I am collecting a 15Hz sine wave at 1500Hz. Therefore, every 100 points of data collected should contain a single complete sine wave. If I sample for 10 seconds, I will have 15000 points of data. If I perform an FFT on this data I will have very high frequency resolution. However, If I wanted to divide these 15000 points into 100 point sections and average them together to get a mean signal of 100 points, and performed an FFT on that, my frequency resolution would be very low. So, by averaging my data I am losing frequency resolution.
The reason I would like to get an average is because high amplitude noise is periodically injected into the sine wave. I would like to throw away the sections containing noise and only have the frequency information of the average of clean data.
I'm fairly new to DSP so I'm not quite sure how to approach this problem. Any thoughts would be greatly appreciated.