Coupling Loss Adjustable Leaky Coaxial Cable and Its Usage Method

Abstract

The present invention discloses a leakage coaxial cable with adjustable coupling loss and its usage method, including: an inner conductor, an insulator, an outer conductor, and a sheath. Slots are formed in the outer conductor. A hollow cavity is formed between the sheath and the part of the outer conductor except for the slots. A convex block slidably engaged with the sheath is provided at the center of the hollow cavity. Two metal sheets symmetrically distributed in a V-shape are hinged to the bottom inside the sheath where the convex block is located. The sheath is provided with a convex platform corresponding to the slot part of the outer conductor. The surface of the convex platform facing the slot is curved towards the sheath. The free ends of the two metal sheets are in contact with the bottom edge of the convex block. A plurality of fins are distributed at intervals along the length direction on the upper surfaces of the two metal sheets. The fins are inclined towards the direction deviating from the convex platform. The beneficial effect of the present invention is that by pressing the depth of the convex block extending into the sheath, the area of the slot blocked by the metal sheet can be adjusted, so as to flexibly adjust the coupling loss.

Description

Technical Field

[0001] The present invention relates to the field of communication technologies, and particularly to a leakage coaxial cable with adjustable coupling loss and its usage method. Background Art

[0002] A leakage coaxial cable has the function of signal transmission and also has the function of an antenna. By controlling the openings of the outer conductor, the controlled electromagnetic wave energy can be evenly radiated out and received along the line, realizing the coverage of the electromagnetic field blind area to achieve smooth mobile communication. Its working principle is as follows: The transverse electromagnetic wave is transmitted from the transmitting end to the other end of the cable through the coaxial cable. When the outer conductor of the cable is completely enclosed, the signal transmitted by the cable is completely shielded from the outside, and there is no electromagnetic field outside the cable, or rather, no electromagnetic radiation can be measured. Similarly, the external electromagnetic field will not affect the signal inside the cable. However, through the slots opened on the outer conductor of the coaxial cable, a part of the electromagnetic energy transmitted inside the cable is sent to the external environment. Similarly, external energy can also enter the cable interior. The slots on the outer conductor cause coupling between the electromagnetic field inside the cable and the external electric wave. The specific coupling mechanism depends on the arrangement form of the slots.

[0003] Chinese Utility Model Patent Publication No. CN216055185U discloses a leakage cable and system. The leakage cable includes an inner conductor, an insulating layer, and an outer conductor nested in sequence from the inside out. Multiple rows of slot groups are opened on the outer conductor, and the multiple rows of slot groups are arranged around the outer conductor; among them, the multiple rows of slot groups at least include two rows of slot groups with different slot shapes. By opening multiple rows of slot groups on the outer conductor, there are slot groups with different slot shapes on the same leakage cable. The slot groups with different slot shapes form different electromagnetic wave radiation directions, and are mutually polarization-isolated through different electromagnetic wave radiation directions. While the electromagnetic wave is transmitted along the inner conductor, it radiates electromagnetic waves to the outside through the multiple rows of slot groups opened on the outer conductor, so as to achieve multi-directional coverage of communication signals on the same leakage cable, thereby reducing the construction cost of the leakage cable.

[0004] Chinese Invention Patent Publication No. CN111082193B discloses a low-system-loss radiation-type leakage coaxial cable, which has at least two sequentially arranged slot sections. The leakage cable system loss performance of adjacent slot sections is different, and a transition section is arranged between adjacent slot sections. The leakage cable system loss performance of the transition section is simultaneously close to the leakage cable system loss performance of the adjacent slot sections, improving the signal mutation phenomenon and enhancing the field strength stability. The slot sections and the transition sections on the low-system-loss radiation-type leakage coaxial cable are symmetrically arranged, and the low-system-loss radiation-type leakage coaxial cable does not need to distinguish directions during installation, which is convenient for installation.

[0005] The above patents are all for improving signal problems, but the coupling loss cannot be adjusted as needed after the cable is formed. Summary of the Invention

[0006] The technical problem to be solved by the present invention is that the existing leaky coaxial cable cannot adjust the coupling loss. Therefore, a coupling loss adjustable leaky coaxial cable that can adjust the coupling loss as needed and its usage method are provided.

[0007] The technical solution of the present invention is: a coupling loss adjustable leaky coaxial cable, including: an inner conductor, an insulator, an outer conductor and a sheath. Slots are provided on the outer conductor. A hollow cavity is formed between the sheath and the part of the outer conductor except the slots. A convex block that is slidably matched with the sheath is arranged at the center of the hollow cavity. At the bottom of the convex block located inside the sheath, two metal sheets that are symmetrically distributed in a figure-eight shape are hinged. The sheath is provided with a convex platform corresponding to the slot part of the outer conductor. The surface of the convex platform facing the slot is curved towards the sheath. The free ends of the two metal sheets are in contact with the bottom edge of the convex block. Along the length direction of the upper surfaces of the two metal sheets, a plurality of fins are distributed at intervals. The fins are inclined in a direction deviating from the convex platform.

[0008] An improvement of the above solution is that the bottom of the convex platform is provided with a step, and the height of the step gradually decreases from the edge of the convex platform to the center of the convex platform.

[0009] In the above solution, the fins are made of an elastic material.

[0010] In the above solution, the free ends of the metal sheets are strip-shaped.

[0011] The usage method of the coupling loss adjustable leaky coaxial cable includes the following steps: when it is necessary to adjust the coupling loss, press one or more convex blocks. The two metal sheets hinged to the convex block extend outwards. The free ends of the two metal sheets respectively extend into the upper part of the adjacent slots. The fins are in contact with the bottom of the convex platform above the slots, preventing the metal sheets from retracting.

[0012] The beneficial effect of the present invention is to adjust the area of the slot blocked by the metal sheet by pressing the depth of the convex block extending into the sheath, realizing flexible adjustment of the coupling loss. Brief Description of the Drawings

[0013] Figure 1 It is a schematic diagram of the coupling loss adjustable leaky coaxial cable of the present invention;

[0014] Figure 2 It is a schematic diagram of the usage state of the coupling loss adjustable leaky coaxial cable of the present invention;

[0015] In the figure, 1, inner conductor; 2, insulator; 3, outer conductor; 4, sheath; 5, slot; 6, hollow cavity; 7, convex block; 8, metal sheet; 9, convex platform; 10, fin. Embodiment

[0016] The technical solutions in the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0017] As shown in Figure 1 the figure, the coupling loss adjustable leaky coaxial cable includes: an inner conductor 1, an insulator 2, an outer conductor 3, and a sheath 4. A slot 5 is formed on the outer conductor. A hollow cavity 6 is formed between the sheath and the part of the outer conductor except the slot. A convex block 7 slidably engaged with the sheath is provided at the center of the hollow cavity. Two metal sheets 8 symmetrically distributed in an eight-character shape are hinged at the bottom of the convex block located inside the sheath. A convex platform 9 is provided on the sheath corresponding to the slot part of the outer conductor. The surface of the convex platform facing the slot is curved towards the sheath. The free ends of the two metal sheets are in contact with the bottom edge of the convex block. A plurality of fins 10 are distributed at intervals along the length direction on the upper surfaces of the two metal sheets. The fins are inclined in a direction deviating from the convex platform.

[0018] As an embodiment of the present invention, three rows of slots are formed on the radial surface of the outer conductor. The specific shape of the slots can be strip-shaped, circular, etc. The material of the convex block can be the same as that of the sheath. The shape of the free end of the metal sheet should at least be able to block part of the slot. The fins are preferably made of elastic material to prevent breakage when being squeezed against the bottom of the convex platform.

[0019] As a preferred example of the present invention, a step is provided at the bottom of the convex platform. The height of the step gradually decreases from the edge of the convex platform to the center of the convex platform. The function of the step is to prevent the fins from retracting. That is to say, the sliding direction of the fins in the present invention is unidirectional, and can only gradually increase the shielding area above the corresponding slot, and cannot return to the initial position.

[0020] In the present invention, the free ends of the metal sheets can be in various forms, such as strip-shaped, circular or other possible shapes.

[0021] As shown in Figure 2 the figure, the usage method of the coupling loss adjustable leaky coaxial cable includes the following steps: when it is necessary to adjust the coupling loss, press a convex block. The two metal sheets hinged to the convex block extend outwards. The free ends of the two metal sheets respectively extend into the upper part of the adjacent slots. The fins are in contact with the bottom of the convex platform above the slots, preventing the metal sheets from retracting. At this time, if it is necessary to continue with the slots in other columns, the corresponding convex block can be pressed and the previous operation can be repeated.

[0022] The idea of the present invention is to unidirectionally adjust the coupling loss of the slots in a converging manner, with simple and flexible operation.

Claims

1. Coupling loss adjustable leaky coaxial cable, comprising: Inner conductor (1), insulator (2), outer conductor (3) and sheath (4), with slots (5) provided on the outer conductor, characterized in that: a hollow cavity (6) is formed between the sheath and the part of the outer conductor except the slots, a convex block (7) slidably engaged with the sheath is provided at the center of the hollow cavity, two metal sheets (8) symmetrically distributed in a figure-eight shape are hinged to the bottom inside the sheath of the convex block, a convex platform (9) is provided on the sheath corresponding to the slot part of the outer conductor, the surface of the convex platform facing the slot is curved towards the sheath, the free ends of the two metal sheets are in contact with the bottom edge of the convex platform, a plurality of fins (10) are spaced along the length direction on the upper surfaces of the two metal sheets, and the fins are inclined in a direction deviating from the convex platform.

2. The adjustable coupling loss leaky coaxial cable according to claim 1, wherein: A step is provided at the bottom of the convex platform, and the height of the step gradually decreases from the edge of the convex platform to the center of the convex platform.

3. The adjustable coupling loss leaky coaxial cable according to claim 1, characterized in that: The fins are made of an elastic material.

4. The adjustable coupling loss leaky coaxial cable according to claim 1, characterized in that: The free ends of the metal sheets are strip-shaped.

5. The method for using a leakage coaxial cable with adjustable coupling loss according to any one of claims 1-4, characterized in that: Comprising the following steps: When it is necessary to adjust the coupling loss, press one or more convex blocks, the two metal sheets hinged to the convex blocks extend outwards, the free ends of the two metal sheets respectively extend above the adjacent slots, the fins contact the bottom of the convex platform above the slots, preventing the metal sheets from retracting.

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