Home Forums SYSTEM DWM System

DWM System

Profile Photo
(joined April 2014)
Participant

Dear all;

I would like to ask about the effect of increasing the bandwidth of demultiplexer more than the channel spacing, for example in the attched system I use 60 GHZ DEMUX bandwidth with 50 GHz channel spacing and BER became better than BER of 40 GHz DEMUX bandwidth?

Attachments:

Responses (4):

    • #13433
      Profile Photo

      Dear all;

      I would like to ask about the effect of increasing the bandwidth of demultiplexer more than the channel spacing, for example in the attched system I use 60 GHZ DEMUX bandwidth with 50 GHz channel spacing and BER became better than BER of 40 GHz DEMUX bandwidth?

      Attachments:
    • #13440
      Profile Photo
      Damian Marek
      Participant

      Have you tried increasing the bandwidth slightly more? The fact that you are getting a superior BER might stem from your choice of filter (second order Bessel). Since the filter has a slope perhaps increasing the bandwidth to 60 GHz included more of the signal and only a little extra noise.

      Regards

    • #13449
      Profile Photo

      Hi Damian;

      I changed the filter type but BER at 60 GHz sill better than 40 GHz, is this mean that my system is not correct?

      • #13456
        Profile Photo
        Damian Marek
        Participant

        I think your system is fine, if a filter with a 60 GHz bandwidth is giving a better BER then that is reasonable. However, try increasing the filter bandwidth. Normally the BER should degrade because of increasing channel cross-talk. You could perform a Filter Bandwidth parameter sweep to find the optimum filter bandwidth.

        Cheers!

        +1
    • #13468
      Profile Photo

      Than k you Damian for your help.

Login You must be logged in to reply to this topic.