JP5522449B2 - Composite dipole antenna device - Google Patents

Description

  The present invention relates to a multi-wire or composite dipole antenna device used for transmission / reception of a broadband wireless signal.

  Conventionally, a dipole antenna is configured to include an antenna element, that is, an element, and operates by applying a voltage fed through a power feeding unit to the element to transmit / receive a radio signal to / from a wireless communication device. Can do.

  Since the wireless communication device is usually configured to transmit and receive wireless signals specifically for a predetermined frequency band, the dipole antenna can effectively transmit and receive wireless signals in the frequency band corresponding to the wireless communication device. Designed and configured to.

  In addition, the dipole antenna can be designed and configured to be compatible with transmission and reception of radio signals having a wide frequency range. For example, a plurality of elements are arranged in a conical shape, or as described in Patent Document 1, Is formed as a biconical antenna. Such a biconical antenna can be used for a malfunction test and electric field strength measurement of a radio communication apparatus that transmits and receives a wideband radio signal, for example, a UWB (Ultra Wide Band) signal, a radar or an FM (Frequency Modulation) signal.

JP 2004-215161 A

  However, when a conventional dipole antenna is designed to support a radio signal in a wide frequency band, it is difficult to realize effective resonance for a radio signal in a low frequency band, for example, a frequency of 20 MHz.

  When electric field strength is measured using this dipole antenna, for example, when measuring electric field strength for a frequency of 20 MHz using 10 KW of electric power, only electric field strength of about 25 V / m can be obtained. For example, the standard for EMI (Electro-Magnetic Interference) testing of electronic equipment mounted on automobiles requires an electric field strength of 100 V / m, so when using a conventional dipole antenna, the received signal In order to amplify, it is necessary to provide an amplifier with a large gain.

  In addition, when a dipole antenna handles a radio signal in a low frequency band, it is necessary to lengthen the element. However, since electric field strength measurement may be performed indoors, for example, in a shielded room, a large antenna with a long element is required. The device is disadvantageous.

  In view of such problems, the present invention is suitable for transmission / reception of a wideband wireless signal, and can resonate efficiently even with a low frequency band wireless signal to obtain a high electric field strength. An object of the present invention is to provide a dipole antenna device.

  In order to solve the above-described problems, the present invention includes a plurality of dipole antennas each having a pair of elements, and a composite dipole antenna device that operates by supplying power to the elements via a power feeding unit. In each of the dipole antennas, the element is formed of a linear or rod-like conductor having substantially the same length and shape as each other, and is arranged substantially symmetrically with respect to the feeding portion. The at least two of the plurality of dipole antennas are of different lengths and are adapted to fit different frequency bands, in at least one of the plurality of dipole antennas, the conductor is Each of the plurality of divided conductors has a plurality of divided conductors branched from each other and having respective end points. Route to the end point through the split conductor, to match the different frequency bands, characterized in that it is formed in different lengths.

  According to the present invention, a multi-wire or composite dipole antenna device includes a plurality of dipole antennas that are adapted to different frequency bands, and at least one dipole antenna includes a plurality of divided conductors and a plurality of end points. A plurality of divided conductors are formed with different lengths so that a plurality of paths passing through each divided conductor are adapted to different frequency bands from each other. It can adapt to a wideband radio signal including a band, for example, a frequency band of 20 MHz.

  In the composite dipole antenna device of the present invention, the element in at least one dipole antenna has a main body formed by bending a conductor within a predetermined two-dimensional plane, and further includes at least two such elements. When applied to two or more dipole antennas, the lengths from the beginning to the end of the element can be made equal regardless of the frequency band in which the dipole antenna is suitable. Thereby, this apparatus can make the size small and can be comprised by the size match | combined with limited places, such as the shield room arrange | positioned.

It is a projection view which shows one Example of the composite dipole antenna apparatus which concerns on this invention. It is sectional drawing of the transversal direction of the composite dipole antenna apparatus shown in FIG. It is a figure which shows one Example of the element in the composite dipole antenna apparatus shown in FIG. It is a figure which shows one Example of the element in the composite dipole antenna apparatus shown in FIG. It is a figure which shows one Example of the element in the composite dipole antenna apparatus shown in FIG. It is a figure which shows one Example of the element in the composite dipole antenna apparatus shown in FIG. It is a figure which shows one Example of the element in the composite dipole antenna apparatus shown in FIG. It is a graph which shows the voltage standing wave ratio obtained with the composite dipole antenna apparatus shown in FIG.

  Next, an embodiment of a multi-wire or composite dipole antenna device according to the present invention will be described in detail with reference to the accompanying drawings. Referring to FIG. 1, an embodiment of a composite dipole antenna device 10 according to the present invention includes a plurality of dipole antennas 12, 14, 16, 18 and 20 each adapted to different frequency bands, and each dipole antenna is configured. By supplying electric power to the antenna element, that is, the element through the power supply unit 42 and applying a voltage, for example, a broadband wireless signal can be transmitted and received. Note that portions not directly related to understanding the present invention are not shown and redundant description is avoided.

  The composite dipole antenna device 10 is provided in a radio signal transmission / reception device, a monitoring device, a test device, and the like, and is connected to these devices via a power feeding unit 42. The vicinity of the portion 42 can be provided to be rotatable about an axis.

  As shown in FIG. 1, the composite dipole antenna device 10 of the present embodiment is configured to have a shape extending from one side to the other, for example, a rectangular parallelepiped shape. It may be configured to extend. In FIG. 1, the composite dipole antenna device 10 is configured to extend in the horizontal direction. However, in consideration of the rotation of the device 10 itself, the extending direction is not limited to the horizontal direction. However, in the following description, the description will be made assuming that it extends in the horizontal direction for the sake of simplicity. In FIG. 1, the dotted line and the alternate long and short dash line are included so that the arrangement and shape of the dipole antenna and its elements in the apparatus 10 can be easily understood, but these are not actual components.

  In addition, the composite dipole antenna device 10 of the present embodiment is configured to include a power feeding unit 42 at the center and to bundle a plurality of dipole antennas 12 to 20 near the power feeding unit 42. In the present embodiment, the composite dipole antenna device 10 is configured to include a plurality of dipole antennas 12 to 20 each adapted to a different frequency band, and can effectively respond to a wideband radio signal. In order to react particularly effectively to a frequency band, the same dipole antenna that matches that frequency band may be included in duplicate.

  In the composite dipole antenna device 10 of the present embodiment, the plurality of dipole antennas 12, 14, 16, 18 and 20 are respectively a pair of elements 22 and 32, 24 and 34, 26 and 36, 28 and 38, and 30 and Consists of 40. Each dipole antenna is configured by arranging the pair of elements symmetrically with respect to the power feeding section 42, for example, point-symmetrically. FIG. 2 is a cross-sectional view indicated by a one-dot chain line in FIG. 1, that is, a cross-sectional view in the short direction of the rectangular parallelepiped shape of the apparatus 10, and shows an arrangement example of elements 22, 24, 26, 28 and The elements 32, 34, 36, 38 and 40 arranged symmetrically are also arranged in the same way.

  In FIG. 1, a plurality of dipole antennas 12 to 20 are provided in the composite dipole antenna device 10 so as to extend in the extending direction of the device 10, for example, in the horizontal direction, and fit in the rectangular parallelepiped shape of the device 10. However, the present invention is not limited to the horizontal direction and the rectangular parallelepiped shape, and the dipole antenna elements may be arranged at intervals so as not to interfere with each other.

  In this embodiment, the elements 22 to 40 are linear or rod-shaped conductors, from one end corresponding to the fixed end of the element, that is, the starting end, to the other end corresponding to the free end of the element, that is, the end. And extending to have a longitudinal axis.

  The elements 22 to 40 have a main body part extending in the extending direction of the apparatus 10, and the main body part may be directly connected to the power supply part 42, and the power supply part 42 via the power supply connection part. May be connected. For example, as shown in FIGS. 1 and 2, the main parts of the elements 24 to 30 and 34 to 40 are connected to the power feeding part 42 via the power feeding connecting part extending perpendicularly to the extending direction of the device 10. Is done. The power supply connecting portion of the present embodiment is formed so as to extend perpendicularly to the extending direction of the device 10, but may be formed in other shapes as long as the space between the main portions can be provided. In the following description, the main part may be referred to as an element.

  In the present embodiment, the main portions of the elements 22 to 40 are formed by arranging conductors within a predetermined two-dimensional plane, for example, within a predetermined rectangular range as shown in FIGS. In particular, the conductor is formed on the side thereof, but the conductor is not limited to the rectangular shape but may be arranged in another two-dimensional or three-dimensional shape.

  In addition, the elements 22 to 40 are formed by changing the length of the conductor according to the frequency band to be adapted for each of the plurality of dipole antennas 12, 14, 16, 18, and 20, and each pair of elements is the same as each other. It is formed with a conductor of length and shape. The pair of elements of the present embodiment may be formed with the same length and shape so as to function as a dipole antenna, that is, formed with substantially the same length and shape. In this way, by changing the element length for each dipole antenna, the plurality of dipole antennas can be adapted to different frequency bands, and the composite dipole antenna device 10 can effectively respond to a broadband radio signal. For example, by forming an element with a longer conductor, it can be configured to resonate more effectively with a radio signal in a lower frequency band.

  In each element, one end corresponding to the fixed end of the conductor, that is, the starting point of the conductor is arranged at the starting end of the element, and the element is formed by extending the conductor toward the end of the element. In this embodiment, the main part of the element in at least one dipole antenna is formed so as to be placed on a predetermined two-dimensional plane by bending the conductor. Therefore, the other end corresponding to the free end of the conductor, that is, the end point of the conductor is not limited to the end of the element, and may be arranged between the start and end of the element, for example, reaching the end of the element. It may be arranged to return to the starting end direction from before or before reaching the terminal end.

  In the present embodiment, by applying an element formed by bending a conductor in this way, at least two or more dipole antennas 14, 16, 18 and 20 are connected to a suitable frequency band, that is, the length of the conductor. Instead, the length from the start end to the end of the element can be made equal. Thus, the device 10 can be reduced in size, and can be configured in a size suitable for a limited place such as a shield room to be arranged.

  In the apparatus 10, the dipole antenna may be configured by a pair of elements having only one end point of the conductor, but at least one dipole antenna branches the conductor into a plurality of divided conductors and has a plurality of end points. The plurality of divided conductors are formed in different lengths so that a plurality of paths passing through the respective divided conductors are adapted to different frequency bands.

  For example, as shown in FIG. 3, the elements 22 and 32 are formed by arranging the end point of the conductor at the end of the element without bending the conductor. Also, as shown in FIGS. 4 and 5, the elements 24 and 34 and 26 and 36 are formed by bending the conductor at the end of the element and arranging the end point of the conductor at the end of the element. An element having only one conductor end point, such as these elements, is referred to herein as a single end point element.

  Further, in this embodiment, as shown in FIGS. 6 and 7, the elements 28 and 38, and 30 and 40 are divided into two ends by dividing the conductor, that is, the first end point and the second end point. Formed. An element having a plurality of conductor end points like these elements is referred to herein as a multi-end point element. In this embodiment, in the conductor of the multi-end point element, the part from the start point to the branch point is referred to as a shared conductor, the part from the branch point to the first end point is referred to as the first divided conductor, and the second point from the branch point to the second point. A portion up to the end point is referred to as a second divided conductor. A path passing through the shared conductor and the first divided conductor is referred to as a first divided path, and a path passing through the shared conductor and the second divided conductor is referred to as a second divided path.

  Such multi-end point elements have different frequency bands by changing the length between the first divided conductor and the second divided conductor, that is, changing the length between the first divided path and the second divided path. Can be configured to fit. For example, a path that passes through one of the plurality of divided conductors is formed to be the longest of the paths that respond to a radio signal in the device 10 so that the path matches the lowest frequency band in the device 10. Can be configured. The plurality of divided conductors may be formed to have different lengths so that suitable frequency bands are not adjacent to each other through a path passing through one divided conductor and a path passing through the other divided conductor.

  As shown in FIG. 6, in multi-endpoint elements 28 and 38, the first split conductor extends toward the end of the element without bending and is formed with the end of the conductor at this end, The second split conductor is formed by extending away from the first split conductor, then extending toward the end of the element, bending at the end, and arranging the end of the conductor at the end.

  Further, as shown in FIG. 7, in the multi-end point elements 30 and 40, the first divided conductor extends toward the end of the element without being bent, and the end point of the conductor is arranged before reaching the end. And the second split conductor extends away from the first split conductor, then extends toward the end of the element, and is bent at the end toward the extension line of the first split conductor. It extends and further extends back in the direction of the branch point on the extension line of the first divided conductor, and the end point of the conductor is arranged before reaching the first divided conductor.

  In this way, the multi-end point elements 28, 30, 38 and 40 result in the first and second end points being close to each other, for example the first or second end point being on the extension of the second or first split conductor. The first and second end points are arranged so that the first or second divided path makes a detour in the range of the overall shape of the element. The traveling directions of the first and second divided paths in the vicinity of are different.

  The main portions of the elements 22 to 40 of the present embodiment are formed by arranging conductors on a two-dimensional plane. In particular, the main portions of the multi-end point elements 28, 30, 38 and 40 are as shown in FIGS. The conductor is arranged in the shape of the letter “C” or the letter “K” on the plane, but the conductor may be arranged in other shapes. The divided conductors may be arranged in three dimensions.

  Further, in the composite dipole antenna device 10, the elements 22 to 40 are provided such that the starting ends thereof are arranged on the power feeding unit 42 side, the starting points of the conductors are connected to the feeding unit 42, and the terminal ends thereof are separated from the feeding unit 42. The pair of elements constituting each dipole antenna may be arranged so that the shape of the conductor is symmetrical with respect to the power feeding portion 42, for example, point-symmetric. The pair of elements of this embodiment may be arranged symmetrically so as to function as a dipole antenna, that is, they are arranged substantially symmetrically.

  In the composite dipole antenna device 10 of the present embodiment, as shown in FIGS. 1 and 2, the elements 22 and 32 are connected to the power feeding portion 42 without having the power feeding connecting portion, and the device passes through the power feeding portion 42. 10 parallel to the extending direction, that is, on the longitudinal axis passing through the center of the rectangular parallelepiped shape of the device 10. The elements 24 to 30 and 34 to 40 have a power supply connection portion and are connected to the power supply portion 42, and are provided so that their longitudinal axes are parallel to the elements 22 and 32. The device 10 is provided without being overlapped on a surface having a rectangular parallelepiped longitudinal axis. However, the present invention is not limited to these arrangement examples, and the elements 22 to 40 may be arranged so that the longitudinal axis directions of some or all of the elements are different. For example, only some of the elements have the longitudinal axis thereof. It may be provided in parallel with the extending direction of the device 10, that is, it may be arranged so that the extension line to the end of the longitudinal axis of each element does not intersect.

  Further, the length and shape of the conductors of the elements 22 to 40 and the inclination with respect to the power feeding unit 42 may be selected and designed in advance so that the plurality of dipole antennas 12 to 20 can be adapted to different desired frequency bands. . In addition, the conductor length and shape of the elements 22 to 40 and the inclination with respect to the power feeding part 42 are adjusted in consideration of the interaction between the elements after arranging the plurality of dipole antennas 12 to 20 in the composite dipole antenna device 10. Good.

  Next, a specific example of the composite dipole antenna device 10 in the present embodiment will be described with reference to the graph of FIG.

  The device 10 is configured in the same manner as in the above embodiment, and in this specific example, in particular, in a rectangular parallelepiped shape having a longitudinal axis of about 4 m and a cross section perpendicular to the longitudinal axis being a square of 1 m square. It is configured to include five dipole antennas 12, 14, 16, 18 and 20, and a power feeding unit 42. The feeding section 42 may be 1 cm wide and 18 cm long, and the elements 22 to 40 of each dipole antenna may be formed of a conductor having a width of 1 cm.

  In the device 10, the dipole antennas 12, 14, 16, 18 and 20 are adapted to higher frequency bands in that order, that is, the elements 22 and 24 of the dipole antenna 12 are formed of the shortest conductor, and the elements of the dipole antenna 20 30 and 40 are formed with the longest conductors.

  As shown in FIG. 3, the elements 22 and 32 of the dipole antenna 12 have a length from the start end to the end, that is, the length of the longitudinal axis is 67 cm, and are formed without being bent by a conductor having the same length.

  As shown in FIG. 4, the main parts of the elements 24 and 34 of the dipole antenna 14 have conductors arranged on the sides of a rectangle having a long axis and a short axis of 200 cm and 20 cm, respectively, and a conductor having a length of 220 cm. Is bent at a right angle at the end, and the end point of the conductor is arranged at the end of the element.

  In addition, as shown in FIG. 5, the main portions of the elements 26 and 36 of the dipole antenna 16 have conductors arranged on rectangular sides having a long axis and a short axis length of 200 cm and 57 cm, respectively, and a length of 257 cm. The conductor is bent at a right angle at the end, and the end point of the conductor is arranged at the end of the element.

  Further, as shown in FIG. 6, the main portions of the elements 28 and 38 of the dipole antenna 18 have conductors arranged on rectangular sides with the lengths of the long axis and the short axis being 200 cm and 45 cm, respectively, and 40 cm from the starting end. The conductor is branched at the position of. In the elements 28 and 38, the first split conductor extends toward the end without being bent from the shared conductor, and is formed at a position 160 cm from the branch point, that is, with the first end point at the end. The second split conductor extends in a direction perpendicular to the shared conductor from the branch point, is bent at a right angle at a position of 45 cm from the branch point, extends toward the terminal end, is positioned 160 cm from the bent position, That is, it is bent at a right angle again at the end and extends toward the first end point, and the second end point is arranged at a position 37 cm from the bent position.

  Further, as shown in FIG. 7, the main portions of the elements 30 and 40 of the dipole antenna 20 have conductors arranged on rectangular sides with the lengths of the long axis and the short axis being 200 cm and 55 cm, respectively, and 90 cm from the starting end. The conductor is branched at the position of. In the elements 30 and 40, the first split conductor extends from the shared conductor toward the end without being bent, and is formed by arranging the first end point at a position 30 cm from the branch point. The second split conductor extends in a direction perpendicular to the shared conductor from the branch point, is bent at a right angle at a position of 55 cm from the branch point, extends toward the end, and is positioned 110 cm from the bent position. That is, it is bent at a right angle again at the end and extends toward the extension line of the first divided conductor, and is bent again at a right angle at a position 55 cm from the bending position and extended toward the first end point. Is formed with a second end point at a position 20 cm from the end.

  According to the dipole antenna 20 having such elements 30 and 40, as shown in FIG. 8, it can be seen that the antenna resonates more effectively with a radio signal in a lower frequency band, that is, a frequency band near 20 MHz. . Further, the composite dipole antenna device 10 of this embodiment also has dipole antennas 12 to 18 adapted to other frequency bands, that is, three dipole antennas 12 to 16 functioning as one dipole by a single end point element. And the two dipole antennas 18 and 20 functioning as two dipoles by the multi-end point element, and can function as seven dipoles. In addition, in the dipole antennas 18 and 20, the multi-end point element that resonates near 20 MHz and 25 MHz resonates even at a harmonic that is three times that, so two more resonance points can be obtained. In addition to the seven resonance points by the minute dipole, more effective resonance can be obtained at nine resonance points in a wide frequency band of 20 to 100 MHz as shown in FIG.

10 Compound dipole antenna device
12 ~ 20 dipole antenna
22 to 40 elements
42 Power supply unit

Claims (8)

Including a plurality of dipole antennas each having a pair of elements;
In a composite dipole antenna device that operates by supplying power to the element via a power feeding unit,
The composite dipole antenna device as a whole has a three-dimensional shape having a plurality of outer surfaces along the extending direction of the device,
In each of the plurality of dipole antennas, the elements are formed of linear or rod-like conductors having substantially the same length and shape as each other, and are arranged substantially symmetrically with respect to the feeding portion.
The conductor is configured to be different in length and adapted to different frequency bands between at least two of the plurality of dipole antennas;
In at least one of the plurality of dipole antennas, the conductor has a plurality of divided conductors branched from each other and having respective end points, and the plurality of divided conductors pass through the respective divided conductors and the end points. Are formed with different lengths so as to adapt to different frequency bands ,
The element in at least two of the plurality of dipole antennas has a main body that is bent within a range including edges on respective outer surfaces of the three-dimensional shape that are adjacent to each other, and the main body is within the range. And a dipole antenna device having at least one end point .   2. The composite dipole antenna device according to claim 1, wherein the at least one dipole antenna is formed so that a path passing through one of the plurality of divided conductors is the longest among paths that react to a radio signal in the apparatus. And the path is configured to be adapted to the lowest frequency band in the apparatus.   2. The composite dipole antenna device according to claim 1, wherein the pair of elements are arranged point-symmetrically with respect to the feeding portion. 2. The composite dipole antenna device according to claim 1 , wherein at least two of the plurality of dipole antennas have a suitable frequency band, that is, a length from a start end to an end of the element regardless of a length of the conductor. A composite dipole antenna device characterized by being configured to be equal to each other. In the composite dipole antenna device according to claim 1, wherein the three-dimensional shape is a rectangular parallelepiped shape,
The composite dipole antenna device, wherein the dipole antenna is provided so that the main portion is disposed on a surface of the rectangular parallelepiped in the longitudinal axis direction. The composite dipole antenna device according to claim 5 , wherein the feeding portion is arranged at a center of the rectangular parallelepiped shape of the device,
At least one of the plurality of dipole antennas is provided in parallel with a longitudinal axis direction of the device through the feeding portion, and a composite dipole antenna device.   2. The composite dipole antenna device according to claim 1, wherein the elements of the dipole antenna are arranged at a distance so as not to interfere with other elements of the dipole antenna. 3.   2. The composite dipole antenna device according to claim 1, wherein the plurality of divided conductors have different lengths such that a frequency band matching a path passing through one split conductor and a path passing through the other split conductor are not adjacent to each other. A composite dipole antenna device characterized by being formed of

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