Skip to main content
Share Your Experience: Take the 2024 Developer Survey

Questions tagged [equalizer]

The tag has no usage guidance.

Filter by
Sorted by
Tagged with
1 vote
0 answers
44 views

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 ...
Sadeq Ebrahimi's user avatar
1 vote
3 answers
168 views

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 ...
Maaz Awan's user avatar
1 vote
1 answer
96 views

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 ...
BigBrownBear00's user avatar
1 vote
1 answer
71 views

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 ...
Kunal Vaidya's user avatar
3 votes
1 answer
169 views

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 ...
Obsidian's user avatar
1 vote
1 answer
127 views

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 ...
Obsidian's user avatar
4 votes
1 answer
172 views

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 ...
Obsidian's user avatar
1 vote
0 answers
53 views

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 ...
Mahtab's user avatar
  • 11
0 votes
2 answers
204 views

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 ...
Nil Admirari's user avatar
9 votes
4 answers
670 views

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 ...
Dan Boschen's user avatar
  • 52.1k
2 votes
0 answers
25 views

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 ...
Seph Reed's user avatar
  • 305
0 votes
2 answers
210 views

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 ...
SAM's user avatar
  • 15
0 votes
0 answers
121 views

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....
Chris's user avatar
  • 1
2 votes
1 answer
141 views

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 ...
PeterO's user avatar
  • 123
0 votes
1 answer
143 views

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&...
dcs's user avatar
  • 45
-1 votes
1 answer
191 views

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 ...
Valdi's user avatar
  • 1
0 votes
1 answer
481 views

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 ...
Seph Reed's user avatar
  • 305
0 votes
1 answer
1k views

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 ...
SAM's user avatar
  • 15
0 votes
2 answers
360 views

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 ...
Clauvunate's user avatar
1 vote
1 answer
59 views

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 ...
Anil's user avatar
  • 13
1 vote
1 answer
99 views

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 ...
New_student's user avatar
0 votes
1 answer
289 views

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(|\...
thnghh's user avatar
  • 13
0 votes
0 answers
1k views

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 ...
Aren dg's user avatar
  • 21
1 vote
1 answer
170 views

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 ...
megasplash's user avatar
0 votes
2 answers
454 views

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.
dsp_guy2020's user avatar
3 votes
2 answers
1k views

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 ...
Kevin Sullivan's user avatar
0 votes
1 answer
483 views

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 ...
Fatima_Ali's user avatar
0 votes
2 answers
180 views

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 ...
Fatima_Ali's user avatar
0 votes
1 answer
485 views

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 ...
Fatima_Ali's user avatar
0 votes
0 answers
1k views

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}...
user avatar
1 vote
1 answer
143 views

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 ...
user avatar
1 vote
0 answers
255 views

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 $H(z)$...
Grigogiy Reznichenko's user avatar
1 vote
1 answer
123 views

How to use matlab toolbox for 2qam dfe equalizer?

I made Channel equalization with matlab, You can find the code below. ...
user avatar
1 vote
2 answers
590 views

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 ...
Asim Ahmed's user avatar
2 votes
1 answer
93 views

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 ...
prax1telis's user avatar
0 votes
1 answer
351 views

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 ...
Fatima_Ali's user avatar
0 votes
1 answer
200 views

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 ...
user48374's user avatar
1 vote
0 answers
203 views

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 ...
Rokai's user avatar
  • 63
0 votes
1 answer
347 views

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 $\mathbf{q}$,...
Hao xue's user avatar
2 votes
1 answer
829 views

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 ...
Jason's user avatar
  • 81
3 votes
3 answers
499 views

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 ...
Tim Malseed's user avatar
0 votes
2 answers
479 views

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 ...
researcher9's user avatar
0 votes
2 answers
104 views

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) + ...
onthefritz's user avatar
2 votes
0 answers
25 views

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 ...
user43523's user avatar
0 votes
2 answers
167 views

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 ...
Karem Adam's user avatar
1 vote
1 answer
777 views

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 ...
Nicholas's user avatar
  • 121
1 vote
0 answers
299 views

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 ...
Nicholas's user avatar
  • 121
1 vote
0 answers
208 views

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 ...
Gabriel Lins's user avatar
0 votes
1 answer
102 views

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 ...
Fatima_Ali's user avatar
-1 votes
1 answer
116 views

How to get the MLSEEqualizer work with IFFT and FFT blocks in the communication system?

Matlab MLSEE equalizer works fine with the QPSK modulated signal when the signal is propagated over the multipath channel. However, if there are IFFT and FFT blocks used at TX and RX sides, ...
tuner's user avatar
  • 635