Questions tagged [digital]
The digital tag has no usage guidance.
152
questions
1
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1answer
78 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
19
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3answers
3k views
What sampling frequency should I use if Nyquist is not available?
I have the following homework question that confuses me:
We have an audio emitter that can emit two signals:
It either emits a sine wave at 23 kHz or it emits a sine wave at 25 kHz.
The receiver has ...
1
vote
0answers
36 views
How to recover modulation symbols？
I am using GNURadio to send and receive a limited number of modulation symbols. I have constructed the following flow chart:random source(no repeat)->chuncks to symbols(file sink1)->polyphase ...
0
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1answer
37 views
Dual functional integrated Digital Cathode Ray Oscilloscope and Digital Multimeter product
Is it feasible to design & construct a Dual functional integrated Digital Cathode Ray Oscilloscope and Digital Multimeter products in a single product?
Idea is to integrate the Digital Multimeter ...
0
votes
1answer
38 views
Phase Error Growth in Digital Mixer Signal
I am working on a code where digital mixing is to be performed for down-conversion of incoming signal. The mixer signal is created using the phase accumulation approach. However it was observed that ...
0
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0answers
18 views
Speaker Walkaround
Does anyone know what Speaker Walkaround means in context of a digital amplifier?
Also how is this test performed?
Lastly, how is it different from Load Diagnostics in Amplifiers?
1
vote
1answer
96 views
Why symbols have to be upsampling, if the symbol rate and sample rate is same what happen?
In digital modulation process, after constellation mapping and before pulse shaping, the symbols are upsampled with the number L(samples per symbol). At this moment, why symbol have to be upsampled, ...
1
vote
1answer
62 views
Balance Fader in Digital Amplifiers
What is the purpose of Balance / Fader in a digital Audio amplifier?
In a signal flow what is the most apt position to place balance and fader(for example after before a compressor unit or at the ...
0
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2answers
41 views
Centre channel derivation using correlation
I would like to know the algorithm for how centre channel is derived from rejecting left and right channel in audio upmixing process.
Can someone explain intuitively rather than hard hitting ...
0
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1answer
30 views
Is there a separate word for the time domain when working with digital signals?
Typically the phrase "time domain" implies an analog signal x(t), but I've also seen it referring to a digital signal x[n]. Is there any phrase that refers to x[n], but not x(t)?
4
votes
4answers
325 views
Why is phase range between $-\pi$ and $+\pi$ (instead of $0$ and $2\pi$)?
I wonder why the phase range in DSP applications is between $-\pi$ and $+\pi$.
For example, why is that not between $0$ and $2\pi$?
This question popped when I was reading about synchronization in ...
0
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0answers
16 views
Index frequecy offset estimation by Schmidl and Donald C. Cox
while working OFDM scheme I am unable to understand the purpose of differentially-modulated
PN sequence on the even frequencies of the second training
symbol vk. I will be thankful if someone can ...
3
votes
1answer
76 views
Wave Digital Filter Bridge-T Resonator implementation, gives expected cutoff frequency but incorrect gain and roll-off
Trying to implement the WDF in Fig 5(a) of this publication. The response of the ideal op-amp implementation is given by the black curve in Fig 7:
Here is the plot I get when trying to implement the ...
0
votes
1answer
85 views
how to convert SPL in dBA to dB
I wonder how I can convert dBA (A weighted) to dB and vice versa.
can anybody provide any kind of table or online conversion app?
thanks
following formula comes from https://en.wikipedia.org/wiki/A-...
0
votes
1answer
49 views
Does Scrambling increase speed of signal transmission overall? And is Scrambling a redundant process? [closed]
Title is a badly worded question, on which I do not have enough knowledge on the subject to answer on my own.
Anyone to help out?
0
votes
1answer
167 views
Band limited discrete signals division
If I take two analog, band limited signals $ x(t) $ and $ y(t) $ with non-zero $y(t)$ I can define the division:
$$
z(t) = \frac{x(t)}{y(t)}
$$
In general $z(t)$ may have a very wide bandwidth, also ...
0
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1answer
47 views
Find which signal was transferred in 32QAM
I've been assigned to solve a problem for 32QAM signals. The thing is, there are little to none sources in my native language to get any decent information on the topic.
The problem is (in its ...
2
votes
0answers
52 views
How can I automate the calculation for P and I coefficients of an FPGA-based digital PLL?
I am working on designing an FPGA-based PLL through an NI myRI0-1900 FPGA and LabVIEW software. I have been able to create a functioning PLL with a PI loop filter, and but I found functioning P and I ...
0
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0answers
37 views
MAP Estimation Problem for Frequency Band Occupancy Calculation
Consider designing a wireless communication system. Your communication link is not iso- lated in the environment, there are other similar devices trying to communicate in the same general frequency ...
0
votes
1answer
66 views
Decoder implementation
Im struggling to implement / build convolutional decoder .
I've done implementation of FEC encoder which it's as shown in the photo below:
So this is the encoder that I've implemented, and I want to ...
0
votes
1answer
44 views
Hw does a digital piano work?
I know someohow it combines different harmonics to synthsis note, but I don't exactly know how this happens. Does digital piano use pwm to synthesis a note?
0
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0answers
68 views
For an LTI system, the zeos and poles are defined in the z plane. How to add additional poles and zeroes so LTI system is real valued?
The question already has a zero and a pole in the complex plane. It is asking to add additional zero and pole so LTI becomes zero valued.
zeros=-1/2 + 1/2 i , poles = -1/3 -1/3 i .
What I understand ...
1
vote
1answer
159 views
Are there analog re-configurable filters?
I know that we can build a chip (or circuit) or use FPGA to have re-configurable digital filters. But how about analog filters, can we have re-configurable analog filters?
thanks
1
vote
1answer
234 views
Discrete signal vs digital signal?
Is there any difference between the two?
When we say discrete signal, does it only imply that the x-axis or time is discrete? Or it can also mean discrete amplitudes on the y-axis?
Or is the signal ...
1
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0answers
20 views
What are the applications of Non Unique Factorization Domain (Non-UFD) in signal processing? [closed]
Let $m$ be a composite, and $\mathbb{Z}_m$ is the residual ring of modular $m$. The $\mathbb{Z}_m$ is clearly a Non-UFD. What are the applications of the polynomial with coefficients defined on $\...
0
votes
1answer
44 views
Combining CDMA with differential Manchester-like encoding?
I wonder to which extend it is possible to combine a self-clocking code (like Differential Manchester encoding) with synchronous CDMA, and how it would be done?
Suppose I want to receive some bits ...
1
vote
2answers
640 views
Sampling and Reconstruction of digital signal in Matlab
I'm trying to write a program in Matlab that samples (using Nyquist theorem) and recovers signal. However, I cannot write sampling part for sum of 2 signal.
...
1
vote
2answers
266 views
Z-Transform and DFT
I have $$H(z) = \frac{\left[b_0 + b_1 \cdot z^{-1}\right]}{\left[1 + a_1z^{-1} + a_2 \cdot z^{-2}\right]}$$.
Why is it that I can calculate the spectrum between $0$ and $0.5 \cdot f_s$ by calculating ...
0
votes
1answer
200 views
How the Grayscale images are converted back to RGB?
In case of RGB to grayscale conversion we take the average of R,G,B channels and convert them to Grayscale which has songle channel. How to convert back the Grayscale to RGB ??
0
votes
1answer
56 views
Obtaining a high sample rate digital approximation to an analog filter from lower frequency measurements
Consider a set of dense, but generally irregularly-spaced frequency response measurements of some real low-pass analog filter. Denote the maximum frequency for which a frequency response measurement ...
0
votes
1answer
34 views
Two-GSMK channels demodulation: 3dB difference in BER
I am trying to demodulate individually two GSMK channels separeted by 50kHz (one channel = 25kHz).
I am working on a limited ressources hardware so I decided to make some optimization on the signal ...
0
votes
1answer
108 views
Digital beamforming and phase shift stage insertion
I have read some literatures about the different topologies of beamforming and it came to my mind a question : where is applied the phase shift for each channel depending on the type of topology/...
2
votes
1answer
81 views
phase response of an analog filter
I am trying to understand the relation between phase response of an analog filter and its influence on the quality of a signal with PSK modulation.
For example I want to design a BPF for HF ...
0
votes
1answer
41 views
inter symbol interference vs digital modulation
I am a little confused after my lecture today. My professor started off with explaining what inter symbol interference (ISI) is and he ended the lecture talking about the different types of digital ...
1
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0answers
31 views
How can we do exact simulation for digital systems? [closed]
In digital control system, there are two basic techniques for finding the best digital controller.
First, called the discrete equivalent, we find the continuous compensation and then discretize (best ...
0
votes
1answer
228 views
The selection of the amplitude of the signal, consisting of rectangular pulses, at different frequencies
I already asked a similar question, but did not receive an answer and did not find a solution, I want to make another attempt to get to the bottom of the truth.
There is a signal consisting of ...
0
votes
1answer
87 views
Carrier and timing offset
Assume my reference is 1 ppm so if my transmit frequency is 400 MHz and
symbolrate is 100 kHz.
Then, my carrier will have +/- 400 Hz offset and then my symbol will have +/-0.001 Hz offset. Similarly,...
0
votes
1answer
89 views
How to quantify phase distortion of a filter specific to a signal?
For example, a EKG input signal is filtered with a known transfer function that does not have linear phase. How do you quantify the phase distortion of the output signal given you have the input? I ...
0
votes
2answers
99 views
Length of DFT defines whether I see the harmonic or the dominant frequency
I have a number of signals that are periodic. I use an fft transformation to obtain the dominant frequency of each signal. In order to increase the frequency resolution I zero pad the signal before ...
1
vote
1answer
306 views
When calculating SNR, is noise included in signal?
Given a signal $x(t) = s(t) + n(t)$ where $s(t)$ is the desired signal voltage and $n(t)$ is the noise, should the signal to noise ratio of this signal be 20log(xrms/nrms) or 20log(srms/nrms)? i.e., ...
0
votes
1answer
397 views
How would I calculate the DC Gain for a Chebyshev Type 2 filter?
I'm currently working on an implementation of a Chebyshev Type 2 filter but the gain is all over the place when playing around with the order and ripple. I haven't found anything online but (as far as ...
0
votes
1answer
85 views
Frequency response plot and actual behavior of a digital Butterworth LPF
I have been struggling with a not-too-high (2nd) order digital Butterworth low-pass filter both in SciPy and MatLab (latest of both).
The intention is to apply this filter on signals with different ...
0
votes
1answer
78 views
What are the definitions of symbols and samples related to PCM?
What are the definitions of symbols and samples related to PCM? For example in binary encoding $\{0,1\}$ with 8 levels of quantization, is one symbol either of $ \ 0 \ or \ 1\ $? or is it the ...
6
votes
2answers
285 views
What Is the Correct Way to Apply Richarson Lucy Deconvolution to Luminance Data?
My question concerns the Richardson–Lucy deconvolution algorithm, which is described in Richardson's original paper - William Hadley Richardson - Bayesian Based Iterative Method of Image Restoration. ...
0
votes
2answers
541 views
Determine the Given system is linear or nonlinear [closed]
Does the following define a linear or nonlinear system?
$$ y(n) -4 y(n)y(2n)=x(n) $$
1
vote
1answer
137 views
Design of efficient digital interpolation filter
I came across this paper entitled "Design of Efficient Digital Interpolation Filters and Sigma-Delta Modulator for Audio DAC" where the author oversamples an input frequency, fsig = 1kHz with ratio L =...
-1
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2answers
993 views
Why is the fft magnitude spectra of sine not symmetric?
I thought that the magnitude spectra of real signals was symmetric.
When I take the absolute value of the fft of a sine wave the result is not symmetric. There seems to be a peak at the first ...
0
votes
1answer
79 views
Understanding Baud Rate
I am new to signal processing and just trying to understand what Baud rate really means.
As I understand it, the baud rate speed is really the time that the processor takes when it is ON and when it ...
0
votes
1answer
111 views
digital phase lead algorithm
I have two sine signals A and B which are simultaneously sampled at 2500 Hz using ADC. Through oscilloscope, I find that signal B lags A by about 5 degrees. I would like to digitally lead signal B to ...
1
vote
1answer
104 views
Training Fractionally Spaced Channel Estimator and Equalizer
If you are attempting least squares channel estimation with a fractionally spaced channel estimator, do you want the training sequence to also be fractionally spaced or symbol spaced? It looks like ...
