A clock has a flat single-sideband phase noise from to

PHYSICS · Multi-part · Fermi University Physics · Electronics, Instrumentation & Communication · Feedback, operational amplifiers and analogue signal processing · Feedback, operational amplifiers and analogue signal processing

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Problem

A 500 MHz500\,\mathrm{MHz} clock has a flat single-sideband phase noise L(Δf)=−140 dBc Hz−1\mathcal{L}(\Delta f) = -140\,\mathrm{dBc\,Hz^{-1}} from Δf=1 kHz\Delta f = 1\,\mathrm{kHz} to 1 MHz1\,\mathrm{MHz}, and negligible noise outside that band. ((a)) Find the rms phase deviation ϕrms\phi_{\rm rms} over this band. ((b)) Find the rms timing jitter σt\sigma_t. ((c)) This clock is used to sample a 50 MHz50\,\mathrm{MHz} signal. Using the sampling limit SNR=1/(2πfsigσt)\mathrm{SNR} = 1/(2\pi f_{\rm sig}\sigma_t), find the signal-to-noise ratio limit in decibels.

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