what is spectral purity?
can anyone explain this or tell me from where i can get it
Thx in advance
You can search the web for the definition and examples.
Spectral purity is how clean your desired spectrum is compared to what you
want it to be.
If want to send a pure sine wave through a system (amp,mixer etc...) you would
hope to have a single (1Hz wide) spike in the Frequency domain (A Spectrum Analyzer),
and nothing else. but in the real world you will see some Harmonics and mixing products
or non-linearities of your system.
Also look up Spectral Regrowth.
Here is a photo of a signal that goes thru a ~ 10dB amp. The main signal(peak) get 10dB of gain,
but the signal to the left and right of the peak get more amplification. This is spectral regrowth
and it is an "Impurity" of the system.
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