Spectral Purity
The sinewave output of an ideal oscillator is a single line in the frequency spectrum. Such perfect spectral purity is not achievable in a practical oscillator. Spreading of the spectrum line caused by phase noise must be minimised in the local oscillator for a superheterodyne receiver because it defeats the aim of restricting the receiver frequency range by filters in the IF (intermediate frequency) amplifier.
Read more about this topic: Phase Noise
Famous quotes containing the words spectral and/or purity:
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—Joseph Conrad (1857–1924)
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—Henry David Thoreau (1817–1862)