LMS TxLO noise

Thomas Tsou thomastsou at gmail.com
Fri Jul 20 22:26:36 UTC 2012


On Fri, Jul 20, 2012 at 5:33 PM, Andrey Sviyazov
<andrey.sviyazov at fairwaves.ru> wrote:
> Hi Thomas.
>
> First of all thank you very much.
>
> And of course few questions:
> 1 why you use too small input signal to the analyser? I saw -120dBc/Hz @
> 1MHz offset.

No reason. That's just how I had it setup at the time.

> 2 do you test LO with small CP current?

I went back and forth between default 0x8c and 0x93 values, which are
attached for 925 and 945 MHz.

> 3 I don't see now noise peak @ 30kHz. Do you change something?

There is a drop in the 30 kHz peak when the frequency is at 945 MHz
instead of 925.

> 4 can 4406 measuring noise plot with log freq?

Answered by Sylvain.

> 5 what type of modulation you use now? I mean 1 sps or 2?

4 sps with corrected pulse shape. The same configuration is below 2/5 on USRP1.

  Thomas
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