Anti-noise linear modulation system

Abstract

The utility model provides an anti-noise linear modulation system, which comprises a rack and a fiber bragg grating for filtering, and is characterized in that at least one support frame is arranged on the rack, and an upper threaded rod is arranged above the support frame; the device further comprises an adjusting rod, threads are arranged at the upper end of the adjusting rod, and the adjusting rod and the threaded rod are both in threaded connection with the two-way threaded sleeve. The device further comprises a first lever installed at the lower end of the supporting frame through a hinged support, one end of the first lever is connected to the lower end of the adjusting rod, the other end of the first lever is provided with a threaded pull rod, the threaded pull rod is spirally connected to the rack, and the fiber bragg grating is fixed to the adjusting rod and deforms along with the adjusting rod. According to the scheme, the structure is simple, linear adjustment of four kinds of precision can be carried out on the filter in optical fiber communication with three kinds of precision, and the purpose of reducing system noise is achieved.

Description

Technical Field

[0001] This application relates to the field of communication system equipment, and more specifically to a noise-resistant linear modulation system. Background Technology

[0002] For optical signal filtering, narrowband filtering technology is a key means to improve the signal-to-noise ratio of a system. The main methods for filtering signal light in communication systems include interference filtering, birefringence beam splitting, and atomic resonance. Fiber Bragg gratings (FBGs) are small, inexpensive, and simple to manufacture, making them suitable for mass production. Furthermore, because their Bragg echo wavelength half-width can be adjusted through grating etching, the required bandpass filtering width can be selected. Using FBGs to filter optical signals can achieve precise and tunable bandpass filtering effects.

[0003] The working principle of FBG is that when broadband light is incident from an optical fiber onto the FBG, the fiber grating structure is equivalent to a light-transmitting multilayer film structure. This results in reflection and projection at the interfaces of each film layer. The wavelength of the reflected light has a functional relationship with the film thickness, meaning that the light waves constituting the Bragg condition undergo iterative reflection. (See attached image) Figure 5 As shown, the relationship between the incident light signal and the transmitted light signal is illustrated. Simply put, there is a certain functional relationship between the spacing of the gratings inside the FBG and the filtering capability. The spacing of the gratings is affected by the deformation of its packaging jacket along its length and the thermal expansion and contraction of the ambient temperature. When the deformation is large, it affects its filtering performance and generates communication noise. Utility Model Content

[0004] (a) Technical issues

[0005] In view of the above-mentioned existing technology, there is an urgent need to design a device that can perform coarse and fine adjustments on fiber Bragg gratings in order to reduce the noise generated by fiber Bragg gratings.

[0006] (II) Technical Solution

[0007] To address the aforementioned technical problems, this application proposes a noise-resistant linear modulation system, comprising a frame and a fiber Bragg grating for filtering. The system is characterized by: at least one support frame mounted on the frame, with a threaded rod positioned above the support frame; an adjusting rod with a threaded upper end, both the adjusting rod and the threaded rod being threadedly connected to a bidirectional threaded sleeve; and a first lever mounted on the lower end of the support frame via a hinge support, one end of the first lever connected to the lower end of the adjusting rod, and the other end having a threaded pull rod helically connected to the frame. The fiber Bragg grating is fixed to the adjusting rod and deforms with the adjusting rod.

[0008] Furthermore, the ratio of the two arms of the first lever is 1:3.

[0009] Furthermore, the frame is also provided with a second support frame, and includes a second lever installed at the lower end of the support frame via a hinge support. One end of the second lever is connected to the lower end of the adjusting rod, and the other end is provided with a threaded pull rod, which is helically connected to the frame.

[0010] Furthermore, the ratio of the two arms of the second lever is 1:2.

[0011] Furthermore, the frame is also provided with a third support frame, and includes a third lever installed at the lower end of the support frame via a hinge support. One end of the third lever is connected to the lower end of the adjusting rod, and the other end is provided with a threaded pull rod, which is helically connected to the frame.

[0012] Furthermore, the ratio of the two arms of the third lever is 1:5.

[0013] Furthermore, multiple support legs are provided under the frame, and the support legs have a cushioning function.

[0014] (III) Beneficial Effects

[0015] This solution has a simple structure, but it can linearly adjust the filter in optical fiber communication with four different levels of precision, thereby reducing system noise. Attached Figure Description

[0016] Figure 1 This is a three-dimensional view of the structure according to this application;

[0017] Figure 2 This is a top view of this application;

[0018] Figure 3 A schematic diagram of this application viewed from another perspective;

[0019] Figure 4 This is a side view of this application;

[0020] Figure 5 This is a schematic diagram of the principle of a fiber Bragg grating.

[0021] Note that the two ends of the Bragg grating FBG in the figure are connected to optical fibers, which are not shown in the figure.

[0022] Attached Figure

[0023] 1. Rack

[0024] 2. Support frame

[0025] 3. Threaded rod

[0026] 4. Adjusting rod

[0027] 5. Double-ended threaded sleeve

[0028] 6. First Lever

[0029] 7. Hinge support

[0030] 8. Threaded tie rod

[0031] 9. Handle

[0032] 10. Second Lever

[0033] 11. The Third Lever

[0034] 12. Fiber Bragg grating

[0035] 13. Support legs Detailed Implementation

[0036] The present invention will be further described below with reference to the embodiments.

[0037] like Figure 1 As shown, a noise-resistant linear modulation system according to this application includes a frame 1 and a fiber Bragg grating for filtering. The system is characterized by: at least one support frame 2 being provided on the frame, and an upper threaded rod 3 being provided above the support frame; it also includes an adjusting rod 4, the upper end of which is threaded, and both the adjusting rod 4 and the threaded rod 3 are threadedly connected to a bidirectional threaded sleeve 5; it further includes a first lever 6 mounted on the lower end of the support frame via a hinge support 7, one end of which is connected to the lower end of the adjusting rod 4, and the other end is provided with a threaded pull rod 8, which is helically connected to the frame. The fiber Bragg grating is fixed to the adjusting rod 4 and deforms with the adjusting rod.

[0038] The working principle of this application is as follows: the FBG is connected to the optical fiber communication line, and its noise is analyzed using a spectrum analyzer. Depending on the noise level, there are two adjustment methods: 1) Tightening the bidirectional screw sleeve 5 pulls the adjusting rod 4 upwards, causing a slight deformation that affects the spacing of the grating in the FBG, thus changing its filtering performance. The adjustment direction for noise reduction can be observed on the spectrum analyzer display.

[0039] Because the grating is very precise, the deformation caused by threaded adjustment depends on the pitch and is relatively coarse, often failing to achieve the desired adjustment effect. Therefore, this device also incorporates a second adjustment method: applying a downward or upward force to the adjusting rod via a threaded pull rod (connected to the first lever 6, but without affecting its helical motion; for example, it could be connected via a ball joint). Since it is connected to the lower end of the adjusting rod through a lever structure of a hinged support, only a portion of its helical stroke contributes to the deformation of the adjusting rod, making it a more precise adjustment method.

[0040] Furthermore, the ratio of the two arms of the first lever is 1:3.

[0041] Furthermore, the frame is also provided with a second support frame, and includes a second lever 10 installed at the lower end of the support frame via a hinge support. One end of the second lever is connected to the lower end of the adjusting rod 4, and the other end is provided with a threaded pull rod, which is helically connected to the frame.

[0042] Furthermore, the ratio of the two arms of the second lever is 1:2.

[0043] Furthermore, the frame is also provided with a third support frame, and includes a third lever 11 installed at the lower end of the support frame via a hinge support. One end of the third lever is connected to the lower end of the adjusting rod 4, and the other end is provided with a threaded pull rod, which is helically connected to the frame.

[0044] Furthermore, the ratio of the two arms of the third lever is 1:5.

[0045] Furthermore, multiple support legs are provided under the frame, and the support legs have a cushioning function.

[0046] In this design, different levers transmit deformation at different ratios, thus providing varying adjustment precisions, and are easily adjustable together with bidirectional screw sleeves. Furthermore, analyzing the degrees of freedom of the moving parts of the device from the perspective of device degrees of freedom is not easy, but it is important to note that all adjustments in the entire device are designed to produce minimal deformation. As long as the tension or pressure induced by the deformation is applied to the adjusting rod, causing it to deform as well, it can perform its adjustment function normally without becoming immobile. This, combined with a spectrometer, reduces fiber optic noise to an ideal level. Because the deformation of the adjusting rod is linear, it is used in linear optical communication modulation systems.

[0047] The above description provides a detailed account of one embodiment of the present invention. However, this description is merely a preferred embodiment and should not be construed as limiting the scope of the present invention. All equivalent variations and improvements made within the scope of the claims of the present invention should still fall within the patent coverage of the present invention.

Claims

1. A noise-immune linear modulation system comprising a frame and a fiber Bragg grating for filtering, characterized in that: The rack is provided with at least one supporting frame, and an upper threaded rod is arranged above the supporting frame; further comprising an adjusting rod, the upper end of the adjusting rod is provided with a thread, and the adjusting rod and the threaded rod are threadedly connected with a bidirectional screw sleeve; further comprising a first lever installed at the lower end of the supporting frame through a hinge support, one end of the first lever is connected to the lower end of the adjusting rod, the other end is provided with a threaded pull rod, the threaded pull rod is screw-connected on the rack, and a fiber Bragg grating is fixed on the adjusting rod and deforms along with the adjusting rod.

2. A noise- immune linear modulation system according to claim 1, characterized in that: The ratio of the two arms of the first lever is 1:

3.

3. A noise- immune linear modulation system according to claim 2, characterized in that: The rack is further provided with a second supporting frame, and further comprising a second lever installed at the lower end of the supporting frame through a hinge support, one end of the second lever is connected to the lower end of the adjusting rod, and the other end is provided with a threaded pull rod, which is screw-connected on the rack.

4. A noise- immune linear modulation system according to claim 3, characterized in that: The ratio of the two arms of the second lever is 1:

2.

5. A noise- immune linear modulation system according to claim 4, characterized in that: The rack is further provided with a third supporting frame, and further comprising a third lever installed at the lower end of the supporting frame through a hinge support, one end of the third lever is connected to the lower end of the adjusting rod, and the other end is provided with a threaded pull rod, which is screw-connected on the rack.

6. A noise- immune linear modulation system according to claim 5, characterized in that: The ratio of the two arms of the third lever is 1:

5.

7. A noise- immune linear modulation system according to claim 6, characterized in that: A plurality of supporting legs are arranged below the rack, and the supporting legs have a buffering function.

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