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AD9801 output I+jQ on DAC0

Category: Datasheet/Specs
Product Number: AD9801

Hello,

I am injecting I and Q signals stream (50M complex sinewave) from FPGA to AD9081 jesd rx.

the I signal mapped to Serdes0 -> M0, the Q signal mapped to Serdes1 -> M1 virtual converter. The jesd204B configuration is the following L=8, F=2, M=8, NP=16.

How can I see the I+JQ signal on the RF output of the DAC0? Actually I am seeing 2 sinewaves signals, one at Fnco+50M and the other one at Fnco-50M. If everything is going fine i shouldve seen only a single RF signal at either Fnco+50M or Fnco-50M depending if my Q is +90 or -90 with respect to my I data stream.

I am using 6x interpolation on the channelizer and 2x interpolation of the Main CDUC.

Where should I place the Fnco value ? on the FDUC NCO or CDUC NCO?

it seems that the I+JQ is done on the FDUC only when the Fnco of the FDUC is > 0, and then I need to put CDUC's Fnco=0 but how to do this up-shifting while having both NCOs (FDUC and CDUC) with freq>0? I suspect some Modulation Mux management but it seems not so trivial.

Best Regards,

Jawad