Novel single-axis optical fiber gyroscope

Abstract

The utility model discloses a novel single-axis optical fiber gyroscope, which relates to the technology of optical fiber gyroscopes and comprises an optical fiber ring, a first polarization beam splitter / combiner, a second polarization beam splitter / combiner, a Y waveguide, a coupler, a broadband light source, a PINFET detector and a signal processing circuit, the broadband light source and the PINFET detector are respectively connected to two input ports of the coupler; the output port of the coupler is connected to the input port of the Y waveguide; two output ports of the Y waveguide are respectively connected to input ports of the first polarization beam splitter / combiner and the second polarization beam splitter / combiner; and the output ports of the first polarization beam splitter / combiner and the second polarization beam splitter / combiner are respectively connected with the two ends of the optical fiber ring. According to the utility model, the problem that the size of the fiber-optic gyroscope for the seeker is limited is solved, and the accuracy and the reliability are guaranteed.

Description

TECHNICAL FIELD

[0001] The utility model relates to optical fiber gyroscope technology, concretely relates to a novel single -axis optical fiber gyroscope. BACKGROUND

[0002] As the second generation optical gyro of Sagnac effect after laser gyro, optical fiber gyro has been greatly developed since the concept of optical fiber gyro was proposed by Vail V and Shortill R W in 1976. The measurement precision of angular velocity has been from the initial low precision 15 ° / h to the high precision 0.001 ° / h order of magnitude, and has become the inertial sensor covering the most comprehensive precision range, and is widely used in military and civil fields. However, due to the need of signal demodulation, the length of the optical fiber in the fiber coil has certain limitation, to ensure the precision, the length of the optical fiber needs to reach more than 200 meters, and the result is that the volume of the fiber coil will not be small, and in the current large number of seeker projects, the volume of the fiber coil is required to be very small, and the calculation is only about 100 meters of optical fiber. Therefore, the application provides a kind of optical fiber gyro light path which can meet the need of signal demodulation and can not increase the length of the fiber coil, and the precision is not lost. SUMMARY

[0003] In view of the above-mentioned deficiencies in the prior art, the present application provides a novel single-axis optical fiber gyroscope, which can enhance the sagnac effect by changing the polarization state without changing the length of the fiber coil, thereby ensuring the required precision, effectively solving the problem of limited volume of the fiber coil for the seeker, and ensuring the precision and reliability.

[0004] In order to achieve the above-mentioned application purposes, the technical scheme adopted by the present application is as follows: a novel single-axis optical fiber gyroscope, comprising a fiber coil, a first polarization beam splitter / combiner, a second polarization beam splitter / combiner, a Y waveguide, a coupler, a wide spectrum light source, a PINFET detector and a signal processing circuit.

[0005] The wide spectrum light source and the PINFET detector are respectively connected to the two input ports of the coupler; the output port of the coupler is connected to the input port of the Y waveguide; the two output ports of the Y waveguide are respectively connected to the input ports of the first polarization beam splitter / combiner and the second polarization beam splitter / combiner; the output ports of the first polarization beam splitter / combiner and the second polarization beam splitter / combiner are respectively connected to the two ends of the fiber coil.

[0006] Further, the polarization maintaining optical fiber is used in the fiber coil, including panda type, one type and bow tie type, and the fiber coil can simultaneously transmit two beams of light beams with perpendicular vibration directions, and the two beams of light beams do not interfere with each other.

[0007] Further, the length of the fiber coil is 100 meters.

[0008] Further, the first polarization beam splitter / combiner and the second polarization beam splitter / combiner are 0° or 90° fusion spliced with the Y waveguide;

[0009] The first polarization beam splitter / combiner and the second polarization beam splitter / combiner are 0° or 90° fusion spliced with the fiber ring.

[0010] Further, the fast axis of the input port of the first polarization beam splitter / combiner is 90° fusion spliced with the slow axis of the input port of the second polarization beam splitter / combiner (3).

[0011] Further, the signal processing circuit is connected with the Y waveguide and the PINFET detector respectively.

[0012] The beneficial effects of the utility model are: compared with the conventional fiber gyroscope, the utility model discloses a kind of single-axis fiber gyroscope, in the case where the length of fiber ring is not changed, polarization beam splitter / combiner is used to realize that fiber ring transmission optical path effective use length is enlarged by one time, so scale factor can be enlarged by one time, resolution and performance are also improved close to one time, simultaneously, the application range of gyroscope is expanded, the precision and reliability of gyroscope under same length are improved.The device maturity of the utility model is high, method is simple and effective, and practicality is stronger. BRIEF DESCRIPTION OF DRAWINGS

[0013] Figure 1 It is a kind of single-axis fiber gyroscope optical path structure schematic view provided by the utility model.

[0014] Figure 2 It is a kind of signal processing circuit structure principle block diagram provided by the utility model.

[0015] Figure 3 It is a kind of single-axis fiber gyroscope polarization beam splitter / combiner structure schematic view provided by the utility model.

[0016] Figure 4 It is a kind of single-axis fiber gyroscope part optical path transmission schematic view provided by the utility model.

[0017] Wherein: 1, fiber ring;2, first polarization beam splitter / combiner;3, second polarization beam splitter / combiner;4, Y waveguide;5, coupler;6, wide spectrum light source;7, PINFET detector;8, signal processing circuit. DETAILED DESCRIPTION

[0018] The application is further described below in connection with the drawings and specific embodiments.

[0019] As Figure 1As shown, a novel single-axis fiber optic gyroscope includes an optical fiber ring 1, a first polarization splitter / combiner 2, a second polarization splitter / combiner 3, a Y-waveguide 4, a coupler 5, a broadband light source 6, a PINFET detector 7, and a signal processing circuit 8.

[0020] The broadband light source 6 and the PINFET detector 7 are respectively connected to the two input ports of the coupler 5; the output port of the coupler 5 is connected to the input port of the Y waveguide 4; the two output ports of the Y waveguide 4 are respectively connected to the input ports of the first polarization splitter / combiner 2 and the second polarization splitter / combiner 3; the output ports of the first polarization splitter / combiner 2 and the second polarization splitter / combiner 3 are respectively connected to the two ends of the fiber ring 1.

[0021] The optical fiber ring 1 uses polarization-maintaining optical fiber, including panda type, straight type and bow tie type, and the optical fiber ring 1 can transmit two beams with mutually perpendicular vibration directions at the same time, and the two beams do not interfere with each other.

[0022] The fiber optic ring 1 is 100 meters long. The fiber length of the fiber optic ring 1 is determined by the system's accuracy and the actual space requirements, and is generally set to around 100 meters.

[0023] The first polarization beam splitter / combiner 2 and the second polarization beam splitter / combiner 3 are fused to the Y waveguide 4 at 0° or 90°.

[0024] The first polarization splitter / combiner 2 and the second polarization splitter / combiner 3 are fused to the fiber ring 1 at 0° or 90°.

[0025] The fast axis of the input port of the first polarization beam splitter / combiner 2 and the slow axis of the input port of the second polarization beam splitter / combiner 3 are fused at 90°.

[0026] The signal processing circuit 8 is connected to the Y-waveguide 4 and the PINFET detector 7, respectively. Figure 2 As shown, the signal processing circuit 8 includes a preamplifier, an analog-to-digital converter, an FPGA demodulation module, a digital-to-analog converter, a communication module, and an output interface. The preamplifier is connected to the PINFET detector 7 and the analog-to-digital converter. The FPGA demodulation module is connected to the analog-to-digital converter, the digital-to-analog converter, and the communication module. The digital-to-analog converter is also connected to the Y-waveguide 4, and the communication module is also connected to the output interface.

[0027] This scheme utilizes the working principle of a polarization-maintaining beam splitter / combiner. For example... Figure 3 As shown, when the input end of the polarization beam splitter / combiner is slow-axis input (does not accept fast-axis input), the output end is slow-axis output, while when the input end is fast-axis input (does not accept slow-axis input), the output end is fast-axis output. The transmitted light of the fast and slow axes does not interfere with each other, and the reverse light follows the principle of optical path reversibility.

[0028] In one embodiment of the present application, as shown in Figure 1 and Figure 4 The light emitted by the wide-spectrum light source 6 passes through the coupler 5 into the Y waveguide 4 to produce two beams of linearly polarized light of the same characteristics, one of which enters the slow axis of the first polarization beam splitter / combiner 2 and the other of which enters the fast axis of the second polarization beam splitter / combiner 3. The light output by the first polarization beam splitter / combiner 2 then enters the slow axis of the fiber loop and is transmitted in a counterclockwise direction once before entering the slow axis of the second polarization beam splitter / combiner 3, which outputs light into the fast axis of the fiber loop and is transmitted in a clockwise direction once before entering the fast axis of the first polarization beam splitter / combiner 2. At the same time, the fast axis of the input end of the first polarization beam splitter / combiner 2 is fused at a 90° angle to the slow axis of the second polarization beam splitter / combiner 3. At this point, the fast axis of the light output by the first polarization beam splitter / combiner 2 enters the fast axis of the fiber loop 1, and the slow axis of the light output by the second polarization beam splitter / combiner 3 enters the slow axis of the fiber loop 1, completing the second transmission in the fiber loop 1. Finally, the two beams of light return to the Y waveguide 4 from the connection ends thereof, complete interference, and are transmitted to the PINFET detector 7, where the interference signal is collected and the angular rate information is resolved by the signal processing circuit 8.

[0029] Those skilled in the art will appreciate that the embodiments described herein are presented for the purpose of helping the reader understand the principles of the present application and should be understood as not limiting the scope of protection of the present application to such specific statements and embodiments. Those skilled in the art can make various other specific modifications and combinations of the present application according to the technical inspiration provided by the present application without departing from the spirit of the present application, and such modifications and combinations are still within the scope of protection of the present application.

Claims

1. A novel single-axis fiber optic gyroscope, characterized in that, It includes an optical fiber ring (1), a first polarization splitter / combiner (2), a second polarization splitter / combiner (3), a Y waveguide (4), a coupler (5), a broadband light source (6), a PINFET detector (7), and a signal processing circuit (8); The broadband light source (6) and the PINFET detector (7) are respectively connected to the two input ports of the coupler (5); the output port of the coupler (5) is connected to the input port of the Y waveguide (4); the two output ports of the Y waveguide (4) are respectively connected to the input ports of the first polarization splitter / combiner (2) and the second polarization splitter / combiner (3); the output ports of the first polarization splitter / combiner (2) and the second polarization splitter / combiner (3) are respectively connected to the two ends of the fiber ring (1).

2. The novel single-axis fiber optic gyroscope according to claim 1, characterized in that, The optical fiber ring (1) uses polarization-maintaining optical fiber, including panda type, straight type and bow tie type, and the optical fiber ring (1) can transmit two beams with mutually perpendicular vibration directions at the same time, and the two beams do not interfere with each other.

3. The novel single-axis fiber optic gyroscope according to claim 1, characterized in that, The fiber optic ring (1) is 100 meters long.

4. The novel single-axis fiber optic gyroscope according to claim 1, characterized in that, The first polarization splitter / combiner (2) and the second polarization splitter / combiner (3) are fused with the Y waveguide (4) at 0° or 90°. The first polarization splitter / combiner (2) and the second polarization splitter / combiner (3) are fused to the fiber ring (1) at 0° or 90°.

5. The novel single-axis fiber optic gyroscope according to claim 1, characterized in that, The fast axis of the input port of the first polarization splitter / combiner (2) is fused with the slow axis of the input port of the second polarization splitter / combiner (3) at 90°.

6. The novel single-axis fiber optic gyroscope according to claim 1, characterized in that, The signal processing circuit (8) is connected to the Y waveguide (4) and the PINFET detector (7), respectively.

Images