JPS6220721B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a Faraday rotary wave element type reversible phase shifter having excellent reversible phase characteristics.

FIG. 1 is a perspective view showing the structure of a conventional Faraday spiral waveform reversible phase shifter, and FIG.
b, c are sectional views taken along lines AA, BB, and CC in FIG. 1; A conventional Faraday rotary wave element type reversible phase shifter has a ferrimagnetic material 1 having a cylindrical shape or a square column shape with a square bottom, and has a plated side surface parallel to the radio wave propagation direction, and a magnetizing conductor 2 on the side surface of the ferrimagnetic material 1. The yoke 3 is arranged so that the magnetization M remains, forming a Faraday rotator 4, and four permanent magnet plates 5 are placed at both ends on the side surface of the Ferri magnetic body 1.
a first circularly polarized wave generator 6 in which the north and south poles of the permanent magnet plate 4 of the first circularly polarized wave generator 6 are arranged oppositely, and the north and south poles of the permanent magnet plate 4 of the first circularly polarized wave generator 6 are arranged oppositely It has a structure in which the second circularly polarized wave generator 7 is configured as follows.

Next, the operation will be explained. When a linearly polarized wave enters from the left side in FIG. At this time, when a pulsed current is passed through the magnetizing conducting wire 2, the magnetization M remains in the direction shown in FIG. 2a. Since the rotation direction of the circularly polarized wave has a right-handed screw relationship with respect to the direction of the magnetization M, the ferrimagnetic body 1 exhibits right-handed circularly polarized wave permeability. The right-handed circularly polarized wave, which has undergone a phase change due to this, passes through the second circularly polarized wave generator 7 and is then converted into a linearly polarized wave.

Conversely, when a linearly polarized wave enters from the right side of the phase shifter shown in FIG. If the same magnetization M as above remains,
Since the rotation direction of the circularly polarized wave has a right-handed screw relationship with respect to the direction of the magnetization M, it exhibits the same right-handed circularly polarized wave permeability as described above, and the transmission phase after passing through the first circularly polarized wave generator 6 is: This is the same as in the previous case. Therefore, for the same residual magnetization M, the phase shifter exhibits the same transmission phase even if linearly polarized waves are incident from either the left or right direction of the phase shifter, so it operates as a reversible phase shifter.

When such a phase shifter is used in a phased array antenna or the like, it is required to have high power resistance and the reversibility described above.

However, when an external stress such as twisting is applied to the phase shifter, the phase shifter, which should be originally reversible, may become irreversible due to the magnetostrictive effect of the ferrimagnetic material 1. Examples of ferrimagnetic materials with low magnetostrictive effects include Li (lithium) and Mg-Mn (magnesium-manganese) materials. However, as the peak value of the pulsed high-frequency power increases, there is a phenomenon in which the insertion loss rapidly increases from a relatively low peak value. On the other hand, YIG
Although the peak value of the (yttrium-iron-garnet) system can be greatly increased by adding rare earth ions such as Ho (holomium), it has the drawback that the magnetostrictive effect increases. Therefore, in conventional high-power phase shifters, a YIG-based ferrimagnetic material has to be used while allowing a certain degree of phase irreversibility.

FIGS. 3a and 3b are diagrams for explaining the inverse Wiedemann effect, which is one of the magnetostrictive effects.

When a twisting force P is applied to the ferrimagnetic material 1, and a magnetic field H is applied in the direction of radio wave propagation, the ferrimagnetic material 1
The phenomenon in which not only the magnetization component M _H in the direction of the magnetic field H but also the magnetization component M _R appears in the circumferential direction is called the reverse Wiedemann effect. Furthermore, it is known that when the direction of the magnetic field H is reversed, the magnetization component M _R in the circumferential direction is also reversed.

When the above phenomenon occurs in the Faraday rotation wave element 4 of the phase shifter, the magnetization component M _H in the magnetic field H direction is the magnetization required for the reversible phase shifter, and the magnetization component M _R in the circumferential direction is the irreversible magnetization component M H This is unnecessary magnetization that causes magnetization.
FIGS. 4a and 4b are diagrams showing the Faraday rotary wave element 4 with the magnetization conducting wire 2 and yoke 3 removed in order to explain the relationship between the circumferential magnetization component M _R and irreversibility. A high-frequency rotating magnetic field h exists in the Faraday rotating wave element 4, which is independent of the rotating direction of the circularly polarized wave passing therethrough and whose rotating direction differs depending on the propagation direction D.
Therefore, when a predetermined circumferential magnetization component M _R exists, the ferrimagnetic material 1 exhibits left-handed circularly polarized permeability for circularly polarized waves propagating in the D direction shown in FIG. 4a. . If the phase delay caused by this is θ, then the phase will advance by θ because the ferrimagnetic material 1 exhibits right-handed circularly polarized wave permeability with respect to the circularly polarized wave propagating in the opposite D direction shown in Fig. 4b. Become.

From the above, in the conventional phase shifter, if the phase that should be obtained during normal reversible operation is φ, the phase when the radio wave passes in one direction is φ - θ, and the phase when it passes in the opposite direction is φ - θ. If the phase is φ+θ
Therefore, there was a drawback that the 2θ phase difference appeared as irreversibility.

In order to eliminate such drawbacks, this invention arranges circularly polarized wave generators at both ends of the ferrimagnetic material 1, and furthermore, arranges a 180 degree plate between both circularly polarized wave generators to generate each circularly polarized wave. A yoke 3 that forms a magnetic circuit with the ferrimagnetic material 1 is arranged on the side surface of the ferrimagnetic material 1 between the generator and the 180-degree plate, and a magnetizing conductor 2 is wound around the yoke 3 or the ferrimagnetic material to form two Faraday rotators. The drawings will be described in detail below.

5 and 6 a, b, c, and d are perspective views and their A-A, respectively, of embodiments of the present invention.
BB, CC, and DD cross-sectional views are shown. The phase shifter according to the present invention includes a first circularly polarized wave generator 6, a first circularly polarized wave generator 6, and a first circularly polarized wave generator 6, in which four permanent magnet plates 5 are arranged around the side surface of a plated ferrimagnetic body 1 so that the north pole and the south pole face each other. A second circularly polarized wave generator 7 whose poles are arranged in the same way as the first circularly polarized wave generator 6, and a 180 degree plate 8 whose poles are arranged in the same way or inversely as the first circularly polarized wave generator 6, A first circularly polarized wave generator 6 is placed at one end of the ferrimagnetic body 1, a 180 degree plate 8 is placed at the center, and a second circularly polarized wave generator 7 is placed at the other end at equal intervals along the radio wave propagation direction. The first circularly polarized wave generator 6 and the 180 degree plate 8, 180
A yoke 3 is arranged on the side surface of the ferrimagnetic body 1 so that the magnetization M remains in opposite directions in the ferrimagnetic body 1 between the dial 8 and the second circularly polarized wave generator 7. , a magnetizing conducting wire 2 is wound around a Ferrimagnetic material 1 or a yoke 3 to form a first Faraday rotating wave element 9 and a second Faraday rotating wave element 10.

7a and 7b are diagrams with the magnetizing conductor 2 and yoke 3 removed to explain the operation of the phase shifter according to the present invention. When a twisting force P is applied to the phase shifter, when a pulsed current is passed through the magnetizing conductor 2, the first Faraday rotating wave element 9 and the second Faraday rotating wave element 10 are magnetized in the direction of the magnetic field H. Not only do the components M _H remain in opposite directions, but also the magnetization components M _R in the circumferential direction remain in opposite directions due to the aforementioned reverse Wiedemann effect.

As a result, the linearly polarized wave incident along the propagation direction D shown in FIG. 7a is transmitted to the first circularly polarized wave generator 6.
In the first Faraday rotation wave element 9, it becomes a right-handed circularly polarized wave R, so the magnetization component M _H in the direction of the magnetic field H
The relationship is right-handed, and the ferrimagnetic body 1 exhibits right-handed circularly polarized magnetic permeability. The phase advance from the demagnetized state due to this is defined as φ'. On the other hand, the magnetization component M _R in the circumferential direction and the high-frequency rotating magnetic field h have a left-handed screw relationship, and the ferrimagnetic body 1 exhibits left-handed circularly polarized magnetic permeability. The phase delay caused by this is assumed to be -θ'. Therefore, the right-handed circularly polarized wave R passing through the first Faraday rotation wave element 9
The phase change of is φ'-θ'. Next, this right-handed circularly polarized wave R passes through the 180-degree plate 8, is converted into a left-handed circularly polarized wave L, and passes through the second Faraday rotating wave element 10. At this time, the left-handed circularly polarized wave L and the magnetization component M in the direction of the magnetic field H
_H has a right-handed screw relationship, and like the inside of the first Faraday rotary wave element 9, the Ferri magnetic body 1 exhibits right-handed circularly polarized permeability, and the phase lead is φ'. On the other hand, the magnetization component M _R in the circumferential direction and the high-frequency rotating magnetic field h have a right-handed screw relationship, and the ferrimagnetic body 1 exhibits right-handed circularly polarized magnetic permeability. The phase advance resulting from this becomes θ'. As a result, the left-handed circularly polarized wave L that entered the second Faraday rotating wave element 10 with a phase change of φ' - θ' further undergoes a phase change of φ' + θ', as shown in equation (1). , phase delay due to circumferential magnetization component M _R -
It advances with θ' and θ' cancels each other out.

φ′−θ′+φ′+θ′=2φ′ −(1) Therefore, after passing through the second circularly polarized wave generator 7,
A linearly polarized wave that has undergone a phase change of φ' appears at the output end of the phase shifter.

Conversely, the linearly polarized wave incident along the propagation direction D shown in FIG. ′+θ′, and further the first
The left-handed circularly polarized wave L passing through the Faraday rotary wave element 9 of
undergoes a phase change of φ'-θ'. Therefore, a linearly polarized wave that has undergone a phase change of 2φ' as described above appears at the output end of the phase shifter.

That is, according to this structure, even when using a ferrimagnetic material that is likely to produce a magnetostrictive effect, a reversible phase shifter can be obtained by canceling out the irreversible phase component.

Although the latching method using the magnetization M remaining in the Faraday rotary wave element 1 has been described above, the present invention is not limited to this, and may be used in an analog method that does not use the yoke 3.

As described above, in the Faraday rotary wave element type reversible phase shifter according to the present invention, the plated ferrimagnetic material 1
The first magnet is made up of four permanent magnet plates 5 arranged on the side surface.
and second circularly polarized wave generators 6, 7 and 180 degree plate 8 respectively along the radio wave propagation direction.
A first circularly polarized wave generator 6 at one end, a 180 degree plate 8 at the center, and a second circularly polarized wave generator 7 at the other end are arranged at equal intervals in this order, and the first and second circularly polarized waves are Generators 6, 7 and
By configuring the first and second Faraday rotary wave elements 9 and 10 between the 180-degree plate 8, it is possible to cancel out the irreversible component of the phase due to magnetostriction, and to obtain excellent reversible phase characteristics. I can do it.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of a conventional Faraday spiral waveform reversible phase shifter, Fig. 2a is a sectional view taken along line AA in Fig. Figure c is the first
3A and 3B are explanatory diagrams of the inverse Wiedemann effect, FIG. 4 is an explanatory diagram of the irreversibility of a conventional Faraday rotary waveform reversible phase shifter, and FIG. 5 is an explanatory diagram of the present invention. FIG. 6a is a perspective view of the embodiment of FIG.
-A sectional view, Figure 6b is the BB sectional view of Figure 5,
6c is a sectional view taken along the line CC in FIG. 5, FIG. 6d is a sectional view taken along the line DD in FIG. 5, and FIGS. 7a and 7b are explanatory views of the effects of the present invention. In the figure, 1 is a ferrimagnetic material, 2 is a magnetization conductive wire, and 3 is a ferrimagnetic material.
is a yoke, 4 is a Faraday rotator, 5 is a permanent magnet plate, 6 is a first circularly polarized wave generator, 7 is a second circularly polarized wave generator, 8 is a 180 degree plate, and 9 is the first Faraday rotator. Wave element 10 is a second Faraday rotation wave element. In the drawings, the same or corresponding parts are denoted by the same reference numerals.

Claims (1)

[Claims] 1 The side surfaces of a prismatic ferrimagnetic body having a columnar shape or a square bottom surface are coated with metal, and four permanent magnets are placed around the columnar ferrimagnetic body so that the N pole and the S pole face each other in a predetermined direction. A magnetic circuit is provided on the side surface of the columnar ferrimagnetic material having the same bottom surface as the ferrimagnetic material and coated with metal on the side surface. A first circularly polarized wave is generated by arranging a yoke to form a yoke and winding a magnetizing conductor around the yoke or a ferrimagnetic material. A first Faraday rotator, a 180 degree plate, a second Faraday rotator whose magnetization is always excited in the opposite direction to that of the first Faraday rotator, and a second circularly polarized wave generator are arranged in this order. A Faraday rotary waveform reversible phase shifter, characterized in that it is configured with a Faraday circular waveform.