How to define SNR of tonal component?

[cydi]

How do we define the SNR of a sinusoid, when the bandwidth of interest is of the order of a few kHz? Is it possible to measure using FFT techniques? Or for a real world signal, using a DSA?

 

[brmadhukar]

you can use a FFT. How do you plan to measure the noise?
BRM

 

[cydi]

As i have mentioned, using a spectrum analyser. There comes the confusion with bandwidth. Nois is over a specific band. Tonal for single freq....

 

[bulx]

sine power is detereministic. So if you happen to know the amplitude of the sine, you can find its power (v^2/2). Assume noise is additive. Find total power of the captured signal by squaring, summing and averaging over all samples. Subtract away the calculated sine power. Will this work?
-b

Added after 46 seconds:

sine power is detereministic. So if you happen to know the amplitude of the sine, you can find its power (v^2/2). Assume noise is additive. Find total power of the captured signal by squaring, summing and averaging over all samples. Subtract away the calculated sine power. Will this work?
-b

 

[kspalla]

I am RF guy. Measuring the NF will be limited by the NF of the instrument itself.
So it is not the right method