QAM (Quadrature Amplitude Modulation) optical vector signal generation and homodyne demodulation device

Abstract

The invention discloses a QAM (Quadrature Amplitude Modulation) optical vector signal generation and homodyne demodulation device, which can be applied to a coherent optical communication system. The QAM optical vector signal generation and homodyne demodulation device comprises a sending device and a receiving device, wherein the sending device comprises a laser device, a first optical splitter, a vector waveform generator, an optical modulation device, an optical phase shifter, a first polarization controller, a second polarization controller and a second optical coupler; after modulating one path of optical waves output by the first optical splitter, the optical modulation device outputs a QAM optical vector signal carrying digital base band information; the optical phase shifter performs phase shifting treatment on the other path of optical waves; and the second optical coupler couples the other path of the optical waves subjected to phase shifting and the QAM optical vector signal carrying digital base band information into optical fiber. The QAM optical vector signal generation and homodyne demodulation device enables the laser device to generate two beams of the optical waves with the same frequency and phase matching on a sending end through the utilization of coherent optical devices; after passing through a photoelectric detector on a receiving end, the optical waves are directly recovered into base band digital signals; and since no intrinsic optical source and no optical phase lock loop are required to be used, the complexity of the receiving device is lowered.

Description

technical field [0001] The invention belongs to the technical field of optical wireless communication, and more specifically relates to a QAM optical vector signal generation and homodyne demodulation device. Background technique [0002] Due to the explosive growth of people's demand for information, digital optical communication is unable to further develop the huge potential of optical fiber communication (30Tbit / s) due to the constraints of optical devices and electronic bottlenecks. Coherent optical communication has once again entered people's field of vision, and it is very likely to become the protagonist of the next generation of ultra-large capacity and ultra-long-distance optical communication. Compared with digital optical communication, coherent optical communication can use variables such as the amplitude, frequency, phase, and polarization state of the carrier to transmit information, and its information transmission efficiency is higher than that of digital o...

AI Technical Summary

Problems solved by technology

At present, the method of optical phase-locked loop is generally used to solve the problem of phase mismatch between intrinsic light and signal light.

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