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0
votes
1answer
17 views

BCI project using EEG signals

I want to make a BCI project, based on EEG signals, to control a robot using the brain's P300 wave. I have read a lot of papers, which give me a wide knowledge on how to deal with those signals, but ...
0
votes
0answers
24 views

Find similarity of sound signal

So I was working on a program to comparing the similarity between the pronunciation of a word, First I got the audio file, and I use FFT on it to get the amplitude over frequency array, then I just ...
1
vote
1answer
56 views

Why these harmonics always present?

I am using Audio Precision 2700 to test some test vectors. I have connected resistor banks as class - d power amp's load, and tap from this resistor using a XLR cable to the AP. When my power amp ...
0
votes
0answers
11 views

how could i fill missing data?

i tried a forecasting method and i want to check if it is correct or not and why? my study is about evaluating mutual funds for two kind of them it is a comparative study and i wan to use gcc index ...
0
votes
1answer
28 views

Feature vector for MFCCs

I am working on a project, for which I am finding the onset times of an audio and then extracting the MFCC coefficients for all the times. Thus if I have n onset times, I would have n feature ...
0
votes
0answers
17 views

calculate signal power for windowed sine like signal while ignoring phase shift

What is the best way to calculate the signal power of a sine like signal, recorded into a small buffer (32 samples), in such a way that phase shifts of a few samples will not have an influence on the ...
0
votes
0answers
16 views

comparing different signals

I have some noise measurements and 4 different models that can generate a similar noises using estimated parameters from the real measurements. To compare the estimated noises I calculated the PDF, ...
-1
votes
4answers
112 views
+50

Call recognition using Digital Signal Processing

We are looking for writing applications which would recognize Bird calls and Frog calls using Sound processing. EDIT: I want to identify the species of bird / frog and do not want to differentiate ...
1
vote
0answers
53 views

Audio Recognition and Learning

I'm a beginner with absolutely no experience in signal processing, but it has been a long-term goal of mine to do something that mixes music (a hobby of mine) and computer science (my "expertise"). ...
0
votes
1answer
49 views

Separating 'signal' from periodic 'noise'

I have data in which the signal we want is a few gaussian peaks superposed on a noisy background in which some of the 'noise' is periodic. Simply suppressing the associated fourier modes is effective ...
0
votes
2answers
32 views

System invertability

Can someone please explain how to determine if a system is invertible or not. The particular systems that I am looking at are: $y(t) = \cos \left( x(t) \right)$ - I believe this is non-invertable ...
0
votes
1answer
32 views

Signal magnitude area

I'm confused by the SMA. I'm reading a paper which states that "SMA is the square root of the summation of the filtered acceleration signal". So I understand that it's $sma = \sqrt{\sum{samples}}$ I ...
0
votes
1answer
23 views

Does Wav format supports writing complex values

I have a sine tone, doing some math, and finally gets an harmonically accumulated sine tone in complex numbers. I do want to preserve the phase information of imaginary part on the other end, which ...
0
votes
0answers
23 views

How to smooth out a noisy signal?

I've been waiting for an answer to my question here therfore I decided to ask the question in a different way. Could anyone please help me to smooth out the signal below!!. I've no experience of ...
0
votes
0answers
16 views

Time invariance and time variance [duplicate]

How can I write a MATLAB program that takes the given system described in terms input x(t) and output y(t) relations is input and finds out whether it is time-invariant or not?
0
votes
1answer
28 views

Usefulness of Matrix Notation for Linear Periodically Time-Variant Transformations

I am quit puzzled about a notation I found in Gardner's 1986 book titled Introduction to Random Processes. It is in the chapter on Cyclostationary Processes at section 12.4 which pertains to Linear ...
0
votes
0answers
23 views

Performance of ICA when there is low spatial separation between EEG electrodes

I have EEG data collected from a prototype Low footprint EEG device (2 in x 2 in) placed on the top of the skull. The reference channel is in the center and 8 measurement channels are spread out ...
0
votes
0answers
17 views

What are some interesting things I can do with EEG data?

I have an EEG device and would like to experiment with it a bit. Some of the data I can read from the device, in real time, are: ...
0
votes
1answer
67 views

MSK signal recoverd though FM Discriminator?

I am attempting to write a FFSK (differentially encoded MSK) modulator. I have found and implemented a demodulator that works with sample data taken from a radio of a FFSK signal. The demodulator ...
0
votes
0answers
22 views

Breakdown of Music and Esprit Algorithm

MUSIC and ESPRIT are methods that use subspace decomposition to identify signal Parameters. Subspace decomposition is achieved either by SVD or Eigen Value Decomposition. Subspace decomposition ...
-1
votes
1answer
33 views

Accumulator with decay?

I am using an accumulator in the form of X + [Y-1], X plus the unit delay of the output. Is there an accumulator that follows this form, but will fall to 0 over time, similar to a differentiator?
1
vote
1answer
34 views

Characterising a system from its input and output

I have 2 data sets sampled at regular intervals which represent the input and the output of a system. A quick analysis of the plots shows the following: There is a proportional factor between the ...
1
vote
1answer
71 views

How to learn MUSIC algorithm?

I was actually preparing for my semester project and decided to take up Frequecncy estimation.I ll directly come to the point that I want to know how should I learn MUSIC algorithm. How do I start it? ...
-1
votes
1answer
42 views

Q and I part in QAM

I have one confusion in QAM about in-phase I and quadrature Q part, i.e. do they transmit identical data or not? For e.g. if i have 11001001 as a byte to be transferred, so will 4-QAM separate it ...
2
votes
2answers
63 views

Can the order of filtering and downsampling be exchanged?

Say for example, I have a signal with maximum frequency at 600Hz, and I originally oversampled it at 2000Hz. Afterwards I was only interested in frequency less than 500Hz. I guess I could first filter ...
0
votes
3answers
122 views

Study Signal Processing

I'd Like to ask two questions : What is the difference between studying Signal processing (both Deterministic and statistical) in Department of Electrical Engineering versus Department of Mathematics ...
0
votes
0answers
27 views

Error tolerance for MUSIC (Multiple Signal Classification)

I would like to know if there is rule about how much can a matrix X-hat deviate from original matrix X $$\epsilon \le ||X -\hat{X}||_2$$ for MUSIC algorithm to still work. $$\hat{X} = X + Noise$$ I ...
1
vote
2answers
70 views

how can i get to know the frequency of a speech signal?

What is the actual meaning of frequency? what if the signal is aperiodic?? In general, we say that frequency means the repeatition of an event in unit time. But what about a speech signal? how can we ...
2
votes
0answers
57 views

Extracting the phase of a jittering sine wave using python

The background: I conducted an experiment where I rotated an object (with three-fold symmetry) many times and recorded the projection of the object. I should be able to tomographically reconstruct ...
0
votes
1answer
35 views

converting block diagrams with delays to equations

given this block diagram: can someone please clarify how to interpret the second delay (the one prior to $Y$)? to convert this block diagram into a simple equation, I interpret the diagram as: ...
-1
votes
1answer
55 views

understanding discrete-time convolution in LTI systems

I'm trying to understand the discrete-time convolution for LTIs and its graphical representation. standard explanations (like: this one) start with the idea of decomposing an input signal $x[t]$ into ...
0
votes
0answers
70 views

In a signal there is a peak, I want to find the start of the peak and the end of the peak

I want to the start time and end time for the peak shown below. The start and end are shown by the marked circles in the fig As there are number of such plots and want to know start and end time for ...
-1
votes
1answer
145 views

What are the advantages and disadvantages of the Ridgelet transform?

I used continuous wavelet transform (CWT) to analyze the behavior of a 1-D smooth signal(extracting its modal property, damping and frequency components)in my research. Now someone asked: Why the ...
0
votes
0answers
24 views

Do eigenvalues shift with change in SNR

Let $H = \frac{1}{\sqrt{2}}M + \eta$ where $M= \frac{2}{\sqrt{15}}\left( \begin{array}{cccc} 3 & 2 & 1 & 3 \\ 1 & 2 & 3 & 1 \\ 1 & 2 & 1 & 1 \end{array} \right)$ ...
1
vote
1answer
27 views

How to decode speaker gender from spoken transcript

I have 20 audio recordings (raw format) of people reciting the same ~50 word transcript. I would like to use audio signal analysis to decode speaker gender from audio recording. Intuitively, it ...
-1
votes
1answer
37 views

Describing Function for non-symmetric Saturation Model

Let's talk about a standard saturation model: with bounds $bound_{lower}$ and $bound_{upper}$. So in this example the output $y$ will be: \begin{equation} y(u) = \begin{cases} ...
1
vote
0answers
26 views

Interpolation methods for radar and acoustic imaging and potential pitfalls

A) What are the most common methods used to remap data for current generation imaging radars and acoustic sensors? B) What are some of the pitfalls in these methods? For example, in the past, at ...
1
vote
1answer
70 views

When was the time-frequency analysis invented?

It seems there are several papers from the seventies but backtracking from the references gets quickly difficult. Who calculated for the first time a time-frequency representation of a signal?
0
votes
1answer
45 views

Time shift — two interpretations

In their textbook(Example 1.1), Oppenheim and Willsky provide the following method for obtaining $g(t)=x(-t+1)$ from $x(t)$ : Replace $t$ with $-t$ in $x(t+1)$. In other words, advance the signal by 1 ...
1
vote
1answer
73 views

How to calculate Signal-To-Noise Ratio

I am doing some analysis in python working with a photodiode. The signal is more or less periodic with some phase shifting in certain areas that give rise to faster or slower periods but overall still ...
1
vote
0answers
40 views

How to replace Hadamard Product and Column wise addition with new Matrix operation?

Let $$ A= \begin{bmatrix} a_{1,1} & a_{1,2} & a_{1,3}\\ a_{2,1} & a_{2,2} & a_{2,3}\\ a_{3,1} & a_{3,2} & a_{3,3}\\ \end{bmatrix} $$ and $$ B= ...
3
votes
5answers
145 views

Why does the DFT assume the transformed signal is periodic?

In many signal processing books, it is claimed that the DFT assumes the transformed signal to be periodic (and that this is the reason why spectral leakage for example may occur). Now, if you look at ...
0
votes
1answer
33 views

Time Invariance

I cant understand this when I have a system thar compress the input as follows $$y(t)=x(2t)$$ Now to check for time invariance now I should input $x(t)$ to get $$y_1(t) = x(2t)$$ Then I should input ...
0
votes
1answer
35 views

minimum frequency in periodic components

Suppose we have the following signal model $y(t) = A_1\sin(\omega_1 t+\phi_1) + A_2\sin(\omega_2 t+\phi_2) + ... + A_p\sin(\omega_p t+\phi_p) + z(t)$ When we are sampling at sampling frequency ...
3
votes
0answers
36 views

Estimate the Discrete Fourier Series of a Signal with Missing Samples

Assuming we have a discrete signal $ { \left\{ x \left[ n \right] \right\}}_{n = 1}^{N} $. Which has a Discrete Fourier Series. Now, assume I'd like to estimate its Discrete Fourier Series ...
0
votes
1answer
64 views

Speech recognition using mfcc and neural network

I am doing the project on speech recognition.I have implemented both the mfcc features and neural network.I am a bit confused in joining the two blocks.For example i have three different words with ...
1
vote
1answer
85 views

Epoched data to a continuous signal

if we create a continuous signal from epoched data (say, EEG data with 100 epoches), what kind of problems it may cause( i am only aware of edge artifacts ) and how i can avoid them in analysis (say, ...
0
votes
1answer
53 views

Estimate digital signal

I have a device that connect with USB to my computer. This device have digital signal that I can sample it every few seconds. The signal that the device perform, is a digital signal with $X$ seconds ...
1
vote
0answers
33 views

Time delay analysis in different binary sequences

I am extracting a property of a signal which I represent with either a 0 for absent or 1 for present. This property is extracted for each data point in a time series and in the end I am left with a ...
0
votes
1answer
92 views

Lorentzian signal fit

A plot showing two S21 peaks through a resonator is given below: As you can see, the first resonance peak occurs at 4.43GHz. The fit applied to this peak is given below. $$y = A - 10 \log_{10} ...