JP3011111B2 - Broadband antenna feeder - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an antenna feeder, and more particularly to a broadband antenna feeder capable of switching between a circularly polarized wave and a linearly polarized wave in a wide band in a high frequency band such as a microwave band.

[0002]

2. Description of the Related Art Conventionally, microwave antennas used for satellite communications and the like generally operate electromagnetic waves with circularly or linearly polarized waves. In order to realize these circularly polarized waves and linearly polarized waves with one antenna, an antenna feed device using a polarizer (rotary phase shifter) may be used. That is, FIG. 5 is a block diagram showing a configuration of a conventional antenna power supply device using a polarizer.

[0003] In the figure, two π / 2 polarizers 108 and 110 are a rotary joint (R / J) 1.
The rotary joint 111 is connected to the polarizer / demultiplexer 112 via cascade connections 07, 109, and 111.

In this figure, in the case of circular polarization, only one π / 2 polarizer of two π / 2 polarizers acts on an electromagnetic wave, and the other does not act. On the other hand, in the case of linearly polarized light, a π polarizer is formed by operating two π / 2 polarizers.

Next, a specific operation of converting between circularly polarized light and linearly polarized light having the above-described configuration will be described with reference to the drawings.

First, FIG. 6 is a block diagram showing the function of the polarization conversion unit in the case of an antenna operated with circular polarization.
Shown in As shown in the figure, a circularly polarized wave is represented by a configuration in which a polarization splitter 102 and a π / 2 polarizer 101 are combined.

The specific structure of the block diagram of FIG. 6 is as shown in FIG. 7, in which a right-handed polarization port 61, a metal short plate 63, a polarizer / demultiplexer 60, a left-handed polarization port 62, and a metal short plate 64 From the x-axis 45
It is composed of a π / 2 polarizer 65 having a phase delay surface 66 inclined.

Here, the π / 2 polarizer is shown in FIG.
As shown in (a), a phase delay surface 71 (yz plane) having a dielectric constant different from other surfaces is provided in the waveguide 70, and a phase delay surface having a length L is provided. 71 is an electromagnetic wave (TE11
While the (mode) passes, the phase difference between the component (x component) of the electromagnetic wave (TE11 mode) perpendicular to the phase delay surface 71 and the component (y component) of the horizontal electromagnetic wave (TE11 mode) is π / 2. (90 degrees).

Therefore, when an electromagnetic wave passes through a π / 2 polarizer, linearly polarized waves are converted into circularly polarized waves, and circularly polarized waves are converted into linearly polarized waves.

The actual configuration of the phase delay surface 71 is generally such that a plurality of adjustment screws 74 are inserted in the waveguide 73y-z plane direction as shown in FIG.

FIG. 8B, FIG. 8C, FIG.
(E) and (f) respectively show z = 0, L / 4, 2L /
It is a figure which shows the electric field vector of (pi) / 2 polarizer in the position of 4,3L / 4, L. Fig. 8 (b)-
8F, electric field vectors 173, 174, 175, and 176 are obtained for the electric field vector 72 at z = 0 in FIG. 8B according to the length in the z direction, and the linear polarization is converted to the circular polarization. It has been shown.

On the other hand, in the case of an antenna operated with linear polarization, FIG. 10 is a block diagram showing the function of a polarization converter. In this drawing, two rotary joints 10
It is composed of a π polarizer 104 that can be freely rotated by being sandwiched between 3, 105, and a polarizer. Here, like the π / 2 polarizer described above, when two orthogonal electromagnetic waves (TE11 mode) pass through the π polarizer, a component of the electromagnetic wave (TE11 mode) horizontal to the phase delay plane and a component perpendicular to the electromagnetic wave (TE11 mode) The phase difference with the component of the TE11 mode is π (180 degrees).

Therefore, when the electromagnetic wave passes through the π polarizer 75 as shown in FIG.
By changing the angle θ between the phase shifter 8 and the phase delay surface 77, the polarization plane can be freely rotated. Note that π
The polarizer is a π / 2 polarizer 8 as shown in FIG.
0, 90 in cascade to form two phase delay surfaces 83,
The π polarizer can also be formed by disposing the 93 in the same plane and setting the length of the phase delay plane in the z direction to 2L.

For example, as shown in FIG.
The angle of polarization of the electric field 78 input to the π polarizer 75 is θ0. When an electromagnetic wave incident from the phase delay surface 77 at a polarization angle of θ0 passes through the π polarizer 75,
Output (at z = 2L) at a polarization angle of .theta. =. Pi .-. Theta.0.
(See FIG. 11 (j)).

The electric field vectors 179, 180, 181, 182, 183, and 183 shown in FIGS.
Reference numerals 184, 185, and 186 denote states when the electric field vector 78 is input to the π / 2 polarizer.

As described above, the π polarizer is capable of rotating the plane of polarization of a linearly polarized electromagnetic wave around the central axis (z axis) of the polarizer.

Therefore, even if the polarization plane of the input electromagnetic wave does not match the polarization plane of the polarizer / demultiplexer, the π polarizer is rotated to rotate the polarization plane, so that the polarizer can be operated. be able to.

Regarding the configuration of the antenna feeding device using the conventional polarizer described above, for example, see “Satellite Communication Technology”, edited by the Institute of Electronics and Communication Engineers, supervised by Kenichi Miya, 1980 (Showa 55)
It is described on pages 150 to 151 issued on January 10th.

Examples of a phase shifter using a polarizer include, for example, “Microwave Circuit”, Nikkan Kogyo Shimbun, Munenori Ishii et al., Pages 205 to 212, published on February 28, 1969. Has been described.

[0020]

As described above, the frequency characteristics of an antenna feeder used by switching between circularly polarized waves and linearly polarized waves largely depend on the characteristics of the polarizer and the polarization splitter.

That is, the phase shift difference versus frequency characteristic of two orthogonal electromagnetic waves (TE11 mode) in the π / 2 polarizer generally has a characteristic as shown in FIG. The antenna power feeding device has a phase shift characteristic of 90 °
In this case, an axial ratio characteristic exhibiting ideal characteristics is obtained, and is used in a frequency range (fa to fb) giving a phase shift difference (90 ± α °) from 90 ° so as not to exceed a desired value α. Use a polarizer with such characteristics to widen the frequency band,
That is, fa 'to fb' (fa '<fa <fb <fb')
If this is attempted, the phase difference between the two orthogonal electromagnetic waves (TE11mode) exceeds the range (90 ° ± α) in which the desired axial ratio characteristics can be maintained, as shown in FIG.

Accordingly, there is a problem in that the frequency band used by the polarizer has certain restrictions, so that the frequency band used by the power supply device itself is limited.

Further, not only the π / 2 polarizer but also the polarization demultiplexer is subject to band limitation due to the return loss characteristics. That is, as shown in FIG. 14, the return loss characteristics of the polarization splitter used in fa to fb are rapidly deteriorated in other than fa to fb. Therefore, if an attempt is made to widen the frequency band used in the polarization splitter, the return loss characteristics will be degraded outside the band of fa to fb. Was.

As shown above, when the power supply device is widened using a conventional polarizer or polarizer, it is difficult to maintain desired axial ratio characteristics and return loss characteristics of the power supply device. There is a problem that there is. The present invention has been made in view of the above problems, and an object of the present invention is to switch between circularly polarized light and linearly polarized light that achieves good characteristics in characteristics such as phase shift difference and return loss even when the frequency is widened. Another object of the present invention is to provide a simple antenna device.

[0025]

According to the present invention, there is provided a broadband antenna feeder for switching two orthogonal electromagnetic waves propagating through a waveguide into a circularly polarized wave or a linearly polarized wave to feed the antenna. the frequency band of electromagnetic waves N (N is a natural number of 2 or more) is divided, the divided to a pair of two connected in cascade for each band [pi / 2 polarizer N sets cascade of N sets of [pi / 2-polarizer
And the π according to the band of each π / 2 polarizer.
And a phase shift means for adjusting the phase shift by rotating the phase delay plane of the / 2 polarizer, wherein only one set of π / 2 polarizers among the N sets of π / 2 polarizers is circularly polarized.
Or the other set of π / 2 points
The phase delay plane so that no phase difference occurs.
It is characterized by rotating by a predetermined angle .

In the case where the rotation of the predetermined angle is performed in an arbitrary one of the divided bands, only a set of π / 2 polarizers adjusted to the band may be circularly or linearly polarized. (N-1) sets of π / 2 polarizers whose rotational phase shifts are switched so as to form waves and are adjusted to other divided bands, the phase shift difference of each of the two π / 2 polarizers is π / 2. It is characterized in that the rotational phase shift is switched as much as possible.

Further, the π / 2 polarizer is characterized in that the π / 2 polarizer has the phase delay surface which is sandwiched between rotary joints and rotates with respect to a waveguide axis.

Further, the wide-band antenna power supply device includes:
The output of the N sets of π / 2 polarizers is characterized by having a polarization splitter having N ports whose return loss characteristics are adjusted for each of the divided bands.

Further, the invention is characterized in that the waveguide is a round-angle conversion waveguide.

Further, the broadband antenna power supply device of the present invention is a wideband antenna power supply device for switching two orthogonal electromagnetic waves propagating through a waveguide into a circularly polarized wave or a linearly polarized wave and feeding the antenna to the antenna. The band is divided into N (N is a natural number of 2 or more), and the two bands whose phase shift characteristics are adjusted for each of the divided bands are cascaded as one set
And the 2N [pi / 2 polarizer that is, the 2N number of [pi
(2N + 1) rotary joints that respectively sandwich the / 2 polarizer and rotate with respect to the waveguide axis;
A polarizer having N ports whose return loss characteristics are adjusted for each of the divided bands to the outputs of the 2N π / 2 polarizers, wherein the 2N π / 2 polarizers include : Only a set of two π / 2 polarizers is circularly polarized
Alternatively, it is converted to linearly polarized wave, and the other set of 2 (N
-1) The number of π / 2 polarizers is set so that no phase shift occurs.
Preferably, the phase delay plane is rotated by a predetermined angle .

In the case where the rotation of the predetermined angle is performed in any one of the divided bands, only the two π / 2 polarizers adjusted to the band are circularly polarized or linearly polarized. The 2 (N-1) π / 2 polarizers whose rotational phase shifts are switched so as to form waves and are adjusted to other divided bands, the phase shift differences of the two π / 2 polarizers are each π / 2. The rotation phase shift is switched so that

[0032]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing an embodiment of the antenna feeding device of the present invention.

First, the frequency band (f0 to f2; f0 <f2) of the radio signal to be transmitted by the antenna power supply device is
Two bands, a low frequency region (fL) and a high frequency region (fL)
H). Here, fL and fH are f
0 ≦ fL ≦ f1 and f1 ≦ fH ≦ f2.

The π / 2 polarizer 2 adjusted in each of the frequency bands fL and fH so that the circular polarization can be converted to linear polarization or the plane of polarization of linear polarization can be converted to rotation polarization. , 4, 6, 8 are connected in cascade, two sets each for a total of four.

A demultiplexer 1 having two independent ports 11 and 12, a port having good return loss characteristics in the fL band and a port having good return loss characteristics in the fH band.
0 is connected to the aforementioned π / 2 polarizer.

The present invention provides a total of four π / 2 polarizers, π / 2 polarizers 2, 4 adjusted to the frequency band of fL, and π / 2 polarizers 6, 8 adjusted to the frequency band of fH, and Rotary joints 1,3 installed so as to sandwich 2,4,6,8 polarizers
5, 7, and 9, and the demultiplexer 10 usable in the two frequency bands fL and fH are connected to adjust the rotation angle of the phase delay plane with respect to the waveguide axis of the two π / 2 polarizers. This adjusts the phase shift amount of each component of two orthogonal electromagnetic waves (TE11 mode). As a result, it is possible to use a single antenna to switch between circularly polarized waves and linearly polarized waves in the band of fL or circularly polarized waves and linearly polarized waves in the band of fH so as to be able to operate in a wider band than before.

In a wider frequency band than in the prior art, circular polarized waves (right-handed or left-handed) or linearly polarized waves (vertical or horizontal) can be switched for operation.

Next, the operation of the antenna feeding device of the present invention will be described in more detail.

FIG. 2 shows the π / 2 polarizers 2, 4, 6, 8 and the polarization splitter 10 shown in FIG.
FIG. 3 is a diagram separately illustrated in a frequency domain and a polarization plane.

First, in the frequency band of the low frequency region fL shown in FIG.
y polarized wave) will be described.

As shown in FIG. 2B, the phase delay surfaces 16 and 18 in the two π / 2 polarizers 6 and 8 adjusted for the frequency band of fH are shifted by 90 ° from each other. . The phase delay surfaces 16 and 18 may be oriented in any direction as long as they are shifted by 90 °.

At this time, π / F adjusted for the frequency band of fH
When electromagnetic waves of fL and fH pass through the two-polarizer 6,
The electromagnetic wave of the component parallel to the phase shift delay surface 16 in the π / 2 polarizer 6 has a phase of 90 degrees with respect to the electromagnetic wave of the vertical component.
° Delay.

Next, π / F adjusted for the frequency band of fH
When electromagnetic waves fL and fH pass through the two-polarizer 8,
The electromagnetic wave of the component parallel to the phase delay plane 18 in the π / 2 polarizer 18 has a phase of 9% with respect to the electromagnetic wave of the vertical component.
Delay by 0 °.

Since the π / 2 polarizer 6 and the π / 2 polarizer 8 are shifted from each other by 90 ° with respect to the waveguide axis,
The phase delay plane 16 and the phase delay plane 18 are shifted from each other by 90 ° with respect to the waveguide axis in the π / 2 polarizer 16 and the π / 2 polarizer 18.

Therefore, electromagnetic waves of components parallel to each of the two phase delay surfaces 16 and 18 shifted by 90 ° and orthogonal to each other with respect to the waveguide axis are applied to both of the two π / 2 polarizers 6 and 8. , The phase shift difference disappears.

That is, the phase delay plane 16 and the phase delay plane 18
Passes through both of the two π / 2 polarizers 6 and 8 which are shifted from each other by 90 ° with respect to the tube axis, the polarization is not affected in any of the frequency bands fL and fH.

Next, the electromagnetic waves of fL and fH pass through the two π / 2 polarizers 2 and 4 adjusted for the frequency band of fL, and the electromagnetic waves of the band of fL pass through the π / 2 polarizer 2.
When the phase delay plane 12 is set at + 45 ° with respect to the x axis, the phase is converted into left-handed circularly polarized wave (LHCP), and when taken at −45 °, right-handed circularly polarized wave (RHCP) is obtained.

As described above, the direction of the electric field in the polarization splitter 10 is the y-axis direction. At this time, the phase delay surfaces 16 and 18 of the polarizers 6 and 8 in the band of fH are respectively set to 90 °.
So that no phase shift occurs in the x-axis and y-axis after the electromagnetic waves pass through the polarizers 6 and 8. Further, one of the phase delay surfaces 12 and 14 of the polarizers 2 and 4 in the fL band is made parallel to the x-axis, and the other is tilted + 45 ° from the x-axis, and left-handed circularly polarized light is tilted at −45 °. It is converted to circularly polarized electromagnetic waves.

Next, the operation of circularly polarized waves in the high frequency region of FIG. 2C will be described.

As shown in FIG. 2C, the direction of the electric field in the polarization splitter 10 is defined as the x-axis direction. At this time, the phase delay surfaces 12 and 14 of the polarizers 2 and 4 in the band of fL are set to be parallel to the x-axis and the y-axis (or the y-axis and the x-axis), respectively, and after the electromagnetic waves pass through the polarizers 2 and 4, x
A phase shift difference is not generated between the axis and the y axis. Also, f
Phase delay surfaces 16, 18 of polarizers 6, 8 in the H band
Is parallel to the y-axis and the other is +
An electromagnetic wave of right-handed circularly polarized wave (RHCP) can be operated when tilted by 45 °, and a left-handed circularly polarized wave (LHCP) can be operated when tilted by −45 °.

Next, a linear polarized wave in the low frequency region shown in FIG.
The operation of e) will be described.

As shown in FIG. 2D, the direction of the electric field in the polarization splitter is defined as the y-axis direction. At this time, the phase delay surfaces 16 and 18 of the polarizers 6 and 8 in the band of fH are respectively set to x
The polarizers are set so as to be parallel to the axis and the y-axis (or the y-axis and the x-axis) so that no phase shift occurs between the x-axis and the y-axis after the electromagnetic waves pass through both the polarizers 6 and 8. Also,
The phase delay surfaces 12, 1 of the polarizers 2, 4 in the band of fL
4 from the x-axis θ = −θ2, −θ4 ° (θ2 = θ4
> 0) When tilted, electromagnetic waves having a component of θ = π / 2 + 2 (−θ2) can be operated.

Finally, the operation of linearly polarized waves in the high frequency region shown in FIG.

As shown in FIG. 2E, the direction of the electric field in the polarization splitter is defined as the x-axis direction. At this time, the phase delay surfaces 12 and 14 of the polarizers 2 and 4 in the band of fL are respectively set to x
It is made parallel to the axis and the y-axis (or the y-axis and the x-axis) so that no phase shift occurs between the x-axis and the y-axis after the electromagnetic waves pass through both the polarizers 2 and 4. Also,
The phase delay surfaces 16, 1 of the polarizers 6, 8 in the band of fH
8 from the x-axis θ = θ6, θ8 (θ6 = θ8> 0)
When tilted, electromagnetic waves having a component of θ = π + 2 (θ6) can be operated.

[0055]

Next, an example showing a specific configuration of an embodiment of the present invention will be described with reference to the drawings.

FIG. 3 shows a first embodiment in which a round-angle conversion waveguide is used for the polarization splitter of the antenna feeding device of the present invention.

In this figure, five rotary joints 201, 204, 207,
210 and 213 are provided, and four π / 2 polarizers 202, 205, 208 and 211 are attached between them.

Here, the π / 2 polarizers 202 and 20
5 is adjusted for fH and the π / 2 polarizer 20
8, 211 are assumed to be adjusted for fL.

In this case, the phase delay surfaces 212 and 209 of the π / 2 polarizers 211 and 208 have a 90 ° phase shift relationship, and the π / 2 polarizers 205 and 202 have a 45 ° phase shift relationship. have.

Accordingly, the configuration of this figure corresponds to fH of FIG.
The configuration corresponds to a circular polarization configuration in a band.

For the frequency band, all π / 2
The polarizer has a frequency bandwidth of about 0.6 GHz, fH = 3.6 to 4.2 (GHx), and fL = 3.0 to 0.0.
By setting it to 3.6 (GHz), 3.0 in all bands
A power supply device having a wide band of about 1.2 GHz of about 4.2 GHz can be obtained.

FIG. 4 shows a second embodiment of the antenna feeder of the present invention using a polarization splitter.

That is, the polarization splitter 314 and four π /
2-polarizers 302, 305, 308, 311 and 5
Rotary joints 301, 304, 307, 3
10,313.

The demultiplexer 314 includes a right-handed polarization port 315, a metal short plate 317, and a left-handed polarization port 316.
And a metal short plate 318.

In this figure, for example, it is assumed that the π / 2 polarizers 311 and 308 are adjusted for fH and the π / 2 polarizers 305 and 302 are adjusted for fL.

In this case, the configuration of this figure has a circularly polarized configuration in the fH band of FIG. 2C as described with reference to FIG.

In the above description, a method has been described in which the frequency band is divided into a high frequency band and a low frequency band for widening the band, but the present invention is not limited to two.

That is, a certain broadband frequency is divided into two or more N bands, and two π / 2 polarizers are adjusted as one set for each band, and each set is cascaded.

Then, N sets of π / 2 polarizers are provided for each of the divided bands, two sets of π / 2 polarizers are provided, and the phase shift characteristics are adjusted according to each band, and the N sets of π / 2 polarizers are used. By rotating the phase delay plane by a predetermined angle, the phase shift of the electromagnetic wave is adjusted to switch the divided band and the circularly polarized wave and the linearly polarized wave. When the rotation at the predetermined angle is operated in any one of the divided bands, only a set of π / 2 polarizers adjusted to the band becomes circularly polarized or linearly polarized. The rotational phase shift was switched so that the frequency was adjusted to another divided band (N-
1) The set of π / 2 polarizers switches the rotational phase shift so that the phase shift difference between two π / 2 polarizers becomes π / 2 from each other.

As a result, it is possible to obtain an effect that a more flexible antenna feed device can be configured than in the case where the antenna is divided into two, and that a broadband antenna feed device can be configured.

[0071]

As described above, the antenna feeder of the present invention having the above-described configuration has an effect that a circularly polarized or linearly polarized signal can be obtained in a wider frequency band than the conventional one. are doing.

Further, there is an effect that the present invention can be applied to radiation of a circularly polarized wave or a linearly polarized wave in a wider frequency band than in the related art.

[Brief description of the drawings]

FIG. 1 is a block diagram of a power supply device according to an embodiment of the present invention.

FIG. 2A is a diagram illustrating connection between a π / 2 polarizer and a polarizer. (B) is a diagram showing a phase shift relationship when a circularly polarized wave is configured in the fL band. (C) is a diagram showing a phase shift relationship in a circularly polarized wave configuration in the fH band. (D) is f
FIG. 9 is a diagram illustrating a phase shift relationship when a linear polarization is configured in the L band. (E) is a diagram showing a phase shift relationship when a linear polarization is configured in the fH band.

FIG. 3 is an external view of a first embodiment using a round angle conversion waveguide as a polarizer.

FIG. 4 is an external view of a second embodiment using a polarizer.

FIG. 5 is a block diagram of a conventional antenna power supply device.

FIG. 6 is a block diagram of a circular polarization power supply device.

FIG. 7 is an external view of a circularly polarized power feeding device.

FIG. 8 is a diagram illustrating a π / 2 polarizer.

FIG. 9 is a diagram illustrating a configuration example of a phase shift delay surface.

FIG. 10 is a block diagram of a linearly polarized power feeding device.

FIG. 11 is a diagram illustrating a π polarizer.

FIG. 12 is a configuration diagram of π / 2 polarizers connected in cascade.

FIG. 13 shows a phase shift characteristic of a conventional π / 2 polarizer.

FIG. 14 shows a return loss characteristic of a conventional polarization splitter.

[Explanation of symbols]

1, 3, 5, 7, 9 Rotary joint 2, π / 2 polarizer for fL 6,8 π / 2 polarizer for fH 10 Polarizer 12, 14, 14 π / 2 polarizer for fH Phase delay plane 16, 18 fL Π / 2 polarizer phase delay surface 60 Polarizer / demultiplexer 61 Right-handed polarization port 62 Left-handed polarization port 63 Right-handed polarization port metal short plate 64 Left-handed polarization port metal short plate 65 π / 2 polarizer 66 Phase delay surface Reference Signs List 70 waveguide 71 phase delay surface 72 input electric field vector 73 waveguide 74 screw for phase adjustment 75 π polarizer 76 waveguide 77 phase delay surface 78 input electric field vector 80 π / 2 polarizer 81 waveguide 82 phase delay surface 90 π / 2 polarizer 91 Waveguide 92 Phase delay plane 173, 174, 175, 176 Electric field vector 179, 180, 181 , 182,183,184,1
85,186 Electric field vector 201,204,207,210,213 Rotary joint 202,205,208,211 π / 2 polarizer 203,206,209,212 Phase delay plane 214 Round angle conversion waveguide

──────────────────────────────────────────────────続 き Continued on the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) H01P 1/17 H01P 1/10 H01P 1/161 H01P 1/165 H01P 1/18 H01P 1/175 JICST file ( JOIS) WPI / L (QUESTEL)

Claims (7)

(57) [Claims] 1. A broadband antenna feeder for switching two orthogonal electromagnetic waves propagating in a waveguide into circularly polarized waves or linearly polarized waves to feed an antenna, wherein the frequency band of the electromagnetic waves is set to N (N is 2 or more). (Numerical number) N sets of π / 2 cascade-connected N sets of π / 2 polarizers each of which is divided and cascade-connected for each of the divided bands.
/ 2 polarizer and the phase delay plane of the π / 2 polarizer are rotated in accordance with the bandwidth of each of the π / 2 polarizers.
And a phase shift means for adjusting a phase shift by performing a phase shift operation by using a set of π / 2 polarizers in the N sets of π / 2 polarizers.
Only the laser is converted to circular or linear polarization,
The other set of π / 2 polarizers should not have any phase shift
A wide-band antenna feeding device, wherein the phase delay plane is rotated by a predetermined angle . 2. The method according to claim 1, wherein the rotation of the predetermined angle is such that, when operating at any one of the divided bands, only a set of π / 2 polarizers adjusted to the band is circularly or linearly polarized. (N-1) sets of π / 2 polarizers whose rotational phase shifts are switched so as to form waves and are adjusted to other divided bands, the phase shift differences of the two π / 2 polarizers are each π.
2. The wide-band antenna power feeding device according to claim 1, wherein the rotation phase shift is switched so as to be / 2. 3. The wideband antenna according to claim 1, wherein each of the π / 2 polarizers has the phase delay surface that is sandwiched between rotary joints and rotates with respect to a waveguide axis. Power supply. 4. The broadband antenna feeding device according to claim 1, wherein
2. The broadband antenna feeder according to claim 1, further comprising: a polarizer / demultiplexer having N ports whose return loss characteristics are adjusted for each of the divided bands at the outputs of the set of π / 2 polarizers. 5. The wide-band antenna feeding device according to claim 1, wherein the waveguide is a round-angle conversion waveguide. 6. A wide-band antenna feeding device for switching two orthogonal electromagnetic waves propagating through a waveguide into circularly polarized waves or linearly polarized waves and feeding the antennas, wherein a frequency band of the electromagnetic waves is set to N (N is 2 or more). (Numerical number) 2 divided and the phase shift characteristics are adjusted for each of the divided bands.
2N π / 2 polarizers cascade-connected as a set , (2N + 1) rotary joints respectively sandwiching the 2N π / 2 polarizers and rotating with respect to the waveguide axis, A polarizer having N ports whose return loss characteristics are adjusted for each of the divided bands to the outputs of the 2N π / 2 polarizers, wherein the 2N π / 2 polarizers include : A set of two π
Only the / 2 polarizer is converted to circular or linear polarization.
And the other set of 2 (N-1) π / 2 polarizers
The phase delay plane so that no phase difference occurs.
A broadband antenna feeding device characterized by rotating by an angle . 7. The method according to claim 1, wherein the rotation of the predetermined angle is such that, when operating at any one of the divided bands, only two π / 2 polarizers adjusted to the band are circularly polarized or linearly polarized. The 2 (N-1) π / 2 polarizers whose rotational phase shifts are switched so as to form waves and are adjusted to other divided bands, the phase shift difference of each of the two π / 2 polarizers is π.
7. The wide-band antenna feeding device according to claim 6, wherein the rotation phase shift is switched so as to be / 2.