JP2018148292A - Distribution and synthetic circuit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a distribution and synthetic circuit capable of constituting a Butler matrix feeding circuit with a single layered substrate and capable of constituting two power supply circuits with one feed circuit.SOLUTION: The distribution and synthetic circuit includes: a dielectric lens 10 which has a plurality of 3 types holes each having different depth formed toward the center of a dielectric body from the outer periphery of a three-dimensional dielectric body which has smooth surface in the entire outer periphery at an appropriate distance from each other in a circumferential direction so as not to interfere with each other; plural input signal lines 20 each connected to the surface of the dielectric lens 10; and plural output signal lines 30 each connected to the surface of the dielectric lens 10 at the positions other than the connection positions of the input signal lines 20.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a distribution / synthesis circuit used in a power feeding circuit such as a phased array antenna.

  As a power feeding circuit used for a phased array antenna, for example, a 4-port Butler matrix power feeding circuit disclosed in Non-Patent Document 1 is known. Further, for example, a Rotman lens feeding circuit disclosed in Non-Patent Document 2 is known.

K. Uehara, T. Seki, and K. Kagoshima, “A Planar Sector Antenna for Indoor High-Speed Wireless Communication Systems”, IEICE Trans. Commun., Vol. E79-B, No. 12, pp.1773-1777, Dec. 1996. W. Rotman and R. F. Turner, “Wide-angle microwave lens for line source applications,” IEEE Trans. Antennas Propag., Vol. AP-11, No. 11, pp. 623-632, Nov 1963.

  A conventional 4-port Butler matrix power supply circuit is composed of a plurality of hybrid circuits and phase shifters, and when the number of ports exceeds 4 ports, a portion for crossing signal lines for transmitting high-frequency signals is required. Therefore, there is a problem that cannot be manufactured with a single-layer substrate. In addition, since the Rotman lens feeding circuit requires a multi-port input / output distributor consisting of two plane lenses for horizontal plane molding and vertical plane formation, there is a problem that circuit loss increases when the frequency is high. is there.

  The present invention has been made in view of these problems, and provides a distribution and synthesis circuit in which a Butler matrix power supply circuit can be configured with a single-layer substrate and two power supply circuits can be configured with a single power supply circuit. The purpose is to do.

  In the distribution and synthesis circuit according to one aspect of the present embodiment, three or more types of holes having different depths are formed from the outer peripheral portion of a three-dimensional dielectric whose outer peripheral surface has a smooth curved surface toward the center of the dielectric. A plurality of dielectric lenses that are spaced apart from each other by an appropriate distance in the circumferential direction so as not to interfere with each other, a plurality of input signal lines connected to the surface of the dielectric lens, and a dielectric lens The gist of the present invention is to include a plurality of output signal lines connected to positions other than the connection positions of the input signal lines on the surface.

  According to the present invention, it is possible to provide a distribution / synthesis circuit in which a Butler matrix power supply circuit can be configured with a single-layer substrate, and two power supply circuits can be configured with a single power supply circuit.

It is a figure which shows the perspective view of the distribution combination circuit which concerns on embodiment of this invention. It is a figure which shows the xy cross section of the distribution synthetic | combination circuit shown in FIG. It is a figure which shows the cross section of the dielectric lens of the distribution synthetic | combination circuit shown in FIG. FIGS. 4A and 4B are diagrams illustrating signal transmission characteristics of the dielectric lens illustrated in FIG. 3. FIG. 4A illustrates transmission characteristics with a hole diameter of 3 mm, and FIG. It is a figure which shows the result of having analyzed the transmission characteristic of the dielectric material lens shown in FIG. 3 by the finite element method. It is a figure which shows the xy cross section of the modification of the distribution synthetic | combination circuit which concerns on embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a perspective view of a distribution / synthesis circuit 1 according to an embodiment of the present invention. The distribution / synthesis circuit 1 includes a dielectric lens 10, an input signal line 20, and an output signal line 30.

  The number of each of the input signal line 20 and the output signal line 30 is shown by nine examples. The number of the input signal lines 20 and the number of the output signal lines 30 may be any number as long as the number is one or more.

  The input signal line 20 is a plurality of signal lines connected to the surface of the dielectric lens 10. For example, a high frequency signal is input to the dielectric lens 10. The input signal line 20 is, for example, a waveguide. Further, the input signal line 20 may be any of a microstrip line, a strip line, a suspended line, and a coplanar line.

  Further, the input signal line 20 may have a configuration in which these lines are connected to a dielectric line using a coaxial waveguide converter or the like, or a structure in which a waveguide and a dielectric line are combined. The same applies to the output signal line 30.

  The dielectric lens 10 is a lens such as a Luneberg lens, for example, and refracts and reflects a high-frequency signal input through the input signal line 20 inside. FIG. 1 shows the dielectric lens 10 as a sphere, for example.

  The dielectric lens 10 is arranged in the circumferential direction so that, for example, three or more holes having different depths do not interfere with each other toward the center of the dielectric from the outer peripheral portion of a Teflon (registered trademark) sphere having a radius of 30 mm. A plurality of spaces are provided in the entire outer peripheral portion with appropriate intervals. Therefore, the high-frequency signal input from the input signal line 20 to the dielectric lens 10 passes through the two parts of the Teflon resin layer having a relative permittivity of 2.1 and the air layer having a relative permittivity of 1.0 and reaches the output signal line 30. It will be.

  Since three or more kinds of holes having different depths are formed in the sphere so that they do not interfere with each other, the air layer has a higher density near the outer periphery of the sphere. The closer it is, the lower the density of the air layer. Therefore, the relative dielectric constant obtained by adding the Teflon resin and the air layer is the largest at the center of the dielectric lens 10 and decreases toward the surface.

  In FIG. 1, the output signal line 30 is disposed at a position facing the input signal line 20 with the dielectric lens 10 interposed therebetween. Further, the arrangement of the input signal line 20 and the output signal line 30 is not limited to this example. The output signal line 30 may be connected to a position other than the connection position of the input signal line 20 on the surface of the dielectric lens 10.

  In the distribution and synthesis circuit 1 configured as described above, for example, a Butler matrix power supply circuit can be configured with a single-layer substrate. That is, since the dielectric lens 10 is responsible for intersecting signal lines for transmitting high-frequency signals, the input signal line 20 and the output signal line 30 are arranged on a single substrate even if the signal lines need to be intersected. Can do.

  Further, according to the distribution and synthesis circuit 1, it is possible to easily configure two power supply circuits for horizontal plane molding and vertical plane molding. For example, if the input signal line 20 and the output signal line 30 are arranged in the z-axis direction of FIG. 1, the high frequency signal is distributed and synthesized in two systems of the horizontal plane and the vertical plane by the action of one dielectric lens 10. Is possible.

  FIG. 2 is a cross-sectional view of the distribution and synthesis circuit 1 cut along the xy cross section of FIG. Three input signal lines 20 and output signal lines 30 on the x-axis can be confirmed. With reference to FIG. 2, the distribution / synthesis circuit 1 of the present embodiment will be described in more detail.

  In FIG. 2, the hierarchical structure indicated by a dashed-dotted circle from the center of the dielectric lens 10 toward the surface indicates that the relative dielectric constants are hierarchically different. For example, a high-frequency signal input from the input signal line 20 to the dielectric lens 10 is refracted and reflected at the interface between the Teflon resin layer and the air layer and output from the output signal line 30. The reflection includes a reflection on the inner surface of the dielectric lens 10. Therefore, the high-frequency signal input from the input signal line 20 to the dielectric lens 10 is dispersed and output from the output signal line 30.

(Dielectric lens)
FIG. 3 shows a cross-sectional view of the dielectric lens 10. FIG. 3 is a diagram showing the dielectric lens 10 taken out from the distribution / synthesis circuit 1 of FIG.

  Dielectric lens 10 has a hole with a depth of 5/6 radius for every 90 degree central angle, a hole with a depth of 4/6 radius for every 45 degree central angle, and a center angle of 22.5 degrees. A hole with a depth of 3/6 of the radius, a hole with a depth of 2/6 for each central angle of 11.25 degrees, and a hole with a depth of 1/6 of a radius for each central angle of 5.625 degrees Is provided. These holes form a change in the dielectric constant that changes stepwise. In this example, a layer having a dielectric constant of 6 levels is formed.

  The five types of holes shown in FIG. 3 are provided on the circumference at intervals of about 2.94 mm. For example, when the depth of the hole is four types, the interval between the holes is about 5.88 mm. As described above, the interval between the holes is appropriately determined according to the number of types of the holes (depths).

FIG. 4 shows the relationship between the hole diameter and the frequency characteristics. FIG. 4A shows a hole diameter = 3 mm, and FIG. 4B shows a hole diameter = 2 mm. In FIG. 4, the horizontal axis represents frequency, and the vertical axis represents S parameter S ₂₁ [dB]. The radius of the dielectric lens 10 was 30 mm, and the material used was Teflon resin.

  As shown in FIG. 4, the transmittance of the high frequency signal gradually decreases as the frequency increases, and when the frequency exceeds 33 GHz, a frequency at which the transmittance value rapidly deteriorates appears. The wavelength λ of 33 GHz at which the transmittance value deteriorates rapidly is about 9.1 mm. Therefore, from the characteristics of FIG. 4A (hole diameter = 3 mm), it is considered that the hole diameter needs to be one third of the wavelength λ of the frequency signal to be used.

  This can also be confirmed by the characteristics shown in FIG. 4B (hole diameter = 2 mm). The pore diameter = 2 mm is 50 GHz in terms of wavelength λ. Therefore, as shown in FIG. 4 (b), the transmission characteristic gently attenuates to 40 GHz.

  FIG. 5 shows the result of analyzing the electromagnetic wave transmission characteristics of the dielectric lens 10 shown in FIG. 3 by the finite element method. The vertical direction in FIG. 5 indicates the electric field distribution in the z-axis direction, and the horizontal direction indicates the electric field distribution in the y-axis direction.

  The electric field strength is 5.0 to 3.3 kV / m for the hatched area with fine left diagonal lines, 3.3 to 1.7 kV / m for the cross hatch area, 1.7 to 1.0 kV / m for the lower right hatch area, and rough left oblique line The hatched portion is 1.0 to 0.7 kV / m, and the white portion is 0.7 to 0 kV / m.

  From FIG. 5A, it can be seen that the high frequency signal incident from the negative direction on the y-axis of the dielectric lens 10 is distributed and outputted to three curved surfaces on the outer peripheral surface on the opposite side of the dielectric lens 10. I understand. Also, from FIG. 5B, the high frequency signal incident near the central angle of 45 degrees of the dielectric lens 10 is bent inside the dielectric lens 10 and is approximately −y from above the curved surface on the opposite side. You can see how it is output in the direction.

  Thus, the lens effect with respect to the high frequency signal of the dielectric lens 10 of this embodiment was able to be confirmed. Such distribution / synthesis characteristics for high-frequency signals can be confirmed by making three or more holes having different depths.

(Modification)
FIG. 6 shows a modified distribution / synthesis circuit 2. FIG. 6 is a cross-sectional view of the distribution and synthesis circuit 2 taken along the xy cross section in the same manner as the relationship between FIGS. 1 and 2. The dielectric lens 11 of the distribution / synthesis circuit 2 has, for example, a three-dimensional shape similar to a rugby ball.

  The xy cross section of the dielectric lens 11 is elliptical. Thus, the shape of the dielectric lens is not limited to a sphere.

  The dielectric lens 11 may not be a spherical or rugby ball-shaped solid. For example, the disk may have a circular cross section. For example, in the example of FIG. 1, the dielectric lens 10 is an example of a sphere, but in the example of the input signal line 20 and the output signal line 30 illustrated in FIG. 1, the shape of the dielectric lens 10 may be a disk. That is, the dielectric lens 10 in the case of dispersing a signal only in one direction may be a disk having the thickness of the input signal line 20 and the output signal line 30. Moreover, a cylindrical shape may be sufficient. In this case, the relative dielectric constant does not change in the z-axis direction.

(Production method)
The dielectric lenses 10 and 11 are formed using a dielectric material such as Teflon resin or liquid crystal polymer resin, for example. The dielectric lenses 10 and 11 can be easily formed by molding with a three-dimensional image apparatus (3D printer). The input signal line 20 and the output signal line 30 can also be formed at the same time.

  In the manufacturing method of the distribution / synthesis circuit according to the present embodiment, the distribution / synthesis circuits 1 and 2 have three or more types of holes having different depths from the outer peripheral portion of the solid dielectric whose outer peripheral surface has a smooth curved surface. A plurality of dielectric lenses 10 and 11 that are spaced apart from each other in the circumferential direction so as not to interfere with each other toward the center of the body, and a plurality of dielectric lenses 10 and 11 connected to the surfaces of the dielectric lenses 10 and 11 The input signal line 20 and a plurality of output signal lines 30 connected to positions other than the connection position of the input signal line 20 on the surface of the dielectric lenses 10 and 11 are manufactured. The input signal line 20 and the output signal line 30 are integrally formed using a three-dimensional image apparatus.

  As described above, according to the distribution and synthesis circuit of the present embodiment, a simple structure in which the input signal line 20 and the output signal line 30 corresponding to the antenna elements of the array antenna are arranged on the surface of the dielectric lens 10, for example, A feeding circuit for a phased array antenna can be realized. Further, since the power feeding circuit for horizontal and vertical molding can be realized integrally, the size can be reduced, and the loss due to the circuit can also be reduced.

  In addition, although the content of this invention was demonstrated along embodiment, it is obvious to those skilled in the art that this invention is not limited to these description and various deformation | transformation and improvement are possible. For example, although the input signal line 20 and the output signal line 30 illustrated in FIG. 1 are provided in the y-axis direction, they may be arranged on the outer peripheral surface in the z-axis direction. Thus, the present invention is not limited to the above-described embodiment, and can be modified within the scope of the gist thereof.

1, 2: Distribution / synthesis circuit 10, 11: Dielectric lens 20: Input signal line 30: Output signal line

Claims (3)

Three or more types of holes with different depths from the outer peripheral portion of the three-dimensional dielectric having a smooth curved outer peripheral surface are appropriately spaced in the circumferential direction so as not to interfere with each other toward the center of the dielectric. A plurality of dielectric lenses spaced over the entire outer periphery;
A plurality of input signal lines connected to the surface of the dielectric lens;
And a plurality of output signal lines connected to positions other than the connection positions of the input signal lines on the surface of the dielectric lens. In the case where the shape of the dielectric lens is a sphere,
2. The distribution and synthesis circuit according to claim 1, wherein the depth of the hole is n / 6th of the radius of the sphere, wherein n is an integer of 5 or less.   3. The distribution / synthesis circuit according to claim 1, wherein the diameter of the hole is one-third or less of a wavelength of a frequency to be used.

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