阅读说明：本技术 一种超宽带恒波束定向天线 (Ultra-wideband constant-beam directional antenna ) 是由 张建丰 王庆祥 于 2020-07-01 设计创作，主要内容包括：本发明公开了一种超宽带恒波束定向天线,包括辐射体,辐射体采用具有非频变超宽带特性的印刷对数周期天线,包括镜像对称的两副印刷对数周期天线,两副印刷对数周期天线在垂直天线平面的方向上顶端靠拢,组成倒V形阵,在倒V形阵的顶角处,两副印刷对数周期天线之间留有预设的顶角间距。通过采用具有非频变超宽带特性的印刷对数周期天线,将两副印刷对数周期天线镜像对称,构成倒V形阵,且控制两副印刷对数周期天线在倒V形阵的顶角处留有预设的顶角间距,利用这样的结构设计,使得该定向天线的波束宽度恒定,波动很小,信号传输稳定,同时,本申请辐射体采用印刷对数周期天线的形式,具有小型化、轻质量、易加工、低成本和一致性好等优点。(The invention discloses an ultra-wideband constant-beam directional antenna, which comprises a radiator, wherein the radiator adopts a printing log periodic antenna with a non-frequency-variable ultra-wideband characteristic, the radiator comprises two printing log periodic antennas in mirror symmetry, the top ends of the two printing log periodic antennas are close in the direction vertical to the plane of the antenna to form an inverted V-shaped array, and a preset vertex angle interval is reserved between the two printing log periodic antennas at the vertex angle of the inverted V-shaped array. Through adopting the printing log periodic antenna who has the non-frequency change ultra wide band characteristic, with two pairs of printing log periodic antenna mirror symmetry, constitute the shape of falling V battle array, and control two pairs of printing log periodic antennas and leave predetermined apex angle interval in the apex angle department of the shape of falling V battle array, utilize such structural design for this directional antenna's beam width is invariable, and the fluctuation is very little, and signal transmission is stable, and simultaneously, this application irradiator adopts the form of printing log periodic antenna, has advantages such as miniaturization, light weight, workable, low cost and uniformity are good.)

1. An ultra wide band constant beam directional antenna, includes the radiator, its characterized in that: the radiator adopts a printing log periodic antenna with the non-frequency-variable ultra-wideband characteristic, the printing log periodic antenna comprises two printing log periodic antennas which are in mirror symmetry, the top ends of the two printing log periodic antennas are close in the direction perpendicular to the plane of the antenna to form an inverted V-shaped array, and a preset vertex angle distance is reserved between the two printing log periodic antennas at the vertex angle of the inverted V-shaped array.

2. The ultra-wideband constant-beam directional antenna of claim 1, wherein: and the beam widths of the E surface and the H surface of the inverted V-shaped array are consistent.

3. The ultra-wideband constant-beam directional antenna of claim 1, wherein: the spacing factors of the printed log periodic antennas form an arithmetic progression.

4. The ultra-wideband constant-beam directional antenna of claim 3, wherein: the printed log periodic antenna has a scale factor τ of 0.885, an initial value of spacing factor σ of 0.0915, a tolerance of 0.0015, and an aggregate line width w₀Is 3.2-4 mm.

5. The ultra-wideband constant-beam directional antenna of claim 1, wherein: the directional antenna also comprises a metal round core and a semi-rigid coaxial cable; the semi-rigid coaxial cable feeds the directional antenna through the metal round core; the metal round core penetrates through a hole at the top end of the inverted V-shaped array and is electrically connected with the copper-clad layer on the outer side of the inverted V-shaped array; the inner conductor of the semi-rigid coaxial cable is electrically connected with the metal round core, and the outer conductor of the semi-rigid coaxial cable is electrically connected with the copper-clad layer on the inner side of the inverted V-shaped array.

6. The ultra-wideband constant-beam directional antenna of claim 1, wherein: the directional antenna also comprises a metal grounding plate, and the bottom ends of the two pairs of the printed log periodic antennas are arranged on the upper surface of the metal grounding plate.

7. The ultra-wideband constant-beam directional antenna of claim 6, wherein: the directional antenna also comprises two auxiliary supporting plates arranged on the metal grounding plate; the two pairs of supporting plates are arranged in a mirror symmetry mode, an inverted V-shaped groove is formed in the surface of one side of each supporting plate, the width of a groove line of the inverted V-shaped groove is equal to the thickness of the printing logarithmic period antenna, the vertex angle degree of the inverted V-shaped groove is equal to that of the inverted V-shaped array, the supporting plates are arranged on the two sides of the inverted V-shaped array respectively, and the inverted V-shaped array is supported and positioned through the inverted V-shaped groove.

8. The ultra-wideband constant-beam directional antenna of claim 7, wherein: the backup pad is hollow out construction, includes a plurality of trompils.

9. The ultra-wideband constant-beam directional antenna of claim 5, wherein: the directional antenna further comprises a pair of identical fixing plates and a pair of identical positioning cylinders; the fixed plate with the location cylinder sets up the apex angle end of falling V-arrangement battle array, the fixed plate with the location cylinder all opens fixedly the draw-in groove of printing log periodic antenna, through the draw-in groove is right the apex angle end of falling V-arrangement battle array carries out the fixed of contained angle and interval.

10. The ultra-wideband constant-beam directional antenna of claim 6, wherein: and the upper surface of the metal grounding plate is provided with a wave-absorbing material layer.

Technical Field

The invention relates to the technical field of antennas, in particular to an ultra-wideband constant-beam directional antenna.

Background

The antenna is a mutual converter for the signal inside the radio detection equipment to propagate between the transmission line and the free space, and the quality of the antenna performance basically determines the quality of the technical index of the whole detection system. Because various detection devices work in various different frequency bands, an electromagnetic wave space with an extremely wide frequency band is formed in a working area, and antennas of detection devices such as radars, communication devices and the like are required to have very wide frequency bands for simultaneously detecting a plurality of targets; in pursuit of longer detection distance and higher receiving sensitivity, larger antenna gain is required; in pursuit of higher acquisition rate and detection accuracy, antenna beam equalization and constant beam width are required. In this case, an antenna having both a wide frequency band and a high gain is an excellent choice for the radio detecting device.

Current constant beam antennas include Vivaldi antennas (Vivaldi antennas are slot microstrip antennas that control electromagnetic waves to radiate electromagnetic energy from one end of a slot to an open end by using an exponential-shaped slot structure), helical antennas, horn antennas, and other directional antenna forms. Although the working bandwidth of the planar helical antenna is very wide (10 octaves), the beam width is relatively constant, but the gain is relatively low (about 5dBi at most), the waveform is easy to change, and the beam pointing stability is poor, so that the improvement of the receiving sensitivity and the pointing accuracy is not facilitated; the constant-beam horn antenna generally adopts a corrugated horn antenna form or a horn antenna form of which the horn outer arm is in a certain special function curve such as an ellipse, an index and the like, and although the gain of the constant-beam horn antenna is higher (about 10 dBi) in a working frequency band, the working bandwidth of the constant-beam horn antenna is limited and is not more than 3 octaves; the Vivaldi antenna has a wide working bandwidth (10 octaves) and a constant beam width, and has a higher gain (which can reach 7-8 dBi) compared with a planar helical antenna, but the E-plane directional diagram and the H-plane directional diagram in the whole working frequency band have a larger difference, the beam equalization degree is not high, and the interception rate and the detection precision of a detection device are affected.

Therefore, it is desirable to provide an ultra-wideband constant-beam directional antenna with better effect.

Disclosure of Invention

In view of the problem of poor effect of various types of constant wave beams in the prior art, the invention provides the ultra-wideband constant wave beam directional antenna so as to overcome the problem.

In order to achieve the purpose, the invention adopts the following technical scheme:

the utility model provides an ultra wide band constant beam directional antenna, includes the irradiator, the printing log periodic antenna that the irradiator adopted and to have the non-frequency change ultra wide band characteristic, including mirror symmetry's two pairs of printing log periodic antenna, two pairs the printing log periodic antenna top in the direction of perpendicular antenna plane is drawn close, constitutes the shape of falling V array the apex angle department of shape of falling V array, two pairs leave predetermined apex angle interval between the printing log periodic antenna.

Optionally, the E-plane and H-plane beam widths of the inverted V-shaped array are the same.

Optionally, the spacing factors of the printed log periodic antennas form an arithmetic series.

Optionally, the printed log periodic antenna has a scale factor τ of 0.885, an initial value of spacing factor σ of 0.0915, a tolerance of 0.0015, and an aggregate line width w₀Is 3.2-4 mm.

Optionally, the directional antenna further comprises a metal round core and a semi-rigid coaxial cable; the semi-rigid coaxial cable feeds the directional antenna through the metal round core; the metal round core penetrates through a hole at the top end of the inverted V-shaped array and is electrically connected with the copper-clad layer on the outer side of the inverted V-shaped array; the inner conductor of the semi-rigid coaxial cable is electrically connected with the metal round core, and the outer conductor of the semi-rigid coaxial cable is electrically connected with the copper-clad layer on the inner side of the inverted V-shaped array.

Optionally, the directional antenna further comprises a metal ground plate, and the bottom ends of the two pairs of printed log periodic antennas are mounted on the upper surface of the metal ground plate.

Optionally, the directional antenna further comprises two sub-supporting plates disposed on the metal ground plate; the two pairs of supporting plates are arranged in a mirror symmetry mode, an inverted V-shaped groove is formed in the surface of one side of each supporting plate, the width of a groove line of the inverted V-shaped groove is equal to the thickness of the printing logarithmic period antenna, the vertex angle degree of the inverted V-shaped groove is equal to that of the inverted V-shaped array, the supporting plates are arranged on the two sides of the inverted V-shaped array respectively, and the inverted V-shaped array is supported and positioned through the inverted V-shaped groove.

Optionally, the supporting plate is a hollow structure and comprises a plurality of openings.

Optionally, the directional antenna further comprises a pair of identical fixing plates and a pair of identical positioning cylinders; the fixed plate with the location cylinder sets up the apex angle end of falling V-arrangement battle array, the fixed plate with the location cylinder all opens fixedly the draw-in groove of printing log periodic antenna, through the draw-in groove is right the apex angle end of falling V-arrangement battle array carries out the fixed of contained angle and interval.

Optionally, the upper surface of the metal grounding plate is provided with a wave-absorbing material layer.

In conclusion, the beneficial effects of the invention are as follows:

according to the invention, the printed logarithmic period antennas with the non-frequency-variable ultra-wideband characteristic are adopted, two pairs of printed logarithmic period antennas are in mirror symmetry to form the inverted V-shaped array, and the preset vertex angle interval is reserved at the vertex angle of the inverted V-shaped array by controlling the two pairs of printed logarithmic period antennas.

Drawings

Fig. 1 is a schematic structural diagram of a directional antenna according to an embodiment of the present invention;

fig. 2 is a schematic diagram of an inverted-V array formed by two pairs of printed log periodic antennas in a directional antenna according to an embodiment of the present invention;

fig. 3 is a schematic structural diagram of a single printed log periodic antenna in a directional antenna according to an embodiment of the present invention;

FIG. 4 is a measured standing wave voltage ratio for a directional antenna according to an embodiment of the present invention;

FIG. 5 is a measured gain curve for a directional antenna according to an embodiment of the present invention;

fig. 6 to 10 are directional diagrams of a directional antenna according to an embodiment of the present invention, in which azimuth planes (H-plane) and elevation planes (E-plane) are actually measured at each frequency point, and beam widths thereof;

in the figure: 1. an ultra-wideband constant-beam directional antenna; 2. a metal ground plate; 3. an inverted V-shaped array; 3a, printing a log periodic antenna; 3b, printing a log periodic antenna; 4. a semi-rigid coaxial cable; 5. a support plate; 6. a support plate; 7. a connecting rod; 8. a wave-absorbing material layer; 9. flanging; 10. a fixing plate; 11. and (5) positioning the cylinder.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplicity of description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present application. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present application, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present application can be understood in a specific case by those of ordinary skill in the art.

The log periodic antenna is a non-frequency-varying antenna, and the non-frequency-varying antenna means that electrical characteristics such as impedance, a directional diagram, gain, a standing-wave ratio and the like of the antenna periodically change along with the logarithm of frequency and are kept basically unchanged in a wide frequency band.

The Ultra Wide Band (UWB) technology is a novel wireless communication technology. It makes the signal have a bandwidth of the order of GHz by directly modulating an impulse with very steep rise and fall times.

The technical conception of the invention is as follows: through adopting the printing log periodic antenna who has the non-frequency change ultra wide band characteristic, with two pairs of printing log periodic antenna mirror symmetry, constitute the shape of falling V battle array, and control two pairs of printing log periodic antennas and leave predetermined apex angle interval in the apex angle department of the shape of falling V battle array, utilize such structural design for this directional antenna's beam width is invariable, and the fluctuation is very little, and signal transmission is stable, and simultaneously, this application irradiator adopts the form of printing log periodic antenna, has advantages such as miniaturization, light weight, workable, low cost and uniformity are good.

Fig. 1 is a schematic structural diagram of a directional antenna according to an embodiment of the present invention, and fig. 2 is a schematic structural diagram of an inverted V-shaped array radiator of the directional antenna in fig. 1. As shown in fig. 1 and 2, the ultra-wideband constant-beam directional antenna 1 of the present application includes a radiator. The radiator adopts a printed log periodic antenna with the non-frequency-varying ultra-wideband characteristic, and comprises two pairs of printed log periodic antennas in mirror symmetry, namely the printed log periodic antennas 3a and 3b in fig. 1 and 2. The two pairs of printed log periodic antennas are close to each other at the top end in the direction vertical to the plane of the antennas to form an inverted V-shaped array 3. Referring to the schematic diagram of the inverted V-shaped array shown in fig. 2 of the present application, the included angle between the vertex angles of the two pairs of printed log periodic antennas 3a and 3b is γ, and a preset vertex angle distance d is left between the two pairs of printed log periodic antennas at the vertex angle of the inverted V-shaped array 3.

In the preferred embodiment of the present application, the dielectric constant of the dielectric substrate on which the log periodic antennas 3a and 3b are printed is selected_rRogers 5880 sheet with a tangent loss tan of 0.0009 at 2.2, dielectric substrate thickness of 2 mm.

In the preferred embodiment of the present application, the directional antenna further comprises a metal round core (not shown) and a semi-rigid coaxial cable 4. The semi-rigid coaxial cable 4 feeds the directional antenna through the metal round core; the metal round core penetrates through a hole at the top end of the inverted V-shaped array 3 and is electrically connected with the copper-clad layer on the outer side of the inverted V-shaped array 3; the inner conductor of the semi-rigid coaxial cable 4 is electrically connected with the metal round core, and the outer conductor of the semi-rigid coaxial cable 4 is electrically connected with the copper-coated layer on the inner side of the inverted V-shaped array 3.

In a preferred embodiment of the present application, the directional antenna further comprises a metallic ground plane 2, see fig. 1. The bottom ends of the two pairs of printed log periodic antennas 3a and 3b are mounted on the upper surface of the metallic ground plate 2.

More preferably, in one embodiment of the present application, the upper surface of the metal ground plate is further provided with a wave-absorbing material layer 8.

As shown in fig. 1, the bottom ends of two pairs of printed log periodic antennas 3a and 3b, which are distant from each other, are mounted on the upper surface of a metal ground plate 2. Specifically, the upper surface of the metal ground plate has a raised flange 9, and the printed log periodic antennas 3a and 3b are fixedly connected to the flange 9 by a fastener, such as a screw.

According to the preferred embodiment of the present invention, the semi-rigid coaxial cable 4 feeds the directional antenna through the metal round core; the metal round core penetrates through a hole at the top end of the inverted V-shaped array 3 and is electrically connected with the copper-clad layer on the outer side of the inverted V-shaped array 3; at one end of the semi-rigid coaxial cable 4, the inner conductor is electrically connected with the metal round core (i.e. connected with the copper-coated layer outside the inverted-V-shaped array 3), the outer conductor is electrically connected with the copper-coated layer inside the inverted-V-shaped array 3, the other end of the semi-rigid coaxial cable 4 is connected with the radio frequency socket, and the radio frequency socket is fixedly connected with the metal grounding plate 2 by using a fastener, such as a screw.

This application embodiment replaces the combiner in the current antenna with half just coaxial cable 4, directly to the 3 feed signals of shape of falling V, has about 0.5 dB's insertion loss like this, compares and uses the combiner, can reduce about 1 dB's insertion loss to improve this application directional antenna's gain, about 1 dBi.

In the preferred embodiment of the application, according to the electrical performance index of the directional antenna, the gain of the single pair of printed log periodic antennas is designed to be more than or equal to 7.5dBi, the E-plane beam width is 55-65 degrees, the H-plane beam width is 110-130 degrees, and the output impedance is 80-120 omega. The scale factor tau and the spacing factor sigma of the log-periodic antenna determine the gain and the beam width of the antenna, and the aggregate line width w of the log-periodic antenna₀Determines the output impedance of the antenna. Finally, the embodiment of the application is optimized to determine the tau of the printed log periodic antenna to be 0.885, sigma to be 0.0915, and w₀About 3.2 to 4mm, preferably 3.5 mm.

The single-pair printed log periodic antenna designed by the parameters has the relation that the beam width of an H surface is 2 times wider than that of an E surface. This application sets up two pairs of printing log periodic antenna mirror symmetry, constitutes V-arrangement battle array 3 to the beam width of compression H face through adjusting V-arrangement battle array 3's apex angle contained angle gamma and apex angle interval d, makes V-arrangement battle array 3's E face and H face beam width unanimous.

In a preferred embodiment of the present application, the spacing factors of the printed log periodic antennas form an arithmetic series. Because the operating frequency of the inverted V-shaped array 3 has 10 times of frequency, the equality of the directional diagram in the whole frequency band is difficult to ensure, therefore, the applicant forms an equal difference array by printing the interval factors of the log periodic antenna, and the equality of the directional diagram of the directional antenna in the whole frequency band can be improved.

Continuing with the above optimized parameters for the printed log periodic antenna, in a preferred embodiment of the present application, the printed log periodic antenna has a scale factor τ of 0.885, an initial value for the spacing factor σ of 0.0915, a tolerance of 0.0015, and a collective line width w₀Is 3.2-4 mm. Fig. 3 shows a schematic structural diagram of a printed log periodic antenna in the directional antenna of the present application, and specific geometric parameters of the printed log periodic antenna are shown in table 1 below.

TABLE 1 number of vibrators, length and width of vibrator, and spacing between vibrators for log periodic antenna

Because the number of the reflection vibrators near the excitation area is not enough, the standing wave and the back lobe of the inverted V-shaped array 3 in the frequency band of 0.9-1 GHz are too large, and therefore the metal grounding plate 2 is installed at the lower end of the inverted V-shaped array 3, impedance matching of the low frequency band of 0.9-1 GHz is facilitated, the back lobe is reduced, and gain is improved. In one embodiment of the present application, the metallic ground plate 2 is a metal plate of phi 265 mm.

With respect to the arrangement of the metal grounding plate 2, although the impedance characteristic and the radiation performance of the low frequency band of the inverted V-shaped array 3 can be improved by arranging the metal grounding plate 2, the high frequency band (7-9 GHz) directional diagram can generate waveform fluctuation, and is not smooth, and the beam width is not constant, thereby affecting the pointing accuracy. Therefore, in the preferred embodiment of the present application, the wave-absorbing material layer 8 (wave-absorbing rate S11 < -20dB @ 7-9 GHz) is further disposed on the upper surface of the metal ground plate 2, and the wave-absorbing material layer 8 is used to absorb the incident wave of the high-frequency band backward radiated to the metal ground plate 2, and suppress the reflected wave thereof, so as to improve the irregular fluctuation of the waveform. The wave-absorbing material layer 8 can be formed on the surface of the metal grounding plate 2 through a coating process, and the sheet-shaped wave-absorbing material layer 8 can also be adhered to the surface of the metal grounding plate 2.

As shown in fig. 1, in one embodiment of the present application, the directional antenna further includes two sub-supporting plates, i.e., a supporting plate 5 and a supporting plate 6, disposed on the metal ground plate 2; two accessory shoe plate mirror symmetry set up, and open on one side surface of backup pad has the recess of falling V-arrangement, and the groove line width of the recess of falling V-arrangement is the same with the thickness of printing log periodic antenna, and the apex angle number of degrees of the recess of falling V-arrangement is the same with the apex angle number of degrees of the battle array of falling V-arrangement 3 to, set up backup pad 5 and backup pad 6 respectively in the both sides of the battle array of falling V-arrangement 3, support the location through the recess of falling V-arrangement to the battle array of falling V-arrangement 3, see that fig. Specifically, the bottom ends of the support plate 5 and the support plate 6 are fixed on the metal ground plate 2, the metal ground plate 2 is provided with a flange 9 corresponding to the support plate, and the support plate is fixed at the flange 9 by a fastener such as a screw.

In one embodiment of the present application, a plurality of connecting rods 7 for fixedly connecting the two supporting plates are further disposed between the two supporting plates.

As shown in fig. 1, in an embodiment of the present application, the supporting plate is a hollow structure and includes a plurality of openings, so that the weight of the supporting plate is reduced, and the light weight of the directional antenna is realized.

In one embodiment of the present application, as shown in fig. 1, the directional antenna further comprises a pair of identical fixing plates 10 and a pair of identical positioning cylinders 11; the fixed plate 10 and the positioning column 11 are arranged at the vertex angle end of the inverted V-shaped array 3, the fixed plate 10 and the positioning column 11 are both provided with clamping grooves for fixing the printing log periodic antenna, and the vertex angle end of the inverted V-shaped array 3 is fixed at an included angle and an interval through the clamping grooves.

Fig. 4 to fig. 10 show measured technical indexes of the directional antenna according to the embodiment of the present invention, such as standing-wave ratio, gain, directional diagram, and beam width thereof, and it can be seen from the figures that the directional antenna according to the present invention realizes the following technical indexes:

1) the working frequency range is as follows: 0.9-9 GHz;

2) voltage standing wave ratio: less than 2;

3) gain: not less than 9 dBi;

4) e-plane and H-plane beam widths: 55 to 70 degrees.

To sum up, this application ultra wide band constant beam directional antenna utilizes the printing log periodic antenna that two pairs of mirrors symmetry set up, constitutes the shape of falling V array irradiator, in 10 by the operating frequency channel of frequency, the gain height (more than or equal to 9dBi), beam width is invariable, fluctuates for a short time (55 ~ 70 °), and the syntonization such as directional diagram is good. The characteristics of the directional antenna can ensure that the radio detection equipment can realize the remote detection of signals only by using a small number of antennas, can cover communication signals such as satellite navigation, remote control and image transmission data chains, and carrier-borne, land-based and airborne search/early warning radar signals, and has the advantages of simple structure, small volume and low cost.

While the foregoing is directed to embodiments of the present invention, other modifications and variations of the present invention may be devised by those skilled in the art in light of the above teachings. It should be understood by those skilled in the art that the foregoing detailed description is for the purpose of better explaining the present invention, and the scope of the present invention should be determined by the scope of the appended claims.