CN201311794Y

CN201311794Y - Leakage coaxial cable

Info

Publication number: CN201311794Y
Application number: CNU2008202023826U
Authority: CN
Inventors: 寿伟春; 陈宁; 吴欣欣
Original assignee: ZHUHAI HANSEN TECHNOLOGY Co Ltd
Current assignee: ZHUHAI HANSEN TECHNOLOGY Co Ltd
Priority date: 2008-10-24
Filing date: 2008-10-24
Publication date: 2009-09-16
Anticipated expiration: 2018-10-24

Abstract

The utility model relates to a leakage coaxial cable (LCC) which is longitudinally wrapped and has slots. The leakage coaxial cable, from the inside to the outside, sequentially comprises an inner conductor, an insulating inner skin, an insulator, an outer conductor and a protective cover. A plurality of slot groups are uniformly formed on the outer conductor at intervals along the axial direction of the cable, each slot group comprises four slots arranged in a V shape without the joint, in each slot group, the included angle between two parallelly arranged slots and the cable axial line is 165 to175 DEG, and the included angle between the other two parallelly arranged slots and the cable axial line is 5 to 15DEG; and the long edge of each slot has the length of 115 to 130 mm, the short edge of each slot has the length of 3.6 to 5.0 mm, the spacing interval between the two parallelly arranged slots is 110 to 120 mm, and among the slots of each two adjacent slot groups, the spacing interval between the corresponding two slots is 1,420 to 1,440 mm. The leakage coaxial cable provided in the utility model obtains excellent coupling loss and transmission loss at the 450MHz frequency band, so as to improve communication quality.

Description

Leaky coaxial cable

Technical field

The utility model relates to the railway communication field, relates in particular to a kind of leaky coaxial cable of vertical band fluting.

Background technology

Railway speed-raising significantly at present, need information on the way is delivered to train operator, control centre etc. in time, accurately and quickly, this just must realize that the wireless train dispatch system that forms with leaky coaxial cable is the important assurance that improves conevying efficiency and safe driving by the leaky coaxial cable communication system.Because multipath effect and surrounding environment are to the absorption of signal, it is very difficult usually to use common antenna transmitting signal.So people have started the upsurge to leaky coaxial cable research in recent years, because it has significant advantage when transmission signals: low coupling loss, field distribution is stable, and is affected by environment little or the like.At present, though the leaky coaxial cable of different manufacturer production has their own characteristics each, but the technological means of basic principle and employing is roughly the same, leakage coaxial cable has coaxial design, it is made up of a center conductor, a concentric dielectric, an outer conductor and a thermoplastic sheath that is wrapping medium, and characteristic impedance is generally 50 ohm or 75 ohm.The leakage coaxial cable inner wire is generally copper pipe, wrinkle copper pipe or copper facing aluminum steel, with weight reduction.Outer conductor is generally the wrinkle copper pipe, fills dielectric between internal and external conductor, and choosing foamed polyethylene usually is medium, and the material of sheath is generally the black high density polyethylene (HDPE), grey Halogen fire prevention heat shrinkable plastic or black halogen-free fire prevention heat shrinkable plastic.In order to obtain excellent coupling loss and transmission attenuation, very The key factor is that the outer conductor mode of grooving is optimized.The at present external outer conductor mode of grooving of using has five kinds of little pair of Eight characters flute profile formulas, elliptical aperture form, pod form, opening wrinkle belt, rare type of weave, domestic little pair of Eight characters groove commonly used.The spatial coverage of coaxial cable with these line of rabbet joint shapes is less, and cost performance is not high.Little two eight grooves originally are mainly used in suchlike closed domain intervals such as tunnel, colliery and market place builet below the ground, and big pair of octavo slot leakage cable of the present utility model is used for railway communication, in the 450MHz frequency range transmission attenuation little, the coupling loss fluctuation is little.

The utility model content

The purpose of this utility model provides and is used for railway communication, in the 450MHz frequency range transmission attenuation little, the leakage coaxial communication cable that coupling loss fluctuation is little.

For achieving the above object, provide following technical scheme:

Leaky coaxial cable, it comprises inner wire, insulation endothelium, insulation, outer conductor and sheath from inside to outside successively, described outer conductor upper edge cable axis direction evenly has some identical line of rabbet joint groups at interval, each line of rabbet joint group comprises four lines of rabbet joint, described four lines of rabbet joint are two splayeds and arrange, in each line of rabbet joint group, wherein the included angle A of two lines of rabbet joint that are arranged in parallel and cable axis is 165 °～175 °, in addition the axial included angle B of two lines of rabbet joint that are arranged in parallel and cable is 5 °～15 °, included angle A and included angle B complementation; The long limit of each line of rabbet joint is 115～130mm, and minor face is 3.6～5.0mm, and in each line of rabbet joint group, the spacing between two lines of rabbet joint that are arranged in parallel is 110～120mm, and in the two adjacent groups line of rabbet joint, the spacing between corresponding two lines of rabbet joint is 1420～1440mm.

The utility model leaky coaxial cable has changed the fluting form of existing coaxial cable outer conductor, the line of rabbet joint that replaces original form with big two splayed lines of rabbet joint, by to slot structure and optimized dimensions, make cable in the 450MHz frequency range, obtain excellent coupling loss and loss, improved communication quality.

Description of drawings

Fig. 1 is the schematic cross-section of the utility model leaky coaxial cable;

Fig. 2 is the outer conductor structure diagram of the utility model leaky coaxial cable.

Embodiment

Referring to Fig. 1, it is the sectional view of the utility model leaky coaxial cable, this coaxial cable comprises inner wire 1, insulation endothelium (figure does not show), insulating barrier 2, outer conductor 3 and sheath 4 from inside to outside successively, this outer conductor 3 is offered some groups of identical line of rabbet joint groups 5, line of rabbet joint group 5 is big two splayed, concrete group is several different and different according to cable length, and line of rabbet joint spacing is by following spacing setting, and the cable quantity of elongated slot seam group 5 more is many more.Referring to Fig. 2, the line of

rabbet joint

51,52,53,54 has just constituted line of rabbet joint group 5, and the line of rabbet joint the 55, the 56th, in another group line of rabbet joint two.The line of rabbet joint is shaped as rectangle, and its long length of side L3 is 115～130mm, and the long L4 of minor face is 3.6～5.0mm.With a line of rabbet joint group 5 is example, and the included angle A of its two lines of rabbet joint that are arranged in parallel 53,54 and cable axis 10 is 165～175 degree, and in addition the included angle B of two lines of rabbet joint that are arranged in parallel 51,52 and cable axis 10 is 5～15 to spend included angle A and included angle B complementation.In each big two splayed line of rabbet joint group 5, article two, the half-section that the line of rabbet joint that is arranged in parallel is 51,52 is 110～120mm apart from L2, article two, the line of

rabbet joint

51,52 that is arranged in parallel respectively and the spacing L1 of 53,54 of other two lines of rabbet joint that are arranged in parallel be 710～720mm, that is to say, the corresponding line of rabbet joint in the two adjacent line of rabbet joint groups 5 is (as the line of rabbet joint 53 and the line of rabbet joint 55, the line of rabbet joint 54 and the line of rabbet joint 56) spacing is the L1 of twice, i.e. 1420-1440mm.

Why naming the line of rabbet joint on the utility model outer conductor is big two splayeds, mainly is to be used for distinguishing with the little pair of splayed line of rabbet joint of the prior art.Following table is the table of comparisons of the leaky coaxial cable line of rabbet joint size of the big two splayed lines of rabbet joint of medium and small pair of splayed groove of prior art and the utility model and purposes etc.:

The leaky coaxial cable table of comparisons of little pair of splayed groove of table 1 and big two splayed lines of rabbet joint

Project	Little pair of splayed groove	Big two splayed groove
Project	Little pair of splayed groove	Big two splayed groove	The line of rabbet joint and cable axis angle	150～170mm	165～175mm
In addition two lines of rabbet joint and cable axis angle	10°～30°	5°～15°	The line of rabbet joint and cable axis angle	150～170mm	165～175mm
In addition two lines of rabbet joint and cable axis angle	10°～30°	5°～15°	Line of rabbet joint length	25～35mm	115～130mm
Slot width	1.8～3.0mm	3.6～5.0mm	Line of rabbet joint length	25～35mm	115～130mm
Slot width	1.8～3.0mm	3.6～5.0mm	Article two, line of rabbet joint half-section distance is arranged in parallel	40～50mm	110～120mm
Two groups of line of rabbet joint half-section distances	140～150mm	710～720mm		40～50mm	110～120mm
Two groups of line of rabbet joint half-section distances	140～150mm	710～720mm	Application	Subway, tunnel, market place builet below the ground	Railway

The characteristic impedance of above-mentioned leaky coaxial cable is 75 ohm, and its suitable frequency range is 450MHz.

With regard to design, the material of the internal and external conductor of cable, medium and sheath and physical structure and technology thereof have determined the electric property and the physical property of cable, and the slot structure on the leakage coaxial cable outer conductor (line of rabbet joint shape, line of rabbet joint size, arranging density, arrangement mode) has determined the interactive mode of interior electromagnetic energy of cable and external environment condition, thereby will influence the nearly all electricity function index of cable.Leaky cable has three important electric property parameters, promptly uses frequency range, coupling loss and loss.By studies show that, coupling loss axially is cyclic variation along cable, and the slit angle is big more, and coupling loss is more little.This explanation increases after the angle of cracking, and leakage coaxial cable has increased to extraradial energy, and the electric wave coverage in space around can increase.This cable is by to the appropriate design at line of rabbet joint size and angle of inclination, and the coupling loss of the cable that makes is less, and transmission attenuation is little, not if establish repeater less, thereby can reduce investment and be convenient to maintenance, has appreciable economic benefit.According to above-mentioned principle, aforementioned parameters optimum value of the present utility model is: included angle A is 168 °, described included angle B is 12 °, the long limit L3 of each line of rabbet joint is 120mm, minor face L4 is 5.0mm, and in every group of line of rabbet joint, the spacing L2 between two lines of rabbet joint that are arranged in parallel is 120mm, in the two adjacent groups line of rabbet joint, the corresponding groove kerf spacing is 1440mm.

The big two splayed configuration leaky coaxial cables of the utility model are by the improvement to the outer conductor mode of grooving, the appropriate design at line of rabbet joint size and angle of inclination, make this cable in the 450MHz frequency range, have excellent loss and coupling loss, electric property is stable, it is stable, even to produce strong covering, having guaranteed that signal can spread out of and import into uniformly and effectively, guaranteed communication quality, is the excellent leaky coaxial cable of a kind of cost performance.

Above example is the unrestricted the technical solution of the utility model in order to explanation only.Any modification or partial replacement that does not break away from the utility model spirit and scope all should be encompassed in the middle of the claim scope of the present utility model.

Claims

1, leaky coaxial cable, it comprises inner wire, insulation endothelium, insulation, outer conductor and sheath from inside to outside successively, it is characterized in that, described outer conductor upper edge cable axis direction evenly has some identical line of rabbet joint groups at interval, each line of rabbet joint group comprises four lines of rabbet joint, described four lines of rabbet joint are two splayeds and arrange, in each line of rabbet joint group, wherein the included angle A of two lines of rabbet joint that are arranged in parallel and cable axis is 165 °～175 °, in addition the axial included angle B of two lines of rabbet joint that are arranged in parallel and cable is 5 °～15 °, included angle A and included angle B complementation; The long limit of each line of rabbet joint is 115～130mm, and minor face is 3.6～5.0mm, and in each line of rabbet joint group, the spacing between two lines of rabbet joint that are arranged in parallel is 110～120mm, and in the two adjacent groups line of rabbet joint, the spacing between corresponding two lines of rabbet joint is 1420～1440mm.

2, leaky coaxial cable according to claim 1 is characterized in that, the described line of rabbet joint is rectangle.

3, leaky coaxial cable according to claim 2 is characterized in that, described included angle A is 168 °, and described included angle B is 12 °.

4, according to claim 1 or 2 or 3 described leaky coaxial cables, it is characterized in that, the long limit of each line of rabbet joint is 120mm, minor face is 5.0mm, in every group of line of rabbet joint, article two, the spacing between the line of rabbet joint that is arranged in parallel is 120mm, and in the two adjacent groups line of rabbet joint, the spacing between corresponding two lines of rabbet joint is 1440mm.