Polarization-maintaining fully-reciprocal bi-directional optical carrier microwave resonance system and angular velocity measurement method thereof

A polarization-maintaining full-reciprocity bidirectional microwave-over-fiber resonant system, comprising a bidirectional optical amplifier (1), a narrowband bidirectional optical filter (2), a first photoelectric intensity modulator (5), an optical coupler (6), a fiber sensing ring working structure (9), a second photoelectric intensity modulator (11), a first regeneration cavity delay adjustment unit (12), a first high speed photodetector (13), a first microwave filtering and amplifying unit (14), a first microwave power divider (15), a second regeneration cavity delay adjustment unit (19), a second high speed photodetector (20), a second microwave filtering and amplifying unit (21), a third microwave power divider (22), and a microwave frequency difference detection unit (23);

• wherein the bidirectional optical amplifier (1), the narrowband bidirectional optical filter (2), the first photoelectric intensity modulator (5), the optical coupler (6), the fiber sensing ring working structure (9) and the second photoelectric intensity modulator (11) are connected in sequence to form a clockwise ring resonant cavity;
• resonant light in a clockwise direction passes sequentially through the optical coupler (6), the first regeneration cavity delay adjusting unit (12), the first high speed photodetector (13), the first microwave filtering and amplifying unit (14) and the first microwave power divider (15) to be input to the first photoelectric intensity modulator (5), so as to constitute a clockwise regenerative mode-locked structure;
• an electric signal generated by the clockwise regenerative mode-locked structure is input into the microwave frequency difference detection unit (23) via the first microwave power divider (15);
• wherein the bidirectional optical amplifier (1), the second photoelectric intensity modulator (11), the fiber sensing ring working structure (9), the optical coupler (6), the first photoelectric intensity modulator (5) and the narrowband bidirectional optical filter (2) are connected in sequence to form a counterclockwise ring resonant cavity;
• resonant light in a counterclockwise direction passes through the optical coupler (6), the second regeneration cavity delay adjusting unit (19), the second high speed photodetector (20), the second microwave filtering and amplifying unit (21), the third microwave power divider (22) in sequence to be input to the second photoelectric intensity modulator (11), so as to constitute a counterclockwise regenerative mode-locked structure;
• an electric signal generated by the counterclockwise regenerative mode-locked structure is input into the microwave frequency difference detection unit (23) via the third microwave power divider (22);
• the fiber sensing ring working structure (9) comprises a polarization beam splitter (24), a fiber sensing ring (25), a first orthogonal polarization state adjustment unit (27) and a second orthogonal polarization state adjustment unit (29);
• the resonant light in the clockwise direction passes through the second orthogonal polarization state adjusting unit (29) to adjust a double-peak spectral signal of the narrowband bidirectional optical filter (2) into two paths of signals with perpendicular polarization states;
• the two paths of signals enter the fiber sensing ring (25) via the polarization beam splitter (24) and pass through the polarization beam splitter (24) and the first orthogonal polarization state adjusting unit (27) in turn to adjust the polarization states back to an initial state;
• and
• the resonant light in the counterclockwise direction sequentially passes through a first orthogonal polarization state adjustment unit (27) to adjust the double-peak spectral signal of the narrowband bidirectional optical filter (2) to two paths of signals with perpendicular polarization states;
• the two paths of signals enter the fiber sensing ring (25) via the polarization beam splitter (24) and pass through the polarization beam splitter (24) and the second orthogonal polarization state adjustment unit (29) in turn to adjust the polarization states back to the initial state.