Signal Processing Stack Exchange
Signal Processing Stack Exchange

Questions tagged [analytic-signal]

54 questions
22
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2 answers

How should I pre-process a real valued signal in order to use Kay's estimator?

I have 100,000 samples of a signal $x[n]$ that was sampled at 20kHz. The data is vibration data from a rotating machine, and contains a significant spectral component related to the speed of the machine's rotation. Because the speed of the machine…
Peter K.
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Calculate and interpret the instantaneous frequency

I'm new to the principle of calculating the instantaneous frequency, and came up with a lot of questions on it. You find them all in a bullet-point list at the end of this text. The text might be a little long, excuse me for that, but I really tried…
muuh
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1 answer

Obtain I/Q Components from a Real Signal On the Fly - Hilbert Transform or Digital Downconversion?

I'm planning to build a data acquisition system for a software-defined radio receiver. Basically, it just uses an ADC which samples an analog signal and send the signal to a processor. And then a stream of samples would be fed into a host computer…
比尔盖子
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5
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Hilbert transform: analytic signal

I want to observe how the signal's phase changes over time and I know Hilbert transform can be used here to get the analytic signal, from which I can extract the amplitude and phase. I know that to get the analytic signal $x_a(t)$ from a…
Alexey Frunze
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4
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4 answers

One-sided waveforms in both time and frequency?

Can a complex signal be one-sided (causal in time and positive only spectrum in frequency) in both domains? I understand that a function can't have finite support in both domains, but what if both domains extend to infinity in just the positive…
Dan Boschen
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I Q sampling and baseband version of analytic signal

Is it correct to say that if we have a radio signal $s(t)$ centered around the angular frequency of $\omega$ as $\omega\pm\omega_B/2$ (where $\omega_B$ is the bandwidth of the signal) and the corresponding analytic signal is $s_a(t)=s(t)+j…
axk
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calculate root mean square, ratio of power, constant false alarm, ... of a signal

I am new to Digital Signal Processing, and am reading a paper. I don't know how they can extract some features from signal, like root mean square (RMS), Constant False Alarm Rate - CFAR, Mean Value Dispersion Statistic – MVD, Ratio of Power – ROP,…
user1624637
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signals comparison metrics

Am new to signal processing and was wondering when given two signals, what are the widely used statistical analysis methods to understand the relationship between them?
Chenna V
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2
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2 answers

Prevent negative image with BPSK modulation in a complex signal

In a baseband complex signal, I need to generate a BSPK modulated signal at a given frequency. If I generate a CW at this frequency, all is good. However, when I then BPSK modulate the CW, I get a signal at both the positive and negative…
Darran
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Analytic Signal Block in Simulink Gives Reduced Amplitude for the Imaginary Part

In Simulink, I have connected a sine wave to zero-order hold and zero-order hold to analytic signal block, as in the figure below. My purpose is to transform the real signal to the corresponding analytic signal by adding complex part, in order to be…
trxrg
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Why use complex envelope to model raw measurements?

The usual answers when asking "why use complex numbers to model measurements?" is usually: (a) Because you are measuring a phenomenon like electricity and magnetism. (b) Because it is super useful for analysis- Fourier, convolutions,…
JohnRos
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Magnitude of the analytic signal

It's well known that magnitude of the analytic signal for narrowband signals gives the envelope. For example we can demodulate AM signal by abs(hilbert(s_AM)) in MATLAB. I'm looking for the exact mathematical conditions which specify when we get the…
S.H.W
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Phase change rate of human speech

I have a .wav file of human speech, sampled at 48kHz, with useful signal up to 5kHz, and almost no noise. If I do Hilbert transform in MatLab, I get the Analytic signal: $$ s_\mathrm{a}[n] = s_\mathrm{real}[n] + j \cdot s_\mathrm{hi}[n], $$ where…
K-man
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Separate Simple Signal into Exponential Components

Everyone here should be familiar with the trignonometric identity $$2 \cos(x)=e^{jx}+e^{-jx}$$ Let's say I have a real world analog signal given by the following function $$x(t)=2\cos (\omega_1 t)$$ and I only want a single exponential component,…
axsvl77
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How to "draw" the function/wave to send symbols using QAM?

Say you have the following 8QAM constellation diagram: Say, you want to send the sequence: 001 110 101 000 001 How would you draw the function/wave containing the symbols? My problem in understanding this is: I know you use amplitude and phase…
Quantm
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