Troubleshooting The example Mixer Project - RF Cafe Forums

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dstraight

Post subject: Troubleshooting The example Mixer Project Posted: Thu Oct 06, 2005 4:22 pm

Captain

Joined: Sun May 09, 2004 1:23 am

Posts: 10

Location: Morgan Hill, CA (Silicon Valley, Bay Area)

Okay, I decided to drive home for lunch so that I could gather a few screen captures (I am lucky in that I live and work in the same town).

Below is a schematic of the example design (SweptRF.dsn) from the Mixers_prj project and below this we see graphs of the resultant simulation.

As stated in my last post I've only added one net at the LO port of the mixer and named it "VLO" then I produced a plot of the VLO and Vrf (verses swept RF frequency, Frf) as shown in the graphs below. The third screen capture shows the most detail.

As can be seen from these graphs the project appears to be running correctly, but when I try to look at the signals going into the mixer I do not see anything that would make sense. In the graphs RF power should say -20dBm at 1GHz and LO power should read -5dBm at 1GHz-70MHz= 930MHz, but as the two graphs show LO power is below -50dBm and RF power is below -60dBm.

Perhaps the graphs that I have drawn take frequency samples that do not sample exactly at 1GHz and 930MHz thus explaining absence of power. I do not know.

Top

dstraight

Post subject: Posted: Thu Oct 06, 2005 4:25 pm

Captain

Joined: Sun May 09, 2004 1:23 am

Posts: 10

Location: Morgan Hill, CA (Silicon Valley, Bay Area)

Opps! I screwed up. This posting was supposed to go under "ADS using Harmonic Balance with mixers," but I've created a new post by mistake.

If anyone can move this message for me (or delete it so that I can repost in the correct area) I'd appreciate it.

Posted  11/12/2012