Is there any improvement to the ADRV9009's NF if we reduce the BW (i.e. 10*log(BW) effect) and/or decrease the ADC sample rate (i.e. increase decimation)? There is certainly lots of NF data in the ADRV9009 datasheet, but most of it is at 200MHz BW and 245.76MSPS rate. There is some data, at lower LOs, for 50MHz BW and 61.44MSPS, like Figure 82. And that NF seems nearly the same as the wider BW and sample rate. I would have thought there would be some, though small, improvement.
Is there any other data points for Rx NF at other BW and sample rates?
From a system perspective , Since LNA is not integrated to transceiver and customer needs to use an external LNA. With a LNA with gain of 20dB and NF less than a db , the cascaded system NF will be less than 3 dB.
there will be slight improvement in transceiver NF if you reduce the bandwidth but on a cascaded system with LNA the difference will be negligible.
There are no other data other than that published in datasheet.
Understood, thank you for the reply.