摘要:
An RF signal transceiver comprising a mode-locked laser to output an optical signal having a plurality of phase-locked modes, an optical splitter to power split the optical signal into a transmitter optical signal and a receiver optical signal; a transmitter apparatus to receive the transmitter optical signal and comprising an optical filter to select two of the modes, an optical modulator to modulate a part of the transmitter optical signal to form at least one phase modulated optical signal, and a photodetector to heterodyne the phase modulated optical signal with one of the modes without a corresponding phase modulation to form an RF signal for transmission; and a receiver apparatus arranged to receive an RF signal and the receiver optical signal and comprising an optical modulator to modulate the receiver optical signal with the received RF signal; and an optical to electrical signal conversion apparatus to convert the modulated receiver optical signal into a corresponding electrical signal.
摘要:
An apparatus and method for generating a train of optical pulses. The apparatus comprises an optical resonant cavity (1) for confining an optical signal in the cavity to a number of modes, a modulator (3), and a control signal generator (101). The modulator comprises an interferometer arranged to cause interference of the optical signal with itself to produce an output and controllable material, such as an electro-optic crystal, arranged in a path of the optical signal, an optical property of the controllable material dependent on a control signal (3b) applied to the controllable material such that changes in the optical property alter optical signals travelling that path to affect the interference of the optical signals, and therefore the output of the modulator. The control signal generator is arranged to generate the control signal, wherein the control magnitude is an oscillating waveform arranged to cause transmission of the optical signal through the modulator to generate pulses having a pulse width shorter than a pulse width of pulses that would be generated using a sinusoidal waveform of the same frequency.
摘要:
An optical label extractor (10) comprising a non-linear optical element (12), a pump source (14) and optical filter apparatus (16). Said non-linear optical element (12) is arranged to receive optical data packets (18) at data signal wavelengths. Each said data packet comprises at least one data bit and at least one label bit. Said pump source (14) is arranged to pump said non-linear optical element such that any non-zero label bit experiences a non-linear optical effect on propagation through said non-linear optical element and an output label bit (20) comprising a respective further wavelength is thereby generated. Said optical filter apparatus (16) is arranged to receive any said output label bit from said non-linear optical element and being further arranged to prevent transmission of a part of said output label at said respective data signal wavelength and to transmit a part of said output label bit at said respective further wavelength.