Mobile leaky coaxial cable and manufacturing method thereof

Abstract

The present invention relates to a mobile leaky coaxial cable and a method for manufacturing the same. The present invention comprises an inner conductor; an insulating layer covering the outer surface of the inner conductor; a shielding layer covering the outer surface of the insulating layer, wherein the shielding layer is made of a metal strip having a corrugated structure, and the shielding layer is provided with four groups of slots to achieve leakage of electromagnetic wave signals; wherein each of the slots is provided at the crest of the corrugated structure, and the four groups of slots are evenly distributed along the circumference of the shielding layer and spaced 90° apart from each other; a sheath layer covering the outer surface of the shielding layer; a flame-retardant rope provided inside the sheath layer, and a plurality of the flame-retardant ropes are distributed on the long diagonal line and symmetrically distributed on both sides of the center of the long diagonal line. The present invention can achieve rapid laying and rapid recovery, and can achieve wireless signal coverage without considering the installation direction.

Description

Technical Field

[0001] The present invention relates to the technical field of wireless communications, and in particular to a mobile leaky coaxial cable and a manufacturing method thereof. Background Art

[0002] Traditional leaky coaxial cables are mainly used in closed or semi-closed places such as tunnels, mines, subways, and basements to compensate for wireless signal blind spots and improve wireless communication coverage capabilities.

[0003] Due to the complex usage scenarios of leaky coaxial cables, existing leaky coaxial cables need to be laid using installation fixtures during the actual laying process. Specifically, before the leaky coaxial cable is used, the actual laying line needs to be constructed first. First, a leaky coaxial cable fixture that adapts to the scenario needs to be designed according to the usage scenario; second, holes are punched on the wall or fixed bracket for fixture fixation, and then the fixture is fixed to the wall with expansion bolts, or the bolts and bracket are fixed together on the existing bracket; finally, the leaky coaxial cable is installed on the fixture, and it is necessary to make certain twists and adjustments according to the installation direction of the leaky coaxial cable to keep the leaky coaxial cable signal radiation direction facing the receiving device.

[0004] However, the existing structure of leaky coaxial cables has the following defects: the installation and construction are complicated, and special scenarios require a fixture fixing solution designed according to the actual on-site environment to meet the requirements of leaky coaxial cable installation. The installation of leaky coaxial cables requires supporting facilities such as fixtures, bolts or brackets. The fixtures must be fixed first, and then the leaky coaxial cables are installed; the fixtures and leaky coaxial cables are inconvenient to recycle after installation and are suitable for long-term use in fixed places; the installation of leaky coaxial cables has a certain directionality and requires appropriate adjustment during installation; the radiation of leaky coaxial cables is directional, and there is no signal when facing away from the radiation direction; in emergency rescue and fire rescue, when underground or large building indoor communications are destroyed and there is temporarily no communication infrastructure, the use of traditional wireless communication coverage in this scenario cannot quickly respond for rescue, relief, and positioning. Summary of the Invention

[0005] To this end, the present invention provides a mobile leaky coaxial cable and a manufacturing method thereof, which adopts non-fixed laying, can achieve rapid laying and quick recovery, and can achieve wireless signal coverage without considering the installation direction.

[0006] In order to solve the above technical problems, the present invention provides a mobile leaky coaxial cable, comprising:

[0007] inner conductor;

[0008] an insulating layer covering the outer surface of the inner conductor;

[0009] a shielding layer covering the outer surface of the insulating layer, the shielding layer being made of a metal strip having a corrugated structure and having four groups of slots disposed thereon to prevent leakage of electromagnetic wave signals; wherein each of the slots is disposed at a crest of the corrugated structure, and the four groups of slots are evenly distributed along the circumference of the shielding layer and spaced 90 degrees apart from each other;

[0010] a sheath layer covering the outer surface of the shielding layer; wherein the cross-section of the sheath layer is a diamond-shaped structure having a long diagonal and a short diagonal, the centerline of the angle formed by two adjacent groups of slots coincides with the long diagonal or the short diagonal; the center of the inner conductor coincides with the center of the diamond structure; the edges of the diamond structure are suitable for contacting the mounting plane, and after contacting the mounting plane, the ratio of the four groups of slots covering the circumference of the shielding layer is configured to achieve a cable signal coverage angle greater than 180°;

[0011] The flame retardant rope is arranged inside the sheath layer and is used to achieve flame retardant physical isolation. A plurality of the flame retardant ropes are distributed on the long diagonal line and symmetrically distributed along both sides of the center of the long diagonal line.

[0012] In one embodiment of the present invention, the four groups of slots together cover 50% to 90% of the circumference of the shielding layer.

[0013] In one embodiment of the present invention, the inner conductor includes a single or multiple metal conductors, and is made of solid, hollow metal material or composite metal material.

[0014] In one embodiment of the present invention, the insulating layer is made of polyethylene, polyvinyl chloride or polytetrafluoroethylene and has a solid or foamed structure.

[0015] In one embodiment of the present invention, the sheath layer is made of low-smoke halogen-free flame retardant material.

[0016] In one embodiment of the present invention, the flame retardant rope is a basalt fiber rope.

[0017] In one embodiment of the present invention, the flame retardant rope includes a small-diameter flame retardant rope and a large-diameter flame retardant rope, and one small-diameter flame retardant rope and one large-diameter flame retardant rope are arranged on both sides of the long diagonal center respectively, and the small-diameter flame retardant rope is located on the side away from the long diagonal center.

[0018] The present invention also provides a method for manufacturing a mobile leaky coaxial cable, which is used to manufacture the mobile leaky coaxial cable, comprising:

[0019] S1. twisting a single or multiple metal conductors to obtain an inner conductor;

[0020] S2. Coating the outer surface of the inner conductor with a solid or foamed insulating layer by an extrusion process, wherein the insulating layer is made of polyethylene, polyvinyl chloride or polytetrafluoroethylene;

[0021] S3. Wrapping the outer surface of the insulating layer with a metal strip longitudinally, welding the overlapped seams of the metal strip, and then corrugating the outer surface of the insulating layer to form a shielding layer having a corrugated structure with periodic peaks and troughs;

[0022] S4. Providing a hollow tubular mold, wherein the central hole section of the hollow tubular mold is provided with four symmetrically arranged cutting plane grooves spaced 90 degrees apart; passing the shielding layer through the hollow tubular mold, with a gap of 2 to 5 mm between the central hole section of the hollow tubular mold and the shielding layer; and disposing a milling tool corresponding to each cutting plane groove;

[0023] Passing the shielding layer through the hollow tubular mold, passing the milling tool through the cutting plane groove, and cutting the crest of the corrugated structure of the shielding layer, thereby processing four groups of slots evenly distributed along the circumference of the shielding layer and spaced 90 degrees apart from each other;

[0024] S5. Providing a sheath extrusion die, wherein the sheath extrusion die includes an extrusion die core and an extrusion die sleeve, wherein the extrusion die core includes a tapered flow guide portion and a threading portion located at one end of the tapered flow guide portion;

[0025] The extrusion die sleeve is provided with a die cavity suitable for gap matching with the extrusion die core, and a diamond-shaped hole located on the outer periphery of the threading portion is provided at the end of the die cavity;

[0026] The threading portion includes a shielding layer threading hole and flame retardant rope threading holes located on both sides of the shielding layer threading hole; the shielding layer threading hole is suitable for passing the shielding layer, and the flame retardant rope threading hole is suitable for passing the flame retardant rope; the shielding layer threading hole is a square hole, and the diagonal of the diamond hole coincides with the diagonal of the shielding layer threading hole;

[0027] Adjust the long diagonal of the diamond hole to be in a horizontal state, and adjust the shielding layer with the slotted holes so that the center line of the angle formed by two adjacent groups of slotted holes coincides with the long diagonal or the short diagonal of the diamond hole, and then insert it into the shielding layer threading hole, with a gap of 1 to 5 mm between the shielding layer threading hole and the shielding layer;

[0028] S6. The sheath extrusion die is installed on the extruder head. The sheath material is extruded from the extruder head, flows through the tapered guide portion, and is extruded from the gap between the extrusion die core and the extrusion die sleeve. Simultaneously, during the sheath extrusion process, a flame retardant rope made of basalt fiber is introduced into the flame retardant rope threading hole. The sheath material covers the shielding layer and the flame retardant rope, ultimately forming a sheath layer.

[0029] S7. After the sheath layer is coated, the cable is cooled and shaped to obtain a finished mobile leaky coaxial cable.

[0030] In one embodiment of the present invention, the milling tool is driven by a servo motor, with a single-tool power of 50 to 500 W, a rotation speed of 50 to 500 rpm, and a tool step speed of 0.1 to 5 mm / s. All the milling tools are synchronized to start and stop and have consistent rotation speed through the same servo control system to ensure consistency in the slot processing size.

[0031] In one embodiment of the present invention, the dimensions of each cutting plane groove are: 50 mm in length and 10-40 mm in width; the dimensions of the slot hole are: 10-30 mm in length and 3-15 mm in width.

[0032] The above technical solution of the present invention has the following advantages over the prior art:

[0033] The present invention discloses a mobile leaky coaxial cable and a manufacturing method thereof. The mobile leaky coaxial cable is laid in a non-fixed manner and is laid on the ground along the line. The mobile leaky coaxial cable can be quickly retrieved after use, is easy to use, and can be reused.

[0034] The mobile leaky coaxial cable of the present invention can be quickly laid without the need for fixed installation;

[0035] The mobile leaky coaxial cable of the present invention does not require the use of supporting parts, thus saving construction costs;

[0036] The mobile leaky coaxial cable of the present invention has a diamond-shaped structure, and only two sides of the diamond-shaped structure will touch the ground, and both can achieve wireless signal coverage regardless of the installation direction;

[0037] The mobile leaky coaxial cable of the present invention has a radio electromagnetic wave signal coverage range of more than 180 degrees, which is wider than the coverage range of traditional leaky cables;

[0038] A mobile leaky coaxial cable of the present invention has a flame-retardant physical isolation structure, which can protect the leaky cable itself, thereby ensuring wireless communication needs during fire. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to make the contents of the present invention more clearly understood, the present invention is further described in detail below based on specific embodiments of the present invention in conjunction with the accompanying drawings.

[0040] Figure 1 It is a cross-sectional view of the mobile leaky coaxial cable placed on the ground in Example 1 of the present invention.

[0041] Figure 24 is a cross-sectional view of a mobile leaky coaxial cable in embodiment 1 of the present invention.

[0042] Figure 3 Schematic diagram of the structure of the hollow tubular mold in Example 2 of the present invention.

[0043] Figure 4 It is a schematic diagram of the use status of the hollow tubular mold in Example 2 of the present invention.

[0044] Figure 5 It is a structural schematic diagram of one side of the extrusion core in Example 2 of the present invention.

[0045] Figure 6 It is a schematic structural diagram of the other side of the extrusion core in Example 2 of the present invention.

[0046] Figure 7 It is a structural schematic diagram of one side of the extrusion die sleeve in Example 2 of the present invention.

[0047] Figure 8 It is a schematic structural diagram of the other side of the extrusion die sleeve in Example 2 of the present invention.

[0048] Description of the accompanying drawings:

[0049] 1. Inner conductor;

[0050] 2. Insulation layer;

[0051] 3. Shielding layer; 31. Slot;

[0052] 4. Sheath layer;

[0053] 5. Flame retardant rope; 5a. Small diameter flame retardant rope; 5b. Large diameter flame retardant rope;

[0054] 6. Extrusion die core; 61. Conical guide portion; 62. Threading portion; 621. Shielding layer threading hole; 622. Flame retardant rope threading hole;

[0055] 7. Extrusion die sleeve; 71. Die cavity; 72. Diamond hole;

[0056] 8. Hollow tubular mold; 81. Cutting plane groove; 82. Milling tool. DETAILED DESCRIPTION

[0057] The present invention will be further described below with reference to the accompanying drawings and specific embodiments so that those skilled in the art can better understand the present invention and implement it. However, the embodiments are not intended to limit the present invention.

[0058] In the present invention, if directions (up, down, left, right, front and back) are described, it is only for the convenience of describing the technical solution of the present invention, and does not indicate or imply that the technical features referred to must have a specific orientation, be constructed and operate in a specific orientation. Therefore, it cannot be understood as a limitation of the present invention.

[0059] In the present invention, "several" means one or more, "multiple" means more than two, "greater than," "less than," "exceeds," etc. are understood to exclude the number itself; "above," "below," "within," etc. are understood to include the number itself. In the description of the present invention, the use of "first" or "second" is solely for the purpose of distinguishing technical features and is not to be construed as indicating or implying relative importance, implicitly specifying the number of the indicated technical features, or implicitly specifying the order of the indicated technical features.

[0060] In the present invention, unless otherwise expressly defined, terms such as "disposed," "installed," and "connected" should be interpreted broadly. For example, they may refer to direct connection or indirect connection through an intermediate medium; fixed connection or detachable connection or integral molding; mechanical connection or electrical connection or mutual communication; and internal connection between two components or interaction between two components. Those skilled in the art can reasonably determine the specific meanings of the above terms in the present invention based on the specific content of the technical solution.

[0061] Example 1

[0062] Reference Figure 1 、 Figure 2 As shown, a mobile leaky coaxial cable of this embodiment includes:

[0063] Inner conductor 1;

[0064] An insulating layer 2, covering the outer surface of the inner conductor 1, for providing electrical insulation and structural support;

[0065] A shielding layer 3 covers the outer surface of the insulating layer 2. The shielding layer 3 is made of a metal strip with a corrugated structure and is provided with four groups of slots 31 to prevent leakage of electromagnetic wave signals and achieve wireless communication. Each slot 31 is provided at a crest of the corrugated structure. The four groups of slots 31 are evenly (co-circularly) distributed along the circumference of the shielding layer 3 and spaced 90° apart from each other. The use of the corrugated structure of the shielding layer 3 can improve the tensile and bending resistance in the field of use.

[0066] The sheath layer 4 covers the outer surface of the shielding layer 3; wherein the cross section of the sheath layer 4 is a diamond structure with a long diagonal line ( Figure 2 Middle b) and short diagonal ( Figure 2In a), the center line of the angle formed by the two adjacent groups of slots 31 ( Figure 2 c) coincides with the long diagonal or the short diagonal; the center of the inner conductor 1 coincides with the center of the rhombus structure; the edge of the rhombus structure is suitable for contacting a mounting plane (such as the ground), and after contacting the mounting plane, the ratio of the total coverage of the circumference of the shielding layer 3 by the four groups of slots 31 is configured to achieve a cable signal coverage angle greater than 180°;

[0067] The flame retardant rope 5 is arranged inside the sheath layer 4 to achieve flame retardant physical isolation and protect the cable; wherein, multiple flame retardant ropes 5 are distributed on the long diagonal line and symmetrically distributed on both sides of the center of the long diagonal line.

[0068] By providing a diamond-shaped sheath layer 4 and four groups of slots 31 evenly distributed around the shield layer 3 and spaced 90° apart, when the leaky coaxial cable is placed on the ground in any direction, the edges of the diamond structure always touch the ground, and the electromagnetic wave signals radiated from a pair of adjacent slots 31 are always directed above the ground. This ensures that the cable's signal coverage angle exceeds 180°, achieving complete signal coverage above the ground. The diamond-shaped sheath layer 4 and the slots 31 of the shield layer 3 combine to ensure signal coverage regardless of cable placement, eliminating the need to consider the directionality of the leaky cable, saving time. The flame-retardant rope 5 provides flame-retardant physical isolation and protects the cable itself.

[0069] Specifically, the four groups of slots 31 cover 50% to 90% of the circumference of the shielding layer 3. The size of the slots 31 is specifically designed according to the outer diameter of the shielding layer 3. By setting a proportion of 50% to 90%, a signal coverage angle greater than 180° can be achieved.

[0070] In conventional industry designs, coupled leaky cables are slotted on either one or both sides, and their electromagnetic radiation energy diffuses in a concentric circle manner, with a relatively uniform coverage range. The radiation angle of a coupled leaky cable is typically between ±60° and ±90° (i.e., the omnidirectional coverage angle is 120°~180°). However, in this embodiment, the slots on all four sides ensure that the radiation angle fully meets 180° omnidirectional coverage.

[0071] It should be noted that the number of each group of slots 31 is one, or there are multiple slots 31 spaced apart along the length direction of the cable; the corrugated structure on the shielding layer 3 extends along the length direction.

[0072] It is understandable that when the diamond-shaped sheath layer 4 is placed forward or reversely, the shielding layer 3 with the corrugated structure always has a group of two adjacent slots 31 that radiate electromagnetic wave signals capable of achieving a signal coverage angle greater than 180°.

[0073] When the rhombus-shaped sheath layer 4 is laid in a leaky coaxial cable, only the two adjacent sides of the rhombus structure located on one side of the long diagonal line will contact the ground. However, no matter which side contacts the ground, two of the four groups of slots 31 can radiate electromagnetic wave signals to the ground.

[0074] In addition, even if the leaky coaxial cable is twisted during hasty laying in a complex environment, the twisted length of the leaky coaxial cable in this embodiment is set to be only 3-5 times the length of the long diagonal of the diamond structure, and two of the four slots 31 on the corrugated structure shield can radiate electromagnetic wave signals to the ground.

[0075] Specifically, the ratio of the long diagonal to the short diagonal of the diamond structure is greater than 5:1, ensuring a relatively stable placement on the ground.

[0076] Specifically, the inner conductor 1 includes a single or multiple metal conductors and is made of solid, hollow metal material or composite metal material.

[0077] Specifically, the insulating layer 2 is made of polyethylene, polyvinyl chloride or polytetrafluoroethylene, and has a solid or foamed structure.

[0078] Specifically, the sheath layer 4 is made of low-smoke halogen-free flame retardant material.

[0079] Specifically, the flame retardant rope 5 includes a small-diameter flame retardant rope 5a and a large-diameter flame retardant rope 5b, and one small-diameter flame retardant rope 5a and one large-diameter flame retardant rope 5b are arranged on both sides of the long diagonal center, and the small-diameter flame retardant rope 5a is located on the side away from the long diagonal center.

[0080] When one side of the diamond-shaped sheath layer 4 contacts the ground, when a fire source on the ground burns to the mobile leaky coaxial cable, the sheath layer 4 itself is flame retardant. Even if the fire spreads to the flame retardant rope 5, the flame retardant rope 5 has high flame retardancy and can achieve physical isolation. The small-diameter flame retardant rope 5a is the first line of defense for physical isolation, and the large-diameter flame retardant rope 5b is the second line of defense.

[0081] Furthermore, the small-diameter flame-retardant rope 5a is positioned near the edge of the long diagonal line, allowing the leaky coaxial cable to twist at a certain angle. This twist reduces the overall diamond-shaped length of the mobile leaky coaxial cable, facilitating cable retraction and deployment. The flexibility of the flame-retardant rope 5 prevents excessive internal stress during dynamic cable movements (such as retraction, bending, and compression), thereby enhancing the structural adaptability.

[0082] The flame retardant rope 5 also has a certain tensile strength, and can withstand violent pulling in complex environments, thus protecting the mobile leaky coaxial cable.

[0083] Flame-retardant rope 5 is a basalt fiber rope made from volcanic rock melted and drawn at high temperatures. Its primary component is silicate, making it non-combustible and fire-resistant up to 1200°C. It neither burns nor carbonizes in fire. It maintains structural stability at high temperatures, boasts high fiber strength, can withstand mechanical stress, and has a smooth, wear-resistant surface.

[0084] Example 2

[0085] This embodiment provides a method for manufacturing a mobile leaky coaxial cable, which is used to manufacture the mobile leaky coaxial cable, comprising:

[0086] S1. Twisting a single or multiple metal conductors to obtain an inner conductor 1.

[0087] S2. The outer surface of the inner conductor 1 is coated with an insulating layer 2 having a solid or foamed structure by an extrusion process. The insulating layer 2 is made of polyethylene, polyvinyl chloride or polytetrafluoroethylene.

[0088] S3. The outer surface of the insulating layer 2 is longitudinally wrapped with a metal strip, and the overlapped seams of the metal strip are welded, and then processed by a corrugation process to form a shielding layer 3 with a corrugated structure having periodic peaks and troughs.

[0089] S4, reference Figure 3 As shown, a hollow tubular mold 8 is provided, wherein the central hole section of the hollow tubular mold 8 is provided with four cutting plane grooves 81 symmetrically arranged and spaced 90 degrees apart; the shielding layer 3 is passed through the hollow tubular mold 8, and the gap between the central hole section of the hollow tubular mold 8 and the shielding layer 3 is 2 to 5 mm; a milling tool 82 is correspondingly arranged at each cutting plane groove 81; the dimensions of each cutting plane groove 81 are: 50 mm in length and 10 to 40 mm in width;

[0090] Reference Figure 4 As shown, during cutting, the shielding layer 3 is passed through the hollow tubular mold 8, the milling tool 82 passes through the cutting plane groove 81, and the peak part of the corrugated structure of the shielding layer 3 is cut, thereby processing four groups of slots 31 evenly distributed along the circumference of the shielding layer 3 and spaced 90° from each other.

[0091] The milling cutters 82 are driven by servo motors, each with a power of 50 to 500W, a rotational speed of 50 to 500 rpm, and a tool stepping speed of 0.1 to 5 mm / s. All milling cutters 82 are synchronized and rotated at the same speed via a common servo control system, ensuring consistent dimensional consistency of the slots 31. The slots 31 are designed to meet communication requirements based on the dimensions of the corrugated shielding layer 3. In this embodiment, the slots 31 are 10 to 30 mm long (along the cable's radial direction) and 3 to 15 mm wide (along the cable's axial direction).

[0092] S5. Reference Figures 5 to 8 As shown, a sheath extrusion die is provided, the sheath extrusion die includes an extrusion die core 6 and an extrusion die sleeve 7, the extrusion die core 6 includes a tapered guide portion 61 and a threading portion 62 located at one end of the tapered guide portion 61;

[0093] The extrusion die sleeve 7 is provided with a die cavity 71 suitable for gap fitting with the extrusion die core 6, and a diamond-shaped hole 72 located on the outer periphery of the threading portion 62 is provided at the end of the die cavity 71;

[0094] The threading portion 62 includes a shielding layer threading hole 621 and flame-retardant rope threading holes 622 located on both sides of the shielding layer threading hole 621; the shielding layer threading hole 621 is suitable for passing the shielding layer 3, and the flame-retardant rope threading hole 622 is suitable for passing the flame-retardant rope 5; the shielding layer threading hole 621 is a square hole, and the diagonal of the diamond hole 72 coincides with the diagonal of the shielding layer threading hole 621;

[0095] Adjust the long diagonal of the diamond hole 72 to be in a horizontal state, and adjust the shielding layer 3 with the slotted holes 31 so that the center line of the angle formed by two adjacent groups of slotted holes 31 remains coincident with the long diagonal or the short diagonal of the diamond hole 72 (to ensure that the corrugated shielding layer 3 can smoothly pass through the extrusion die core 6 in a certain direction), and then feed it into the shielding layer threading hole 621. The gap between the shielding layer threading hole 621 and the shielding layer 3 is 1 to 5 mm; to ensure that the shielding layer 3 can smoothly pass through the shielding layer threading hole 621 to avoid getting stuck.

[0096] It should be noted that the center line of the angle formed by two adjacent groups of slots 31 in the shielding layer 3 must be kept horizontal before entering the sheath extrusion core 6. This must be done before entering the extruder. Otherwise, the cable will be twisted, and it will be impossible to ensure that the center line of the angle formed by the two adjacent groups of slots 31 coincides with the long diagonal or the short diagonal of the sheath layer 4, which will affect the position of the slots 31 and thus affect the signal coverage angle.

[0097] S6. The sheath extrusion die is installed on the extruder head. The sheath material is extruded from the extruder head, flows through the tapered guide portion 61, and is extruded from the gap between the extrusion die core 6 and the extrusion die sleeve 7. At the same time, during the sheath extrusion process, a flame retardant rope 5 made of basalt fiber is introduced into the flame retardant rope threading hole 622. The sheath material covers the shielding layer 3 and the flame retardant rope 5, and finally forms a sheath layer 4.

[0098] S7, after the sheath layer 4 is coated, the cable is cooled and shaped to obtain a finished mobile leaky coaxial cable.

[0099] Finally, it should be noted that the above specific implementation methods are only used to illustrate the technical solutions of the present invention and are not limiting. Although the present invention has been described in detail with reference to examples, those skilled in the art should understand that the technical solutions of the present invention can be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A mobile leaky coaxial cable, characterized in that: include: inner conductor (1); an insulating layer (2) covering the outer surface of the inner conductor (1); A shielding layer (3) covers the outer surface of the insulating layer (2), wherein the shielding layer (3) is made of a metal strip having a corrugated structure, and four groups of slots (31) are provided on the shielding layer (3) to achieve leakage of electromagnetic wave signals; wherein each of the slots (31) is provided at a crest of the corrugated structure, and the four groups of slots (31) are evenly distributed along the circumference of the shielding layer (3) and are spaced 90 degrees apart from each other; A sheath layer (4) covers the outer surface of the shielding layer (3); wherein the cross section of the sheath layer (4) is a diamond structure and has a long diagonal and a short diagonal, and the center line of the angle formed by two adjacent groups of slots (31) coincides with the long diagonal or the short diagonal; the center of the inner conductor (1) coincides with the center of the diamond structure; the edge of the diamond structure is suitable for contacting with the installation plane, and after contacting with the installation plane, the ratio of the four groups of slots (31) covering the circumference of the shielding layer (3) is configured to achieve a cable signal coverage angle greater than 180°; The flame retardant rope (5) is arranged inside the sheath layer (4) and is used to achieve flame retardant physical isolation. A plurality of the flame retardant ropes (5) are distributed on the long diagonal line and symmetrically distributed along both sides of the center of the long diagonal line.

2. A mobile leaky coaxial cable according to claim 1, characterized in that: The four groups of slots (31) together cover 50% to 90% of the circumference of the shielding layer (3).

3. The mobile leaky coaxial cable according to claim 1, characterized in that: The inner conductor (1) comprises a single or multiple metal conductors and is made of solid, hollow metal material or composite metal material.

4. The mobile leaky coaxial cable according to claim 1, characterized in that: The material of the insulating layer (2) includes polyethylene, polyvinyl chloride or polytetrafluoroethylene, and adopts a solid or foamed structure.

5. The mobile leaky coaxial cable according to claim 1, characterized in that: The sheath layer (4) is made of low-smoke halogen-free flame retardant material.

6. The mobile leaky coaxial cable according to claim 1, characterized in that: The flame retardant rope (5) is made of basalt fiber rope.

7. The mobile leaky coaxial cable according to claim 1, characterized in that: The flame retardant rope (5) comprises a small-diameter flame retardant rope (5a) and a large-diameter flame retardant rope (5b), and one small-diameter flame retardant rope (5a) and one large-diameter flame retardant rope (5b) are arranged on both sides of the long diagonal center, respectively, and the small-diameter flame retardant rope (5a) is located on the side away from the long diagonal center.

8. A method for manufacturing a mobile leaky coaxial cable, used for manufacturing the mobile leaky coaxial cable according to any one of claims 1 to 7, characterized in that: include: S1. twisting a single or multiple metal conductors to obtain an inner conductor (1); S2. Coating a solid or foamed insulating layer (2) on the outer surface of the inner conductor (1) by an extrusion process, wherein the insulating layer (2) is made of polyethylene, polyvinyl chloride or polytetrafluoroethylene; S3, longitudinally wrapping a metal strip on the outer surface of the insulating layer (2), welding the overlapped seams of the metal strip, and then forming a shielding layer (3) having a corrugated structure with periodic peaks and troughs through a corrugation process; S4. Providing a hollow tubular mold (8), wherein the central hole section of the hollow tubular mold (8) is provided with four cutting plane grooves (81) arranged symmetrically and spaced 90 degrees apart; passing the shielding layer (3) through the hollow tubular mold (8), wherein the gap between the central hole section of the hollow tubular mold (8) and the shielding layer (3) is 2 to 5 mm; and disposing a milling tool (82) corresponding to each of the cutting plane grooves (81); The shielding layer (3) is passed through the hollow tubular mold (8), the milling tool (82) is passed through the cutting plane groove (81), and the crest portion of the corrugated structure of the shielding layer (3) is cut, thereby processing four groups of slots (31) evenly distributed along the circumference of the shielding layer (3) and spaced 90 degrees apart from each other; S5. Providing a sheath extrusion die, wherein the sheath extrusion die comprises an extrusion die core (6) and an extrusion die sleeve (7), wherein the extrusion die core (6) comprises a conical guide portion (61) and a threading portion (62) located at one end of the conical guide portion (61); The extrusion die sleeve (7) is provided with a die cavity (71) suitable for gap fitting with the extrusion die core (6), and a diamond-shaped hole (72) located on the periphery of the threading portion (62) is provided at the end of the die cavity (71); The threading portion (62) includes a shielding layer threading hole (621) and flame retardant rope threading holes (622) located on both sides of the shielding layer threading hole (621); the shielding layer threading hole (621) is suitable for passing the shielding layer (3), and the flame retardant rope threading hole (622) is suitable for passing the flame retardant rope (5); the shielding layer threading hole (621) is a square hole, and the diagonal of the diamond hole (72) coincides with the diagonal of the shielding layer threading hole (621); Adjust the long diagonal of the diamond hole (72) to be in a horizontal state, and adjust the shielding layer (3) with the slot hole (31) so that the center line of the angle formed by two adjacent groups of slot holes (31) is kept coincident with the long diagonal or the short diagonal of the diamond hole (72), and then insert it into the shielding layer threading hole (621), and the gap between the shielding layer threading hole (621) and the shielding layer (3) is 1 to 5 mm; S6, the sheath extrusion die is installed on the extruder head, the sheath material is extruded from the extruder head, flows through the conical guide portion (61), and is extruded from the gap between the extrusion die core (6) and the extrusion die sleeve (7), and at the same time, during the sheath extrusion process, a basalt fiber flame retardant rope (5) is introduced into the flame retardant rope threading hole (622), and the sheath material covers the shielding layer (3) and the flame retardant rope (5), finally forming a sheath layer (4); S7, after the sheath layer (4) is coated, the cable is cooled and shaped to obtain a finished mobile leaky coaxial cable.

9. The method for manufacturing a mobile leaky coaxial cable according to claim 8, characterized in that: The milling tool (82) is driven by a servo motor, with a single tool power of 50 to 500 W, a rotation speed of 50 to 500 rpm, and a tool step speed of 0.1 to 5 mm / s. All the milling tools (82) are started and stopped synchronously and have the same rotation speed through the same servo control system, thereby ensuring the consistency of the processing size of the slot hole (31).

10. The method for manufacturing a mobile leaky coaxial cable according to claim 8, characterized in that: The dimensions of each cutting plane groove (81) are: 50 mm in length and 10 to 40 mm in width; the dimensions of the slot hole (31) are: 10 to 30 mm in length and 3 to 15 mm in width.

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