Loading ...
Sorry, an error occurred while loading the content.
 

I/Q phase adjustment

Expand Messages
  • edgar
    Hi Wolf, What method / algorithm is used to adjust the I/Q phase in the Spectrum Lab software? Regards, Edgar Moonah, Tasmania.
    Message 1 of 3 , Sep 25, 2013
      Hi Wolf,

      What method / algorithm is used to adjust the I/Q phase in the Spectrum Lab software?



      Regards, Edgar
      Moonah, Tasmania.
    • Graham Mcleod
      Hi Wolf, Whilst on this subject, I found that the quantization steps were too big to permit much past 70dB of unwanted sideband cancellation. Occasionally I
      Message 2 of 3 , Sep 26, 2013
        Hi Wolf,
        Whilst on this subject, I found that the quantization steps were too big to permit much past 70dB of
        unwanted sideband cancellation. Occasionally I could step on a 90 or 100dB point, but more often
        found two in the 70-odd range, stepping right over the null. Is there a way to reduce them?.
        Certainly, Amplitude error Range might be sacrificed, & trimmed in Hardware. Graham.
      • vbifyz
        Another issue with I/Q settings is that many sound cards have 1 sample delay between channels. I have some soundcards that have Left channel delayed by 1
        Message 3 of 3 , Sep 26, 2013

          Another issue with I/Q settings is that many sound cards have 1 sample delay between channels. I have some soundcards that have  Left channel delayed by 1 sample, and some that have Right channel delayed.

          I even have laptops (using IDT/Sigmatel audio chip) that have random 1/16 to 16/16 sample delay between channels, which can not be compensated by phase imbalance adjustment.


          73, Mike



          ---In spectrumlabusers@yahoogroups.com, <g8pha@...> wrote:

          Hi Wolf,
          Whilst on this subject, I found that the quantization steps were too big to permit much past 70dB of
          unwanted sideband cancellation. Occasionally I could step on a 90 or 100dB point, but more often
          found two in the 70-odd range, stepping right over the null. Is there a way to reduce them?.
          Certainly, Amplitude error Range might be sacrificed, & trimmed in Hardware. Graham.
        Your message has been successfully submitted and would be delivered to recipients shortly.