阅读说明：本技术 一种宽高频漏缆 (Wide high-frequency leaky cable ) 是由 杨志行 刘中华 卫伟 吕岑佳 于 2019-08-20 设计创作，主要内容包括：本发明提供了一种宽高频漏缆,包括由内向外依次同轴嵌套的内导体1、绝缘层2、外导体3以及护套4,所述外导体3沿轴向开设以节距P为周期排列的多个槽孔组5；所述槽孔组5包括沿轴向错位重叠排列的多个阵列组6；所述阵列组6包括左阵列7和右阵列8,所述左阵列7和右阵列8呈“八”字形沿轴线排列,且相对于轴线的倾角互补；所述左阵列7和右阵列8沿二者连线的中垂线对称；所述左阵列7和右阵列8中心之间的距离为P/2。本发明提增加了低频的辐射性能和高频的传输性能,以250m的综合损耗评估,将使用频段内综合损耗差异控制在5dB内,从而使得其更适合在2G/3G/4G/5G合路中使用。(The invention provides a wide high-frequency leaky cable which comprises an inner conductor 1, an insulating layer 2, an outer conductor 3 and a sheath 4 which are coaxially nested from inside to outside in sequence, wherein the outer conductor 3 is provided with a plurality of slot hole groups 5 which are arranged periodically by taking a pitch P as an axial direction; the slotted hole group 5 comprises a plurality of array groups 6 which are staggered and overlapped along the axial direction; the array group 6 comprises a left array 7 and a right array 8, the left array 7 and the right array 8 are arranged along the axis in a splayed shape, and the inclination angles of the left array 7 and the right array 8 relative to the axis are complementary; the left array 7 and the right array 8 are symmetrical along a perpendicular bisector of a connecting line of the left array and the right array; the distance between the centers of the left array 7 and the right array 8 is P/2. The invention increases the low-frequency radiation performance and the high-frequency transmission performance, and controls the difference of the comprehensive loss in the used frequency band within 5dB according to the comprehensive loss evaluation of 250m, thereby being more suitable for being used in a 2G/3G/4G/5G combiner.)

1. A wide high-frequency leaky cable is characterized by comprising an inner conductor (1), an insulating layer (2), an outer conductor (3) and a sheath (4) which are coaxially nested from inside to outside in sequence,

the outer conductor (3) is provided with a plurality of slot hole groups (5) which are arranged by taking a pitch P as a period along the axial direction;

the slotted hole group (5) comprises a plurality of array groups (6) which are staggered and overlapped along the axial direction;

the array group (6) comprises a left array (7) and a right array (8), the left array (7) and the right array (8) are arranged along an axis in a splayed shape, and the inclination angles of the left array and the right array are complementary relative to the axis;

the left array (7) and the right array (8) are symmetrical along a perpendicular bisector of a connecting line of the left array and the right array;

the distance between the centers of the left array (7) and the right array (8) is P/2;

the left array (7) comprises an upper left slotted hole (71) and a lower left slotted hole (72) which are arranged along the inclination angle direction of the left array (7), the upper left slotted hole (71) and the lower left slotted hole (72) extend along the inclination angle direction of the left array (7) in length, the lower long side of the upper left slotted hole (71) and the upper long side of the lower left slotted hole (72) are positioned on the same straight line, or the upper long side of the upper left slotted hole (71) and the lower long side of the lower left slotted hole (72) are positioned on the same straight line;

the right array (8) comprises an upper right slotted hole (81) and a lower right slotted hole (82) which are arranged along the inclination angle direction of the right array (8), the upper right slotted hole (81) and the lower right slotted hole (82) extend along the inclination angle direction of the right array (8) in length, the lower long edge of the upper right slotted hole (81) and the upper long edge of the lower right slotted hole (82) are positioned on the same straight line, or the upper long edge of the upper right slotted hole (81) and the lower long edge of the lower right slotted hole (82) are positioned on the same straight line.

2. The leaky cable as claimed in claim 1, wherein P is in a range of 200-250 mm.

3. Leaky cable as claimed in claim 1, characterized in that said upper left slot (71) and said lower left slot (72) are structurally identical in size and are centrally symmetrical with respect to a point on the outer conductor (3).

4. Leaky cable as claimed in claim 1, characterized in that said left array (7) is inclined at an angle of 15 ° to 30 ° with respect to the axis.

5. Leaky cable according to claim 1, characterized in that said slot groups (5) comprise four array groups (6) which are staggered and overlapped in sequence along the axial direction, namely a first array group (61), a second array group (62), a third array group (63) and a fourth array group (64),

the distance between the first array group (61) and the center point of the second array group (62) is D1;

the distance between the second array group (62) and the center point of the third array group (63) is D2;

the distance between the third array group (63) and the center point of the fourth array group (64) is D3;

the distance between the left array of the fourth array group (64) and the center point of the right array of the first array group (61) is D4;

wherein D1, D2, D3, D4, P/4;

or D1-D3-P/10, D2-P/15 and D4-7-P/30.

6. Leaky cable as claimed in claim 5,

the left array of the first array group (61) forms an included angle alpha 1 with the axis;

the left array of the second array group (62) forms an included angle alpha 2 with the axis;

the included angle between the left array of the third array group (63) and the axis is alpha 3;

the left array of the fourth array group (64) forms an included angle alpha 4 with the axis;

wherein the content of the first and second substances,

α1＝α2＝α3＝α4；

or α 1 ═ α 3 and α 2 ═ α 4.

7. Leaky cable according to claim 5, characterized in that the shape and size of the slots in said first array group (61) are the same as the shape and size of the slots in said third array group (63);

the second array set (62) slots are the same shape and size as the fourth array set (64) slots.

8. Leaky cable according to claim 1, characterized in that the slots in said left (7) and right (8) arrays have a length in the range of 10-20 mm and a width in the range of 2-4 mm.

9. Leaky cable as claimed in claim 1, characterized in that said left array (7) and said right array (8) have a length in the range of 20mm to 40 mm;

the distance between the upper left slotted hole (71) and the lower left slotted hole (72) in the left array (7) ranges from 0mm to 10 mm.

10. Leaky cable according to claim 1, characterized in that the shape of the slots in said set of slots (5) is selected from any of the following: rectangular, diamond, oval.

Technical Field

The invention relates to the technical field of radio frequency coaxial cables, in particular to a 5G wide high frequency special-shaped splayed groove leaky coaxial cable.

Background

The tunnel mainly includes highway tunnel, railway tunnel, subway tunnel etc. is the important scene in the mobile communication network deployment, because tunnel structure seals, is the banding distribution along the line, and different tunnels have different shape structure, horizontal size, and its construction material, composition, proportion are also different, and these all can produce the influence of different degrees to wireless signal's reflection, absorption, receive the influence of factors such as different automobile bodies, tunnel horizontal size, electromagnetic environment simultaneously, the loss that the signal pierces through the automobile body also can have the difference. Tunnel scene coverage also becomes a difficulty of mobile communication network coverage.

The leaky coaxial cable is a special coaxial cable with dual functions of a transmission line and an antenna, can be laid along the wall in the tunnel and can be bent along with the tunnel, and wireless signals can be uniformly released in the tunnel without being influenced by factors such as the shape, the bending and the gradient of the tunnel, so that the leaky coaxial cable is the best choice for wireless coverage of the tunnel scene at present.

The traditional radiation type leaky coaxial cable does not support the application of a 5G system, and the novel leaky coaxial cable suitable for 5G is difficult to consider the performance of each frequency band of 800-3600MHz so as to meet the large-span combining application of the frequency bands of the system. At present, the leaky cable applicable to the 5G is either a special leaky cable developed for the 5G dedicated frequency by compromising the 2G (CDMA 800& GSM900) in system selection, or a pseudo-full frequency leaky cable which satisfies the 2G, 3G, 4G, and 5G coverage at the cost of a greatly low device coverage radius, which brings a huge challenge to the determination of the 5G tunnel coverage scheme and the co-construction sharing design of the 5G.

If a leaky cable is used for 2G, 3G, 4G and 5G, the bearing frequency ranges of 2G, 3G, 4G and 5G need to be considered, the use frequency range needs to cover 800-3600MHz, the use frequency needs to span more than 2800MHz, the span difference of the electromagnetic wave wavelength needs to be more than 4.5 times, and the electromagnetic wave radiation amount of each frequency needs to be balanced.

The prior patent CN201310090200.6 discloses a leaky coaxial cable, which is a wide, high frequency, low loss, uniform radiation leaky coaxial cable, and sequentially comprises an inner conductor, an insulating layer, an outer conductor and a sheath from inside to outside, wherein a plurality of identical slot groups are uniformly arranged on the outer conductor at intervals along the axial direction of the cable, and the corresponding slots in the slot groups are arranged in a splayed shape; each slot group comprises a first slot group and a second slot group which are adjacent, the first slot group comprises 8 identical first slots, the second slot group comprises 8 identical second slots, and the length of the first slot is greater than that of the second slot. By designing 2 groups of four-splayed slot holes with the same pitch and different slot hole lengths, the coupling loss and the attenuation performance of the leakage cable in the 800-2700MHZ frequency band are in a more uniform and more ideal range.

Although the conventional patent CN201310090200.6 solves some problems, it is a problem to be solved urgently to realize that 2G, 3G, 4G, and 5G share one leaky cable and provide a better leaky cable specially designed for wideband and high frequency optimization.

Disclosure of Invention

The invention aims to solve the problem of providing a leaky cable, which has the following characteristics: the using frequency band meets the range of 800 MHz-3600 MHz, the radiation performance of each frequency band is uniform and stable, the coupling loss fluctuation is small, the transmission performance and the radiation performance in the using frequency band can be balanced, the comprehensive loss phase difference is controlled within 5dB in practical application, and the unification of the disconnection of 2G/3G/4G/5G leaky cables is facilitated.

In order to solve the problems, the invention provides a wide high-frequency leaky cable which comprises an inner conductor 1, an insulating layer 2, an outer conductor 3 and a sheath 4 which are coaxially nested from inside to outside in sequence, wherein the outer conductor 3 is provided with a plurality of slot hole groups 5 which are arranged by taking a pitch P as a cycle along the axial direction; the slotted hole group 5 comprises a plurality of array groups 6 which are staggered and overlapped along the axial direction; the array group 6 comprises a left array 7 and a right array 8, the left array 7 and the right array 8 are arranged along the axis in a splayed shape, and the inclination angles of the left array 7 and the right array 8 relative to the axis are complementary; the left array 7 and the right array 8 are symmetrical along a perpendicular bisector of a connecting line of the left array and the right array; the distance between the centers of the left array 7 and the right array 8 is P/2; the left array 7 comprises a left upper slotted hole 71 and a left lower slotted hole 72 which are arranged along the inclination angle direction of the left array 7, the left upper slotted hole 71 and the left lower slotted hole 72 extend along the inclination angle direction of the left array 7 in length, the lower long edge of the left upper slotted hole 71 and the upper long edge of the left lower slotted hole 72 are positioned on the same straight line, or the upper long edge of the left upper slotted hole 71 and the lower long edge of the left lower slotted hole 72 are positioned on the same straight line; the right array 8 includes a right upper slot 81 and a right lower slot 82 arranged along the inclination angle direction of the right array 8, the right upper slot 81 and the right lower slot 82 extend in length along the inclination angle direction of the right array 8, the lower long side of the right upper slot 81 and the upper long side of the right lower slot 82 are located on the same straight line, or the upper long side of the right upper slot 81 and the lower long side of the right lower slot 82 are located on the same straight line.

According to one embodiment of the present invention, the lowest point of the upper left slot 71 is higher than the highest point of the lower left slot 72, or the lowest point of the upper left slot 71 and the highest point of the lower left slot 72 are the same; the lowest point of the right upper slot hole 81 is higher than the highest point of the right lower slot hole 82, or the lowest point of the right upper slot hole 81 and the highest point of the right lower slot hole 82 are in the same point.

According to one embodiment of the invention, P is in the range of 200-250 mm.

According to one embodiment of the present invention, the upper left slot 71 and the lower left slot 72 are identical in structure size and are symmetrical with respect to a point on the outer conductor 3.

According to one embodiment of the invention, the left array 7 is inclined at an angle of 15 ° to 30 ° with respect to the axis.

According to one embodiment of the present invention, the slot group 5 includes four array groups 6, namely a first array group 61, a second array group 62, a third array group 63 and a fourth array group 64, which are sequentially arranged in an axially staggered and overlapped manner, wherein the distance between the center points of the first array group 61 and the second array group 62 is D1; the distance between the second array group 62 and the center point of the third array group 63 is D2; the distance between the third array group 63 and the center point of the fourth array group 64 is D3; the distance between the center point of the left array 7 of the fourth array group 64 and the center point of the right array 8 of the first array group 61 is D4; wherein D1, D2, D3, D4, P/4; or D1-D3-P/10, D2-P/15 and D4-7-P/30.

According to one embodiment of the present invention, the left array 7 of the first array group 61 has an angle α 1 with the axis; the included angle between the left array 7 of the second array group 62 and the axis is alpha 2; the included angle between the left array 7 of the third array group 63 and the axis is alpha 3; the included angle between the left array 7 of the fourth array group 64 and the axis is alpha 4; wherein α 1 ═ α 2 ═ α 3 ═ α 4; or α 1 ═ α 3 and α 2 ═ α 4.

According to an embodiment of the present invention, the shape and size of the slots in the first array group 61 are the same as the shape and size of the slots in the third array group 63; the second array set 62 slots are the same shape and size as the fourth array set 64 slots.

According to one embodiment of the invention, the slots in the left and right arrays 7, 8 have a length in the range of 10mm to 20mm and a width in the range of 2mm to 4 mm.

According to one embodiment of the invention, the length of the left array 7 and the right array 8 ranges from 20mm to 40 mm; the distance between the upper left slot 71 and the lower left slot 72 in the left array 7 ranges from 0mm to 10 mm.

According to an embodiment of the present invention, the shape of the slots in the set of slots 5 is selected from any one of the following: rectangular, diamond, oval.

The invention not only meets the lower limit of the slot length required by low-frequency (800MHz) radiation, but also avoids the upper limit of the slot length limited by the highest using frequency band (3700MHz), successfully enhances the low-frequency radiation performance, weakens the influence of the overlong slot length on the high-frequency transmission performance, and balances the radiation characteristic and the transmission characteristic of the whole leaky cable. The invention increases the low-frequency radiation performance and the high-frequency transmission performance, and controls the difference of the comprehensive loss in the used frequency band within 5dB according to the comprehensive loss evaluation of 250m, thereby being more suitable for being used in a 2G/3G/4G/5G combiner.

Drawings

FIG. 1 is a schematic view of a wide high frequency leaky cable;

FIG. 2 is a schematic diagram of a slot group and an array group;

FIG. 3 is a schematic illustration of a left array and a right array;

FIG. 4 is a schematic diagram of two configurations of the left array;

FIG. 5 is a schematic diagram of a slot cluster comprising four array clusters; and

FIG. 6 is a schematic illustration of tilt angles of an array.

Detailed Description

In the following detailed description of the preferred embodiments of the invention, reference is made to the accompanying drawings that form a part hereof, and in which is shown by way of illustration, specific features of the invention, such that the advantages and features of the invention may be more readily understood and appreciated. The following description is an embodiment of the claimed invention, and other embodiments related to the claims not specifically described also fall within the scope of the claims.

Fig. 1 shows a schematic view of a wide high frequency leaky cable.

As shown in fig. 1, the wide high-frequency leaky cable comprises an inner conductor 1, an insulating layer 2, an outer conductor 3 and a sheath 4 which are coaxially nested from inside to outside in sequence, wherein the outer conductor 3 is provided with a plurality of slot groups 5 which are arranged in a periodic manner by taking a pitch P as an axial direction.

Radio frequency energy is longitudinally transmitted from one end of the inner conductor 1 to the other end, the outer conductor 3 provides transverse shielding, a slotted hole is formed in the outer conductor 3, an electromagnetic field is diffracted through the slotted hole, the electromagnetic field on the outer side of the outer conductor 3 of the leaky cable is excited, the radio frequency energy is radiated from the slotted hole, and the purposes of outward transmission and external electromagnetic wave receiving are achieved.

The slot group 5 is a combination of a plurality of slots periodically arranged on the outer conductor 3, and the arrangement and arrangement form of the slots have direct correlation with the frequency band of the electromagnetic wave. The distance between two adjacent slot groups 5 is set as P, and the selection of the value of P is carried out according to the range of P suitable for a wider electromagnetic wave frequency range and is 200-250 mm.

FIG. 2 shows a schematic diagram of a slot array and an array.

As shown in fig. 2, the slot hole group 5 includes a plurality of array groups 6 arranged in an axially staggered overlapping manner; the array group 6 comprises a left array 7 and a right array 8, the left array 7 and the right array 8 are arranged along the axis in a splayed shape, and the inclination angles of the left array 7 and the right array 8 relative to the axis are complementary; the left array 7 and the right array 8 are symmetrical along a perpendicular bisector of a connecting line of the left array and the right array; the distance between the centers of the left array 7 and the right array 8 is P/2.

The array groups 6 are basic constituent units of the slot group 5, and each array group 6 is translated along the axial direction of the drain cable by a certain distance and is overlapped with another array group 6. The distance between two adjacent arrays such that the harmonic suppression principle is followed between the left 7 of the adjacent arrays; while the adjacent right array 8 also follows the principle of harmonic suppression.

The array group 6 comprises two parts, namely a left array 7 and a right array 8, wherein the left array 7 and the right array 8 are distributed in a splayed manner, the distance is P/2, and according to the frequency characteristic of a four-splayed structure, the lower limit frequency band of radiation is

The applicable frequency band of the four-eight structure is f-7 f. Where c is the speed of light and ε is the equivalent relative permittivity of the cable. In the invention, a plurality of array groups 6 cover a plurality of frequency bands, so that the radiation frequency band of electromagnetic signals is widened.

In the invention, the array group 6 adopts an eight-shaped structure, for example, the left array 7 is in a '/' shape, the right array 8 is in a '\\' shape, so that even harmonics of-2 and-4 orders and the like are mutually suppressed by '/' ('\ ") and'/'(') are mutually suppressed by-3 or-5 orders, the radiation of signals in a used frequency band is more uniform, and the coupling loss fluctuation is reduced.

Fig. 3 shows a schematic of the left and right arrays.

As shown in fig. 3, the left array 7 includes an upper left slot 71 and a lower left slot 72 arranged along the inclination direction of the left array 7, the upper left slot 71 and the lower left slot 72 extend in length along the inclination direction of the left array 7, the lower long side of the upper left slot 71 and the upper long side of the lower left slot 72 are located on the same straight line, or the upper long side of the upper left slot 71 and the lower long side of the lower left slot 72 are located on the same straight line; the right array 8 includes a right upper slot 81 and a right lower slot 82 arranged along the inclination angle direction of the right array 8, the right upper slot 81 and the right lower slot 82 extend in length along the inclination angle direction of the right array 8, the lower long side of the right upper slot 81 and the upper long side of the right lower slot 82 are located on the same straight line, or the upper long side of the right upper slot 81 and the lower long side of the right lower slot 82 are located on the same straight line.

In the present embodiment, the slot is illustrated as a rectangle, and the slot may be in other forms of the present invention or the future invention.

Taking the left array 7 as an example, on the basis of suppressing odd harmonics by arranging the slots left and right, the-3 th harmonic radiated by the other side is further suppressed between the upper left slot 71 and the lower left slot 72 in the invention, so that the radiation of signals in a use frequency band is more uniform, and the coupling loss fluctuation is reduced. Meanwhile, compared with the mode of forming a single slotted hole in the prior art, the combination mode of the left array 7 divides a complete rectangular groove into two parts, and then through displacement in a specific mode, meets the lower limit of the groove length required by low-frequency (800MHz) radiation, avoids the upper limit of the groove length limited by the highest using frequency band (3700MHz), successfully enhances the low-frequency radiation performance, weakens the influence of overlong groove length on the high-frequency transmission performance, and balances the radiation characteristic and the transmission characteristic of the whole leaky cable.

Fig. 4 shows a schematic diagram of two configurations of the left array.

As shown in FIG. 4, the lower long side of the left upper slot 71 and the upper long side of the left lower slot 72 are located on the same straight line, or the upper long side of the left upper slot 71 and the lower long side of the left lower slot 72 are located on the same straight line.

In the present invention, there is at most one intersection point between the upper left slot 71 and the lower left slot 72. When the slot is rectangular, it is preferable that the lower long side of the left upper slot 71 and the upper long side of the left lower slot 72 are located on the same straight line. The arrangement of the upper and lower slotted holes further inhibits-3 harmonic waves on the basis of mutually inhibiting-3 harmonic waves and-5 harmonic waves between two transversely adjacent slotted holes, so that the signal radiation is more uniform in size, the radiation field is more stable, and the coupling loss fluctuation is small.

In addition, the two forms of staggered arrangement of the upper and lower slotted holes of the invention enable the processing of the outer conductor 3 to be simple, and the slotted holes are easy to keep the original shape when the outer conductor 3 is longitudinally wrapped.

According to one embodiment of the invention, P is in the range of 200-250 mm.

In the invention, taking the slot group 5 comprising four array groups 6 as an example, the slot groups are arranged in a vertical 'eight' shape, so that 16 radiation units are contained in one period of the slot group 5, compared with 8 radiation units of a traditional four-eight structure, the number of the radiation units is doubled, meanwhile, in order to radiate electromagnetic signals in the frequency band of 800-3600MHz, according to the frequency characteristic of the four-eight structure, the radiation frequency band is f1-7f1,

where c is the speed of light and ε is the equivalent relative permittivity of the cable. When P is 190mm, the radiation frequency band is 745-5215 MHz according to the calculation of epsilon 1.248, and when P is 260mm, the radiation frequency band is 540-3820 MHz, namely 190-260 mm can meet the radiation requirement. However, the radiation type leaky cable has resonant frequency and unavailable frequency, and needs to be designed in non-civil communication frequency bands (960-1710 MHz, 2025-2110 MHz, 2170-2300 MHz, 2400-2515 MHz and 2675-3300 MHz). Meanwhile, for balancing the radiation performance of high and low frequencies, if epsilon is limited to 1.2-1.29, the value range of P can be divided into three sections, namely 190-196 mm&215～221&235～245mm。

According to one embodiment of the present invention, the upper left slot 71 and the lower left slot 72 are identical in structure size and are symmetrical with respect to a point on the outer conductor 3.

The upper left slot 71 and the lower left slot 72 are symmetrical with respect to a certain point, which means that the upper left slot and the lower left slot are coincident with each other when rotated 180 degrees along the midpoint of the connecting line of the center lines of the upper left slot and the lower left slot. The effect of this on-3 harmonic suppression is better due to the consistent dimensions of the structures and the relative positioning in the present invention.

Since the right array 8 is arranged symmetrically to the left array 7, the invention is illustrated only with the left array 7, having the same or similar structure in the right array 8, the function of which is the same.

According to one embodiment of the invention, the left array 7 is inclined at an angle of 15 ° to 30 ° with respect to the axis.

The invention takes the structural size of 5/4' coaxial cable as an example, and the inclination angle between 15 DEG and 30 DEG is the balance interval of the transmission performance, the radiation performance and the broadband performance of the special-shaped splayed slot structure. The angle is preferably between 15 and 30 degrees, the coverage range of 800-3600MHz can be better met, and the radiation performance of each frequency band is uniform and stable.

FIG. 5 shows a schematic diagram of a slot cluster comprising four array clusters.

As shown in fig. 5, the slot group 5 includes four array groups 6, namely a first array group 61, a second array group 62, a third array group 63, and a fourth array group 64, which are sequentially arranged in an axially staggered and overlapping manner, and the distance between the center points of the first array group 61 and the second array group 62 is D1; the distance between the second array group 62 and the center point of the third array group 63 is D2; the distance between the third array group 63 and the center point of the fourth array group 64 is D3; the distance between the left array of the fourth array group 64 and the center point of the right array of the first array group 61 is D4; wherein D1, D2, D3, D4, P/4; or D1-D3-P/10, D2-P/15 and D4-7-P/30.

The staggered overlapping along the axial direction means that the first array group 61 to the fourth array group 64 are sequentially arranged along the axial direction, and the left arrays of the second array group to the fourth array group are positioned between the left array and the right array of the first array group; the left arrays of the third array group and the fourth array group and the right arrays of the first array group are positioned between the left arrays and the right arrays of the second array group; the left array of the fourth array group, the right array of the first array group and the right array of the second array group are positioned between the left array and the right array of the third array group; the right array of the first array group to the third array group is positioned between the left array and the right array of the fourth array group. The distance between the center points of the right array of the first array group 61 and the left array of the fourth array group 64 is D4.

Since the relative position between the left and right arrays in the array set is fixed, the distance between the centers of the adjacent array sets 6 is equal to the distance between the centers of the adjacent left arrays in fig. 5.

In the invention, the scheme that D1 is D2, P3 is P/12, and D4 is P/4 is adopted; alternatively, the approach of D1 ═ D3 ═ P/10, D2 ═ P/15, and D4 ═ 7 ═ P/30 was used such that the left array 7 of each "/" shape within the groove group was aligned with the laterally adjacent left array 7 of the "/" shape following the harmonic suppression principle, while the right array 8 of each "\\" shape was aligned with the laterally adjacent right array 8 following the harmonic suppression principle.

The invention mainly adopts a method of shifting the waveform by half period (namely 1/2 wavelength) and suppressing higher harmonics by a phase difference of pi.

Namely, a series of new gaps (m is-3, -5, -7 ….) are arranged at a distance P/2m beside the original gap to suppress the m-th higher harmonics. For the splayed structure leakage cable, the symmetrical design can effectively inhibit the generation of even harmonics, so that-3 harmonics are main interference sources, and the novel slotted holes are formed at the positions of P/6 of the original slotted holes, so that-3 harmonics can be effectively inhibited.

Through research, the invention provides two schemes for designing the four-splayed groove: the first is to continue to suppress the-5 th harmonic, i.e. to continue to open the holes at the original slot distance P/10, which is an unequal distance arrangement. The second is to form another slot between two slots that mutually suppress the-3 th harmonic, i.e. the distance is P/6/2, and the newly added slots also need to suppress the-3 rd harmonic, i.e. they are arranged equidistantly.

When the distance is equal, D1, D2, D3, D4 and P/4 are equal; in the use frequency band, the optimization of the target frequency band focuses on the middle-low frequency performance of the frequency band at the central frequency and the lower part of the frequency band. For example, the frequency band is 800-3600MHz, and the intermediate frequency optimization focuses on the 1700-2200 MHz frequency band.

When the distance is not equal, D1 is D3 is P/10, D2 is P/15, D4 is 7 is P/30, and the optimization of the target frequency band is focused on the medium-high frequency performance in the central frequency and the partial frequency bands above the central frequency. For example, the frequency band is 800-3600MHz, and the intermediate frequency optimization focuses on the 2200-2700 MHz frequency band.

FIG. 6 shows a schematic diagram of tilt angles of an array set.

As shown in fig. 6, the left array of the first array group 61 forms an angle α 1 with the axis; the left array of the second array group 62 forms an included angle alpha 2 with the axis; the included angle between the left array of the third array group 63 and the axis is alpha 3; the left array of the fourth array group 64 forms an angle α 4 with the axis; wherein α 1 ═ α 2 ═ α 3 ═ α 4; or α 1 ═ α 3 and α 2 ═ α 4.

In an included angle between the left array and the axis of the first array to the fourth array, when α 1 is α 2, α 3 is α 4, if the sizes of the slots are completely the same, the radiation capabilities of all the radiation units are the same. Since-3 harmonics (a main interference source of the radial radio frequency coaxial cable) are mutually suppressed between the left array of the first array group 61 and the left array of the third array group 63, and between the left array of the second array group 62 and the left array of the fourth array group 64, it is beneficial to reduce harmonic interference when α 1 is α 3 and α 2 is α 4. And-5 harmonics are mutually suppressed between the left array of the first array group 61 and the left array of the second array group 62, and between the left array of the third array group 63 and the left array of the fourth array group 64, and the interference ratio of the-5 harmonics is relatively small, and the influence degree on the whole radiation field is low, so that the occurrence of α 1 ≠ α 2 and α 2 ≠ α 4 is allowed, which is beneficial to greatly increase the flexibility of controlling the radiation quantity at the expense of certain stability, or in other words: the design of the slot hole can be made to have performance characteristics and frequency band purpose.

According to an embodiment of the present invention, the shape and size of the slots in the first array group 61 are the same as the shape and size of the slots in the third array group 63; the second array set 62 slots are the same shape and size as the fourth array set 64 slots.

According to one embodiment of the invention, the slots in the left and right arrays have a length in the range of 10mm to 20mm and a width in the range of 2mm to 4 mm. The length range of the left array 7 and the right array 8 is 20mm-40 mm; the distance between the upper left slot 71 and the lower left slot 72 in the left array 7 ranges from 0mm to 10 mm.

When the slot is rectangular, the length of the slot needs to satisfy L < lambda/4, and lambda is the designed highest use frequency. For example, in the present invention, the maximum frequency of use is 3700MHz, and L is satisfied to be L < 20.27mm, and L ∈ [10mm, 20mm ], W ∈ [2mm, 4mm ] are preferable in the present invention.

Assuming that the slot length is L, the total length of the combination of the "/" shaped upper left slot 71 in each left array 7 and the corresponding "/" shaped lower left slot group 5 is L α ═ 2 × L + B, where L is the slot length, B is the distance between the upper left slot 71 and the lower left slot 72 in the direction of the inclination angle of the left array 7, α is the inclination angle of the left array 7, and α e [15 °, 30 ° ], then L α should satisfy:

wherein R denotes the outer conductor 3 equivalent radius;

in the present invention, L.alpha. [20mm, 40mm ], B.alpha. [0mm, 10mm ].

According to an embodiment of the present invention, the shape of the slots in the set of slots 5 is selected from any one of the following: rectangular, diamond, oval.

Each slotted hole can be finely adjusted in shape, for example, four corners of a rectangle are led to form round corners or two corners on the outer side are led to form round corners, the diameter of a circle of each lead corner is W, punching die abrasion is not easily caused when a die is used for punching holes after the lead corners, the outer conductor 3 is easy to form when wrapped longitudinally, and the wrapping sheath 4 is not easily deformed after forming.

In the invention, the splayed slot groups are arranged in an up-and-down splayed manner, and 16 radiation units are contained in one period slot group 5, so that the number of the radiation units is doubled compared with the number of 8 radiation units in the traditional four-splayed structure.

In the invention, the arrangement mode of the upper and lower eight-shaped slotted holes is that a plurality of '/' shaped slotted holes in the left array 7 mutually inhibit-3 th harmonic waves and-5 th harmonic waves, and a plurality of (' \\ ") shaped slotted holes in the right array 8 mutually inhibit-3 th harmonic waves and-5 th harmonic waves; the "/" shaped slots in the left array 7 and the "\" shaped slots in the right array 8 suppress the-2 and-4 harmonics from each other; meanwhile, the upper left slot 71 and the lower left slot 72 of the left array 7 further suppress the-3 th harmonic of the radiation from each other, and the upper right slot 81 and the lower right slot 82 of the right array 8 further suppress the-3 rd harmonic of the radiation from each other. The structure in the invention enables the radiation of signals in the use frequency band to be more uniform and reduces the coupling loss fluctuation.

In the invention, the slotted holes in the left array and the right array are separately arranged and are arranged in a staggered manner according to a specific mode, so that the lower limit of the slot length of the low-frequency (800MHz) radiation requirement is met, the upper limit of the slot length limited by the highest using frequency band (3700MHz) is avoided, the low-frequency radiation performance is successfully enhanced, the influence on the high-frequency transmission performance due to the overlong slot length is weakened, and the radiation characteristic and the transmission characteristic of the whole leaky cable are balanced. The invention increases the low-frequency radiation performance and the high-frequency transmission performance, and controls the difference of the comprehensive loss in the used frequency band within 5dB according to the comprehensive loss evaluation of 250m, thereby being more suitable for being used in a 2G/3G/4G/5G combiner.

It should be noted that the above-mentioned embodiments illustrate rather than limit the invention, and that those skilled in the art will be able to design alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim.