Optical transmission apparatus
AssigneeNEC Corporation
InventorRintaro Kurebayashi
Life of this patent
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Abstract
Light with a single wavelength is generated from a light source 1. Optical phase modulators 2-4 are connected to the light source 1 in series. The optical phase modulators 2-4 modulate an optical phase in accordance with an electrical signal externally inserted. The phase modulation is performed so that the phase is shifted by 0.5π with respect to a predetermined reference phase for each bit of a transmission data signal. Optical intensity modulators 5, 6 are connected to each other in series at a subsequent stage of the optical phase modulator 4. The optical intensity modulators 5, 6 modulate optical intensity in accordance with an electrical signal externally inserted.
Claims17
An optical transmission apparatus which modulates an input optical signal to output a modulated optical signal, the optical transmission apparatus comprising:
- an optical phase modulator which applies phase modulation to an input light to be outputted;
- and
- an optical intensity modulator which applies intensity modulation to the input light to be outputted in accordance with a transmission data signal,
- wherein the optical phase modulator and the optical intensity modulator are cascade-connected to each other, and the phase modulation is applied such that phase thereof is shifted by 0.5 π with respect to a predetermined reference phase for each bit of the transmission data signal.
Dependencies are inferred from the claim text.