Intrusion detection equipment based on optical fiber and device applying intrusion detection equipment

Abstract

The invention discloses intrusion detection equipment based on an optical fiber and a device applying the intrusion detection equipment, the intrusion detection equipment based on the optical fiber comprises a sensing optical fiber and an elastic reed, the sensing optical fiber is fixed on the reed, the reed is arranged on an external installation foundation in a suspended or suspended manner, and the sensing optical fiber is fixed on the reed. And the reed can generate vibration in the vertical direction relative to the mounting base. Compared with the prior art, the device has the advantages that the sensing optical fibers are arranged on the reeds capable of vibrating in the vertical direction, invasion vibration borne by an external device can be transmitted to the reeds, and therefore climbing signals of people are transmitted to the sensing optical fibers, disturbance of external noise can be resisted, the influence of the noise is reduced, and the reliability of the device is improved. And the false alarm rate and the missing report rate are reduced.

Description

Technical Field

[0001] The present invention relates to the field of optical technology, and in particular to an intrusion detection device based on optical fiber, and a device using the intrusion detection device. Background Art

[0002] Fiber-optic intrusion detection devices, such as fiber-optic fences, walls, and floors, use a Mach-Zehnder interferometer or a Saggrad interferometer (see Fig.21 and Fig. 22 ). Taking the fiber optic fence as an example, the vibration sensing fiber is arranged on the fence. When the fence encounters an intrusion and shakes, the phase difference between the two beams of light will change, causing the phase of the coherent light that meets at the coupler to change, thereby forming an interference effect. The change in light intensity after interference is used to sense the shaking signal of the fence, thereby determining whether there has been an intrusion.

[0003] The fiber laying method of conventional fiber optic fences is to hang the sensing optical fiber on the fence, or embed the optical fiber in the fence pipe. When the fence shakes, it will drive the sensing optical fiber, thereby generating an interference signal. For example, a fiber optic fence disclosed in a Chinese patent with application number 202120782911.X includes: a fence frame, a fiber optic seat and a fiber optic clamp. The lower part of the fiber optic seat extends outward on both sides to form a pair of extensions. A groove is formed on the top of the fiber optic seat, and an optical fiber is arranged at the bottom of the groove. The upper and lower ends of the fiber optic clamp respectively conflict with the force transmission rod and the optical fiber.

[0004] This type of fiber optic fence has a basic layout of an up-and-down structure. Fig.23 Basically, all the noise is in the horizontal direction, that is, F 1 , such as wind, plant knocking, and when the fence is invaded, the actual signal generated is in the vertical direction, that is, F 2 Therefore, external noise will greatly increase the local noise of the interference signal, thereby covering up the intrusion signal caused by human climbing, resulting in missed judgments, especially in harsh outdoor environments. Due to wind noise, rain, hail, and the knocking of plant branches, it is easy to cause false alarms of fiber optic fences. The high false alarm rate has always been the main obstacle to the large-scale application of fiber optic fences. At the same time, due to cost factors, fiber optic fences do not use fiber optic distributed stress sensing technology, but use ordinary interference methods to demodulate intensity signals or phase differences to determine intrusions, so it is difficult to achieve accurate positioning. Summary of the invention

[0005] The first technical problem to be solved by the present invention is to provide an optical fiber-based intrusion detection device to reduce the false alarm rate and the missed alarm rate in view of the deficiencies in the above-mentioned prior art.

[0006] The second technical problem to be solved by the present invention is to provide a device using the above-mentioned optical fiber-based intrusion detection device.

[0007] The technical solution adopted by the present invention to solve the above-mentioned first technical problem is: an optical fiber-based intrusion detection device, including a sensing optical fiber, characterized in that:

[0008] The intrusion detection device also includes an elastic reed, the sensing optical fiber is fixed on the reed, and the reed is suspended or hung on an external mounting base so that the reed can vibrate in a vertical direction relative to the mounting base.

[0009] By setting the sensing optical fiber on a reed that can vibrate in the vertical direction, the intrusion vibration of the external device can be transmitted to the reed, thereby transmitting the human climbing signal to the sensing optical fiber, which can resist the disturbance of external noise, thereby reducing the impact of noise and reducing the false alarm rate and missed alarm rate.

[0010] Furthermore, in order to facilitate the arrangement of the reed, the reed is connected to the mounting base via a fixing block, and the size of the fixing block is smaller than the size of the reed.

[0011] Furthermore, the fixing block and the mounting base are connected via a first elastic member, thereby improving the sensitivity of the reed.

[0012] Furthermore, a shell is provided on the outer periphery of the reed, and both ends of the sensing optical fiber pass through the outside of the shell, thereby increasing the rigidity of the device.

[0013] The first technical solution adopted by the present invention to solve the second technical problem is: a device using the above-mentioned optical fiber-based intrusion detection device, characterized in that: the device includes multiple optical fiber-based intrusion detection devices, and the reeds of each intrusion detection device have different resonant frequencies. Thus, the intrusion position can be located.

[0014] The second technical solution adopted by the present invention to solve the above second technical problem is: a device using the above-mentioned optical fiber-based intrusion detection device, the device is an optical fiber fence, the optical fiber fence includes a fence, the fence includes a main crossbar at the bottom, the main crossbar serves as the installation base, and the reed is suspended at the bottom of the main crossbar. Since the reed is on the main crossbar at the bottom of the fence, the structure is relatively stable and can greatly resist the disturbance of external noise, thereby greatly reducing the impact of noise.

[0015] Furthermore, the fence also includes a supporting straight bar, a main straight bar and a supporting cross bar, the supporting straight bar and the main straight bar are both arranged vertically, there are at least two supporting straight bars and they are arranged at intervals in the horizontal direction, the main straight bars are arranged at the outermost sides of the straight bar combination formed by the supporting straight bars, the bottom of the supporting straight bar is arranged on the main cross bar, the supporting cross bar is located near the top of the supporting straight bar and extends between the two main straight bars, and the supporting cross bar and the main straight bar are connected by a fixing plate. In this way, the intrusion vibration can be better transmitted.

[0016] The third technical solution adopted by the present invention to solve the above-mentioned second technical problem is: a device using the optical fiber-based intrusion detection device as described above, the device is a fiber optic fence, the fiber optic fence includes a fence, the fence includes a main cross bar located at the bottom and a base located below the main cross bar, the base serves as the installation base, the reed 1 is suspended on the base and is located below the main cross bar, and a linear bearing is provided between the main cross bar and the reed to strike the reed when the main cross bar vibrates.

[0017] The fourth technical solution adopted by the present invention to solve the above-mentioned second technical problem is: a device using the optical fiber-based intrusion detection device as described above, the device is a floor, the floor includes a plurality of floor tile units, the floor tile units include floor tiles, at least one floor tile unit includes the above-mentioned intrusion detection device, and the reed is arranged in the floor tile serving as the installation base.

[0018] The fifth technical solution adopted by the present invention to solve the above-mentioned second technical problem is: a device using the optical fiber-based intrusion detection device as described above, wherein the device is a fence, and the fence includes the intrusion detection device and a wall as the installation base, and the reed is arranged in the wall and close to the top of the wall.

[0019] Compared with the prior art, the advantages of the present invention are: by setting the sensing optical fiber on a reed that can vibrate in the vertical direction, the intrusion vibration of the external device can be transmitted to the reed, thereby transmitting the human climbing signal to the sensing optical fiber, which can resist the disturbance of external noise, thereby reducing the impact of noise and reducing the false alarm rate and missed alarm rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the principle of the optical fiber fence of the first embodiment of the present invention;

[0021] Figure 2 A schematic diagram of a fiber optic fence according to a first embodiment of the present invention;

[0022] Figure 3 A partial front view of the optical fiber fence according to the first embodiment of the present invention;

[0023] Figure 4 A top view of a fiber optic fence according to a first embodiment of the present invention;

[0024] Figure 5 A partial front view of a fiber optic fence according to a second embodiment of the present invention;

[0025] Figure 6 A partial front view of a fiber optic fence according to a third embodiment of the present invention;

[0026] Figure 7 A partial front view of a fiber optic fence according to a fourth embodiment of the present invention;

[0027] Figure 8 A partial front view of a fiber optic fence according to a fifth embodiment of the present invention;

[0028] Fig. 9 is a schematic diagram of a fiber optic fence according to a sixth embodiment of the present invention;

[0029] Fig.10 A partial front view of a fiber optic fence according to a sixth embodiment of the present invention;

[0030] Fig.11 is a schematic diagram of a fiber optic fence according to a seventh embodiment of the present invention;

[0031] Fig.12 A front view of a fiber optic fence according to an eighth embodiment of the present invention;

[0032] Fig.13 for Fig.12 A partial enlarged schematic diagram of Ⅰ;

[0033] Fig.14 for Fig.13 A schematic diagram of an alternative embodiment of a fixing plate in FIG.

[0034] Fig.15 is a schematic diagram of a floor tile unit according to a ninth embodiment of the present invention;

[0035] Fig.16 is a partial schematic diagram of a floor tile unit according to a ninth embodiment of the present invention;

[0036] Fig.17 is a cross-sectional view of a floor tile unit according to a ninth embodiment of the present invention;

[0037] Fig.18 is a schematic diagram of the ground surface of the ninth embodiment of the present invention;

[0038] Fig.19 is a partial schematic diagram of a floor tile unit according to a tenth embodiment of the present invention;

[0039] Fig. 20is a schematic diagram of a wall according to an eleventh embodiment of the present invention;

[0040] Fig.21 It is a schematic diagram of the principle of the existing Mach Zehnder interferometer;

[0041] Fig. 22 It is a schematic diagram of the principle of the existing Saglac interferometer;

[0042] Fig.23 Schematic diagram of the force on the existing fiber optic fence. DETAILED DESCRIPTION

[0043] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals represent the same or similar elements or elements having the same or similar functions.

[0044] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate the orientation or position relationship based on the orientation or position relationship shown in the drawings, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Since the embodiments disclosed in the present invention can be set in different directions, these terms indicating directions are only for illustration and should not be regarded as limitations. For example, "up" and "down" are not necessarily limited to directions opposite to or consistent with the direction of gravity. In addition, the features defined as "first" and "second" may explicitly or implicitly include one or more of such features.

[0045] Embodiment 1

[0046] See also Figure 1, a schematic diagram of the principle of a fiber optic fence, the fiber optic fence includes a fiber optic fence unit 100, the fiber optic fence unit 100 includes an intrusion detection device and a fence 1 as an installation base for the intrusion detection device. The fence 1 includes a support straight rod 11, a main straight rod 12, a support cross rod 13, a main cross rod 14 and a base 15. Among them, the support straight rod 11 and the main straight rod 12 are both vertically arranged, and the support straight rod 11 may have at least two, which are arranged at intervals along the horizontal direction. The main straight rod 12 has two, which are arranged on the outermost sides of the straight rod combination formed by each support straight rod 11. The support cross rod 13 and the main cross rod 14 are both arranged laterally, preferably horizontally. The bottom of the above-mentioned support straight rod 11 is set on the main cross rod 14, and the support cross rod 13 extends between the two main straight rods 12, and is located near the top of the support straight rod 11 to connect each support straight rod 11. The base 15 is located below the main crossbar 14, and the bottom of the main straight bar 12 is arranged on the base 15. The base 15 can be cement or a common material ground. The structure of the fence 1 is prior art and will not be described here.

[0047] The intrusion detection device includes a sensing optical fiber 2. In this embodiment, the main cross bar 14 is the installation base of the sensing optical fiber 2. The sensing optical fiber 2 is arranged at the bottom of the main cross bar 14 and extends in the same direction as the main cross bar 14. Such an installation method can greatly reduce the noise of external shaking.

[0048] See also Figure 2 to Figure 4 Since the main crossbar 14 has a relatively large structural strength, the signal characteristics of human climbing will be greatly weakened. Therefore, the intrusion detection device further includes an elastic reed 3, which can be rectangular, and its length direction is arranged in the same direction as the main crossbar 14. Preferably, the reed 3 is arranged horizontally. The reed 3 is fixed to the bottom of the main crossbar 14 by a fixing block 31, so that the reed 3 is suspended on the main crossbar 14 (arranged at a distance from the main crossbar 14), and the sensing optical fiber 2 is arranged on the upper surface of the reed 3.

[0049] To achieve the suspension setting, the size of the fixed block 31 is smaller than the size of the reed 3. For example, preferably, the length of the fixed block 31 is much smaller than the length L of the reed 3. Preferably, the fixed block 31 is arranged at the middle position in the length direction of the reed 3, so that the parts of the reed 3 on both sides of the fixed block 31 in the length direction are in a suspended state to generate vibration.

[0050] When a person steps on the fence 1 to climb, the main crossbar 14 will produce Figure 3 The vibration in the direction indicated by the arrow A (up and down direction) is transmitted to the reed 3. Since the thickness h of the reed 3 is very small, a large elastic vibration in the vertical direction will be generated. Figure 3This is the direction indicated by the arrow B, thereby transmitting the climbing signal of the person to the sensing optical fiber 2. Since the width d of the reed 3 is relatively large, d / h can be selected to be greater than 5, it is not easy to vibrate in the horizontal direction, so it is extremely insensitive to horizontal noise. The reed 3 is also located on the main crossbar 14 at the bottom of the fence 1, and the structure is relatively stable, which can greatly resist the disturbance of external noise, thereby greatly reducing the impact of noise.

[0051] The fiber optic fence may have a plurality of the above-mentioned fiber optic fence units 100 (such as fiber optic fences divided by area). The reed 3 of each fiber optic fence unit 100 has its own inherent resonant frequency and is sensitive to a specific frequency, thereby changing the thickness and length of the reed 3, and installing reeds 3 with different resonant frequencies under the fences 1 in different areas. When the resonant frequency of the reed 3 is different, the frequency of the interference signal of the sensing optical fiber 2 also changes accordingly. Since the reed 3 generates a vibration with a certain duration, this vibration time will be longer than the climbing time, and the vibration frequency will vary according to the resonant frequency of the reed 3, it is possible to determine which reed 3 has generated the climbing signal based on the signal characteristics (vibration frequency) of the vibration of the reed 3, and to determine which area of ​​the fence 1 has been invaded, thereby achieving positioning. This can solve the problem that ordinary interference fiber optic fences cannot be positioned.

[0052] Of course, the climbing force can also be roughly measured by modifying the structural strength of the reed 3 and the main crossbar 14 of the fence 1, such as by adopting a suitably rigid structure to make it insensitive to the climbing of small animals, such as mice, rabbits, etc., thereby avoiding interference and misjudgment.

[0053] Embodiment 2

[0054] See also Figure 5 In this embodiment, the difference from the above-mentioned embodiment 1 is that the fixing block 31 is arranged at one end of the reed 3 in the length direction, and the sensing optical fiber 2 is arranged on the lower surface of the reed 3.

[0055] Embodiment 3

[0056] See also Figure 6 In this embodiment, the difference from the above-mentioned embodiment 1 is that the reed 3 includes a first reed portion 32 and a second reed portion 33, the first reed portion 32 is rectangular and fixed to the bottom of the fixed block 31, and the second reed portion 33 is a U-shape with a transverse opening, one end of the first reed 32 extends to the second reed portion 33, and the opening side of the second reed portion 33 is away from the first reed portion 32.

[0057] The sensing optical fiber 2 is fixed on the lower surface of the second spring portion 32 , that is, fixed at the bottommost position of the U-shaped structure.

[0058] Embodiment 4

[0059] See also Figure 7 In this embodiment, the difference from the above-mentioned embodiment 1 is that the fixing block 31 and the main cross bar 14 are connected by a first elastic member 34. Preferably, the first elastic member 34 can be a spring.

[0060] Embodiment 5

[0061] See also Figure 8 In this embodiment, the difference from the fourth embodiment is that the combination of the fixing block 31 and the first elastic member 34 has two groups arranged at intervals in the transverse direction.

[0062] Embodiment 6

[0063] See also Fig. 9 and Fig.10 In this embodiment, the difference from the above-mentioned embodiment 1 is that the reed 3 is fixed on the base 15 by a fixing block 31, and is suspended at a distance from the base 15. The sensing optical fiber 2 and the reed 3 are located between the main crossbar 14 and the base 15. The fixing block 31 can be set at one end of the reed 3 in the length direction, and the middle position of the reed 3 in the length direction can be connected to the main crossbar 14 through a linear bearing 35. A second elastic member 36 can be set on the lower surface of the reed 3, at a position corresponding to the linear bearing 35, and connected between the reed 3 and the base 15. Preferably, the second elastic member 36 can be a spring.

[0064] The above structure constitutes a knocking type vibration sensor, thereby further reducing the influence of wind noise, and the horizontal noise will not cause the vibration of the reed 3. When someone climbs on the fence 1, the linear bearing 35 knocks the reed 3, causing the elastic vibration of the reed 3. The second elastic member 36 can limit the vibration amplitude of the reed 3.

[0065] The corresponding structures in the second to fifth embodiments may also be replaced by the structure of this embodiment.

[0066] Embodiment 7

[0067] See also Fig.11 In this embodiment, on the basis of the first embodiment, a housing 37 is provided on the outer periphery of the reed 3, and the two ends of the sensing optical fiber 2 are passed out of the housing 37. Alternatively, the reed 3 and the sensing optical fiber 2 are installed in a pipe (not shown) of the fence 1. At the same time, the rigidity between the main cross bar 14 and the main straight bar 12 can be increased, and the wind noise transmitted from the upper fence 1 can be further reduced. At the same time, the main cross bar 14 is partially made into a flat shape, which helps to increase the horizontal rigidity, reduce the noise transmission in the horizontal direction, and appropriately increase the deformation in the vertical direction for identifying climbing signals.

[0068] The corresponding structures in the second to sixth embodiments may also be replaced by the structure of this embodiment.

[0069] Embodiment 8

[0070] See also Fig.12 and Fig.13 In this embodiment, based on the first embodiment, a fixing plate 16 is provided between the end of the supporting cross bar 13 and the main straight bar 12. The fixing plate 16 is a thin plate, and its longitudinal cross section may be an inverted L-shape, and the two sides of the L-shape are fixed to the supporting cross bar 13 and the main straight bar 12 respectively.

[0071] Therefore, when climbing, unless only the main straight rod 12 is touched, the downward force will be smoothly transmitted to the main cross bar 14 at the bottom of the fence 1, causing the reed 3 to vibrate.

[0072] See also Fig.14 Alternatively, the fixing plate 16 may be in a straight line shape, and a lateral raised portion may be provided at the connection between the main straight rod 12 and the supporting cross rod 13 , and the main straight rod 12 and the supporting cross rod 13 may be fixed on both lateral sides of the fixing plate 16 , respectively.

[0073] The corresponding structure of this embodiment can also be adopted in embodiments 2 to 7.

[0074] Embodiment 9

[0075] See also Figure 15 to Figure 18 , shows another application embodiment of the fiber-optic-based intrusion detection device, which is a floor. The floor includes a plurality of floor tile units 200, at least one floor tile unit 200, such as each floor tile unit 200 includes the above-mentioned intrusion detection device and a floor tile 201 as an installation base for the intrusion detection device. The reed 3 is suspended or suspended in the floor tile 201 of the floor tile unit 200, that is, the floor tile 201 has a hollow cavity to form a first installation cavity 202, the reed 3 is arranged in the first installation cavity 202, and at least one of the bottom surface and the top surface of the floor tile 201 forming the first installation cavity 202 is not in direct contact with the reed 3, that is, the reed 3 is not in direct contact with the bottom surface or the top surface of the floor tile 201 forming the first installation cavity 202. The sensing optical fiber 2 passes through the floor tile 201. At this time, the d / h of the reed 3 can be selected to be greater than 3.

[0076] The resonant frequencies of the reeds 3 of each floor tile unit 200 are different. The different vibration frequencies can be used to identify which floor tile unit 200 is excited, thereby determining the intrusion location.

[0077] Embodiment 10

[0078] See also Fig.19 In this embodiment, the difference from the above-mentioned ninth embodiment is that the sensing optical fiber 2 in the ninth embodiment is a straight line shape, while the sensing optical fiber 2 in this embodiment is an L shape.

[0079] Embodiment 11

[0080] See also Fig. 20 , shows another application embodiment of the optical fiber-based intrusion detection device, which is a fence. It includes an intrusion detection device and a wall 300 as an installation base for the intrusion detection device, and the reed 3 is suspended or suspended in the wall 300. A hollow second installation cavity 301 is formed near the top of the wall 300, and the reed 3 is arranged in the second installation cavity 301 of the wall 300. The reed 3 is also not in direct contact with the bottom surface or top surface of the wall 301 that constitutes the second installation cavity 301. The sensing optical fiber 2 passes through the wall 300.

[0081] When a person attempts to climb over the wall, it will cause vibrations at the top, thereby driving the vibrations of the sensing optical fiber 2. The intrusion location can also be determined by identifying the vibration frequency (multiple intrusion detection devices are set up, and the reed 3 of each intrusion detection device has a different resonant frequency).

Claims

1. An optical fiber-based intrusion detection device, comprising a sensing optical fiber (2), characterized in that: The intrusion detection device also includes an elastic reed (3), the sensing optical fiber (2) is fixed on the reed (3), and the reed (3) is suspended or hung on an external mounting base so that the reed (3) can vibrate in a vertical direction relative to the mounting base.

2. The optical fiber-based intrusion detection device according to claim 1, characterized in that: The reed (3) is connected to the installation base via a fixing block (31), and the size of the fixing block (31) is smaller than the size of the reed (3).

3. The optical fiber-based intrusion detection device according to claim 2, characterized in that: The fixing block (31) and the installation base are connected via a first elastic member (34).

4. The optical fiber-based intrusion detection device according to claim 1, characterized in that: A housing (37) is provided on the outer periphery of the reed (3), and two ends of the sensing optical fiber (2) extend out of the housing (37).

5. A device using the optical fiber-based intrusion detection device according to any one of claims 1 to 4, characterized in that: The device comprises a plurality of optical fiber-based intrusion detection devices, and the reeds (3) of the intrusion detection devices have different resonant frequencies.

6. A device using an optical fiber-based intrusion detection device as described in any one of claims 1 to 4, wherein the device is a fiber optic fence, the fiber optic fence comprises a fence (1), the fence (1) comprises a main cross bar (14) located at the bottom, the main cross bar (14) serves as the installation base, and the reed (3) is suspended at the bottom of the main cross bar (14).

7. The device according to claim 6, characterized in that: The fence (1) further comprises a supporting straight bar (11), a main straight bar (12) and a supporting cross bar (13); the supporting straight bar (11) and the main straight bar (12) are both arranged vertically; the supporting straight bar (11) has at least two and are arranged at intervals in the horizontal direction; the main straight bars (12) are arranged at the outermost sides of a straight bar combination formed by each supporting straight bar (11); the bottom of the supporting straight bar (11) is arranged on the main cross bar (14); the supporting cross bar (13) is located near the top of the supporting straight bar (11) and extends between the two main straight bars (12); the supporting cross bar (13) and the main straight bar (12) are connected by a fixing plate (16).

8. A device using an optical fiber-based intrusion detection device as described in claim 1, 2 or 4, wherein the device is a fiber optic fence, the fiber optic fence includes a fence (1), the fence (1) includes a main crossbar (14) located at the bottom and a base (15) located below the main crossbar (14), the base (15) serves as the installation base, the reed (3) 1 is suspended on the base (15) and located below the main crossbar (14), and a linear bearing (35) is provided between the main crossbar (14) and the reed (3) for striking the reed (3) when the main crossbar (14) vibrates.

9. A device using the optical fiber-based intrusion detection device as described in any one of claims 1 to 4, wherein the device is a floor, the floor includes a plurality of floor tile units (200), the floor tile units (200) include floor tiles (201), at least one floor tile unit (200) includes the above-mentioned intrusion detection device, and the reed (3) is arranged in the floor tile (201) serving as the installation base.

10. A device using the optical fiber-based intrusion detection device as described in any one of claims 1 to 4, wherein the device is a fence, the fence includes the intrusion detection device and a wall (300) serving as the installation base, and the reed (3) is arranged inside the wall (300) and close to the top of the wall (300).

Images