Questions tagged [equalization]
The equalization tag has no usage guidance.
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Block CMA algorithm
The Constant Modulus Algorithm is a common equalization method which adapts at every sample in an attempt to give a filter which produces a fixed power output. Divergence/convergence of the CMA ...
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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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Fractional equalizer with non-integer oversampled signal as input
I would like to know how the output sequence from a fractionally spaced equalizer, with a non-integer oversampled input signal, is generated.
For example, for $T=T_{sym}/2$, my actual code is ...
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TDE, OFDE and FDE equalizer simplest exmple in matlab
I want to implement the equalizer in matlab. I am just learning this. I want a good kick start code that can help me to learn it further. I searched a lot on Google but do not find a good reference ...
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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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Converting the equalizer coefficients from VSA at 2 sample/Symbol to 1.5 sample/Symbol
I was looking for some feedback on conversion of equalizer/filter coefficients at different sampler rate.
Problem Statement:
We have built a transmitter system whose output is at 1.5 sample/symbol (...
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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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Blind equalization with constant modulus algorithm in GNU Radio
I'm currently simulating the effect of multitap channel on BPSK as well as its remedy i.e. equalization.
The modem is expected to work with satellite TT&C transponder.
The communication channel ...
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Equalizer design for spectral gain flatness
I'm trying to design an equalizer for spectral flatness over a 100MHz signal for an LTE channel emulator. A channel emulator simply multiples channel coefficients with an external signal from a signal ...
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Constructing Contour for Star QAM Equalization
I am trying to equalize the 16 Star QAM using known blind channel algorithms such as CMA,MMA,SCA,RCA,IRCA,CXA,SCXA.I now need to contruct a new contour for equalizing the 16 Star QAM.As it is in ...
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Applications for adaptive and non adaptive histogram equalization
I have a question regarding histogram equalization and adaptive histogram equalization.
In which circumstance would it be preferable to use adaptive histogram equalization over histogram equalization ...
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Speaker equalization for white noise
I need a speaker to play broadband white noise for my scientific application. I would like to know whether my relative naive implementation is correct or not. The speakers I use have a large frequency ...
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SNR for channel after equalization
Suppose I have a channel described by $h[n]$ or $H(z)$ over which I send a simple PAM2 signal. After the channel AWGN is added.
What is the best possible SNR with equalization?
As suggested in the ...
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Instability Problem in Normalized Least Mean Squares (NLMS) Adaptive Algorithm
I have been used NLMS algorithm to equalize 4x4 MIMO signals, but the bit-error-rate (BER) after equalization is unstable with iterations. I don't know if it is the normal behavior of the adaptive ...
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Local histogram equalization
I want to learn computer vision and so I downloaded image processing slides from my university archive. I'm on histogram equalization. Learning about local histogram equalization points me out to this ...
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Multi-path equalization in SERDES system analysis
In transmitter I send the data 1 sample per bit, then received in Rx passing by ADC then FFE adaptive filter and then a slicer to return the samples in bits and calculate the BER and it works well
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Why histogram remapping is required?
Why in some applications, like biometric identification, applying histogram mapping to normal distribution after applying feature extraction (using wavelets for example) may increase the recognition ...
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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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Compensating for poor illumination across a specific image axis - possible solutions?
A friend of mine is working at an institute for nano-membranes. Currently they are using ImageJ and do a lot of manual (in my opinion inaccurate) work to process some membrane "photos" (...
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Zero padding OFDM equalization
In ZP-OFDM, The convolution is linear. it's different from CP-OFDM which is circular convolution leading to have one tap equalizer in frequency domain.
if I have a ZP-OFDM system, and we have a signal ...
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Time Reversal OFDM
I am trying to understand the Time Reversal OFDM where ,According to my opinion, the channel is reversed in time domain at receiver side and then equalized.
what I found online is something similar ...
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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}...
user47976
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On the channel estimation based on vector
I have a matrix $X$ of size .i.e $(8,8)$ with $M$ columns and $N$ rows. Suppose I took it's $iFFT$ column wise resulting matrix $x$ of size $(8,8)$ too,
$x = F^HX_{(:,m)}, $ ...... (1),
where ...
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Clip wav by PSD
I have the following two things.
sequence_1: Sound file in the wave format.
PSD_1: Some PSD (Power Spectral Density).
I want that the PSD(sequence_1) < PSD_1 for all indices.
How I think about ...
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Digital Communications block diagram question
I am new to digital communications and trying to understand the basic underlying concepts of digital comm systems. So far , studying the course , I have some questions which if anyone can answer would ...
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Satellite receiver suite
I'm in the process of implementing a general purpose baseband system for modulation schemes (Linear + CPM) commonly used satellite and deep-space TT&C as shown in the functional flow block diagram ...
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Best equalizer for a perfect CSI
Assuming a MIMO system and a perfect CSI (the channel matrix is known), what can be the best equalizer? ZF or others?
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Help me out in finding the problem in my given MATLAB code of Rectangular Contour Algorithm(RCA)
I am implementing the Rectangular Contour Algorithm (RCA) used for blind channel equalization on 32 Rectangular QAM Signal, polluted with noise and channel effects. It is described in:
Khan Q. - ...
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MMSE- Channel estimated based - DFE Equalization
For HF ionospheric channels ( frequency range 3 up to 30 MHz), I Want to make channel equalization in time domain, using MMSE criterion. I have to do it using the channel estimation.
I have some ...
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Equalization in CAR- Automotive Audio
Can someone tell me what is the purpose of CAR Equalization in audio and why before CAR Equalization ,gain adjustments are necessary ?
Also why would someone use FIR filters during CAR Equalization ...
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