JP2008099310A - Antenna with one or more openings - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a new multi-holed antenna, primarily suitable for mobile communication, or generally suitable for any other applications in which an integration of a plurality of telecommunication systems or applications into a single antenna is critical. <P>SOLUTION: The antenna consists of a radiation element that includes at least one openings. This configuration provides the antenna with broadband and multi-band capabilities, accordingly features behaviors similar to using a plurality of different frequency bands. The antenna also features the size smaller than other antennas related to existing technologies that operate with the same frequency. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a novel multi-hole antenna that operates simultaneously at several frequencies with improved impedance matching. In addition, this antenna is characterized in that it is smaller in size than other antennas according to the prior art that operate at the same frequency.

  The radiating element of this novel multi-hole antenna is an antenna formed into a polygonal shape, a space-filling shape, a loading shape or a multi-level shape, and is composed of an antenna including at least one hole on the radiating antenna surface. The

  The present invention relates to a new type of multi-hole antenna that is suitable primarily for mobile communications or generally for any other application where integration of multiple telecommunications systems or applications into a single antenna is important.

The development of the telecommunications sector, and in particular the expansion of personal mobile communication systems, is an engineering effort to develop multiple systems for multiple services (multi-frequency) that require multi-frequency and small antennas. Is pouring.
US patent application Ser. No. 09/129176. Pamphlet of International Application No. WO0122528. Pamphlet of International Application No. WO0155425. Specification of International Application No. PCT / EP01 / 11914. “New Wideband Monopole Antenna”, Antenna and Propagation Society International Symposium, 1997, IEEE, vol. 1, pp. 248-251 (NP Agrawall, “New wideband monopole antennas”, Antennas and Propagation Society International Symposium, 1997, IEEE, vol. 1, pp. 248-251).

  Thus, today, using small multi-system antennas with multi-band and / or wide-band performance to provide coverage over the maximum number of services, which reduces their costs and the environment to telecommunications operators. It has become a significant concern because it enables minimizing the impact.

  Most of the reported multiband antenna solutions use one or more radiators or branches for each band or service. One example is described in Patent Document 1 entitled “Multiple band, multiple branch antenna for mobile phone”.

  Alternatives that may be of particular interest when looking for antennas with multi-band and / or small size performance include the multi-level antenna described in US Pat. A small space-filling antenna described in Patent Document 3 entitled “Space-filling miniature antennas” and a loaded antenna described in Patent Document 4 titled “Loaded Antenna” There is.

  N. Pee. Agrawal (Non-Patent Document 1) presents the result of a set of a plurality of solid planar polygonal monopole antennas, but is different from the content of the present invention.

  The gist of the present invention is the shape of a radiating element, which includes a set of a plurality of holes provided in the radiating element. According to the invention, the antenna is a monopole or dipole that includes at least one hole. The antenna may also include a plurality of different holes having different shapes and sizes in a radiating element formed by a polygonal structure, a multi-level structure or a loaded structure.

  By adding a plurality of holes to the radiating element, the antenna can be characterized by multi-frequency operation in a smaller size than other antennas according to the prior art that operate at the same frequency. For the multi-frequency operation described above, the hole in the monopole or dipole antenna is characterized by an area that is at least 20% of the area contained inside the outer periphery of the radiating element in the antenna.

  The novel monopole or dipole includes a radiating element made of a conductor material or a superconductor material having at least one hole, and the hole may be filled with a dielectric, or the conductor used for the radiating element May be partially filled with a different conductor material or superconductor material.

  In the novel antenna, the plurality of holes or portions thereof can be molded with a geometric shape selected from a set consisting of a multi-level structure, a loading structure, a space-filling structure, and a polygonal structure. is there. These geometric shapes are understood as described in the previously identified patent literature.

The main advantages of this new multi-hole antenna are the following two points.
・ This antenna features multi-frequency operation.
• The antenna can operate at a lower frequency than most of the antennas according to the prior art.

  FIG. 1 shows three different types of antennas including one hole: a circular, elliptical and rectangular antenna. Since circles and ellipses can be regarded as polygonal structures having a large number of sides, they are polygonal in all cases including circles and ellipses. Cases 1 to 3 indicate antennas whose radiating elements are circles including one hole, and the size of the holes increases in the order of cases 1 to 3, with (3b) being the largest and (1a) being the smallest. The holes included in cases 1 to 3 are also circular. Cases 4 and 5 show elliptical monopoles with elliptical holes. In case (4b), the holes are arranged asymmetrically with respect to the vertical axis of the radiating element. Case 6 shows a rectangular monopole containing one rectangular hole. In all cases shown in FIG. 1, the area of the hole is at least 20% of the area contained on the outer periphery of the radiating element.

  FIG. 2 shows three different types of multi-hole antennas. Case 7 shows a circular radiating element with two identical circular holes (7a) and a larger third hole (7b). The antennas in cases 8 and 9 are multi-hole antennas, the hole is shaped as a curve, which intersects itself at one point. Cases 10 and 11 show polygonal radiating elements having one and three holes, respectively, molded using a multilevel structure.

  FIG. 3 shows a radiating element in which case 12 has a triangular shape including one hole shaped by the space filling curve (12b). Case 13 shows a multi-hole antenna having a circular hole, which intersects the outer periphery of the radiating element at a position more than three-quarters of the outer periphery of the radiating element at a distance from the feed point. Case 14 shows a radiating element (14a) configured in a rectangular and circular shape, including two holes consisting of a circular hole (14b) and a hole (14c) formed with a multi-level structure. Case (15) shows another radiating element comprising a hole (15b) having a circular shape.

  FIG. 4 shows a loaded radiating element (16a), in which case 16 includes two rectangular holes (16b).

  FIG. 5 shows a multi-hole antenna according to two specific cases. These are comprised of a monopole with a conductor or superconductor ground plate having an opening for placing the coaxial cable (18), the outer conductor of the coaxial cable being connected to the ground plate, The inner conductor of the coaxial cable is connected to the multi-hole radiating element. This radiating element can optionally be placed on a support dielectric (20).

  FIG. 6 shows a multi-hole antenna composed of dipoles, each of the two arm portions including one hole. Line (21) indicates the input terminal point. These two figures represent different configurations of the same basic dipole, and in the lower figure the radiating element is supported by a dielectric substrate (20).

  FIG. 7 shows an aperture antenna provided with a multi-hole structure as an aperture antenna (3). This opening is provided on the conductor or superconductor structure (23).

  FIG. 8 shows an antenna array (24) including a plurality of multi-hole radiating elements (17).

  One preferred embodiment of the multi-hole antenna is a monopole configuration as shown in FIG. A handheld phone case or part of a metal structure of a car or train can act as such a grounded counterpoise. A ground plate and monopole arm portion (17) (wherein a particular embodiment of the arm portion is shown, but any of the multi-hole antenna structures described above may be employed instead. ) Is excited by, for example, the transmission line (18) as in the case of the monopole according to the prior art. The transmission line is formed by two conductors, the first conductor is connected to one point of a conductor or superconductor multi-hole structure, and the second conductor is connected to a ground plate or a ground counterpoise. In FIG. 5, a coaxial cable (18) is employed as a transmission line in a specific case, but those skilled in the art can use other transmission lines (such as a microstrip arm) to excite the monopole. It is clear that Optionally, according to the scheme just described, the multi-hole monopole can be printed, for example, on a dielectric substrate (20) and formed or attached by etching.

  FIG. 6 shows another preferred embodiment according to the present invention. A dipole antenna having two arm portions is configured to include two conductor or superconductor parts each having a multi-hole structure. For clarity, but without loss of generality, we have chosen a multi-hole antenna (17) for a particular case here, but obviously it replaces other structures, such as the one shown in FIG. It can also be used. In this particular case, two points (21) on the outer periphery of each arm part can be employed as the input part of the dipole structure. In other embodiments, other points may be employed as input terminals. Although terminal (21) is illustrated as a conductor or superconductor lead, as will be apparent to those skilled in the art, such terminals may be any other as long as their operating wavelength is kept short. It can be formed in a pattern. Those skilled in the art will realize that the dipole arm can be rotated or folded in different ways to fine-tune the input impedance or the radiation characteristics of the antenna, eg polarization.

  FIG. 6 also shows another preferred embodiment of a multi-hole dipole antenna in which a plurality of multi-hole arms are printed onto a dielectric substrate (20). This method is particularly convenient in terms of cost and mechanical robustness when the shape of the radiating element includes a large number of polygons, as occurs when using a multi-level structure. Any of known printed circuit manufacturing techniques can be applied to pattern the notched feed structure on the dielectric substrate. The dielectric substrate may be, for example, a glass fiber plate, a Teflon-based substrate (such as Cuclad®), or other standard radio frequency and microwave substrates (eg, Rogers 4003: registered). Trademark) or Kapton (registered trademark) or the like. When antennas for transmitting or receiving radio, TV, cellular telephone (GSM900, GSM1800, UMTS) or other communication service radio waves are installed on a powered vehicle such as an automobile, train or airplane, the dielectric substrate is For example, it can be part of a window glass. Of course, a balun circuit can be connected to or integrated with the input terminal of the dipole to balance the current distribution between the two arms of the dipole.

  Another preferred embodiment of the multi-hole antenna is the aperture configuration shown in FIG. In this figure, an elliptical multi-hole structure (3) forms a slot or gap embossed onto a sheet of conductor or superconductor (23). Such a sheet is, for example, a sheet on a dielectric substrate in the configuration of a printed circuit board, or one that is placed on a glass window to prevent the interior of an automobile from being heated by infrared radiation. It can be a transparent conductive transparent film, or it can be part of a metal structure of a handheld phone, car, train, ship or airplane. The feeding method can be any known in conventional slot antennas, and this is not an essential part of the present invention. In the description of FIG. 7, a coaxial cable (22) is used to feed the antenna, one of its conductors being connected to one side of the conductor sheet and the other of the sheet crossing the slot. Connected to the other side. For example, a microstrip line can be used instead of the coaxial cable.

  FIG. 8 shows another preferred embodiment. This consists of an antenna array (24) including at least one multi-hole dipole antenna (17).

Three different antennas including one hole are shown: circular, elliptical and rectangular antennas. Three different types of multi-hole antennas are shown. Case 12 shows a radiating element with a triangular shape including one hole shaped by the space-filling curve (12b), Case 13 shows a multi-hole antenna with a circular hole, and Case 14 has a rectangular and circular shape. Shown is a configured radiating element (14a), case (15) shows another radiating element comprising a hole (15b) having a circular shape. Case 16 shows a loaded radiating element (16a) comprising two rectangular holes (16b). 2 shows a multi-hole antenna according to two specific cases. A multi-hole antenna composed of dipoles, wherein each of two arm portions includes one hole. An aperture antenna provided with a multi-hole structure as an aperture antenna (3) is shown. This opening is provided on the conductor or superconductor structure (23). Shown is an antenna array (24) including a plurality of multi-hole radiating elements (17).

Claims (15)

The radiating element of the multi-hole antenna includes at least one hole,
The multi-hole antenna, wherein the hole has an area of at least 20% of an area included inside the outer periphery of the radiating element of the antenna. The radiating element is a conductor or a superconductor,
The conductor or superconductor comprises at least one hole that can be filled with a dielectric or a material of a conductor or superconductor different from the conductor used for the radiating element. The antenna according to claim 1.   3. The antenna according to claim 1, wherein the radiating element includes one hole.   The antenna according to claim 1 or 2, wherein the radiating element includes at least two holes.   The outer periphery of the radiating element, the outer periphery of at least one of the holes, or both the outer periphery of the radiating element and the outer periphery of at least one of the holes of the radiating element are triangular, square, rectangular 5. An antenna according to claim 1, 2, 3 or 4, wherein said antenna is molded in a geometric shape selected from a set of: trapezoid, pentagon, hexagon, heptagon, octagon, circle and ellipse.   The antenna according to claim 1, 2, 3, 4, or 5, wherein at least a part of the multi-hole structure is a multi-level structure or a loading structure.   At least the outer periphery of the at least one hole is a curve composed of a minimum of two segments and a maximum of nine segments, and each of the plurality of segments has a predetermined angle with respect to their neighboring segments. 7. The antenna according to claim 1, 2, 3, 4, 5, or 6, wherein the antennas are connected so as to form a straight line segment, i.e., no pair of adjacent segments define a larger straight line segment.   The antenna according to claim 1, 2, 3, 4, 5, 6 or 7, wherein at least a part of an outer periphery of the at least one hole is formed by a space filling curve.   At least one of the holes is at a distance shorter than a quarter of the outer circumference of the radiating element, or more than three-quarters of the radiating element from the feeding point of the radiating element. The antenna according to claim 1, 2, 3, 4, 5, 6, 7 or 8, which intersects the outer periphery of the antenna.   10. An antenna according to claim 1, 2, 3, 4, 5, 6, 7, 8 or 9, wherein at least one of said holes is shaped as a curve, said curve intersecting itself at at least one point.   The antenna according to any of the preceding claims, wherein the antenna is an aperture antenna whose opening shape is the same as any of the shapes of the radiating elements of the antenna described in the preceding claim. Antenna.   The antenna according to any one of the preceding claims, wherein the antenna is a monopole antenna or a dipole antenna.   The antenna is one element of an antenna array, and the array includes at least one multi-hole antenna.   The antenna according to any of the preceding claims, characterized in that the antenna is characterized by multi-band operation, broadband operation or a combination of both.   A multi-hole antenna characterized in that the radiating element is shorter than a quarter of the longest operating wavelength.

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