LMS TxLO noise

Thomas Tsou thomastsou at gmail.com
Fri Jul 20 22:44:27 UTC 2012


On Fri, Jul 20, 2012 at 6:09 PM, Alexander Chemeris
<alexander.chemeris at gmail.com> wrote:
> On Fri, Jul 20, 2012 at 10:22 PM, Thomas Tsou <thomastsou at gmail.com> wrote:
>> There are still other calibration issues, but phase noise is probably still
>> a concern.
>
> You mean LO leakage and I/Q balance? Have you calibrated them? They're
> very easy to do - I could guide you with Skype if needed.

LO leakage is calibrated. I/Q balance is not. Are there steps for this
somewhere? I read 4.10 in the calibration guide, but I'm still not
sure how to proceed.

>> I also still have errors with auto calibration.
>
> Well, you haven't enabled Rx chain in LMS and thus it's reasonable
> that Rx-related calibration is failing. You should do "--lms-rx-enable
> 1" before you try to do anything with Rx.

Hmm. Similar error.

  Thomas
-------------- next part --------------
[ttsou at ovid utils (umtrx)]$ ./umtrx_lms.py --lms 1 --lms-init
[ttsou at ovid utils (umtrx)]$ ./umtrx_lms.py --lms 1 --lms-tx-enable 1
[ttsou at ovid utils (umtrx)]$ ./umtrx_lms.py --lms 1 --lms-rx-enable 1 
[ttsou at ovid utils (umtrx)]$ ./umtrx_lms.py --lms 1 --reg 0x34 --data 0x3e
[ttsou at ovid utils (umtrx)]$ ./umtrx_lms.py --lms 1 --pll-ref-clock 26e6 --lpf-bandwidth-code 0x0f --lms-auto-calibration
LPF Tuning...
DC_REGVAL = 29
LPF Bandwidth Tuning...
FREQSEL=47 VCO_X=16 NINT=196 NFRACK=7743330
VOVCO[0]=2
VOVCO[1]=2
VOVCO[2]=2
VOVCO[3]=2
VOVCO[4]=2
VOVCO[5]=2
VOVCO[6]=2
VOVCO[7]=2
VOVCO[8]=2
VOVCO[9]=2
VOVCO[10]=2
VOVCO[11]=2
VOVCO[12]=2
VOVCO[13]=2
VOVCO[14]=2
VOVCO[15]=2
VOVCO[16]=2
VOVCO[17]=2
VOVCO[18]=2
VOVCO[19]=2
VOVCO[20]=2
VOVCO[21]=2
VOVCO[22]=2
VOVCO[23]=2
VOVCO[24]=2
VOVCO[25]=2
VOVCO[26]=2
VOVCO[27]=2
VOVCO[28]=2
VOVCO[29]=2
VOVCO[30]=2
VOVCO[31]=2
VOVCO[32]=2
VOVCO[33]=2
VOVCO[34]=2
VOVCO[35]=2
VOVCO[36]=2
VOVCO[37]=2
VOVCO[38]=2
VOVCO[39]=2
VOVCO[40]=2
VOVCO[41]=2
VOVCO[42]=0
Norm
VOVCO[43]=0
VOVCO[44]=0
VOVCO[45]=0
VOVCO[46]=0
VOVCO[47]=0
VOVCO[48]=0
VOVCO[49]=0
VOVCO[50]=0
VOVCO[51]=0
VOVCO[52]=1
Low
VOVCO[53]=1
VOVCO[54]=1
VOVCO[55]=1
VOVCO[56]=1
VOVCO[57]=1
VOVCO[58]=1
VOVCO[59]=1
VOVCO[60]=1
VOVCO[61]=1
VOVCO[62]=1
VOVCO[63]=1
START=42 STOP=51 SET=46
code = f f f
RCCAL = 7
Tx LPF DC calibration...
Error: DC Offset Calibration does not converge!
Rx LPF DC calibration...
DC_REGVAL = 63
Error: DC Offset Calibration does not converge!
RxVGA2 DC calibration...
DC_REGVAL = 29
Error: DC Offset Calibration does not converge!
[ttsou at ovid utils (umtrx)]$ 



More information about the UmTRX mailing list