On Sun, Jul 22, 2012 at 3:11 PM, Srdjan Milenkovic s.milenkovic@limemicro.com wrote:
On 21/07/2012 16:28, Alexander Chemeris wrote:
Hi Srdjan,
On Sat, Jul 21, 2012 at 4:33 PM, Srdjan Milenkovic s.milenkovic@limemicro.com wrote:
Hi all,
As far as I am aware, you are currently discussing how to improve LMS6002 PLL phase noise. Below are some inputs from my side which may help.
Yes, here are some pictures of phase noise we have at UmTRX right now: http://lists.osmocom.org/pipermail/umtrx/2012-July/000030.html
It looks like they're 5-12dB higher then data I saw in your temperature measurement report. First thought is that this could be due to a clock source. Did you use your EVB board for those measurements?
Yes, we used Lime EVB, 30.72MHz TCXCO. However, using 26MHz instead of 30.72MHz TCXCO should not affect phase noise so much (5-12dB). Do you have an alternative 26MHz TCXCO with better PN? As you quite rightly mentioned, you are probably limited by TCXCO PN at the moment.
Could you please share LMS configuration you used during this test, so we could re-create it locally with the EVB we have. A full register dump of the chip would be ideal.