Method of double frequency photoelectric oscillator based on phase modulation

Abstract

The invention discloses a tunable frequency doubled optoelectronic oscillator device based on phase modulation, relates to the technical field of a microwave and the technical field of optical communication, and is mainly applied to generation of a microwave local oscillator signal. The method is as shown in attached graphs. The device comprises a laser source, polarization controllers, a circulator, a polarization beam splitter, a phase modulator, an optical coupler, polarizers, a standard single mode fiber, optoelectronic detectors, a tunable bandpass filter, an electric amplifier and an electric phase shifter. The phase modulator is characterized in that modulation is carried out in a forward direction and is not carried out in a backward direction. An optical signal output from the circulator is split into two ways of signals with equal power through the optical coupler. One way is fed back to the phase modulator to form an optoelectronic oscillator, thereby obtaining a fundamental frequency signal. According to the other way, an optical carrier is inhibited by adjusting the polarization controller, thereby obtaining a frequency doubled microwave signal. Through combination of the tunable bandpass filter, the frequency doubled microwave signal with tunable frequency can be obtained. According to the optoelectronic oscillator, the frequency tuning range is relatively large, the phase noise is relatively low, and moreover, the fundamental frequency oscillator signal and the frequency doubled microwave signal can be obtained. The scheme is simple in structure and flexible in adjustment and is not influenced by bias voltage drift in a traditional strength modulation scheme.

Description

technical field

[0001] The invention relates to the technical fields of optical communication and microwave technology, and mainly relates to a phase modulation-based double-frequency optoelectronic oscillator (OEO) method in the optical communication technology. Background technique

[0002] With the continuous development of microwave photonic technology in the fields of aerospace, radar, wireless communication and electronic countermeasures, high-frequency and broadband tunable microwave signal generation technology has important application value. Compared with the traditional microwave signal generation technology, the photonics generation technology of microwave signal has the advantages of high frequency, low phase noise, tunable broadband and no electromagnetic interference, and the system structure is relatively simple, compatible with other optical systems, long-distance Good coverage and large transmission capacity.

[0003] With the development needs of military...

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