phase noise-->EVM?

phase noise evm

How to calculate EVM from integrated phase noise?

phase noise to evm

EVM (%) = 1.74 * RMS Phase_error (°)

calculate evm from phase noise

HI Vfone

Could you please explain the formula if possible?
Some Stuff related to this fomula?
Thanks in advance.

interpret and apply evm

Sorry for a dummy question, but what does EVM stands for??

interpret and apply evm to rf systemdesign

Hi,


Error Vector Magnitude (EVM)
The best EVM (approximately 1.0%) is achieved when all imbalances are set to zero.

Very useful document on "Interpret And Apply EVM To RF SystemDesign" is attached...

evm phase noise

additional info. on EVM

Error Vector Magnitude (EVM) is a figure of merit for modulation accuracy. Any device that exhibits AM-AM and AM-PM distortion such as power amplifier will degrade the EVM.
The DSP stages such as pulse-shaping filters and D/A conversion can have a significant effect on overall EVM

i.e the impact of phase imbalance, amplitude imbalance, and dc-offset you can see on the EVM measurement...The best EVM (approximately 1.0%) is achieved when all imbalances are set to zero...

Also
The EVM measurement is described mathematically as:

|(Vrx - Vref)|^2
EVM (%) = 100 * -----------------
|Vref|^2

where Vrx is the complex received signal (from the demodulator) and Vref is a perfect (ie undistorted) complex reference signal.

Not only the EVM-rms is important but also the spectral distribution. That is common known as phase noise. If the lower frequency components are higher some phase/frequency synchronisation methods give different perfromance results than by using flat frequency noise.

Agilent application Note is useful

Agilent PN 89400-14A

**broken link removed**

Quite good document for me.
And it helps for me doing EGPRS RF system debugging.
Thanks!!

How to measure the AM-AM and AM-PM distortion of power amplifier ?what kind of setup required

I think you need a Vector signal analyzer

My opinion is that is useless to compute EVM in other way than measuring it.

EVM = 2 * sin(phase error[degree] / 2) *100%
ex: a 0.35degree ems phase error will cause 0.61% EVM