JP6257401B2 - Antenna device - Google Patents

Description

  The present invention relates to an antenna device using a waveguide.

  Conventionally, in an antenna device for satellite communication or radar, a thin array antenna has been used in order to facilitate mounting on a moving body such as an aircraft, a vehicle, and a satellite. In recent years, there has been an increasing demand for more sophisticated antenna devices, which operate over a wide frequency range (having so-called “broadband characteristics”) and can be used with two orthogonal polarizations (so-called “orthogonal polarization”). An antenna for “wave sharing” is required.

  Conventionally, a so-called “quad ridge horn antenna” has been used as one of orthogonally polarized antennas having broadband characteristics (see, for example, Patent Document 1).

  A conventional quad ridge horn antenna is configured using a rectangular waveguide having a square cross section. In this rectangular waveguide, an opening at one end is closed with a plate-like conductor (hereinafter referred to as “short-circuit conductor wall”), and is electrically short-circuited. In addition, on the inner surface of the four side walls (hereinafter referred to as “first side wall”, “second side wall”, “third side wall”, and “fourth side wall”) of the rectangular waveguide, the longitudinal direction is along the tube axis direction. Ridge-shaped protrusions (hereinafter referred to as “first ridge”, “second ridge”, “third ridge”, and “fourth ridge”) are provided. The rectangular waveguide and the first to fourth ridges constitute a so-called “quad ridge waveguide”.

  A first feeding probe is provided between the first ridge and the third ridge facing each other. A second feeding probe is provided between the second ridge and the fourth ridge facing each other. The first power supply probe and the second power supply probe are provided in directions orthogonal to each other with respect to the tube axis direction of the rectangular waveguide. The quad ridge waveguide, the first feeding probe, and the second feeding probe constitute an antenna unit.

  The first power supply probe is connected to a first power supply circuit provided outside the quadridge waveguide. The second power supply probe is connected to a second power supply circuit provided outside the quadridge waveguide.

Regarding the operation of the conventional quad ridge horn antenna configured as described above, the operation as a transmitting antenna will be described.
The high-frequency current input from the first power supply circuit to the first power supply probe is converted into a first radio wave propagating in the quad ridge waveguide. The first radio wave reaching the opening of the quadridge waveguide is radiated to the external space of the antenna unit. In addition, the high-frequency current input from the second power supply circuit to the second power supply probe is converted into a second radio wave propagating through the quadridge waveguide. The second radio wave reaching the opening of the quadridge waveguide is radiated to the external space of the antenna unit.

  At this time, since the first feeding probe and the second feeding probe are provided in directions orthogonal to each other with respect to the tube axis direction, the direction of the electromagnetic field distribution of the first radio wave propagating in the quad ridge waveguide tube And the direction of the electromagnetic field distribution of the second radio wave are perpendicular to the tube axis direction. For this reason, the direction of the polarization of the first radio wave radiated from the opening and the direction of the polarization of the second radio wave are perpendicular to the tube axis direction. In this way, orthogonal polarization sharing is realized.

  In the quad ridge horn antenna, the distance along the tube axis direction between the short-circuit conductor wall and the first feeding probe (hereinafter referred to as “first spacing”) is the output impedance of the first feeding circuit and the input impedance of the antenna section. This is one of the design parameters for matching (so-called “impedance matching”). In addition, an interval along the tube axis direction between the short-circuit conductor wall and the second feeding probe (hereinafter referred to as “second spacing”) is one of the design parameters for impedance matching between the second feeding circuit and the antenna unit. is there.

  Usually, a quad ridge horn antenna has a line-symmetric structure with respect to the tube axis of a rectangular waveguide. Therefore, in order to achieve both impedance matching between the first feeding circuit and the antenna unit and impedance matching between the second feeding circuit and the antenna unit, the first feeding probe and the second feeding probe are mutually connected in the tube axis direction. The first interval and the second interval are set to be approximately equal to each other.

Japanese Patent Laid-Open No. 9-162631

  In general, in an array antenna, in order to prevent a grating lobe from being generated in a visible region, antenna elements are arranged with an interval shorter than a wavelength at an operating frequency. In order to realize a thin array antenna, it is preferable to provide a feeding circuit for supplying a high-frequency current to each antenna element in the gap between the antenna elements, not on the back surface of each antenna element.

  However, when an array antenna is configured using a conventional quad ridge horn antenna as an antenna element, the cross-sectional dimension of the quad ridge waveguide is large, so the width of the gap between the antenna elements is narrow. As a result, there has been a problem that the width of the gap portion in which the power feeding circuit connected to each power feeding probe is not sufficiently secured. Furthermore, since it is necessary to provide the first power supply probe and the second power supply probe close to each other in the tube axis direction, the power supply circuits connected to each power supply probe may physically interfere with each other to provide the power supply circuit. There was a problem that became difficult.

  The present invention has been made in order to solve the above-described problems. The impedance matching between the two feeding circuit units and the antenna unit is performed with an interval along the tube axis direction between the two feeding probes as an arbitrary interval. An object of the present invention is to provide an orthogonal polarization shared antenna device that can take

The antenna device according to the present invention communicates with the short-circuited waveguide portion having one end electrically short-circuited, the other end of the short-circuited waveguide portion and the one-end portion, and 1 along the longitudinal direction of the inner surface portion. The double ridge waveguide portion in which the first ridges of the pair are arranged to face each other, the other end portion of the double ridge waveguide portion and the one end portion communicate with each other, and the length of the inner surface portion is continuous with the first ridge. A quad-ridge waveguide section having a pair of second ridges opposed to each other along the direction and having a pair of third ridges arranged opposite to the inner surface between the second ridges; A first feeding probe that is disposed at an end portion of the wave tube portion on the short-circuiting waveguide portion side and feeds power between the opposed first protrusions, and a double ridge waveguide of the quad ridge waveguide portion. It is arranged at an end of the tube portion, and a second feed probe for feeding between the third protrusion facing the second feed Frequency Rejection in a radio wave propagation mode that is input and output by the lobes, so that a frequency higher than the frequency of the radio wave, is what is set in a double ridge waveguide section.

  Further, the antenna device of the present invention is provided with a short-circuited waveguide portion in which one end portion is electrically short-circuited, and one end portion communicated with the other end portion of the short-circuited waveguide portion, and the longitudinal direction of the inner surface portion. A double ridge waveguide portion having a pair of first ridges arranged opposite to each other, and one end portion communicating with the other end portion of the double ridge waveguide portion, and continuous with the first ridge portion. As described above, the quad ridge waveguide has a pair of second ridges arranged to face each other along the longitudinal direction of the inner surface portion, and a pair of third ridges arranged to face the inner surface portion between the second ridges. A first dielectric substrate provided between the tube portion, the short-circuited waveguide portion and the double ridge waveguide portion, and a first power supply provided between the first protrusions provided on the first dielectric substrate and opposed to each other. A line, a second dielectric substrate provided between the double ridge waveguide portion and the quad ridge waveguide portion, and a second dielectric substrate And a second feed line that feeds power between the opposing third protrusions, and the cutoff frequency in the propagation mode of the radio wave input and output by the second feed line is higher than the frequency of the radio wave. Thus, it is set in the double ridge waveguide section.

  According to the present invention, an orthogonally polarized antenna device capable of matching impedance between the two power supply circuit units and the antenna unit is obtained by setting an interval along the tube axis direction between the two power supply probes as an arbitrary interval. be able to.

It is a disassembled perspective view of the short circuit waveguide part and double ridge waveguide part of Embodiment 1 of this invention. It is a disassembled perspective view of the quadridge waveguide part of Embodiment 1 of this invention. It is explanatory drawing which shows the structure seen from the opening part of the antenna device of Embodiment 1 of this invention. (A) is explanatory drawing which shows the structure seen from the A-A 'cross section of the antenna apparatus shown to FIG. 2A. (B) is explanatory drawing which shows the structure seen from the B-B 'cross section of the antenna apparatus shown to FIG. 2A. It is explanatory drawing which shows the structure seen from the opening part of the other antenna apparatus of Embodiment 1 of this invention. (A) is explanatory drawing which shows the structure seen from the A-A 'cross section of the antenna apparatus shown to FIG. 3A. (B) is explanatory drawing which shows the structure seen from the B-B 'cross section of the antenna apparatus shown to FIG. 3A. It is explanatory drawing which shows the structure seen from the opening part of the other antenna apparatus of Embodiment 1 of this invention. (A) is explanatory drawing which shows the structure seen from the A-A 'cross section of the antenna apparatus shown to FIG. 4A. (B) is explanatory drawing which shows the structure seen from the B-B 'cross section of the antenna apparatus shown to FIG. 4A. It is explanatory drawing which shows the structure seen from the opening part of the other antenna apparatus of Embodiment 1 of this invention. (A) is explanatory drawing which shows the structure seen from the A-A 'cross section of the antenna apparatus shown to FIG. 5A. (B) is explanatory drawing which shows the structure seen from the B-B 'cross section of the antenna apparatus shown to FIG. 5A. It is explanatory drawing which shows the structure seen from the opening part of the other antenna apparatus of Embodiment 1 of this invention. (A) is explanatory drawing which shows the structure seen from the A-A 'cross section of the antenna apparatus shown to FIG. 6A. (B) is explanatory drawing which shows the structure seen from the B-B 'cross section of the antenna apparatus shown to FIG. 6A. It is a disassembled perspective view of the short circuit waveguide part and double ridge waveguide part of Embodiment 2 of this invention. It is a disassembled perspective view of the quadridge waveguide part of Embodiment 2 of this invention. It is explanatory drawing which shows the structure seen from the opening part of the antenna device of Embodiment 2 of this invention. (A) is explanatory drawing which shows the structure seen from the A-A 'cross section of the antenna apparatus shown to FIG. 8A. (B) is explanatory drawing which shows the structure seen from the B-B 'cross section of the antenna apparatus shown to FIG. 8A. It is explanatory drawing which shows the structure seen from the opening part of the other antenna apparatus of Embodiment 2 of this invention. (A) is explanatory drawing which shows the structure seen from the A-A 'cross section of the antenna apparatus shown to FIG. 9A. (B) is explanatory drawing which shows the structure seen from the B-B 'cross section of the antenna apparatus shown to FIG. 9A.

Embodiment 1 FIG.
With reference to FIG. 1A, FIG. 1B, FIG. 2A, and FIG. 2B, the antenna apparatus of Embodiment 1 of this invention is demonstrated.
In the figure, reference numeral 1 denotes a first waveguide. The first waveguide 1 is a rectangular waveguide having a square cross section. The opening at one end of the first waveguide 1 is closed by a short-circuit conductor wall 4 made of a plate-like conductor and is electrically short-circuited. The first waveguide 1 and the short-circuit conductor wall 4 constitute a short-circuit waveguide portion.

  A second waveguide 2 is provided in communication with the first waveguide 1. The second waveguide 2 is a rectangular waveguide that is integral with the first waveguide 1. A pair of ridges whose longitudinal direction is along the tube axis direction (z direction in the figure) of the second waveguide 2 at the mutually facing portions of the inner surfaces of the sidewalls 21a and 21b facing each other of the second waveguide 2 The first protrusions (first ridge portions) 22a and 22b are provided. The second waveguide 2 and the first ridge portions 22a and 22b constitute a double ridge waveguide portion.

  In general, in a waveguide, each form of electromagnetic field distribution of radio waves propagating in the tube is referred to as “propagation mode”. The double ridge waveguide section is adjusted for each propagation by adjusting the dimensions of the second waveguide 2 and the first ridge sections 22a and 22b in the direction (x direction and y direction in the figure) orthogonal to the tube axis direction. The value of the lowest frequency (so-called “cutoff frequency”) at which radio waves propagate in the mode changes.

  A first probe insertion hole 7 is provided through the side wall 21b and the first ridge portion 22b of the double ridge waveguide portion in a direction perpendicular to the tube axis direction (y direction in the figure). A first feeding probe 5 made of a rod-like conductor is inserted along the axis of the first probe insertion hole 7. One end portion 51 of the first power supply probe 5 is provided between the first ridge portions 22a and 22b.

  A third waveguide 3 is provided in communication with the second waveguide 2. The third waveguide 3 is a rectangular waveguide integrated with the first waveguide 1 and the second waveguide 2. The longitudinal direction is continuous with the first ridge portions 22a and 22b at the mutually opposing portions of the inner surface portions of the mutually opposite side walls 31a and 31b of the third waveguide 3, and the longitudinal direction is the tube axis direction of the third waveguide 3 ( A pair of ridge-shaped second protrusions (second ridge portions) 32a and 32b are provided along the z direction in the drawing. The second ridge portions 32 a and 32 b have planar tapered surfaces 34 a and 34 b that are inclined toward the opening 35 of the third waveguide 3.

  A pair of ridge-shaped third ridges whose longitudinal direction is along the tube axis direction of the third waveguide 3 at the mutually facing portions of the inner surfaces of the side walls 31c and 31d facing each other of the third waveguide 3 ( (Third ridge portion) 33a and 33b are provided. The third ridge portions 33 a and 33 b have planar tapered surfaces 34 c and 34 d that are inclined toward the opening 35 of the third waveguide 3. The third ridge 3, the second ridges 32a and 32b, and the third ridges 33a and 33b constitute a quad ridge waveguide.

  A second probe insertion hole 8 is provided through the side wall 31d and the third ridge portion 33b of the quad ridge waveguide portion in a direction (x direction in the drawing) perpendicular to the tube axis direction. A second power feeding probe 6 made of a rod-shaped conductor is inserted along the axis of the second probe insertion hole 8. One end portion 61 of the second power feeding probe 6 is provided between the third ridge portions 33a and 33b.

  The antenna unit 100 includes the short-circuited waveguide unit, the double ridge waveguide unit, the quad ridge waveguide unit, the first probe insertion hole 7, the first feeding probe 5, the second probe insertion hole 8, and the second feeding probe 6. Is configured.

  The other end 52 of the first power supply probe 5 is electrically connected to the first power supply circuit unit 200 provided outside the double ridge waveguide unit. The other end 62 of the second power supply probe 6 is electrically connected to a second power supply circuit unit 300 provided outside the quadridge waveguide unit. The first feeding circuit unit 200 and the second feeding circuit unit 300 are, for example, transmission lines (for example, filled with an insulator between a tubular outer conductor and an inner conductor provided along the axis of the outer conductor). So-called “coaxial line”).

Next, the operation of the antenna device 400 configured as described above will be described as an operation as a transmission antenna.
The high-frequency current input from the first power supply circuit unit 200 to the first power supply probe 5 is converted into a radio wave having a frequency corresponding to the frequency of the high-frequency current (hereinafter referred to as “first radio wave”), and a double ridge waveguide To the output. The output first radio wave propagates through the double ridge waveguide section in a predetermined propagation mode (hereinafter referred to as “first propagation mode”) that propagates through the double ridge waveguide section, and enters the quad ridge waveguide section. Is output.

  Here, the quadridge waveguide portion is configured to propagate radio waves in the first propagation mode. Therefore, the first radio wave output from the double ridge waveguide section propagates through the quad ridge waveguide section and reaches the opening 35 of the third waveguide 3. The first radio wave reaching the opening 35 is radiated to the external space of the antenna unit 100.

  At this time, the electromagnetic field distribution in the first propagation mode is an electromagnetic field distribution in which the direction of the electric field is along the y direction in the figure. For this reason, the main polarization of the first radio wave radiated from the opening 35 is a polarization component in the direction along the y direction.

  Further, the length L1 of the first waveguide 1 in the tube axis direction, the distance L3 along the tube axis direction between the short-circuit conductor wall 4 and the first feed probe, the structure of the first probe insertion hole 7, and the first feed probe 5 By adjusting the shape or the like, the input impedance of the antenna unit 100 can be matched to the output impedance of the first power feeding circuit unit 200 (so-called “impedance matching”).

  Next, the high frequency current input from the second power supply circuit unit 300 to the second power supply probe 6 is converted into a radio wave having a frequency corresponding to the frequency of the high frequency current (hereinafter referred to as a “second radio wave”), and the quad ridge. Output to the waveguide section. The output second radio wave propagates through the quadridge waveguide section in a predetermined propagation mode (hereinafter referred to as “second propagation mode”) that propagates through the quadridge waveguide section.

  Here, the double ridge waveguide section is set so that the cutoff frequency of the second propagation mode is higher than the frequency of the second radio wave. As a result, the second radio wave output to the quad ridge waveguide section does not propagate in the direction toward the double ridge waveguide. That is, the second radio wave propagates only in the direction toward the opening 35 of the third waveguide 3.

  The second radio wave reaching the opening 35 is radiated to the external space of the antenna unit 100. At this time, the electromagnetic field distribution in the second propagation mode is an electromagnetic field distribution in which the direction of the electric field is along the x direction in the figure. For this reason, the main polarization of the second radio wave radiated from the opening 35 is a polarization component in the direction along the x direction.

  As a result, the first radio wave and the second radio wave are radio waves in which the directions of the main polarizations are orthogonal to each other, and orthogonal polarization sharing can be realized.

  Further, since the second radio wave does not propagate in the direction toward the double ridge waveguide portion, the impedance characteristic of the antenna unit 100 with respect to the second feeder circuit unit 300 is the length L2 of the second waveguide 2 in the tube axis direction. Is almost unaffected. Therefore, regardless of the value of the length L2, the distance L4 along the tube axis direction between the short-circuit conductor wall 4 and the second power supply probe 6, the structure of the second probe insertion hole 8, the shape of the second power supply probe 6, and the like are adjusted. Thus, impedance matching between the second power feeding circuit unit 300 and the antenna unit 100 can be achieved.

  That is, even if the length L2 of the double ridge waveguide portion in the tube axis direction is increased and the interval (L4-L3) along the tube axis direction between the first power supply probe 5 and the second power supply probe 6 is increased. Both impedance matching between the first power feeding circuit unit 200 and the antenna unit 100 and impedance matching between the second power feeding circuit unit 300 and the antenna unit 100 can be achieved.

Note that the antenna device 400 operates in the same manner as when operating as a transmitting antenna when operating as a receiving antenna due to so-called “antenna reversibility”.
That is, a radio wave having a polarization component in the y direction irradiated to the opening 35 of the third waveguide 3 as a main polarization is transmitted through the quad ridge waveguide portion and the double ridge waveguide portion in the first propagation mode. Propagate. This radio wave is converted into a high-frequency current by the first power supply probe 5. This high frequency current is output to the first power feeding circuit unit 200.
In addition, the radio wave having the polarization component in the x direction irradiated to the opening 35 of the third waveguide 3 as the main polarization propagates through the quadridge waveguide portion in the second propagation mode. This radio wave is converted into a high-frequency current by the second feeding probe 6. This high frequency current is output to the second power feeding circuit unit 300. At this time, radio waves in the second propagation mode do not propagate to the double ridge waveguide section.

As described above, in the antenna device 400 according to the first embodiment of the present invention, the short-circuited waveguide portion, the double ridge waveguide portion, and the quad ridge waveguide portion are provided in communication. The first ridge probe 5 is provided in the double ridge waveguide section, and the second feed probe 6 is provided in the quad ridge waveguide section. Further, the double ridge waveguide section is set so that the cutoff frequency of the second propagation mode is higher than the frequency of the second radio wave.
As a result, the impedance matching between the first feeding circuit unit 200 and the antenna unit 100 can be performed with an interval (L4-L3) along the tube axis direction between the first feeding probe 5 and the second feeding probe 6 as an arbitrary interval, Both the impedance matching between the 2-feed circuit unit 300 and the antenna unit 100 can be achieved.

  As a result, in the array antenna formed by arranging a plurality of antenna units 100, the first feeding circuit unit 200 and the second feeding circuit unit 300 do not physically interfere with each other, so that the width of the gap between the antenna units 100 is reduced. It is possible to realize a small array antenna with a narrowed area.

  In addition, the shape of the cross section of the 1st waveguide 1, the 2nd waveguide 2, and the 3rd waveguide 3 is not limited to square shape. The first waveguide 1, the second waveguide 2, and the third waveguide 3 are configured using a rectangular waveguide having a rectangular cross section or a circular waveguide having a circular cross section. It is good also as what you did.

  The shapes of the second ridge portions 32a and 32b and the third ridge portions 33a and 33b are not limited to the shapes having the planar tapered surfaces 34a to 34d shown in FIGS. 1B and 2B. As shown in FIG. 3B, a shape having a curved tapered surface inclined according to an exponential function may be used. As shown in FIG. 4B, the shape may have a stepped tapered surface. As shown in FIG. 5B, the shape may not have a tapered surface.

  Further, as shown in FIG. 6B, a pair of fourth ridge portions 11a and 11b continuous with the first ridge portions 22a and 22b are provided on the inner surface portion of the first waveguide 1, so that the first waveguide 1, The double ridge waveguide portion may be configured by the two waveguides 2, the fourth ridge portions 11a and 11b, and the first ridge portions 22a and 22b.

Embodiment 2. FIG.
With reference to FIG. 7A, FIG. 7B, FIG. 8A and FIG. 8B, an antenna device in which the first feeding probe and the second feeding probe are constituted by a conductive foil (so-called “strip conductor”) provided on a dielectric substrate will be described. .
In the figure, reference numeral 1 denotes a first waveguide. The first waveguide 1 is a rectangular waveguide having a square cross section. The opening at one end of the first waveguide 1 is closed by a short-circuit conductor wall 4 made of a plate-like conductor and is electrically short-circuited. The first waveguide 1 and the short-circuit conductor wall 4 constitute a short-circuit waveguide portion.

  A second waveguide 2 is provided so as to communicate with the first waveguide 1. The second waveguide 2 is a rectangular waveguide having the same cross-sectional shape as the first waveguide 1. A pair of ridges whose longitudinal direction is along the tube axis direction (z direction in the figure) of the second waveguide 2 at the mutually facing portions of the inner surfaces of the sidewalls 21a and 21b facing each other of the second waveguide 2 The first protrusions (first ridge portions) 22a and 22b are provided. The second waveguide 2 and the first ridge portions 22a and 22b constitute a double ridge waveguide portion.

  The double ridge waveguide portion configured in this way has dimensions in the direction (x direction and y direction in the drawing) orthogonal to the tube axis direction of the second waveguide 2 and the first ridge portions 22a and 22b. By adjusting, the value of the cut-off frequency of each propagation mode is changed.

  A first dielectric substrate 7 a is provided between the first waveguide 1 and the second waveguide 2. The surface 71a of the first dielectric substrate 7a faces the first ridge portions 22a and 22b through the gap portions 72a and 72b. On the surface 71a, a first power feed made of a linear conductor foil is provided so that the longitudinal direction is along the direction orthogonal to the tube axis direction (the y direction in the figure) and between the first ridge portions 22a and 22b. A track 5a is provided.

  A third waveguide 3 is provided so as to communicate with the second waveguide 2. The third waveguide 3 is a rectangular waveguide whose cross-sectional shape is the same as that of the first waveguide 1 and the second waveguide 2. The longitudinal direction of the third waveguide 3 is the tube axis direction of the third waveguide 3 so as to be continuous with the first ridge portions 22a and 22b at the mutually facing portions of the inner surfaces of the side walls 31a and 31b facing each other. A pair of ridge-shaped second ridges (second ridge portions) 32a and 32b are provided along the (z direction in the figure). The second ridge portions 32 a and 32 b have planar tapered surfaces 34 a and 34 b that are inclined toward the opening 35 of the third waveguide 3.

  A pair of ridge-shaped third ridges whose longitudinal direction is along the tube axis direction of the third waveguide 3 at the mutually facing portions of the inner surfaces of the side walls 31c and 31d facing each other of the third waveguide 3 ( (Third ridge portion) 33a and 33b are provided. The third ridge portions 33 a and 33 b have planar tapered surfaces 34 c and 34 d that are inclined toward the opening 35 of the third waveguide 3. The third ridge 3, the second ridges 32a and 32b, and the third ridges 33a and 33b constitute a quad ridge waveguide.

  A second dielectric substrate 8 a is provided between the second waveguide 2 and the third waveguide 3. The back surface 81a of the second dielectric substrate 8a is opposed to the first ridge portions 22a and 22b via the gap portions 82a and 82b. The surface 83a of the second dielectric substrate 8a faces the second ridge portions 32a and 32b via the gap portions 84a and 84b. The surface 83a is opposed to the third ridges 33a and 33b via the gaps 85a and 85b. Further, the surface 83a is formed of a linear conductor foil such that the longitudinal direction is along the direction (x direction in the figure) perpendicular to the tube axis direction and is interposed between the third ridge portions 33a and 33b. Two feed lines 6a are provided.

  The antenna unit 100a includes a short-circuited waveguide unit, a double ridge waveguide unit, a quad ridge waveguide unit, a first dielectric substrate 7a, a first feed line 5a, a second dielectric substrate 8a, and a second feed line 6a. Is configured.

  One end of the first feed line 5a is electrically connected to a first feed circuit portion 200a provided outside the double ridge waveguide portion. One end of the second feed line 6a is electrically connected to a second feed circuit unit 300a provided outside the quadridge waveguide unit. The first power supply circuit unit 200a and the second power supply circuit unit 300a are configured by, for example, transmission lines (so-called “strip lines”) in which a linear conductive foil is provided on the surface or inside of a dielectric substrate. Or it is comprised with the transmission line (what is called a "suspended strip line") which provides a strip line in the hollow part of a tubular conductor.

Next, the operation of the antenna device 400a configured as described above will be described as an operation as a transmission antenna.
The high-frequency current input from the first power supply circuit unit 200a to the first power supply line 5a is converted into a radio wave having a frequency corresponding to the frequency of the high-frequency current (hereinafter referred to as “first radio wave”), and a double ridge waveguide To the output. The output first radio wave propagates through the double ridge waveguide section in a predetermined propagation mode (hereinafter referred to as “first propagation mode”) that propagates through the double ridge waveguide section, and enters the quad ridge waveguide section. Is output.

  The quadridge waveguide portion is configured to propagate radio waves in the first propagation mode. Therefore, the first radio wave output from the double ridge waveguide section propagates through the quad ridge waveguide section and reaches the opening 35 of the third waveguide 3. The 1st electromagnetic wave which reached the opening part 35 is radiated | emitted to the external space of the antenna part 100a.

  At this time, the electromagnetic field distribution in the first propagation mode is an electromagnetic field distribution in which the direction of the electric field is along the y direction in the figure. For this reason, the main polarization of the first radio wave radiated from the opening 35 is a polarization component in the direction along the y direction.

  Further, the length L1 of the first waveguide 1 in the tube axis direction, the length, thickness and shape of the first feed line 5a, and the tube axis direction between the first feed line 5a and the first ridge portions 22a and 22b. By adjusting the distance L3 and the like along the impedance, impedance matching between the first feeding circuit portion 200a and the antenna portion 100a can be achieved.

  Next, the high-frequency current input from the second power supply circuit unit 300a to the second power supply line 6a is converted into a radio wave having a frequency corresponding to the frequency of the high-frequency current (hereinafter referred to as “second radio wave”), and the quad ridge. Output to the waveguide section. The output second radio wave propagates through the quadridge waveguide section in a predetermined propagation mode (hereinafter referred to as “second propagation mode”) that propagates through the quadridge waveguide section.

  Here, the double ridge waveguide section is set so that the cutoff frequency of the second propagation mode is higher than the frequency of the second radio wave. As a result, the second radio wave output to the quad ridge waveguide section does not propagate in the direction toward the double ridge waveguide section. That is, the second radio wave propagates only in the direction toward the opening 35 of the third waveguide 3.

  The second radio wave reaching the opening 35 is radiated to the external space of the antenna unit 100a. At this time, the electromagnetic field distribution in the second propagation mode is an electromagnetic field distribution in which the direction of the electric field is along the x direction in the figure. For this reason, the main polarization of the second radio wave radiated from the opening 35 is a polarization component in the direction along the x direction.

  As a result, the first radio wave and the second radio wave are radio waves in which the directions of the main polarizations are orthogonal to each other, and orthogonal polarization sharing can be realized.

  Further, since the second radio wave does not propagate in the direction toward the double ridge waveguide section, the impedance characteristic of the antenna section 100a with respect to the second feeder circuit section 300a is the length L2 of the second waveguide 2 in the tube axis direction. Is almost unaffected. Therefore, regardless of the value of the length L2, the thickness, length, and shape of the second feed line 6a, the distance L4 along the tube axis direction between the second feed line 6a and the third ridge portions 33a, 33b, etc. By adjusting, impedance matching between the second power feeding circuit unit 300a and the antenna unit 100a can be achieved.

  That is, even if the length L2 of the double ridge waveguide portion in the tube axis direction is increased and the interval along the tube axis direction between the first feed line 5a and the second feed line 6a is increased, the first feed circuit Both impedance matching between the unit 200a and the antenna unit 100a and impedance matching between the second feeding circuit unit 300a and the antenna unit 100a can be achieved.

Note that the antenna device 400a operates in the same manner as when operating as a transmitting antenna when operating as a receiving antenna due to so-called “antenna reversibility”.
That is, a radio wave having a polarization component in the y direction irradiated to the opening 35 of the third waveguide 3 as a main polarization is transmitted through the quad ridge waveguide portion and the double ridge waveguide portion in the first propagation mode. Propagate. This radio wave is converted into a high-frequency current by the first feed line 5a. This high-frequency current is output to the first power feeding circuit unit 200a.
In addition, the radio wave having the polarization component in the x direction irradiated to the opening 35 of the third waveguide 3 as the main polarization propagates through the quadridge waveguide portion in the second propagation mode. This radio wave is converted into a high-frequency current by the second feed line 6a. This high frequency current is output to the second power feeding circuit unit 300a. At this time, radio waves in the second propagation mode do not propagate to the double ridge waveguide section.

As described above, the antenna device 400a according to the second embodiment of the present invention is provided so that the short-circuited waveguide section, the double ridge waveguide section, and the quad ridge waveguide section communicate with each other. Further, the first feed line 5a is provided on the first dielectric substrate 7a provided between the short-circuited waveguide portion and the double ridge waveguide portion. A second feed line 6a is provided on a second dielectric substrate 8a provided between the double ridge waveguide portion and the quad ridge waveguide portion. Further, the double ridge waveguide section is set so that the cutoff frequency of the second propagation mode is higher than the frequency of the second radio wave.
As a result, the impedance matching between the first feeding circuit unit 200a and the antenna unit 100a and the second feeding circuit unit 300a can be performed with an interval along the tube axis direction between the first feeding line 5a and the second feeding line 6a as an arbitrary interval. And impedance matching between the antenna unit 100a and the antenna unit 100a.

  As a result, in the array antenna formed by arranging a plurality of antenna units 100a, the first feeding circuit unit 200a and the second feeding circuit unit 300a do not physically interfere with each other, so the width of the gap between the antenna units 100a It is possible to realize a small array antenna with a narrowed area.

  The first feeder line 5a may be provided inside the first dielectric substrate 7a instead of the surface 71a of the first dielectric substrate 7a. The second feed line 6a may be provided inside the first dielectric substrate 7a instead of the surface 83a of the second dielectric substrate 8a.

  The back surface 81a of the second dielectric substrate 8a may be in contact with the first ridge portions 22a and 22b except for the gap portions 82a and 82b. Except for the gap portions 84a and 84b, the surface 83a of the second dielectric substrate 8a may be in contact with the second ridge portions 32a and 32b.

  Moreover, the shape of the cross section of the 1st waveguide 1, the 2nd waveguide 2, and the 3rd waveguide 3 is not limited to square shape. The first waveguide 1, the second waveguide 2, and the third waveguide 3 are configured using a rectangular waveguide having a rectangular cross section or a circular waveguide having a circular cross section. It is good also as what you did.

  The shapes of the second ridge portions 32a and 32b and the third ridge portions 33a and 33b are not limited to the shapes having the planar tapered surfaces 34a to 34d shown in FIGS. 7B and 8B. Similar to Embodiment 1, a ridge portion having the shape shown in FIG. 3B, FIG. 4B, or FIG. 5B may be used.

  Also, as shown in FIG. 9B, a pair of fourth ridge portions 11a and 11b are provided on the inner surface of the first waveguide 1 so as to be continuous with the first ridge portions 22a and 22b. The double ridge waveguide portion may be configured by the second waveguide 2, the fourth ridge portions 11a and 11b, and the first ridge portions 22a and 22b.

  In the present invention, within the scope of the invention, any combination of the embodiments, or any modification of any component in each embodiment, or omission of any component in each embodiment is possible. .

  DESCRIPTION OF SYMBOLS 1 1st waveguide, 2nd waveguide 3, 3rd waveguide, 4 short-circuit conductor wall, 5 1st electric power feeding probe, 5a 1st electric power feeding line, 6 2nd electric power feeding probe, 6a 2nd electric power feeding line, 7 first probe insertion hole, 7a first dielectric substrate, 8 second probe insertion hole, 8a second dielectric substrate, 11a, 11b fourth ridge part, 21a, 21b side wall, 22a, 22b first ridge part (first 1 ridge), 31a, 31b, 31c, 31d side wall, 32a, 32b second ridge portion (second ridge), 33a, 33b third ridge portion (third ridge), 34a, 34b, 34c, 34d taper Surface, 35 opening, 51 one end, 52 other end, 61 one end, 62 other end, 71a surface, 72a, 72b gap, 81a back, 82a, 82b gap, 83a surface, 84a, 84b gap , 85 , 85b gap, 100, 100a antenna unit, the first power supply circuit portion 200 and 200 a, 300 and 300a second feed circuit part, 400 and 400a antenna device.

Claims (16)

A short-circuited waveguide section in which one end is electrically short-circuited;
A double ridge waveguide portion communicating with the other end portion of the short-circuited waveguide portion through one end portion, and having a pair of first protrusions opposed to each other along the longitudinal direction of the inner surface portion;
A pair of second ridges that communicate with each other through the other end portion of the double ridge waveguide portion and that are arranged opposite to each other along the longitudinal direction of the inner surface portion continuously with the first ridge portion. A quadridge waveguide portion having a pair of third ridges disposed opposite to the inner surface portion between the second ridges,
A first feeding probe that is disposed at an end of the double ridge waveguide part on the short-circuiting waveguide part side and feeds power between the first protrusions facing each other;
A second feed probe that is disposed at an end of the quad ridge waveguide portion on the double ridge waveguide portion side and feeds power between the opposing third protrusions;
The cutoff frequency in the propagation mode of the radio wave input / output by the second feeding probe is set in the double ridge waveguide section so as to be higher than the frequency of the radio wave. Antenna device. A first probe insertion hole penetrating the first protrusion, and a second probe insertion hole penetrating the third protrusion;
The first power supply probe is inserted into the first probe insertion hole,
The second feed probe antenna device according to claim 1, characterized in that it is inserted through the second probe insertion hole.   The antenna device according to claim 2, wherein a surface including the first protruding ridge facing and a surface including the third protruding ridge facing each other are orthogonal to each other. A first feeding circuit unit provided outside the double ridge waveguide unit and connected to the first feeding probe;
A second feeding circuit unit provided outside the quadridge waveguide unit and connected to the second feeding probe;
The antenna device according to claim 2, further comprising: The antenna device according to claim 4, wherein the first feeding circuit unit and the second feeding circuit unit are configured by coaxial lines. 2. The short-circuited waveguide section, the double ridge waveguide section, and the quad ridge waveguide section are configured by a rectangular waveguide having a rectangular cross section. 6. The antenna device according to any one of items 5. The short waveguide section, the double ridge waveguide section and the quad ridge waveguide section, wherein the preceding claims, characterized in that the shape of the cross section is constituted by a square rectangular waveguide 6. The antenna device according to any one of items 5. The short-circuited waveguide section, the double ridge waveguide section, and the quad ridge waveguide section are configured by circular waveguides having a circular cross section. 6. The antenna device according to any one of items 5. A short-circuited waveguide section in which one end is electrically short-circuited;
A double ridge waveguide portion provided so as to communicate with the other end portion of the short-circuited waveguide portion and having a pair of first protrusions opposed to each other along the longitudinal direction of the inner surface portion;
A pair of second portions provided so as to communicate with one end portion at the other end portion of the double ridge waveguide portion and opposed to each other along the longitudinal direction of the inner surface portion so as to be continuous with the first protrusion. A quadridge waveguide portion having a ridge and having a pair of third ridges disposed opposite to the inner surface portion between the second ridges;
A first dielectric substrate provided between the short-circuited waveguide section and the double-ridge waveguide section;
A first feed line that is provided on the first dielectric substrate and feeds power between the opposing first protrusions;
A second dielectric substrate provided between the double ridge waveguide portion and the quad ridge waveguide portion;
A second feed line provided on the second dielectric substrate and feeding power between the opposing third protrusions;
The cutoff frequency in the propagation mode of radio waves input and output by the second feeder line is set in the double ridge waveguide section so as to be higher than the frequency of the radio waves. Antenna device.   The antenna device according to claim 9, wherein a surface including the first ridge facing and a surface including the third ridge facing each other are orthogonal to each other. A first feed circuit unit provided outside the double ridge waveguide unit and connected to the first feed line;
A second feed circuit portion provided outside the quadridge waveguide portion and connected to the second feed line;
The antenna device according to claim 9, wherein the antenna device is provided. The first feeding circuit section and the second feed circuit includes an antenna device according to claim 11, characterized in that it is constituted by a strip line. The antenna device according to claim 11, wherein the first feeding circuit unit and the second feeding circuit unit are configured by a suspended strip line. 10. The short-circuit waveguide portion, the double ridge waveguide portion, and the quad ridge waveguide portion are configured by a rectangular waveguide having a rectangular cross section. 14. The antenna device according to any one of items 13. The short waveguide section, the double ridge waveguide section and the quad ridge waveguide section, wherein the claim 9, characterized in that the shape of the cross section is constituted by a square rectangular waveguide 14. The antenna device according to any one of items 13. 10. The short-circuit waveguide portion, the double ridge waveguide portion, and the quad ridge waveguide portion are configured by circular waveguides having a circular cross section. 14. The antenna device according to any one of items 13.

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