# All Questions

16,488 questions
11 views

### Transfer function: from poles and zeros to polynomial coefficients

I understand how this transfer function was solved except I don't know how to get the 0.87. Any help would be appreciated.
12 views

### Scale Image by using FFT

Can we change the scale of image by using FFT? I mean, how should i do process on frequency domain of image to upscale or downscale the orginal image? The other question of mine is that how can ...
7 views

### Show and Tell: Lessons learned from the 2015 MSCOCO Image Captioning Challenge

I am looking through the source code of this paper in tensorflow.There are two phrases of training the parameters.I want to know why two phrases?
25 views

### How to uniquely identify phase difference between harmonics?

Let's say I have a multi-frequencies signal of 440Hz and 880Hz, slightly out of phase. I can take a chunk of the signal and calculate phase difference of the two frequencies with FFT bins. However, ...
14 views

### BER performance over fading channel

Suppose the channel model is a frequency-nonselective Rayleigh fading multipath channel. The received signal is expressed as r(t) = \sum_{l=1}^{L}\alpha_l s(t - \tau_l) + n(t) \end{...
9 views

### How to implement discrete extended kalman filter in matlab

I have a nonlinear system, and I need to use the extended kalman filter to estimate it. I know I need the jacobian, but once I get that, is everything else the same as the normal kalman filter? I ...
13 views

### DTFT of a time-domain signal modulated by $(-1)^n$

Given $$h[n]\leftrightarrow H(e^{j\omega})$$ How do I prove that $$\sum_{n}^{ }(-1)^nh[n]e^{\frac{j\omega n}{2}}=H(e^{j\frac{\omega+2\pi}{2}})$$ Is there some property I can apply directly? Or is ...
16 views

### Discrete signal testing for periodicity

How would one go about determining if the following discrete time signal x[n] is periodic, and if it is, determine its fundamental period? I understand that the ...
17 views

### Advances in Blind SNR estimation beyond $M_2M_4$

In Pauluzzi and Beaulieu, various SNR estimation methods are compared. Among the blind methods considered, the $M_2M_4$ estimator seemed to be unambiguously the best. However, it has been shown that ...
14 views

### Converting filterbank amplitudes to formant filters

I have a filterbank that I used to make a vocoder. It is a series of parallel bandpass filters configured to cover the spectrum in an exponential fashion. This works well and the results are exactly ...
9 views

46 views

### Is there an example of an infinite signal? [on hold]

In the real world, Is there an example of an infinite signal?
18 views

### Butterworth filters and power spectral density

I am trying to get power spectral density estimates of an hour time series, sampled at 1Hz. The only frequencies that I am interested are between 1-20 mHz. I was wondering which is the more accurate ...
21 views

### what is the best interpolation algorithm to use in Digital Up Converter (Interpolator)

As a part of my work on SDR, I want to implement a DUC in an SDR transceiver. I was looking for the DUC structure and I saw that one of most important parts is an interpolation filter used to ...
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### How to compute modulus and phase angle of images using complex morlet wavelet with fft function? [on hold]

I have a datacube of 250 thermal images. I am trying to compute the modulus and phase angle information of each images using complex morlet wavelet with fft function. Could somebody help me for this?
26 views

### How to interpret the energy value or a signal? [on hold]

I'd like to represent the frequency diagram or a sampled signal with a scale from -infinite to 0 db. Here is the way I'm processing : After applying a FFT to a finite temporal signal (= my sample) ...
3k views

### Show others how I hear myself

Sooo .. I've been thinking about this stuff. We all know that we sound different from what we hear of our own voice. It is easy to find out how others hear us by recording oneself and listen to it. ...
23 views

### PSD of a random field - mysterious power of 0.75?

I have a Gaussian covariance matrix $C$, with a known covariance kernel $k_C$. I would like to calculate the power spectral density of the Gaussian random field with covariance $C$. I would expect to ...
11 views

### What is the z-domain transfer function of variable delay?

Is it possible to obtain the transfer function of a signal that has a variable delay? For instance, I have a signal consisting of 10 samples: 0,1,1,1,1,0,0,0,0,1 If I would apply a unit delay to ...
35 views

### Random Process at a particular time instance

I was studying Random Process and I thought I understood what it was all about until I came across this example. Consider a random experiment of tossing a coin with sample space S = {H, T} The sample ...
9 views

### Blind source separation evaluation basics! [on hold]

I need a open view about blind source separation(BSS), like what actually happens when we apply BSS on a audio signal, where this signal has mainly male, female voices and background noise. Thanks in ...
29 views

### What is zero-phase filtering and forward-backward filtering?

I am pretty familiar with IIR and FIR filtering and I have implemented them in my several projects. However, recently i found something called zero phase filtering. I have tried to understand it but ...
31 views

### multiplying cosine by cosine [on hold]

a cosine wave with amplitude 1 V and frequency 3 kHz multiplied by another cosine wave with amplitude 1 V and frequency 20 kHz can anyone help with how i would calculate this?
16 views

### What are the best algorithms used for sound denoising in dsp

I thought of doing sound denoising depending on processing using wavelets, however my professor strongly stated that wavelets are not suitable for harmonics, and sounds as far as I know is mostly ...
25 views

### A time limited gaussian that has a bandlimit?

I am currently reading the paper Factored Axis-Aligned Filtering for Rendering Multiple Distribution Effects, which uses signal processing in its theory. There is one part that I do not understand. It ...
13 views

### Applying window function to reduce out of band emission for a symbol in LTE simulation?

I have to apply a window to an IFFT'ed signal (based on LTE standards, simulated for 1 symbol - 100 resource blocks - 1200 subcarriers). I have a signal which I have simulated till the IFFT. Now I ...
19 views

### Software Recommendations to Remove MP3 50 HZ Hum? [on hold]

Have a MP3 voice recording(no musical instruments) made in UK that would like to remove all 50 Hz Hum. Am interested in all suggestions concerning Windows software that can do this because am totally ...
60 views

### z-Transform Methods: Definition vs. Integration Rule

The definition of the z-transform is defined as $z = e^{sT}$ where "s" is complex frequency for continuous-time systems and "T" is the sample period. Why are rules such as the forward rectangular ...
20 views

### Barker Codes: mission? [on hold]

I learn about Digital Communication. I see this example, but do not understand about Unipolar Barker Code block: what's their mission? Why do you need to use Repeat 2x block?
20 views

### bandwith for a preamble [on hold]

I have a signal $s (t)$ with bandwidth $B=50$ Hz for example. Does the preamble have to have a bandwidth $B_{pr}=50$ Hz too?
23 views

### How can I convert binary bits into index in MATLAB [migrated]

I have a question regarding how to use the binary bits as an index in MATLAB, For example, if I'm using 4 antennas to transmit data, in each instant, one antenna or two are active to transmit the data....
22 views

### Prediction Coefficients and Power of the Residual [duplicate]

A discrete signal x is generated by the recursive process- $x_n = x_{n-1} - 0.2 x_{n-2} + w_n$ where $w_n$ is white noise with zero mean and unit variance. What is the optimum order of a linear ...
26 views

### Frequency resolution - resolution BW relation for different window functions

I am working on FFT based spectrum analyser and I am not sure how to proceed calculating the RBW. According to the document (page 20) in the link, RBW described as $k \frac{f_s}N$ where $f_s$ ...
12 views

### Signal From Neurosky Headset [on hold]

What is the best method for pre-processing a signal extracted from brain using Neurosky headset?
11 views

### Frequency selectiv MIMO channel

Under which conditions is the open loop ergodic capacity of a frequency selective channel equal to an open loop ergodic capacity of a flat fading spatially white MIMO channel?