pancho_hideboo
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Hi.
In Transmitter design, various issues could cause EVM(Error Vector Magnitude) degradation.
For quadrature modulator, we can consider two issues roughly.
(1) Linear issues such as carrier leakage, incomplete sideband suppression, Phase Noise and group delay ripple, etc.
(2) Nonlinear issues such as AM/AM, AM/PM, PM/PM, PM/AM.
So it is useful to relate carrier leakage, sideband suppression, phase noise, group delay ripple, P1dB, IP3 and IP5, etc. to EVM for rough estimation of EVM.
Of course, EVM is intensively dependent on modulation scheme, peak factor, power level, backoff, etc. So it is very difficult to estimate EVM. Nevertheless we still need rough estimation of EVM.
Does anyone know good relationship between EVM and primitive parameters ?
???
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