AnsweredAssumed Answered

Noise reduction - averaging vs IF bandwidth reduction.

Question asked by drkirkby on Oct 21, 2012
Latest reply on Oct 26, 2012 by am95405
What are the relative advantages and disadvantages of reducing noise by averaging vs reducing the IF bandwidth? 

Both slow collection speed, both reduce the noise. 

I know at least the older VNAs gave only a limited number of IF bandwidth. My 8720D has about 8 from 10 Hz to 6 KHz, if memory serves me correct.  In contrast, when it comes to averaging, there is a much wider range from 1 to 999 or something like that. 

I know narrow IF filters can produce problems if cables are long and the sweep speed is not slowed down. But I guess the same problem would arrise with averaging too. 

The VNAs I have are an HP 8720D (20 GHz lab) and N9923A (6 GHz portable). It would be nice of answers are relevant to those VNAs, though if it differs from the latest benchtop instruments, I'd be interested why. 


PS. Nice to see the forums are back running. They seem to have been down a lot lately. I'm guessing the schedulated maintainance did not go as planned.