13:14 Nov 13, 2020 
English language (monolingual) [PRO] Tech/Engineering  Physics  


 
 Selected response from: Amir Akbarpour Reihani Local time: 20:56  
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The ratio of the maximum power to the medium power Explanation: The “peak to average power” level, usually expressed in dB, is the power level of the highest instantaneous power compared to the average power level. A PAR of 1, or 0 dB, means the signal is of constant power, so the peak power is equal to the average power. https://www.sciencedirect.com/topics/engineering/peaktoaverageratio#:~:text=17.11%20Peak%20to%20Average%20Ratio&text=The%20%E2%80%9Cpeak% 
 
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peaktoaverage peaktoaverage power ratio, PAPR Explanation: I'm not really sure what your doubt or question is because you haven't posed one, but I found this in two seconds: What is PAPR (Peak to average power ratio), Why it matters to Power Amplifier ? The PAPR is the relation between the maximum power of a sample in a given OFDM transmit symbol divided by the average power of that OFDM symbol. In simple terms, PAPR is the ratio of peak power to the average power of a signal. It is expressed in the units of dB. http://www.techplayon.com/paprpeakaveragepowerratiomatt... Crest factor is a parameter of a waveform, such as alternating current or sound, showing the ratio of peak values to the effective value. In other words, crest factor indicates how extreme the peaks are in a waveform. Crest factor 1 indicates no peaks, such as direct current or a square wave. Higher crest factors indicate peaks, for example sound waves tend to have high crest factors. Crest factor is the peak amplitude of the waveform divided by the RMS value of the waveform. This is equivalent to the ratio of the L∞ norm to the L2 norm of the function of the waveform:[1] C =  x p e a k  x r m s = ‖ x ‖ ∞ ‖ x ‖ 2 {\displaystyle C={\frac {x_{\mathrm {peak} }}{x_{\mathrm {rms} }}}={\frac {\x\_{\infty }}{\x\_{2}}}} {\displaystyle C={\frac {x_{\mathrm {peak} }}{x_{\mathrm {rms} }}}={\frac {\x\_{\infty }}{\x\_{2}}}} C d B = 20 log 10 (  x p e a k  x r m s ) . {\displaystyle {C}_{\mathrm {dB} }=20\log _{10}\left({x_{\mathrm {peak} } \over x_{\mathrm {rms} }}\right).} {\displaystyle {C}_{\mathrm {dB} }=20\log _{10}\left({x_{\mathrm {peak} } \over x_{\mathrm {rms} }}\right).} The peaktoaverage power ratio (PAPR) is the peak amplitude squared (giving the peak power) divided by the RMS value squared (giving the average power).[2] It is the square of the crest factor: P A P R =  x p e a k  2 x r m s 2 = C 2 {\displaystyle {\mathit {PAPR}}={\frac {{x_{\mathrm {peak} }}^{2}}{{x_{\mathrm {rms} }}^{2}}}=C^{2}} {\displaystyle {\mathit {PAPR}}={\frac {{x_{\mathrm {peak} }}^{2}}{{x_{\mathrm {rms} }}^{2}}}=C^{2}} P A P R d B = 10 log 10  x p e a k  2 x r m s 2 = C d B . {\displaystyle {\mathit {PAPR}}_{\mathrm {dB} }=10\log _{10}{\frac {{x_{\mathrm {peak} }}^{2}}{{x_{\mathrm {rms} }}^{2}}}=C_{\mathrm {dB} }.} {\displaystyle {\mathit {PAPR}}_{\mathrm {dB} }=10\log _{10}{\frac {{x_{\mathrm {peak} }}^{2}}{{x_{\mathrm {rms} }}^{2}}}=C_{\mathrm {dB} }.} When expressed in decibels, crest factor and PAPR are equivalent, due to the way decibels are calculated for power ratios vs amplitude ratios. Crest factor and PAPR are therefore dimensionless quantities. While the crest factor is defined as a positive real number, in commercial products it is also commonly stated as the ratio of two whole numbers, e.g., 2:1. The PAPR is most used in signal processing applications. As it is a power ratio, it is normally expressed in decibels (dB). The crest factor of the test signal is a fairly important issue in loudspeaker testing standards; in this context it is usually expressed in dB. https://en.wikipedia.org/wiki/Crest_factor 
 
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the highest recording (peak) compared to the average recording Explanation: For example, if you recorded the sound of a song in decibels, and there is one instance of 89 decibels, but on average the song is around 50 decibels. In this case, 89 is the peak, and 50 is the average. It is the difference between the average recording and the highest recording. Please find point 17.11 Peak to Average Ratio in the article linked below. https://www.sciencedirect.com/topics/engineering/peaktoaverageratio#:~:text=17.11%20Peak%20to%20Average%20Ratio&text=The%20%E2%80%9Cpeak% 
 
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