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Design >> RF Design >> Phase Noise requirement for OFDM transmitter
https://designers-guide.org/forum/YaBB.pl?num=1273060981

Message started by sandman on May 5^th, 2010, 5:03am

Title: Phase Noise requirement for OFDM transmitter
Post by sandman on May 5^th, 2010, 5:03am

Hi all,

I'm trying to perform an EVM budgeting for an OFDM transmitter. Would anyone here have a good understanding of how phase noise specifications/requirements for an LTE (OFDM) transmitter are obtained/calculated (even approximately) ?

I understand how phase noise amounts to common phase error and random phase errors but I'm not sure how the LO (PLL) phase noise requirements are calculated.

On the same thread, does anyone understand how to tie the transmitter impairments to EVM performance ? Most of the Tx impairments - IQ errors, Phase noise, Nonlinearity etc. result in a noise like 'state spreading' on the IQ constellation; so how does one budget for these impairments?

If you have strong theories or (even better) publications to share, that would be an immense help!

Thanks and cheers!

Title: Re: Phase Noise requirement for OFDM transmitter
Post by sandman on May 13^th, 2010, 8:01am

Anyone who could provide even approximative inputs?