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12 views

cascade and summation process in frequency domain using overlap and save method

hello i'm doing signal processing like this S : FFT of input signal from microphone Exp : just gain 1/(Q*J) : include frequency component, I convert this equation to frequency domain digital filter ...
1
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1answer
25 views

BPSK based audio digital communication system

As part of my diploma thesis I'm implementing digital communication system based on audio transmission in free space (STMF401RE + analog microphone). I'm using BPSK modulation and I've implemented ...
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0answers
33 views

Sample Rate Harmonics in a Multi-Rate System

I've observed an interesting phenomena in a system I am working on that almost seems intuitive, but I don't have a good explanation of. I'm hoping someone can offer an explanation of what's happening. ...
1
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0answers
19 views

Confusion regarding STFT phase vocoder-based pitch shifting

I'm currently working on a phase vocoder implementation based on the Short-Time Fourier Transform; it's heavily based on the models described here and here. I have successfully completed the analysis ...
1
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1answer
73 views

Why is Line coding called "Line coding"?

Guys do you now why line coding also called digital base band modulation named "line coding" where does it come? and how is the name related to modulation
1
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0answers
26 views

How to use a boxcar averager in conjunction with lock-in amplifier

Suppose there exists a temporal voltage signal composed of short pulses, modulated by a sinusoidal envelope. One desires a hardware-based signal processing scheme to maximize signal to noise ratio (...
3
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0answers
48 views

Energy and Time Signals

In Signal Processing, we broadly categorize signals as either being "Energy Signals" or "Power Signals". If the total Energy for a signal is finite, we categorize it as a Energy ...
0
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1answer
19 views

How to deal with [h] coefficients which are 0 from sos-matrix

Calling scipy.signal.sosfreqz with a sos-matrix describing an ordinary butterworth bandpass returns an array of h coefficients, ...
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2answers
48 views

How can I generate a sine wave with time varying frequency that is continuous in PYTHON!

The question was asked before in C: How can I generate a sine wave with time varying frequency that is continuous? How can I resolve the following problem? I want a continuous graph. But how do I do I ...
1
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1answer
31 views

cramer lower bound, MAE, and MSE

I am quite confused, is there any relation between MSE, CRLB and MAE. Can we test the efficiency of a Maximum likelihood estimator with the MAE, or must we use CRLB? Also is it true that CRLB is MSE?
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0answers
33 views

LMS beamforming Julia Programming

I have been trying to implement a simple LMS adaptive beamforming code. Since I don't have a Matlab license I decided to use Julia since they are quite similar. In order to get a basic code working I ...
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0answers
15 views

Viterbi decoder algorithm: metrics overflow

I am working on a Viterbi decoder of a convolutional-coded messages with rate = ½ and constraint length = 7. I work with a soft-decision algorithm with 4 Bit (+7/-8). I used the MATLAB function ...
0
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0answers
21 views

Filter characteristic frequencies of one time series signal dataset and paste/add them into another

I have two categories of a time series signal dataset in the time domain - one "good" and one "bad" category. My goal is to create "fake" bad data by filtering out the ...
0
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1answer
26 views

DFT algorithm output meanning

The result of calculating the amplitude of the audio through the DFT algorithm above is It came out as below. ...
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0answers
17 views

pattern recognition with some features in time series data

I am trying to capture peaks in a time series data which has some predefined feature. Here is a snapshot of time-series data (Time series data with peaks) In this time-series I want to detect peaks ...
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0answers
19 views

Is Discrete cosine transform Translational Invariant

I am using 2D Mellin-Cepstrum to extract features, If I use log-polar transform to get rotational invariance, the rotation is transformed to translation. Can I use DCT next to get translational ...
0
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0answers
17 views

Why is there fear of interference between 5G and airline altimeter C-band?

The C-band frequency range to be used for the 5G-advanced rollout is the US is in the 3.7-3.98 GHz range. Whereas altimeters operate in the 4.2-4.4 GHz range. Is there any genuine reasons to worry ...
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0answers
12 views

How important or interesting to increase the spatial resolution of linear array for narrow band or broadband radar for SONAR or other areas?

May I request your comments, please? Consider we have a linear array (radar) to detect some targets. The system may be narrowband or broadband. Using broadband we may get better time resolution but ...
2
votes
1answer
115 views

Why is taking the inverse Fourier transform the same as taking the Fourier transform when computing the cepstrum?

Usually, the cepstrum of a signal is introduced as the result of taking the logarithm of its power spectrum, then applying the inverse Fourier transform: $$C_p = |F^{-1}\{\log(|F\{f(t)\}|^2)\}|^2$$ It ...
0
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1answer
44 views

Telecommunication with same frequencies

If signal is transmitted with same frequencies they interfers, but why can't we use the technique of encryption and decryption to stop from interfering signals with same frequencies?
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3answers
85 views

range-doppler map to range-velocity map conversion

I'm trying to implement the pulsed-doppler radar algorithm. I've went through most of the steps and generated range-doppler map where the y axis is the pulse number and the x axis is the range. I'm ...
0
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1answer
19 views

How to calculate the average power of each frequency band?

I have EEG data from 30 participants, each recording is about 3 mins, and I'm trying to calculate the average power of each frequency band. I tried using Welch's or multitaper functions, but my values ...
4
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2answers
57 views

The Effect of Spatial or Temporal Averaging on Noise Properties

I generate two noise images using MATLAB's function imnoise(). If I average the two noise images, the resultant image looks like the original noise image but only ...
3
votes
2answers
241 views

How are sounds recorded and reproduced (played back)?

Someday I have suddenly got wondered how sounds are recorded and reproduced. I searched a little bit but the information I got was composed of difficult words and contents, so I couldn't understand ...
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1answer
31 views

How whip antenna even work if they don't have two terminals?

I understand antenna should have two terminals to emit radio waves like this: But in whip antenna it has only one pointy terminal, how does it work?
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0answers
14 views

Symbol time synchronization - Rounding up average symbol time and instantaneous time

I have a symbol timing synchronizer based on the techniques discussed here. My symbol time synchronizer seems to wander too far off (and fails to lock in some cases). I have tried to limit the average ...
0
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1answer
21 views

Complexity of ZF precoding at the transmitter

If we have a modulated signal $s$ and ($m\times n$) MIMO channel $H$ where $m$ and $n$ are number of receive and transmit antenna, respectively. The ZF pre-coded signal is \begin{equation} x=Fs \end{...
1
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1answer
42 views

How fast is an histogram suppose to decay?

I am working on a software which receives streaming audio data, is expected to process that data on the fly, and then outputs the results. The module I'm working on is expected to adjust the audio ...
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0answers
76 views

Calculating complex AWGN in BPAM and QPSK

I was trying to add complex AWGN in a BPAM and a QPSK signal, manually. However I started using formulas as it is shown below (e.g. in BPAM) but the result was not the expected (also using as a ...
0
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1answer
27 views

Reconstructing function from samples

Assuming I have sampled my function with frequency above nyquist frequency, using the sampling theorem I can reconstruct my original function from the sampled values. Let's assume though that I change ...
0
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0answers
35 views

Understanding the high-pass filters in image processing

I am new to signal processing and I see that high-pass filters in image processing always have negative and positive value. In the image processing concept, why do masks have negative and positive ...
1
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0answers
13 views

How to systematically ignore image features (from a spatial light modulator)

(I am unsure if this is the best Stack Exchange site for this question. If not, please point me to the right one.) I am generating light patterns with a device called a spatial light modulator (SLM). ...
0
votes
1answer
26 views

Difference between Cramer Rao bound and mean absolute error MAE

Difference between Cramer Rao bound and mean absolute error MAE? I cannot see the difference, or where to use one and not the other. I know that Cramer and MAE are used to measure the quality of an ...
0
votes
1answer
33 views

Recognizing bees in a beehive

I would like to know if image recognition software would be sophisticated enough to recognize reach single bee in a bee hive separately (for the purpose of tracking it, and tracking, and accounting, ...
1
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0answers
25 views

Linearity of the system with Pearson correlation sliding window

I have a sampling system that consists of linear and non-linear components(analog filters, ADC, CPU, and so on). I made some HW changes and I want to verify that the linearity was preserved. My method:...
1
vote
1answer
477 views

Why is the arithmetic mean the same as the DC component of its fourier transform?

When we define $$\overline{\left|x\right|} = \frac1T\int_0^T x(t) dt$$ as the arithmetic mean of a signal we can see that it is the same as its dc component in the fourier transform. Why is this the ...
1
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1answer
61 views

What is the result of taking the real part and imaginary part of a complex signal in the frequency domain?

Suppose that $g(t)$ is a lowpass complex signal with magnitude (solid line) and phase (dashed line) To modulate $g(t)$ into a bandpass equivalent signal $f(t)$ with center frequency $f_c$, we compute ...
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0answers
16 views

Combining position estimates to enhance user localization

I have several estimated positions for an object. These positions come from several sensors. I would like to know if it is possible to combine these different positions into a single position. If yes ...
0
votes
0answers
12 views

Detecting bounded regions in JavaScript

I have an image of a crossword (i.e https://i.stack.imgur.com/qqy4X.png), and I would like to find the x,y coordinates of every valid square and the number associated with it, then I would feed it ...
0
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0answers
16 views

Filtering out motion noise from ECG

I have some ECG data that have some noise from motion in it. I also have have accelerometer data sampled at the same time. The idea is to use the accelerometer data to filter out motion noise from the ...
0
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0answers
29 views

What is reference sample in angle of arrival (AoA)?

I'm studying Bluetooth direction finding. The antenna sent I/Q data sampled start with first eight samples as reference sample and ninth sample began with sample data. Now I can calculate angle using ...
1
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0answers
34 views

Limiting value of autocorrelation of wide-sense stationary process

Let random process $X$ is wide-sense stationary process. Where could I find the source or verification of the statement that, when the limiting value of autocorrelation $\lim_{\tau\rightarrow\infty}...
0
votes
1answer
24 views

Spectral function value of a frequency above the nyqist limit

this was the question on my today's exam on signals and systems: *We have a continuous function $f(t)$. Its value of the spectral function at an angular frequency of $8000\pi\ rad/s$ is $\frac{1}{...
0
votes
1answer
31 views

Why doesn't the magnitude of Fourier Transform change when signal is shifted (i.e when a time shift is introduced)?

I understand that a time shift in the time domain produces a corresponding phase change / phase shift in the frequency domain. But I don't understand why the magnitude is unchanged (I am referring to ...
0
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0answers
17 views

Estimate a Wiener Filter with a defined inputs and system

I need to estimate a Wiener filter with two coefficients using the system h[n] = [1, 2, 3] and input x[n] = [1, 0, 2, 4]. May ...
1
vote
1answer
52 views

Identifying Instruments within a music file

Say I have a file that contains a few musical instruments, how can Identify the name of each one (ultimate goal) or at least the category they belong to, like wind instruments? For example, if I load ...
0
votes
1answer
46 views

Changing time base after applying raised cosine filter

I am generating a random sequence binary 0 and 1 to have OOK signal. ...
0
votes
1answer
29 views

Identifying an Instrument

Say I have a file that contains a single musical instrument, how can I use python code to detect which instrument is it (ultimate goal), or at least what is the category of instruments it belongs to (...
0
votes
0answers
20 views

Separating Instruments Within a Music File - python code

Is there a way to distinguish between different instruments? Let's say I have a song that contains vocals, piano, guitar, drums (etc). I would like that song to be separated into different files, each ...
1
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2answers
89 views

Is there relationship between autocorrelations Rx(2) and Rx(1)?

There is a random process, $X:\mathbb{Z}\rightarrow\mathbb{R}$ in discrete-time domain, which is wide-sense stationary with zero mean and autocorrelation function $R_X(\tau)$. a) What range of values ...

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