How Do You Calculate the Average Power of a Non-Periodic Signal?

  • Context: Undergrad 
  • Thread starter Thread starter Apteronotus
  • Start date Start date
  • Tags Tags
    Power Signal
Click For Summary

Discussion Overview

The discussion revolves around the calculation of average power for a non-periodic signal, particularly focusing on random or non-correlated Gaussian signals. Participants explore different mathematical approaches and considerations relevant to this topic.

Discussion Character

  • Exploratory, Technical explanation, Debate/contested

Main Points Raised

  • One participant expresses confusion about calculating average power for non-periodic signals, contrasting it with the known method for periodic signals.
  • Another participant mentions the complexity of the mathematics involved, referencing the power spectrum and its relation to the autocorrelation of the signal.
  • A third participant suggests a specific formula for calculating average power over a time interval, questioning if this aligns with the original inquiry.
  • A fourth participant raises a question regarding the constancy of circuit impedance and proposes averaging E^2/R as a potential method for calculating power.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the method for calculating average power for non-periodic signals, with multiple approaches and questions raised without resolution.

Contextual Notes

There are assumptions regarding the nature of the signal and circuit conditions that remain unaddressed, such as the constancy of impedance and the specific characteristics of the non-periodic signal.

Apteronotus
Messages
201
Reaction score
0
Hi,

I'm wondering how do we calculate the average Power of a random (non-periodic) signal.

I know how to do it if the signal is periodic, but with a non-correlated Gaussian signal I'm a bit lost. Can anyone shed some light?

Thanks,
 
Physics news on Phys.org
It's not so simple...rather complex math...The power spectrum ( or spectral density) of a process is the Fourier transoform of its autocorrelation. I was barely able to remember enough to find that so I can't help much further.

One former text is Probability,Random Variables, and Stochastic Processes by Papoulis.
Another one that might help is Information,Transmission, Modulation and Noise, Schwartz.
These are old but may still be available in more current editions.
 
If you've measured the signal as a function of time x(t), you just need to evaluate

[tex]\frac{1}{T_2-T_1}\int_{T_1}^{T_2}|x(t)|^2\,dt[/tex]​

Is that not what you meant?
 
Is the impedance of the circuit constant? Can you average E^2/R?
 

Similar threads

Undergrad The power spectrum of Poisson noise
  • · Replies 10 ·
Replies
10
Views
2K
Undergrad Is there a list of root-power quantities? Or a rule of thumb?
  • · Replies 14 ·
Replies
14
Views
3K
Undergrad Rotating plate thrown parallel to ground
  • · Replies 2 ·
Replies
2
Views
1K
High School Feasibility of Sending a Radio Signal Detectable from a Neighboring Star
  • · Replies 5 ·
Replies
5
Views
2K
Undergrad How Do You Calculate Signal Power After Attenuation?
  • · Replies 1 ·
Replies
1
Views
3K
Undergrad Power Spectral Density - how can I get a link back to the original signal
  • · Replies 3 ·
Replies
3
Views
2K
Undergrad How Does Non-Stretchy Mat Material Affect Trampoline Performance?
  • · Replies 2 ·
Replies
2
Views
2K
Undergrad Is my calculation of the power spectrum correct?
  • · Replies 17 ·
Replies
17
Views
3K
Engineering How to find RMS, and Peak Voltages of this signal?
  • · Replies 1 ·
Replies
1
Views
2K
Undergrad Acquiring a Small Dataset of a pulsar signal
  • · Replies 3 ·
Replies
3
Views
2K