JPH07307609A - Array antenna, receiver provided with the array antenna and method for deciding directional characteristic in the array antenna - Google Patents

Abstract

PURPOSE:To reduce the required loads of a receiver for the identification of desired signals by making interference radio waves from a communication satellite present at an adjacent satellite position small or making radio wave interference given to the communication satellite present at the adjacent satellite position small and to make an antenna area small by raising antenna efficiency. CONSTITUTION:Plural antenna elements 12 are arrayed in a grid shape. Power is supplied from the receiver 10 to the respective plural antenna elements 12 so as to be equal amplitude and the same phase and a main beam is turned to the communication satellite defined as a target. The number of the antenna elements 12 and a gap (d) between the respective antenna elements 12 are decided so as to let directional characteristics be a null point for the direction of the communication satellite other than the communication satellite defined as the target and the respective antenna elements are arranged corresponding to the decided number of the antenna elements 12 and gap (d) between the respective antenna elements 12.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an array antenna capable of reducing the received power of radio waves from a specific direction and a receiver or transmitter / receiver equipped with the array antenna.

[0002]

2. Description of the Related Art Conventionally, an antenna used in a receiving device or a transmitting / receiving device for communicating with a communication satellite has a parabolic type antenna such as a parabolic type antenna or a Cassegrain type antenna, and a plurality of antenna elements. And an array antenna that changes the feed amplitude for each antenna element.

FIG. 2 shows an external view of a Cassegrain antenna using a parabolic surface for the main reflecting mirror, and FIG. 3 (a) and FIG.
FIG. 3B shows a configuration diagram of an array antenna that changes the feeding amplitude.

In FIG. 2, a Cassegrain antenna 200 is shown.
Includes a main reflecting mirror 19, a feeding horn 22 that emits or receives a radio wave, a sub-reflecting mirror 20, and a supporting member 21 for fixing the sub-reflecting mirror. In FIG.
A parabolic surface is used for the main reflecting mirror 19 and a hyperboloid is used for the sub-reflecting mirror 20.

The Cassegrain antenna 200 shown in FIG.
When receiving radio waves from a communication satellite, the main reflector 21
Since a part of the radio wave reflected by and collected on the sub-reflecting mirror 23 is blocked by the supporting member 24 for supporting the sub-reflecting mirror 23, the side lobe peak value becomes large and the side lobe characteristic deteriorates. Due to this side lobe characteristic, radio waves interfere with a communication satellite located at an adjacent position, or the earth station itself having this antenna receives radio wave interference from a communication satellite located at an adjacent position. In order to avoid this radio wave interference, the antenna shown in FIG.
The aperture distribution of the main reflecting mirror 21 is optimized in consideration of the blocking effect of the sub reflecting mirror 23 and the supporting member 24 supporting the sub reflecting mirror 23 so that the side lobe peak value is reduced. And the distribution of the aperture surface is non-uniform. Therefore, in order to improve this side lobe characteristic, the influence of the sub-reflecting mirror 23 and the supporting member 24 supporting the sub-reflecting mirror 23 is taken into consideration from the beginning, and the aperture surface distribution of amplitude and phase is optimized from a uniform distribution. It has a non-uniform distribution.

3A and 3B, 31 is a dielectric substrate, 32 is an antenna element such as a patch antenna, 33 is a feeding line for feeding the antenna element, and 34 is It is an unequal distributor and distributes power at a predetermined ratio. Reference numeral 35 denotes an equal distributor, which distributes electric power to each antenna element group. Reference numeral 300 denotes a transceiver, which feeds power to the antenna element and receives a signal received by the antenna element. In the array antenna shown in FIG. 3 (a) or FIG. 3 (b), if the feeding amplitude and feeding phase for all the elements are made uniform,
Similar to the parabolic antenna, the side lobe characteristics are deteriorated, and the radio wave interference received from the communication satellite at the adjacent position and the radio wave interference given to the satellite at the adjacent position become large. Therefore, in order to reduce the radio wave interference received from the communication satellites at the adjacent positions and the radio wave interference given to the communication satellites at the adjacent positions, as shown in FIG. By combining the distributor 34, the feeding amplitude for the antenna element is gradually reduced from the central antenna element toward the outer antenna element. According to this method
The side lobe characteristic of the array antenna is improved, and the radio wave interference received from the adjacent satellites or the radio wave interference given to the adjacent satellites can be reduced.

FIG. 6 is a conceptual diagram showing the directional characteristics of the antenna when power is fed in the configuration as shown in FIGS. 2 and 3 (a). In FIG. 6, reference numeral 61 is a communication satellite for which a transceiver equipped with an antenna attempts to communicate, and 62 is a non-purpose communication satellite for which communication is not performed, which is a communication satellite adjacent to the communication satellite 61. is there. 6
Reference numeral 3 denotes an antenna aperture surface, and 64 denotes a directional characteristic showing the intensity of a radio wave that can be radiated or received by the antenna. When the conventional technique is used, in order to reduce the intensity of the radio wave emitted in the direction of the communication satellite 62 at the adjacent position or the intensity of the radio wave received from the adjacent satellite 62, as shown in FIG.
Power is supplied so as to reduce the overall side lobe of the directional characteristics.

[0008]

As described above, the antenna shown in FIG. 2 has the feeding horn 22 and the sub-reflecting mirror 23 for feeding the beam to the main reflecting mirror 21. Due to the structure placed on the front surface, there is a problem that a part of the beam from the main reflecting mirror 21 is blocked. Therefore, the aperture distribution of the main reflecting mirror 21 is optimized in consideration of the blocking effect of the sub-reflecting mirror 23 and the supporting member 24 supporting the sub-reflecting mirror 23 so that the side lobe peak value is reduced. The distribution of the aperture surfaces is non-uniform. If you do this,
Although it is possible to reduce the radio wave interference given to the communication satellites in the adjacent positions and the radio wave interference received by the earth station itself from the communication satellites, by making the aperture distribution of the main reflecting mirror 21 non-uniform. However, the antenna efficiency is reduced, and the size of the main reflecting mirror 21 for obtaining the required gain becomes larger than that in the case of uniform distribution.

Also in the case of the array antenna shown in FIG. 3, similarly, radio waves interfere with a communication satellite at an adjacent position, and the earth station itself equipped with this array antenna is at an adjacent position. It may be interfered with by the communication satellite. Therefore, in order to prevent radio wave interference from the communication satellites located in the adjacent positions and to prevent radio wave interference from the communication satellites located in the adjacent positions, the side lobe characteristics are improved with respect to each antenna element. Power supply amplitude,
Change the feeding phase. In general, the amplitude distribution is gradually reduced from the center antenna element toward the outer antenna element, and the feed amplitude is gradually reduced to improve the overall characteristics of the side lobes, thereby improving the adjacent position. To reduce the radio wave interference to the communication satellite in, or to reduce the radio wave interference that the earth station itself receives from the communication satellite in the adjacent position. However, this method has a problem in that the antenna efficiency is reduced and the size of the antenna that can obtain the required gain is increased as compared with the case where the amplitude distribution is made uniform.

In order to solve the above problems, it is an object of the present invention to provide an array antenna that is not affected by adjacent communication satellites. Another object of the present invention is to provide an array antenna which has high antenna efficiency and can be downsized.

[0011]

In order to solve the above problems, in an array antenna having a plurality of antenna elements and a feed line for feeding each of the plurality of antenna elements, the feed line is Power is supplied to each of the plurality of antenna elements with the same power supply amplitude and power supply phase, and the number of the plurality of antenna elements and the interval between the antenna elements are defined as the communication other than the intended communication partner. The antenna elements are determined so as not to receive radio waves from the other party, and the plurality of antenna elements are arranged according to the determined number of antenna elements and the spacing between the antenna elements.

Further, in an array antenna in which a plurality of antenna elements are arranged in a grid pattern, a feed circuit for feeding the plurality of antenna elements with the same feed amplitude and feed phase is provided, and at least the grid element is provided. The number of antenna elements on one side and the spacing between the antenna elements are determined according to the directional characteristics such that radio waves from a plurality of predetermined directions are not received, and the determined number of antenna elements and the spacing between the antenna elements. According to the above, the plurality of antenna elements may be arranged.

Further, in a receiving device having a plurality of antenna elements, a feeding line for feeding power to each of the plurality of antenna elements, and a receiving section for receiving a signal received by the antenna element, the receiving section is provided. , The plurality of antenna elements are fed with the same feed amplitude and feed phase, and the number of the plurality of antenna elements and the interval between the antenna elements are different from each other than the intended communication partner. The plurality of antenna elements are arranged so as not to receive radio waves from a communication partner, and the plurality of antenna elements are arranged according to the determined number of antenna elements and the distance between the antenna elements.

As a method of determining the directivity characteristics in an array antenna in which a plurality of antenna elements are arranged, the plurality of antenna elements are fed with the same feed amplitude and feed phase, and the target communication satellite is fed. The number of the plurality of antenna elements and the number of the antenna elements so that the main lobe of the directional characteristic is directed and the directional characteristic becomes a null point with respect to a direction in which a communication satellite other than the target communication satellite exists. The distance between the antenna elements is determined, and the plurality of antenna elements are arranged according to the determined number of antenna elements and the distance between the antenna elements.

[0015]

The present invention is constructed as described above, and its operation will be described below.

Power is supplied with the same amplitude and phase of power supply to each antenna element, and the main lobe of the directional characteristic is directed to the intended communication partner. The number of the plurality of antenna elements and the interval between the antenna elements are determined so that radio waves from other communication partners other than the intended communication partner are not received. The plurality of antenna elements are arranged according to the interval. At this time, the effect of reducing the radio wave interference given to the communication satellites at the adjacent positions and the radio wave interference received from the communication satellites at the adjacent positions will be shown below.

The directional characteristic F of the array antenna is an array factor f representing a term including effects of the directional characteristic g of the antenna element, the spatial arrangement of each antenna element, the feed amplitude, and the feed phase.
Is expressed by the following equation 1.

[0018]

## EQU1 ## F (θ, φ) = g (θ, φ) · | f (θ, φ) | (1) Here, the antenna plane is arranged in the same manner as the coordinate system shown in FIG. Let θ be the zenith angle indicating the inclination from the vertical axis, and φ be the azimuth angle that is on the antenna surface and indicates the angle from the x-axis on the antenna surface.

First, for the sake of simplicity, consider an array factor f of a linear array antenna only when a plurality of antenna elements are arranged in a straight line along the x-axis at equal intervals and the azimuth angle φ is zero. In this case, it is assumed that the intended communication satellite is located on the line connecting the azimuth angles of 0 degree and 180 degrees.
The number of antenna elements is N, and the antenna element spacing is d.
When power is fed to each antenna element at the same amplitude and the same phase, the array factor f is expressed by the following equation 2. In this case, since the feeding phase for each antenna element is the same for all the antenna elements, the peak of the directional characteristic is in the vertical direction with respect to the plane on which the antenna is arranged. That is, since the peak of the directional characteristic is oriented in the direction of θ = 0 and the phase is the same for all the antenna elements, the antenna efficiency can be increased and the antenna aperture area can be reduced.

[0020]

[Equation 2]

In Equation 2, k represents the free space wave number of the radio wave, and j represents the imaginary number. Since Equation 2 is the sum of geometric progressions, it can be rewritten as Equation 3 below.

[0022]

[Equation 3]

Therefore, if the above Equation 3 becomes _{0 in} the direction of a certain specific direction θ ₀ , F (θ ₀ ) representing the directivity characteristic in the θ ₀ direction becomes 0 (this is called a null point) from Equation 1. , Θ ₀ direction does not emit radio waves or does not receive radio waves from θ ₀ direction. Since the numerator on the right-hand side of Expression 3 needs to be 0 in order for Expression 3 to become 0, the following Expression 4 may be satisfied.

[0024]

[Equation 4]

In Expression 4, m represents an integer other than 0. Number 4
According to, no radio wave is emitted in the θ ₀ direction, or
In order not to receive the radio wave from the θ ₀ direction, the number N of antenna elements and the distance d between antenna elements are set so as to satisfy the relationship expressed by the following equation 5 between the number N of antenna elements and the distance d between antenna elements. You know that you should decide.

[0026]

[Equation 5]

[0027] Thus, in relation represented by about a few 5, be determined a number of antenna elements N and the antenna spacing d, does not emit radio wave to theta ₀ direction or a reception intensity of a radio wave from theta ₀ direction Can be made smaller.

By the above method, the number of antenna elements and
FIG. 7 shows a conceptual diagram of directional characteristics when the antenna element spacing is determined. In FIG. 7, reference numeral 71 is a communication satellite with which a transceiver equipped with an antenna attempts to communicate, and 72 is a non-target communication satellite that does not perform communication, and is a communication satellite adjacent to the communication satellite 71. 73 is an antenna opening surface,
Reference numeral 74 indicates a directional characteristic indicating the intensity of the radio wave that can be emitted from the antenna or how much the received radio wave can be collected. As can be seen from FIG. 7, in the present invention, in order to reduce the intensity of the radio wave emitted in the direction of the communication satellite 72 at the adjacent position or the intensity of the radio wave received from the adjacent satellite 72,
The valley where the intensity of the radio wave shown in the directional characteristic becomes small is directed toward the communication satellite at the adjacent position. That is, by setting the direction of θ _{0 to} the direction of the adjacent satellite 72 and determining the number of antenna elements and the spacing between the antenna elements, the directional characteristic in the direction of θ ₀ can be made the null point.

Further, the larger the number of antenna elements and the larger the size of the plane on which the antenna is arranged, the larger the peak size of the directivity characteristic can be made. For this reason, the number of antenna elements and the interval may be determined so as to have a peak of directional characteristics that enables communication with a communication satellite with which communication is desired.

Thus, the antenna efficiency can be improved by making the feeding phase and the feeding amplitude for the antenna element the same, and the size of the entire side lobe can be increased with respect to the communication satellites at the adjacent positions as in the prior art. As compared with the size of the antenna in the case where the feeding amplitude and feeding phase are made non-uniform so as to reduce the size, the unequal distributor is not necessary and the size can be reduced.

[0031]

Embodiments Embodiments will be described below with reference to the drawings.

FIG. 1 is a conceptual diagram of an array antenna and a transceiver according to an embodiment of the present invention. In this embodiment, an antenna element is arranged on a dielectric substrate and a feeding circuit is arranged on another dielectric substrate. In FIG. 1, reference numeral 10 denotes a receiver, which receives a signal received by an antenna element. The receiver 10 may be a transceiver that further includes a transmitter. Reference numeral 11 is a dielectric substrate, and 12 is an antenna element, for example, a square patch antenna element. Reference numeral 13 denotes a power feeding circuit, which is configured by a power feeding line such as a strip line and is connected to the receiver 10. 11
Reference numeral 1 is a feeding point for feeding the antenna element from the feeding circuit, and 112 is a pin or a through hole for feeding the antenna element from the feeding circuit. The board on which the antenna element is arranged and the board on which the power feeding circuit is arranged are arranged in parallel with each other through a predetermined space. Further, the size of the antenna element in this case is independently determined regardless of the number of antenna elements and the interval between the antenna elements. Specifically, the dielectric constant of the medium around the antenna element and the resonance of the radio wave used. It is determined from the conditions. For example, when a rectangular patch antenna element is used, the length of the antenna element with respect to the excitation direction of the antenna element is about 0.5 normalized by the wavelength of radio waves when the medium around the antenna element is a vacuum. become.

In FIG. 1, the number of antenna elements and the distance between the antenna elements are determined by the equation 5. For example, in FIG.
As shown in, when there are eight antenna elements in the horizontal direction, the horizontal direction, that is, the azimuth angle φ = 0 and the zenith angle θ ₀ is 1.
3. Receiver 10 for radio wave interference from adjacent satellites from the direction of 2 degrees
The zenith angle θ ₀ is 1
3. In order to prevent radio wave interference with adjacent satellites in the direction of 2 degrees), N is set to 8 and θ _{0 is set} to 1 from the equation (5).
3.2 degrees, where m is 1, d / λ is 0.547, or m is 2 and d / λ is 1.095. Here, λ represents the free space wavelength of the radio wave. Here, from Equation 5, the antenna element spacing d / λ is strictly 0.54.
However, it may be slightly deviated due to the mutual coupling between the antenna elements.

Next, the number of antenna elements in the lateral direction, that is, in the azimuth angle φ = 0 direction is larger than that of the eight elements shown in FIG.
When there are elements, they are arranged at the following intervals. In order to prevent the receiver 10 from receiving the radio wave interference of the adjacent satellites from the three directions of the zenith angle θ ₀ of 4.4 degrees, 8.8 degrees and 13.2 degrees, in the formula 5, N is set to 32. When θ ₀ is 4.4 degrees, m is 2. When m is 8.8 degrees, m is 4
In the case of 13.2 degrees, m may be set to 6. As a result, each d / λ is 0.81 when it is 4.4 degrees.
It is 0.817 in the case of 5 and 8.8 degrees and 0.821 in the case of 13.2 degrees. Therefore, 32 antenna elements are arranged in the lateral direction, and θ ₀ is 4.4 degrees, 8.8 degrees, and 13.2 degrees in a direction in which the 32 antenna elements are arranged side by side from the adjacent satellites in three directions. In order to reduce the radio wave interference received by 10, the antenna element spacing d / λ may be arbitrarily selected between 0.815 and 0.821.

Up to this point, the case where 32 elements are arranged in the horizontal direction has been shown, but the same can be said for the vertical direction. Even when 16 elements are arranged in the vertical direction, θ _{0 in} a direction in which 16 antenna elements are arranged, that is, in a direction of φ = 90 degrees.
In order to reduce the radio wave interference that the receiver 10 receives from the adjacent satellites in the three directions of 4.4 degrees, 8.8 degrees, and 13.2 degrees, N is set to 16 in Equation 5. When θ ₀ is 4.4 degrees, m
Is 1, the d / λ is 0.815, and when θ ₀ is 8.8 degrees, when m is 2, the d / λ is 0.817 and θ ₀ is 1.
In the case of 3.2 degrees, when m is 3, d / λ is 0.821. Therefore, even when 16 antenna elements are arranged in the direction of φ = 90 degrees, in order to reduce the radio wave interference from the adjacent satellites in the three directions received by the receiver 10, the azimuth angle φ = 0.
Similarly to the case where 32 antenna elements are arranged in the direction of, the vertical antenna element spacing d / λ may be arbitrarily selected from 0.815 to 0.821.

To summarize the above-mentioned method of determining the antenna element spacing, when a total of 512 × 32 antenna elements, that is, 512 elements, are arrayed in a lattice, the element spacing in the direction in which the 32 antenna elements are arrayed. With d / λ between 0.815 and 0.821, the element spacing d / λ in the direction in which the 16 antenna elements are arranged is from 0.817 to 0.8.
It may be arbitrarily selected from among 21. In this case, 16 elements may be arranged in the vertical direction and 32 elements may be arranged in the horizontal direction at the same element interval. That is, the grid-like vertical and horizontal intervals are made equal to the obtained intervals between the antenna elements. In this case, since the element spacing is the same in both the vertical direction and the horizontal direction, it is possible to use whichever is used in the x-axis direction. The elements may be arranged at different arrangement intervals between the above-mentioned element intervals in the vertical direction and the horizontal direction. In this example, m in Equation 5 is determined in order to arrange the array element spacing d / λ in the vertical and horizontal directions of 0.82 as much as possible, but the value of m is naturally an integer other than 0, and , Both lateral directions can be arbitrarily determined. For example, if N is 32 in the horizontal direction, m is 1 when θ ₀ is 4.4 degrees, m is 2 when 8.8 degrees, and m is 3 when 13.2 degrees. Good. As a result, d / λ is 0.407 in the case of 4.4 degrees, 0.409 in the case of 8.8 degrees, and 0.411 in the case of 13.2 degrees, respectively. In this case, the vertical element arrangement interval d / λ is about 0.8, and the horizontal element arrangement interval d / λ.
It is also possible to set λ to around 0.41. Even in this case, it is possible to set the directional characteristic to the null point in the adjacent satellite communication direction.

Next, the directional characteristics of the number of antenna elements and the spacing between the antenna elements described above are shown in FIGS.
Will be described with reference to.

FIG. 8, FIG. 9 and FIG. 10 are layout diagrams of the antenna. In FIGS. 8, 9 and 10, the vertical axis and the horizontal axis are values normalized by frequency, and the spacing of the array is shown by d / λ, and the squares show the antenna elements. FIG. 8 shows a state in which eight elements are arranged in a straight line in the x-axis direction, and FIG.
FIG. 10 shows a state where 16 elements are arranged in a straight line in the axial direction.
Shows the antenna arrangement when 32 elements are arranged in the x-axis direction and 16 elements are arranged in the y-axis in a grid pattern. In this case, the size of the antenna element is standardized by the wavelength of the radio wave to make a square with one side of about 0.5, and the antenna element spacing is
The value is between 0.815λ and 0.821λ.

Further, the far-field directional characteristics of the radio waves radiated from the antenna element array shown in FIG. 8 are shown in FIGS. 11 and 12. In FIG. 11, the intensity of the radio wave radiated from the array antenna is indicated by the shade of the shadow, the azimuth angle φ (0 to 360 degrees) is shown in the circular circumferential direction, and φ is a line connecting 0 degrees and 180 degrees. Shows the x-axis in FIG. 8, and the line connecting φ with 90 degrees and 270 degrees shows the y-axis in FIG. Also, the circles that are shown as concentric circles from the center of the circle indicate the inclination from the vertical axis of the antenna surface, that is, the zenith angle θ. The zenith angle of the outermost circle is 90 degrees.

In FIG. 11, there are a total of 13 peaks showing the peak of the absolute gain on the x-axis where the antenna elements are arranged, that is, on the straight line connecting φ from 0 degrees to 180 degrees,
There is only one mountain on the y-axis that is orthogonal to the axis where the antenna elements are arranged, that is, on the straight line that connects φ with 90 degrees and 270 degrees. Hereinafter, a mountain with a zenith angle θ of 0 is referred to as a main beam, a mountain with a zenith angle θ of other than 0 is referred to as a side lobe, and a valley between mountains is referred to as a null point. In this way, when the antenna elements are arranged on a straight line in the azimuth direction in which the satellite is located, the directional characteristics in the plane cut by the straight line become sharp, and the null point and side Robes and alternates appear.

Further, FIG. 12 shows a directivity characteristic diagram in the case where the directivity characteristic in FIG. 11 is cut by a straight line connecting φ and 0 °. In FIG. 12, the horizontal axis represents the zenith angle θ, and the vertical axis represents the absolute gain which is a unit of the intensity of the radiated radio wave. As can be seen from FIG. 12, the null points, which are the valleys of the radio field intensity, are formed at approximately 8.8 degrees and 13.2 degrees of the zenith angle. According to the present embodiment, as described above, since the null point determines the interval between the antenna elements so as to match the direction of the satellite at the position adjacent to the target satellite, It does not receive radio waves from a certain satellite and is not affected by them.

Similarly, the directional characteristics of the array antenna when 16 antenna elements shown in FIG. 9 are arranged are shown in FIG.
FIG. 1 shows the directional characteristics of the array antenna having the 32 element × 16 element antenna element array shown in FIG.
5 and FIG. Comparing the directional characteristics shown in FIGS. 11 and 13, when the number of antenna elements is increased from 8 elements to 16 elements, the directional characteristics (the distance between the side lobe and the null point) become more dense on the x-axis. You can see that
On the other hand, it can be seen that the directional characteristics on the y-axis do not change between 8 elements and 16 elements. In FIG. 14, as in FIG.
FIG. 14 is a directional characteristic diagram when the directional characteristic in FIG. 13 is cut by a straight line connecting φ with 0 degrees and 180 degrees. In FIG. 14, the null point, which is a valley of the radio field intensity, is approximately 4.4 of the zenith angle.
It can be seen that the degree is 8.8 degrees and 13.2 degrees.

Further, in FIGS. 15 and 16, x
Since the antenna elements of 32 elements on the axis and 16 elements on the y axis are arranged in a grid pattern, in the directional characteristic diagram shown in FIG. 15, φ is 0 ° and 180 °, and φ is 90 °. It can be seen that the intervals between the side lobes and the null points appear closely in both the direction connecting the degrees and 270 degrees. Figure 1
6, the directional characteristics in FIG.
The directional characteristic figure when it cuts by the straight line which connects 0 degree and 180 degrees is shown. In FIG. 16, the second null point is located at a position where the zenith angle θ is 4.4 degrees, and the fourth null point is located at a position where the zenith angle θ is 8.8 degrees.
It can be seen that there is a sixth null point at the 13.2 degree position. At this time, the directional characteristic diagram on the straight line connecting φ between 90 degrees and 270 degrees is almost the same as the directional characteristic diagram shown in FIG.

As described above, by increasing the number of antenna elements, the directional characteristics of the antenna (the distance between the side lobe and the null point) can be made close. Furthermore, by arranging the antenna elements in a grid pattern, the directional characteristics of the antenna can be made dense in both the x-axis and the y-axis directions.

Next, a second embodiment will be described. Figure 5
A conceptual diagram in the second embodiment is shown in FIG. In the second embodiment, the case where the antenna element and the feeding circuit are arranged on the same substrate is shown. In FIG. 5, 42 is an antenna element, for example, a square patch antenna element. Reference numeral 47 denotes a dielectric substrate or film on which the feed line 43 and the patch antenna 42 are arranged. 43 is
The feeding line 46 formed of a strip line is a conductive plate, and is arranged above the substrate 47 with a certain space. The conductive plate 46 may be grounded or may not be grounded. 48 is a conductive plate,
It is arranged below the film 47 with a certain space and is grounded. Reference numeral 49 denotes a slot opened corresponding to the position where the patch antenna element 42 is arranged on the conductive plate 46. Each slot is located above the position where the patch antenna element 42 is arranged.

Also in the array antenna of this embodiment, in order to reduce the radio wave interference received by the receiver or the transmitter / receiver from a specific direction, or to reduce the radio wave interference given to the satellite in a specific direction, The element spacing of the antenna element 42 is determined based on the equation 5. Further, in FIG. 5, conductor plates 46 and 48 are arranged above and below a substrate 47 on which a power feeding circuit and an antenna element are formed in order to eliminate radiation loss from the power feeding circuit, with a certain space therebetween. The plates of these conductors may be omitted. Further, in the configuration shown in FIG. 5, the feeding circuit may be formed on a substrate different from the substrate forming the antenna element, and as shown in FIG. 1, the pins may be fed to the antenna element. Power may be supplied using through holes. In addition, a conductor plate is arranged through a certain space between the board forming the power feeding circuit and the board forming the antenna element, and a slot is provided between the antenna element and the power feeding circuit. Power may be supplied by electromagnetic field coupling.

In the first and second embodiments described above, the antenna element is a square patch antenna element,
The same can be said when the antenna element is a circular patch antenna element or another antenna element such as a helical antenna. Further, as the array spacing, the array spacing is determined based on the equation 5 only in the horizontal direction and the vertical direction, but the antenna element arrayed on the diagonal line of the square or the rectangle is also based on the equation 5 similarly. Can also be determined.

Further, in the first and second embodiments, the feeding points for the antenna elements are fed from the same direction, but the feeding can be done from different directions by changing the length of the feeding line. It is also possible to make the feeding phases for the elements equal. In addition, in the configuration shown in FIG.
Conductive plates 49 and 48 are arranged above and below a film 47, in which the feeding circuit 43 and the antenna element 42 are formed, with a certain space in between. The space is filled with a dielectric material. Also does not affect the method of determining the sequence spacing. By filling the dielectric material, it is possible to improve the efficiency of feeding power to the antenna element and reduce the size of the antenna element.

When the coaxial waveguide converter is used for feeding the antenna from the receiver or the transceiver, it is necessary to remove the antenna element for that purpose and the antenna element for processing the outer shape. In this case, the antenna element interval may be determined by first taking into consideration the omission of the antenna elements. In this case, the antenna element spacing is basically determined by the _{equation 5} , but the array factor calculation taking into consideration all the antenna elements is performed by finely changing the antenna element spacing, so that a certain direction θ _{0 can} be obtained. By determining the antenna element spacing when the received power becomes the smallest, it is possible to obtain a stricter optimal element spacing.

According to each of the above embodiments, the area of the antenna is reduced, and at the same time, the antenna elements are fed with the same phase and the same amplitude, so that the structure of the receiver can be simplified.

[0051]

EFFECTS OF THE INVENTION By determining the distance between the antenna elements as described above, the received power of the interference radio wave from the communication satellite in the direction of the adjacent satellite can be reduced while keeping the feeding amplitude to each antenna element equal, or It is possible to reduce the interference radio wave given to the communication satellite in the direction of the adjacent satellite.
As a result, a receiver equipped with the antenna of the present invention, or
The interference resistance of the transceiver is improved, and the load of identifying the desired signal required by the receiver or the transceiver can be reduced. Further, compared with an antenna having the same capability, since the antenna elements are fed with equal amplitude, the antenna efficiency is increased and an antenna with a small area becomes possible.

[Brief description of drawings]

FIG. 1 is a conceptual diagram in the case where a power supply circuit is configured on a substrate different from a substrate that configures an antenna element in the first embodiment.

FIG. 2 is an external view of a parabolic antenna using a main reflecting mirror having a parabolic surface according to a conventional technique.

FIG. 3A is a configuration diagram of an array antenna in which feeding amplitudes are made nonuniform with respect to each antenna element according to a conventional technique.
(B) A configuration diagram of a power supply circuit for making the power supply amplitude nonuniform with respect to each antenna element by a conventional technique.

FIG. 4 is an explanatory diagram showing coordinate axes of an array antenna.

FIG. 5 is a conceptual diagram when a feeding circuit is formed on the same substrate as a substrate that constitutes an antenna element in the second embodiment.

FIG. 6 is a conceptual diagram of directional characteristics of an antenna configured by a conventional technique.

FIG. 7 is a conceptual diagram of directional characteristics of an antenna configured according to the present invention.

FIG. 8 is a layout diagram of antennas in the case of eight elements in the embodiment.

FIG. 9 is a layout diagram of antennas in the case of 16 elements in the example.

FIG. 10 is a layout diagram of antennas in the case of 32 elements × 16 elements in the example.

FIG. 11 is a far-field directional characteristic diagram of radio waves radiated from the antenna element array shown in FIG.

FIG. 12 is a far-field directional characteristic diagram of radio waves radiated from the antenna element array shown in FIG.

13 is a far-field directional characteristic diagram of radio waves radiated from the antenna element array shown in FIG.

14 is a far-field directional characteristic diagram of radio waves radiated from the antenna element array shown in FIG.

15 is a far-field directional characteristic diagram of radio waves radiated from the antenna element array shown in FIG.

16 is a far-field directional characteristic diagram of radio waves radiated from the antenna element array shown in FIG.

[Explanation of symbols]

10 ... Receiver or transceiver, 11.47.31 ... Dielectric substrate or film, 12.42.32 ... Antenna element, 13.33.43 ... Feed line, 111 ... Feed point, 1
12 ... pin or through hole, 21 ... main reflecting mirror, 22
... Feed horn, 23 ... Sub-reflecting mirror, 24 ... Supporting material for supporting the sub-reflecting mirror, 34 ... Unequal distributor or unequal distribution circuit, 3
Reference numeral 5 ... Equal distributor or equal distribution circuit, 46 ... Conductive plate, 48 ... Arranged over a certain space above a dielectric substrate or film 47 in which an antenna element and a feeding circuit are formed on the same substrate. An electrically conductive plate disposed above a dielectric substrate or film 47 on which the antenna element and the feeding circuit are formed on the same substrate, and a conductive plate 49, a conductive plate 46, and an antenna element 42 above the antenna element 42. Slots that are opened in the positions where they are located, 61.71 ... Communication satellites in which transceivers equipped with antennas communicate, 62.72 ... Communication satellites located at adjacent satellite positions, 63.73 ... Aperture plane of antennas, 64
74 ... Directivity characteristic indicating the strength of the radio wave that can be radiated or received from the antenna.

Claims (12)

[Claims] 1. An array antenna having a plurality of antenna elements and a feed line for feeding each of the plurality of antenna elements, wherein the feed line has a feed amplitude and a feed amplitude for each of the plurality of antenna elements. Power is fed with the same feeding phase, and the number of the plurality of antenna elements and the interval between the antenna elements are determined so as not to receive radio waves from other communication partners other than the intended communication partner. An array antenna, wherein the plurality of antenna elements are arranged according to the determined number of antenna elements and the spacing between the antenna elements. 2. The array antenna according to claim 1, wherein the plurality of antenna elements are arranged on a straight line. 3. The array antenna according to claim 1, wherein the plurality of antenna elements are arranged in a grid pattern. 4. The array antenna according to claim 3, wherein the vertical and horizontal intervals of the lattice are equal to the determined intervals between the antenna elements. 5. The conductive element according to claim 1, wherein the plurality of antenna elements and the feed line are formed on the same substrate, and the lower portion of the substrate is arranged in parallel with the substrate through a predetermined space. And a conductive plate that is arranged in parallel to the substrate through a predetermined space on the upper side of the substrate and has slots formed at positions corresponding to the plurality of antenna elements, respectively. An array antenna characterized by being provided. 6. The antenna element according to claim 5, which is arranged in parallel with the substrate through a predetermined space on an upper part of a conductive plate in which the slot is opened and which is provided at a position corresponding to each of the slots. An array antenna further comprising a conductive plate on which is arranged. 7. The array antenna according to claim 5, wherein at least one of the predetermined space between the lower portion and the upper portion of the substrate is filled with a dielectric material. 8. The antenna element according to claim 1, wherein the plurality of antenna elements are formed on a first substrate, and the feed line is provided below the first substrate via the first space through a predetermined space. On a second substrate arranged parallel to the substrate, and is arranged parallel to the first substrate through a predetermined space between the first substrate and the second substrate, An array comprising: a conductive plate having any one of a pin, a through hole, and a slot at a position corresponding to each of the plurality of antenna elements so as to supply power to each of the plurality of antenna elements. antenna. 9. The communication partner according to claim 1, wherein the target communication partner is a direction in which a communication satellite performing communication is located, and the other communication partner other than the target communication partner does not communicate. An array antenna characterized by being a communication satellite. 10. An array antenna in which a plurality of antenna elements are arranged in a grid pattern is provided with a power supply circuit that supplies power to each of the plurality of antenna elements with equal power supply amplitude and power supply phase, and at least the grid pattern is provided. The number of antenna elements on one side and the spacing between the antenna elements are determined according to the directional characteristics such that radio waves from a plurality of predetermined directions are not received, and the determined number of antenna elements and the spacing between the antenna elements. An array antenna, wherein the plurality of antenna elements are arranged according to 11. A receiving device comprising: a plurality of antenna elements; a power feeding line for feeding power to each of the plurality of antenna elements; and a receiving section for receiving a signal received by the antenna element. , Each of the plurality of antenna elements is fed with the same feed amplitude and feed phase, and the number of the plurality of antenna elements and the spacing between the antenna elements are different from each other than the intended communication partner. A receiving apparatus, characterized in that it is determined not to receive a radio wave from a communication partner, and the plurality of antenna elements are arranged according to the determined number of antenna elements and the spacing between the antenna elements. 12. A method for determining a directivity characteristic in an array antenna in which a plurality of antenna elements are arrayed, wherein the feed amplitude and feed phase are made equal to each of the plurality of antenna elements, and the feed is performed. The main lobe for communicating with the communication satellite is defined, and the number of the plurality of antenna elements is set so that the directional characteristic becomes a null point with respect to the direction in which a communication satellite other than the target communication satellite exists. And a spacing between the antenna elements, and arranging the plurality of antenna elements according to the determined number of antenna elements and the spacing between the antenna elements.