Signal Processing Stack Exchange
Signal Processing Stack Exchange

Questions tagged [phase]

A quantity representing the fraction of cycle of a periodic signal, usually represented as an angle.

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Fastest way to compute Arctan2 on an FPGA

Rip Van Winkle here -- is the fastest and least-footprint way to compute an arctan on an FPGA still to use CORDIC? Or is there a way to leverage block RAM and DSP blocks to speed and/or reduce the size of the process?
TimWescott
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Frequency dependent phase difference between signals arriving at two microphones

I wish to calculate the time difference between a signal (may or may not be periodic), arriving at the right and left channel of a stereo microphone pair kept at a distance of about 30 cm. I am doing so to localize the acoustic source. I compute the…
Samyukta Ramnath
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Best way to implement variable phase shift on FPGA?

I have an incoming digitally sampled sine wave pulse, so my FPGA has the ADC level from an I and Q channel. I want to be able to shift the phase by some arbitrary amount. What's the most efficient way to do this? The most obvious way to shift…
Zcsx706
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What does the term phase actually mean?

I am new to seismic data processing and I really have no understanding of the term 'phase'. So, could anybody give me a simple explaination of the term? Thank you
Ahmed Mohammed
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Real world use case for a battery with phase?

Referencing the following exercise by Dan: $9\rm V$ Battery with $45^\circ$ phase, I'm curious on what this would be used for in real world applications?
Aaron Hoover
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Is there a physical reason why phase should be uniformly distributed?

I was thinking a little about how signal phase might be distributed. Usually in such discussions I see people make the assumption that phase is uniformly distributed between $0$ and $2 \pi$. This only makes sense to me if its a statement about our…
user27119
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Phase of a real number

Could someone please explain in what case the phase of a real number is equal to -pi (and not pi)? I know that for positive numbers, the phase is zero. For zero, we define the phase as zero as well. And for negative numbers, the phase would be pi.…
Niousha
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Strange step response

In the figure there is represented a step response of a mechanical system. I created a step variation in the excitation of a DC generator. This lead to a step variation in the torque developed by that generator. I measured this torque with a arm…
Razvan
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The need for phase wrapping?

I understand the need for phase unwrapping and the complexity behind it. But, I'm struggling to understand why the phase information gets wrapped between $-\pi$ to $\pi$ in the first place?
JJT
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How to translate "phase" into "delay"

Suppose that a system induces a phase of -90 degree, how do I practically measure the delay in the signal coming out of the system? I think time lag would be a more useful measure than phase. Clearly these have different units, what is the…
Fraïssé
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Remove phase mis-alighnment in digital signals

Apologies for the poorly formulated question -- I've been away from DSP for a while. Let us say I have amplitude vs time data for N signals. where amplitude is -127 to 127. For each signal I have say 900 to 1100 time samples. I have a priori…
user1172468
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phase unwrapping relative to a reference

I have samples of wrapped $(-\pi,\pi)$ phase from a bandlimited signal $A(t)\cos(\pi\omega t + \phi(t)+\theta_0 )$ Frequency is constrained by very regular physics and I know a preliminary guess $\hat{\omega}$. I can also write the deterministic and…
Eli S
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Behavior at DC and Nyquist of an ideal phase shifter

In Matt L's answer he states that an ideal phase shifter with a phase shift $\theta$ has a frequency response $$ H(\omega)= \begin{cases} e^{-j\theta},&\omega>0 \\ e^{j\theta},&\omega<0 \end{cases} $$ But what about DC and Nyquist? If I want to…
DSP novice
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plotting phase transformations of a signal

I would like to find the phase variations of the signal with respect to time axes: S = sin(2*pi*100*t + pi/4) + cos(pi*500*t) + sin(2*pi*100*t + 5*pi/2);
Shaheena
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Calculating amplitude, time-shift and phase of third sinusoid as a sum of two others

My apologies in advance, I am new to this digital signal processing. Question is at the bottom I have two 4000hz sinusoids given by the following formulas: unknown frequency such that: $$x_1(t) = 24\cos(2\pi4000(t-t_{m1})) \\ x_2(t) = 28.8…
kp-a
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