Double-pass tunable microwave photonic filter (MPF)

Abstract

The invention provides a double-pass tunable microwave photonic filter (MPF). The double-pass tunable MPF comprises a first tunable laser, a first polarization controller, a second tunable laser, a second polarization controller, a first optical coupler, a third polarization controller, a photoelectric modulator, an optical circulator, a Fabry-Perot type laser and a photoelectric detector. Two main lasers and one slave laser are adopted, a double-pass filter is realized through the principle of injection locking, and the structure is simple and compact. The two tunable lasers are adopted as two main lasers, the Fabry-Perot type laser is adopted as the slave laser, the center frequency of the MPF can be adjusted by adjusting the injection power of the two main lasers, the center frequency of the MPF also can be adjusted by adjusting the detuning frequency between the main lasers and the slave laser, and the center frequency of the MPF also can be adjusted by adjusting the bias current of the slave laser. The tunability of the MPF provided by the invention is good.

Description

Technical field [0001] The invention belongs to the technical field of microwave photonic filters, in particular to a dual-passband narrowband tunable microwave photonic filter. Background technique [0002] Filtering and frequency-selective processing of microwaves in the optical domain is one of the important research fields and has become a hot research issue in recent years. The photonic device integrated system used to filter and select the frequency of microwave signals is called microwave photonic filter (MPF). The basic method is to first convert the microwave signal into optical carrier microwave signal through electro-optical conversion (E / O), and then In the optical domain, optical fiber time delay lines, fiber gratings, optical amplifiers and other photonic devices are used to process optical microwave signals, and finally the target microwave signals are directly output through photoelectric conversion (O / E). Compared with traditional electronic circuit processing m...

AI Technical Summary

Problems solved by technology

These schemes realize the bandpass characteristics of the filter, but the tuning is relatively poor, and it will also cause the spectrum aliasing of each channel, and the reconstruction ability is relatively poor.

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