Patent ID: 8155914

Claim:
A device for measuring a phase noise in a signal, comprising: an input port that receives an oscillation signal from an oscillator under test; a first photonic signal processing branch circuit that processes the oscillation signal to produce a first branch output signal; a second photonic signal processing branch circuit that processes the oscillation signal to produce a second branch output signal, wherein the first and second photonic signal processing branch circuits share a common optical module that includes a shared laser producing continuous wave laser light at first and second wavelengths, a shared optical modulator that modulates the laser light at the first and second wavelengths to produce modulated laser light that carries the oscillation signal, a shared optical delay that receives the modulated laser light from the shared optical modulator and a wavelength-selective optical device that separates the modulated laser light output by the shared optical delay into a first modulated laser beam at the first wavelength that is processed by the first photonic signal processing branch circuit to produce the first branch output signal and a second modulated laser beam at the second wavelength that is processed by the second photonic signal processing branch circuit to produce the second branch output signal; and circuitry that receives the first and second branch output signals to measure noise in the received oscillation signal and controls the first and second photonic signal processing branch circuits and measurements of the noise in the received oscillation signal.