Effective Noise Power Spectral Density

Join the discussion
Registration is free. Ask a follow-up in this thread, or start your own.
2 replies · 3K views
Kartik.Sulakh
Messages
7
Reaction score
0
How to calculate the effective noise power spectral density,
when a noise factor of 3 if given and if said to make any assumptions.

We know Effective Noise Temperature N = k.Te.B
I'm assuming it as Te = 290 K x (10 NF/10 - 1) and what about 'B'?
 
Engineering news on Phys.org
A noise factor of 3 means that the effective noise power, referred to the input, is 3 times that of the actual input noise power. I think you've got to make a lot of assumptions to make any conclusions other than that.
 
Kartik.Sulakh said:
We know Effective Noise Temperature N = k.Te.B
I'm assuming it as Te = 290 K x (10 NF/10 - 1) and what about 'B'?

"B" is bandwidth. The wider your bandwidth the more noise you'll have. For a 1 Hz bandwidth the effective noise power is -174 dBm. For a 1 kHz bandwidth it is -144 dBm, a 30 dB difference both between 1 Hz and 1000 Hz and between -174 and -144 dBm.