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-1
votes
1answer
18 views

Confusion when applying Hamming window to signal

I am writing some code which takes a signal of length $n$, and processes it in 20 ms chunks with 5 ms of overlap... So basically I have a buffer of 20 ms worth of sampled data, and I am trying to ...
1
vote
1answer
58 views

Question on Chebyshev filter

What does the output signal look like when you insert $2000 Hz$ square pulses to chebyshev filter with parameters: (Matlab syntax). I tried to do it like this but I don't understand where it goes ...
0
votes
0answers
25 views

algorithm for low frequency filter and analysis

i have a number of analog signals being monitored and then compared. My issue is that the signals are not synchronized (potentially 4-5 seconds out of phase) and my target "trouble" frequency is much ...
0
votes
0answers
24 views

Why do we use Hilbert Transform in discrete time domain?

I have few questions regarding hilbert transform, Questions are as follows: 1)What are the benifits of using hilbert transform hardware and software point of view? 2)Cannot we use any other digital ...
1
vote
0answers
33 views

Removing the mean in finding PSD

Does removing the mean value of the signal effect the estimation of power spectral density(PSD)? If it effects, how? What is the advantage we can get by removing the mean of the signal in estimating ...
0
votes
0answers
18 views

Problem in Implementing Cyclostationary Feature Detector in Matlab

I have Implemented this detector in AWGN channel in Matlab but I am getting vague result. As it performance doesn't vary with change in SNR. Its very strange result for me. I don't know what mistake I ...
1
vote
1answer
29 views

What is the use of the Welch lower bound when k > 1?

The Welch lower bound on the maximum cross-correlation (inner product) of $m$ vectors, each of $n$ elements, is given by $c_{max} = f(m, n, k)$ (eg, see Wikipedia Welch bounds). It is always assumed ...
2
votes
1answer
86 views

Regarding Bode plots; $H(s)$ and $H(j\omega)$

In circuit analysis, I understand the use of Laplace Transforms to obtain the impedance of a linear RLC circuit, ie transforming from the time domain to the frequency domain. In most texts I have seen ...
0
votes
0answers
12 views

Suppose we have the following data. How can we calculate the channel capacity and R?

A channel has a bandwith of 5MHz. If signal strength to spectral noise density S/N0 is 107 Hz, calculate the channel capacity C and R. The problem is that I can use Shannon-Hartley theorem because ...
0
votes
2answers
46 views

“Perfect waveform” for cross-correlations?

I am well versed in cross-correlations, as my masters thesis heavily relied on them for music classification and beat detection. So this question focuses more on the signals that I am running an ...
-1
votes
0answers
9 views

Segment audio signals + calculate the variances

I don't know any thing about Matlab, but I need to use it to analyze data as a part of my current project. So, could you please help me to figure how to do the following ? First, I need to segment ...
1
vote
1answer
20 views

How to apply “Substitution Method” in Difference Equations?

How to get the value of $y_p(n)$ using substitution method? What exactly do we need to substitute to get the value?
1
vote
2answers
161 views

Simple and efficient algorithm to detect frequency and phase of a sine signal

I need an algorithm to detect frequency and phase of a pure sine signal. The frequency of the input signal changes between 0 and 100 Hz. The value of the signal gets captured with a frequency of 20 ...
1
vote
1answer
34 views

range and motion in received signals by radar

I've got two signals which are consecutive received signals by a radar system. the signals values are complex (in form x+iy). I have generated a trasmitted signal using the info available. Now, I ...
0
votes
2answers
35 views

Butterworth filter in python

I'm trying to use a Butterworth filter in Python as described in this thread with these functions: ...
1
vote
1answer
50 views

why upsampling contracts the spectrum?

I'm trying to understand why Matlab function upsample causes contraction in the spectrum, like the following figure shows. Also showed in mathwork online document. enter link description here ...
0
votes
0answers
19 views

Adaptive filtering for detection of a known-frequency periodic signal

Given a very noisy signal (EEG recording), to identify which periodic component is stronger, out of $N$ (e.g. $4$) known frequencies. For the sake of completion, the application is an SSVEP-based ...
0
votes
0answers
16 views

Big sharp spikes with maximal negativity

I am wondering if anyone knows how can I detect a big sharp spikes with maximal negativity as shown in the figure below in the red box. Many thanks.
0
votes
0answers
15 views

Calculating the modulation based on the coordinates in the constellation diagram

A constellation diagram has points at the following coordinates: (2,2), (2,-2), (-2,2), ...
0
votes
1answer
55 views

Detecting a frequency swept sinusoid and its parameters?

Given a (FFT-sized) frame of data, and detection of a spectral component statistically above the noise floor in the FFT of this window, what characteristics or signal analysis could be used to ...
0
votes
2answers
91 views

Merits of “Zero-Phase” Zero Padding

I understand the reasons for zero-padding a finite signal before FFT. However, I was reading this book (http://www.dsprelated.com/dspbooks/sasp/Zero_Phase_Zero_Padding.html) where the topic is Zero ...
-2
votes
1answer
54 views

FFT on Hamming Window Function [duplicate]

I want to apply Hamming window function the Audio sample then find out its fft.. ...
0
votes
0answers
34 views

Help with IQ Balance Equations?

I have developed a spectrum scope that plots signal vs frequency starting from IQ signals. I currently do not have a way to balance the IQ signals, so am looking at various ways to do so. I have ...
0
votes
1answer
31 views

Extending a waveform

Apologies if this makes no sense or seems rather simple, I'm a Matlab newbie. Basically, I've got a .wav audio waveform which I am resampling to various different frequencies and then trimming the ...
0
votes
1answer
25 views

Bluetooth locating with RSSI and only one receiver

Is there a method to find the relative direction of a Bluetooth device to the receiver? A quick Google search on "Bluetooth positioning" returns several methods using triangulation, but I don't want ...
0
votes
1answer
20 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 ...
1
vote
1answer
96 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
70 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
44 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
20 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
33 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
5answers
127 views

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
1answer
64 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
71 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
34 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
28 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
27 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
39 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
32 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
18 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
81 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
24 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
34 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
36 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
75 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
43 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
66 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 ...