Patent ID: 7460746

Claim:
A device, comprising: a light source to produce an optical beam at an optical carrier frequency; an optical modulator to modulate the optical beam in response to a control signal to produce a modulated optical beam that carries the control signal; a plurality of signal loops to respectively receive loop signals derived from portions of the modulated optical beam; a plurality of adjustable phase shifters coupled in the signal loops, respectively, to control respective phase shifts of the loop signals; a mechanism to combine the loop signals from the signal loops and to produce a feedback signal in the electrical domain; and a tunable photonic electrical filter to filter the feedback signal to produce a filtered feedback signal as the control signal received by the optical modulator, wherein the tunable photonic electrical filter comprises a second optical modulator which converts the feedback signal into an optical signal, and wherein the tunable photonic electrical filter optically filters the optical signal and tune a frequency of the filtered optical signal to tune a frequency of the control signal.