Question about the EVM

Yes... There are several sources of EVM:

1. IQ Imbalance
2. LO Leakage
3. Phase noise
4. I/Q Amplitudes at baseband
5. Nonlinearity in the PA

there is a complexed relation between the a3 (third order nonlinearity) in the PA to the EVM which I believe can be found in the literature.

Jim

Hello Sixth & Jim,

Yes...
Find attached are the 3 excellent documents which completely decribes from Scratch EVM, for PA for OFDM, WLAN etc...
Very useful document on "Interpret And Apply EVM To RF SystemDesign"

"Don't Let Linearity Squeeze Your WLAN performance" and

"Effect of Power Amplifier Impairments in Designing OFDM Based Wireless Communication Systems"
are attached...


---manju---