of DCT matrix. Then let's add $CP$ guard ...
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Coefficients of a Zero Forcing linear equalizer for infinite length input
Given a discrete-time white noise model:
$$y_k = \sum_{i=0}^{\infty} \alpha^{-i}a_{k-i} + \eta_k$$
where $E(|a_k|^2)=2$, $|\alpha|>1$, $\eta_k$ are uncorrelated zero mean random variables with $E(|\...
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MATLAB model for equalizer using LMS algorithm adaptive filter and unexpected output curve
The MATLAB code below is for equalizer using lms algorithm adaptive filter and then plotting MSE (Mean Square Error) Vs Iteration numbers
...
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How to choose a fixed adaptation step for decision feedback equalizer
How do I choose $\mu$ - a value of a step size for adaptation in a decision feedback equalizer (DFE) with adaptive reference control (ARC)? For a regular adaptive FIR filter an adaptation step depends ...
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Study materials for Decision feedback equalizer
Looking for books, course notes/slides, or some tutorials on decision feedback equalizers with in-depth details.
I appreciate your help.
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How do software equalizers work?
Recently, I have been studying IIR and FIR filters, and trying to create a parametric equalizer using a microcontroller. More specifically, I use the ADC on it to sample the audio at about 44 kHz, and ...
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ZP-OFDM vs. CP-OFDM channel equalization
Now, I am working on OFDM equalization, according to what I understood, Adding CP into the OFDM block change the convolution from linear to circular. That circular convolution enables using point-wise ...
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Distortion of OFDM signal when using RRC filter
I am trying to transmit OFDM signal in pass-band based on RRC filter, but what I noticed that the signal before the RRC filter is completely different compared with signal after the RRC filter (It ...
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What's the computational complexity of MMSE equalizer in OFDM system
As I know that in case of one tap OFDM equalizer, (ZF equalizer), we should have $N$ division complexity since we divide every subcarriers by its correspondent channel tap in frequency domain.
But I ...
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How to implement Minimum mean-squared error (MMSE) equalization?
I have the channel estimation and noise power estimation and I need a matlab implementation of time domain siso channel Equalization.
Theory:
Consider the FIR filter of length $N+1:$
$$
\hat{s}_{k}...
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Is DFE equalizer always blind or can we use reference signal?
I have made a blind DFE Equalization, I mean decision directed .
But I am not sure how to make an implementation based on reference signal known by receiver and emitter. In the back forward filter ...
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What are decision feedback equalizer advantages over linear eq?
I am studying linear and DFE equalization theory. So, the books and the Internet are saying, that linear equalizer uses to inverse z-domain channel function. That means that fir in z-domain with $H(z)$...
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How to use matlab toolbox for 2qam dfe equalizer?
I made Channel equalization with matlab,
You can find the code below.
...
user47976
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Whitening Matched Filters for Equalizer
I was looking at the answer Whitened Matched Filter. It mentions that in case of ISI channel, we can use $g^∗(−t)$ as matched filter. For ISI channel, $r(t)=c(t)∗s(t)+n(t)$ where $r(t)$ is the ...
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Approximate IIR filter with FIR filter with energy restrictions
Hi I was presented with this problem I would like some guidance to solve:
I am given the following DT channel model:
$$C(z) = 1-0.3z^{-1}$$
I am first asked to design an IIR linear zero forcing ...
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Channel estimation and interpolation by vector in OFDM
I have V-OFDM system (Vector OFDM) where every symbol is organized as in below figure:
The black cirles are pilots and white circles are data. First, iFFT operation it taken per column, and then ...
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Frequency-specific Delay?
So an equalizer manipulates the gain of certain frequencies by use of a variety of filters, as we all know. But is there a way to manipulate delay in a frequency-specific manner?
A parametric ...
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Is MMSE equalizer necessary?
For observation $y$, channel coefficient $h$ and gaussian noise $w \sim \mathcal{CN}(0,\sigma^2)$,
$$y = hx + w \tag{1}$$
Note that for OFDM system, (1) is assumed channel input-ouput equation on ...
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How to understand MIMO zero forcing as a bank of decorrelators?
I am studying the zero forcing as a simple linear receiver for MIMO detection. according to these notes.
The zero forcing can be understood as the following two ways.
For a single stream $\mathbf{q}$,...
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Zero Forcing Equalizer in ISI channel
I'm studying on designing 9-tap zero forcing equalizer to remove ISI in the channel. I assumed that the channel response is $h[n] = [0.41, 0.815, 0.41]$ and I tried to calculate bit error rate. When I ...
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Programming a parametric equalizer - preventing clipping
I've been developing a music player for Android for many years, and I've recently started working on the implementation of a parametric equalizer.
I'm having trouble preventing a gain at one band ...
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Does zero-forcing equalizer need known channel impulse response?
I'm studying some of the basic equalizing structres and I understand how Zero-forcing works, but it seems to me that a known channel impulse response is needed. Am I right? If so, what's the point? I ...
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Parallel equalizer, working for boosts but not cuts
I am trying to replicate the behaviour of a parallel equalizer.
The approach is to use a parallel sum of bandpass filters like so:
$Response = 1 + bandpass1 * (gain1 - 1) + bandpass2 * (gain2 - 1) + ...
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How to exploit auditory masking to boost intelligibility
I am currently working on a dynamic equalizer to improve a synthesized voice's intelligibility in noisy environments.
The current implementation of my algorithm simply applies a parametric EQ to the ...
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Linear Equalizers Weights
For linear equalizers, the weights of the equalizer are set to achieve minimum error between the equalized signal and the original input signal. First, a training sequence is sent as input, and the ...
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Deciding an EQ's Center Frequencies
I am currently making a relatively simple EQ of a music app, for which we decide to have 5 bands. Other than that, we want to have a bass boost knob, which, as I view it, is just another Peak EQ ...
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The Definition of Q Factor by an Equation and How to Graph
I am currently building an EQ in an music app, and it's relatively simple:
6 bands of fixed center frequency, and a Q knob to control the Q of all bands, because we do not currently have space for ...
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FIR Audio Equalizer Crackling Noise
I've implemented a few FIR filters into a song equalizer, but there seems to be a crackling that I'm unsure how to fix.
Heres a video for reference: https://www.youtube.com/watch?v=IlzWRYpv0rk. Noise ...
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Is the Channel shortening similar to Time domain Equalizer (TEQ)
I used to read about Time domain equalizer (TEQ) in many lectures, i.e here , But in many other papers, that's called Channel shortening i.e here .
However, in the a two above links, the cost ...
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