Matched filter is obtained by correlating a known signal, or template, with an unknown signal to detect the presence of the template in the unknown signal.

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Matched filters

Working on my communication class right now, and I'm having a bit of a problem with the matched filters. As I see it the matched filters "eliminate" some of the noise. We project the received signal ...
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Create Matched Filter Reference Signal when Scaling Unknown

I am working on a problem which raised what should be a simple question, but I'm stuck on it. The objective is to detect a shifted and scaled version of a known signal in the presence of Additive ...
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How does a matched filter know about input signal beforehand?

I know that a matched filter at time t0 is just the input signal reversed in time about that time. But how does the filter know about input signal. Received signal is transmitted signal plus the noise ...
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How matlab calculates matched filter gain

Here is a bunch of code from Matlab documentation : Designing a Basic Monostatic Pulse Radar: ...
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MACE filters for face recognition

I am trying to implement this paper in Matlab: http://scourge.fr/mathdesc/documents/facerecog/mace.pdf Although I have followed all the steps in the paper, I am not getting any peak values as in the ...
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Is it possible to open up this particular convolution equation?

I have three vectors, $x[n]$, $w[n]$, and $z[n]$. I need to compute: $y[n] = z[n] * \Big(x[n] \cdot w[n] \Big)$. This is easy to do. However, is there a way I can do this by 'opening' up the ...
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BER calculation in DS-UWB system

I need to calculate BER (bit error rate) for a system using spreading spectrum DS over ultra wideband (UWB). Modulation is bpsk. The spreading sequence lengths are not equal for all users. Receiver is ...
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Understanding matched filter

I have a question about matched filtering. Does the matched filter maximise the SNR at the moment of decision only? As far as I understand, if you put, say, NRZ through a matched filter, the SNR ...
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Image Matching on iOS

Was recommended to migrate this question from SO. I am building an iOS app that, as a key feature, incorporates image matching. The problem is the images I need to recognize are small orienteering ...
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Match Filter in Time-Frequency domain instead of just Time domain. Redundant, or better?

Assume you have a signal, and within it, some pulses are present. A pulse is a simple tone. You know the pulses' duration, and shape. (Let us assume that a pulse is made of a couple of cycles, and ...
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How do you calculate the gain of a matched filter?

I know that you can calculate the gain of a low-pass filter by summing the filter coefficients. I don't know how to calculate the gain of an arbitrary matched filter. For instance, I have created a ...
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Discrete-time model of 2-user CDMA system, recovered information at receiver using polarity detection?

I have discrete-time model of 2-user CDMA system with: $b_1=-1, b_2=+1, \alpha_1, \alpha_2, s_1, s_2$ and $n$ white noise. What are the recovered infromation bits for user 1 and user 2 respectively ...
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Optimum matched filter without ISI

Given a filter used to shape the digital signal, $p(x)$, and given that we do not want the filter combination to cause any ISI, what "matched" filter, $q(x)$ will maximise the SNR? Matched filters ...