JPH1075117A - Antenna device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simultaneously form plural beams with a small arithmetic calculation amount in simple constitution by connecting a linear digital beam formation device to an element antenna parallel to the arraying direction of a triangle grid for arraying the element antenna and a reception conversion part. SOLUTION: The element antenna 1a-1l are arranged in a triangle array. The respective reception conversion parts 2a-2l amplify electromagnetic waves received in the respective element antennas 1a 1l, convert them to digital signals, and output them to first stage linear digital beam formation devices 5a-5d. The respective beam formation devices 5a-5d input signals from the element antenna on a grid parallel to an x-axis, execute a beam formation processing, form plural sector beams in a direction vertical-to a y-axis and respectively output them to second stage linear digital beam formation devices 6a-6c. In the respective beam formation devices 6a-6c, the beam formation processing is executed to the inputted signals, and the plural beams are formed in the direction vertical to the x'-axis and outputted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an element antenna for receiving electromagnetic waves arranged in a triangular lattice, a reception converter for converting an analog reception signal of an electromagnetic wave received by each of the element antennas into a digital signal, The present invention relates to an antenna apparatus including a two-dimensional digital beamformer that digitally performs an arithmetic operation on a digital reception signal converted in each reception conversion unit and simultaneously forms a plurality of beams.

[0002]

2. Description of the Related Art FIGS. 7 and 8 are block diagrams of a conventional antenna device. FIG. 7 is a diagram showing an overall configuration, and FIG. 8 is a diagram showing an arrangement of element antennas and a connection to a digital beamformer when the antenna aperture is viewed from the front. In the figure, reference numerals 1a to 1l denote element antennas arranged in a triangular lattice on the opening surface of the antenna device to receive electromagnetic waves.
Reference numerals a to 21 denote reception converters provided for the element antennas 1a to 1l, respectively, for amplifying received analog signals of electromagnetic waves and converting the signals into digital signals. Reference numerals 3a to 31 denote signals corresponding to the case where the amplitude of the received signal is zero. A beam forming process for the digital reception signals from the reception conversion units 2a to 2l and the zero signal from the zero signal output circuits 3a to 3l to simultaneously output the reception beams in a plurality of directions. The two-dimensional digital beamformers 5a to 5f and 6a to 6d are one-dimensional digital beamformers constituting the two-dimensional digital beamformer 4, and 5a to 5f are digital signals from the reception conversion units 2a to 2l. The beamforming process is performed on the received signal converted into the zero signal and the zero signal from the zero signal output circuits 3a to 3l, as shown in FIG. First stage one-dimensional digital beamformer to simultaneously form a plurality of beams in the axial direction perpendicular 6
a to 6d are first-stage one-dimensional digital beamformers 5a
This is a second-stage one-dimensional digital beamformer that performs beam forming processing on signals output from .about.5f to simultaneously form a plurality of beams in a direction perpendicular to the x-axis shown in FIG.

FIG. 9 is a diagram showing the distribution of the directional directions of a plurality of beams formed by a conventional antenna device. In the figure, 7a to 7i are -3 dB coverage areas of the beam formed by the antenna device, and 8a to 8d are low level areas.

FIG. 10 is a diagram showing an arrangement of the element antennas 1a to 1l and a coordinate system representing the directivity of a beam to be formed.

Next, the operation of the conventional antenna device will be described. The element antennas 1a to 1l are arranged in a triangular arrangement as shown in FIG. 8 in order to configure antenna apparatuses having the same aperture diameter with the same lattice interval and a smaller number of element antennas than the square arrangement. As shown in FIG. 8, each element antenna is arranged at every other lattice point on a rectangular lattice parallel to the x-axis and the y-axis to form a triangular lattice. Each of the receiving converters 2a to 2l amplifies an electromagnetic wave received by each of the element antennas 1a to 1l, converts it into a digital signal, and outputs the digital signal to the first-stage one-dimensional digital beamformers 5a to 5f. Each of the first-stage one-dimensional digital beamformers 5a to 5f receives signals from element antennas on a lattice parallel to the x-axis in the figure, and outputs amplitudes from zero signal output circuits 3a to 3l at lattice points where no element antenna exists. Is input to the input digital signal, and a beam forming process is performed on the input digital signal in accordance with "Equation 1" to form a plurality of fan-shaped beams in the direction corresponding to the output number r perpendicularly to the y-axis in FIG. Second stage one-dimensional digital beamformers 6a-6
d. In the second-stage one-dimensional digital beamformers 6a to 6d, a signal input from the first-stage one-dimensional digital beamformer is subjected to beam forming processing according to "Equation 2", and corresponds to the output number s perpendicular to the x-axis. A plurality of beams are formed in the specified directions. Therefore, the equation representing the beam formed by the two-dimensional beamformer configured so as to be orthogonally crossed by the first-stage one-dimensional digital beamformer and the second-stage two-dimensional digital beamformer is expressed by “Equation 3”. Become like In this way, the digital beamforming antenna device can simultaneously form a plurality of reception beams and exhibit desired functions and performance.

[0006]

(Equation 1)

[0007]

(Equation 2)

[0008]

(Equation 3)

For example, in a four-input first-stage one-dimensional digital beamformer 5a, reception signals from element antennas 1a and 1b on a grid parallel to the x-axis are input to m = 0 and 2 inputs. , 2b, and converted into a digital signal. The remaining inputs of m = 1, 3 are equivalently input from the zero signal output circuits 3a, 3b with a signal having an amplitude of 0 corresponding to a state where there is no received signal. The beam forming process is performed according to "Equation 1" to form a plurality of fan-shaped beams in a direction perpendicular to the y-axis in FIG. 6c. Similar processing is performed in the first-stage one-dimensional digital beamformers 5b to 5f. At this time, the directional cosine of the directional directions of the plurality of beams formed in the first-stage one-dimensional digital beamformers 5a to 5f with respect to the x-axis can be obtained from "Equation 1" as "Equation 4". In the second-stage one-dimensional digital beamformer 6a, the output of r = 0 from the first-stage one-dimensional digital beamformer 5a is input from the input of n = 0, and the first-stage one-dimensional digital beamformers 5b to 5b are input. One output each of r = 0 from 5f is input from each input of n = 1 to 5, and "
According to Equation 2 ", a plurality of beams are formed perpendicularly to the x-axis in FIG. 7 in the directions respectively corresponding to the output numbers s, and are respectively output. The same processing is performed in the second-stage one-dimensional digital beamformers 6b to 6d. At this time, the direction cosine of the directional directions of the plurality of beams formed in the second-stage two-dimensional digital beamformers 6a to 6d with respect to the y-axis can be obtained from "Equation 2" as "Equation 5". Therefore, the directional directions of the formed beam are output numbers r and s.
Can be calculated using Equations 4 and 5 and the distribution of the directional directions of the plurality of beams formed is a square distribution as shown in FIG. FIG. 9 shows a coverage area of −3 dB value of only 9 beams around the front direction of the antenna device. The coordinate system of the beam directional direction used in FIG.
0.

[0010]

(Equation 4)

[0011]

(Equation 5)

[0012]

Since the conventional antenna device is configured as described above, in order to perform a two-dimensional digital beam forming process when the element antennas are arranged in a triangular form, the number of element antennas is twice as large. There is a problem that a two-dimensional digital beamformer having the number of inputs is required, the number of arithmetic processings is increased, and the hardware scale is increased.

The arrangement of the plurality of beams formed in the space is a square array as shown in FIG. 6, but in such an arrangement of the beams, a hatched line is shown between the beams 7a to 7i. However, there is a problem that low-level areas 8a to 8d having low reception levels that cannot be covered with 3 dB exist.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems. A plurality of beams can be simultaneously formed with a small amount of calculation with a simple configuration while forming a triangular arrangement of element antennas. It is an object of the present invention to obtain an antenna device capable of reducing a region where a beam crossing level is low by making a spatial arrangement of a plurality of beams into a triangular arrangement.

[0015]

An antenna apparatus according to a first aspect of the present invention includes a two-dimensional digital beamformer, which performs a beamforming process in each dimension with a one-dimensional digital beamformer by using orthogonal x-axis and y-axis. A device configured to be connected to an element antenna and a reception conversion unit parallel to the arrangement direction of a triangular lattice in which element antennas forming an antenna device aperture are arranged without being connected to an element antenna and a reception conversion unit parallel to two axes. It is.

Further, an antenna device according to a second aspect of the present invention includes:
Without connecting a one-dimensional digital beamformer that performs beamforming processing in each dimension of the two-dimensional digital beamformer to an element antenna parallel to two orthogonal x-axis and y-axis and a receiving conversion unit, Device antenna parallel to the arrangement direction of the triangular lattice in which the element antennas constituting the device aperture are arranged and connected to the receiving conversion unit, and further, a part of the element antennas is omitted and a zero signal output device is arranged. It is.

Further, an antenna device according to a third aspect of the present invention includes:
Without connecting a one-dimensional digital beamformer that performs beamforming processing in each dimension of the two-dimensional digital beamformer to an element antenna parallel to two orthogonal x-axis and y-axis and a receiving conversion unit, It is configured to be connected to the element antenna and the reception conversion unit parallel to the arrangement direction of the triangular lattice in which the element antennas constituting the device aperture are arranged, and a zero signal output device is arranged by omitting some element antennas,
Further, each of the one-dimensional digital beamformers constituting the two-dimensional digital beamformer is provided with a power-of-two input / output number.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment 1 FIG. 1 and 2 are configuration diagrams of a first embodiment of the present invention. FIG. 1 is a diagram showing an overall configuration, and FIG. 2 is a diagram showing an arrangement of element antennas and a connection to a digital beamformer when the antenna aperture is viewed from the front.
In the figure, reference numerals 1a to 1l denote element antennas arranged in a triangular lattice on the antenna opening surface to receive electromagnetic waves, and 2a to 1l.
Reference numeral 2l denotes a reception converter provided for each of the element antennas 1a to 1l for amplifying an electromagnetic wave to be received and converting the received electromagnetic wave into a digital signal, and 4 combines digital reception signals from the reception converters 2a to 2l and simultaneously transmits signals in a plurality of directions. Two-dimensional digital beamformers 5a to 5f and 6a to 6d for forming reception beams are one-dimensional digital beamformers constituting the two-dimensional digital beamformer 4, and 5a to 5d.
Is a first-stage one-dimensional digital beam forming for simultaneously forming a plurality of beams in a direction perpendicular to the y-axis shown in the figure by performing beam forming processing on the received signals converted into digital signals from the receiving converters 2a to 2l. And 6a to 6c perform a beam forming process on the signals output from the first-stage one-dimensional digital beamformers 5a to 5d to simultaneously form a plurality of beams in a direction perpendicular to the x 'axis shown in FIG. It is a one-dimensional digital beamformer.

FIG. 3 is a diagram showing the distribution of the directional directions of a plurality of beams formed using the first embodiment. In the figure, reference numerals 7a to 7g denote coverages of the beam formed by the antenna device at -3dB.

The operation of the antenna device configured as described above will be described. The element antennas 1a to 1l are arranged in a triangular arrangement as shown in FIG. 2 in order to form antenna devices having the same aperture diameter with the same lattice interval and fewer element antennas than the square arrangement. Each of the receiving converters 2a to 2l amplifies an electromagnetic wave received by each of the element antennas 1a to 1l, converts it to a digital signal, and outputs the digital signal to the first-stage one-dimensional digital beamformers 5a to 5d. Each of the first-stage one-dimensional digital beamformers 5a to 5d receives a signal from an element antenna on a lattice parallel to the x'-axis in the drawing and forms a beam on the input digital signal according to "Equation 6". Processing is performed to form a plurality of fan-shaped beams in a direction perpendicular to the y-axis in the figure and corresponding to the output number r, respectively, and output to the second-stage one-dimensional digital beamformers 6a to 6c. In each of the second-stage one-dimensional digital beamformers 6a to 6c, a signal input from the first-stage digital beamformer is subjected to beam forming processing in accordance with "Equation 7", and output signals s are respectively perpendicular to the x 'axis. A plurality of beams are formed and output in corresponding directions. Therefore, the equation expressing the beam formed by the two-dimensional beamformer formed obliquely by the first-stage one-dimensional digital beamformer and the second-stage two-dimensional digital beamformer is represented by "Equation 8". become that way. In this way, the digital beamforming antenna can simultaneously form a plurality of reception beams and exhibit desired functions and performance.

[0021]

(Equation 6)

[0022]

(Equation 7)

[0023]

(Equation 8)

For example, in the three-input first-stage one-dimensional digital beamformer 5a, the element antennas 1a, 1a arranged in parallel with the inputs of m = 0, 1, 2 in the x'-axis direction.
b, 1c are received by the reception converters 2a, 2b, 2c
The digital signal is converted into a digital signal through the input, and is subjected to beam forming processing according to "Equation 6" to form a plurality of fan-shaped beams in a direction perpendicular to the y-axis in FIG. Output to the one-dimensional digital beamformers 6a to 6c. Similar processing is performed in the first-stage one-dimensional digital beamformers 5b to 5d. At this time, the first-stage one-dimensional digital beamformers 5a to 5d
The direction cosine of the directional directions of the plurality of beams formed at the x-axis is expressed by “Equation 9” from “Equation 6” and “Equation 7”.
Can be requested. In the second-stage one-dimensional digital beamformer 6a, the output of r = 0 from the first-stage one-dimensional digital beamformer 5a is input from the input port n = 0, and the first-stage one-dimensional digital beamformer 5b
N = 1 to 3 for each output of r = 0 from to 5d
And input according to "Equation 7".
A plurality of beams are formed in a direction perpendicular to the x 'axis in FIG. 1 in directions corresponding to the output numbers s, and output. Similar processing is performed in the second-stage one-dimensional digital beamformers 6b and 6c.
It is performed in. At this time, the direction cosine of the directional directions of the plurality of beams formed in the second-stage one-dimensional digital beamformers 6a to 6c with respect to the y-axis can be obtained as "Equation 10" from "Equation 7". Therefore, the directional direction of the beam to be formed is represented by "Equation 9" from the output numbers r and s.
And "Equation 10", and the distribution of the directional directions of the plurality of beams formed is a triangular distribution as shown in FIG. FIG. 3 shows a coverage of a −3 dB value of only seven beams around the front of the antenna device. The coordinate system of the beam directional direction used in FIG. 3 is shown in FIG.

[0025]

(Equation 9)

[0026]

(Equation 10)

Embodiment 2 FIG. Next, as in the second embodiment shown in FIGS. 4 and 5, some of the element antennas 1 and the reception converter 2
And the case where the zero signal output devices 3a and 3b are used will be described. In this case, for example, in a three-input first-stage one-dimensional digital beamformer 5a, m = 0, 1,
Element antennas 1 arranged in parallel to the input of
Signals from a and 1b are input, and a signal having an amplitude of 0 equivalent to a state in which no received signal is equivalently input from the zero signal output circuit 3a is input to the input of m = 3, and the beam forming process is performed according to "Equation 6". Output number r perpendicular to the y-axis in the figure.
And a plurality of fan-shaped beams are formed in the directions respectively corresponding to the first and second stage one-dimensional digital beamformers 6a to 6c. Similar processing is performed in the first-stage digital beamformers 5b to 5f. At this time, the direction cosine of the directional directions of the plurality of beams formed by the first-stage one-dimensional digital beamformers 5a to 5f with respect to the x-axis can be obtained as "Equation 9" from "Equation 6" and "Equation 7". it can. In the second-stage one-dimensional digital beamformer 6a, the first-stage one-dimensional digital beamformers 5a to
Each output of r = 0 of the output from 5c is set to n = 0
3, and a plurality of beams are formed in a direction perpendicular to the x 'axis in the figure and in a direction corresponding to the output number s according to "Equation 7" and output. Similar processing is performed in the second stage digital beamformers 6b and 6c. At this time, the second stage digital beamformers 6a-
The direction cosine of the directional directions of the plurality of beams formed in 6c with respect to the y-axis can be obtained as "Equation 10" from "Equation 7". Therefore, the directional directions of the formed beams can be calculated from the output numbers r and s using “Equation 9” and “Equation 10”, and the distribution of the directional directions of the formed beams is triangular as shown in FIG. Distribution. Further, the shape of the formed beam is adjusted to a desired shape because the aperture shape of the entire antenna device is adjusted using the zero signal output circuits 3a and 3b.

Embodiment 3 Next, Embodiment 3 of FIG.
As described above, some element antennas 1 and the reception conversion unit 2 are omitted, the zero signal output device 3 is used, and the number of inputs of the one-dimensional digital beamformer of each dimension of the two-dimensional digital beamformer is further reduced to two. The following describes a case in which the power is raised to the power of In this case, for example, in the first-stage one-dimensional digital beamformer 5a having 8 inputs, x ′ is input to the inputs of m = 0 to 3.
Received signals from the element antennas 1a to 1d arranged in parallel in the axial direction are converted into digital signals through the reception converters 2a to 2d and input, and the remaining m = 4 to 7 are input to the zero signal output circuit 3a. 3d, a signal having an amplitude of 0 corresponding to a state where there is no received signal is input, and a beam forming process is performed according to "Equation 6", and the beam forming process corresponds to the output number r perpendicular to the y-axis in FIG. A plurality of fan-shaped beams are formed in the directions and output to the second-stage one-dimensional digital beamformer. Similar processing is performed in the first-stage digital beamformers 5b to 5h. At this time, the direction cosine of the directional directions of the plurality of beams formed in the first-stage digital beamformers 5a to 5h with respect to the x-axis is "
It can be obtained from Equations 6 "and 7" as Equation 9. In the second-stage one-dimensional digital beamformer 6a, one output of each of the outputs from the first-stage one-dimensional digital beamformers 5a to 5h is provided. Are input to the respective inputs of n = 0 to 7, and a plurality of beams are formed in the direction corresponding to the output number s perpendicularly to the x'-axis in the figure according to "Equation 7" and output. Similar processing is performed in the second-stage digital beamformers 6b to 6h, at this time, the second-stage one-dimensional digital beamformers 6a to 6h.
The direction cosine of the directional directions of the plurality of beams formed in h with respect to the y-axis can be obtained as "Equation 10" from "Equation 7". Accordingly, the directional directions of the formed beams can be calculated from the output numbers r and s using “Equation 9” and “Equation 10”, and the distribution of the directional directions of the plurality of formed beams is as shown in FIG. It becomes triangular distribution. Further, the shape of the formed beam is adjusted to a desired shape because the aperture shape of the entire antenna device is adjusted using the zero signal output circuits 3a and 3b.

Embodiment 4 In addition, the first embodiment
3, the case where the two-dimensional digital beamformer 4 is configured by connecting the hardware of the one-dimensional digital beamformer in two stages has been described. The same effect can be obtained also when using the configuration.

Embodiment 5 In addition, the first embodiment
4, the case where the number of inputs and outputs of the two-dimensional digital beamformer 4 is 3 rows and 4 columns or 8 rows and 8 columns has been described, but by using a two-dimensional digital beamformer having an arbitrary number of inputs and outputs, The same effect can be obtained when an arbitrary number of element antennas, reception converters, and zero signal output circuits are used.

Embodiment 6 FIG. In addition, the first embodiment
5, a case has been described where the signal received by the element antenna 1 is converted into a digital signal by the reception conversion unit 2 and the reception digital beam is formed by the two-dimensional digital beamformer 4. The same effect can be obtained when the transmission digital beam forming for transmitting from the element antenna 1 is performed by using the device for converting the digital transmission signal generated in the two-dimensional digital beamformer 4 into the analog transmission signal without using the same. .

[0032]

According to the first invention, the two-dimensional digital beamformer 4 is replaced with the one-dimensional digital beamformers 5, 6.
Are connected in parallel to the two sides of the triangular lattice where the element antennas are arranged, thereby realizing an antenna device of the same size with the same number of element antennas using a beamformer with a smaller number of inputs and outputs compared to conventional devices. Therefore, the size of the arithmetic processing unit of the digital beamformer can be reduced, and the distribution of the directional directions of a plurality of beams to be formed can be arranged in a triangular array, so that the reception level is low. There is an effect that the low level area can be reduced.

According to the second invention, the two-dimensional digital beamformer 4 is connected to the one-dimensional digital beamformers 5 and 6 in parallel to two sides of a triangular lattice in which element antennas are arranged, respectively. By omitting a part of the element antenna 1 and the reception conversion unit 2 in the peripheral portion of the opening and adjusting the shape of the opening of the entire antenna device using the zero signal output circuit 3, the same scale of the antenna device having the same number of element antennas is obtained. Since the antenna device can be realized by using a smaller number of input / output beamformers as compared with the conventional device, the effect of reducing the scale of the arithmetic processing unit of the digital beamformer is obtained. Because the distribution of the beam directivity direction can be arranged in a triangular array,
There is an effect that the low-level region where the reception level is low can be reduced, and the shapes of a plurality of beams to be formed can be shaped into a desired shape.

According to the third aspect of the present invention, the two-dimensional digital beamformer 4 is connected to the one-dimensional digital beamformers 5 and 6 in parallel to two sides of a triangular lattice in which element antennas are arranged. By omitting a part of the element antenna 1 and the reception conversion unit 2 in the peripheral portion of the opening and adjusting the shape of the opening of the entire antenna device using the zero signal output circuit 3, the same scale of the antenna device having the same number of element antennas is obtained. Since the antenna device can be realized by using a smaller number of input / output beamformers as compared with the conventional device, the effect of reducing the scale of the arithmetic processing unit of the digital beamformer is obtained. Because the distribution of the beam directivity direction can be arranged in a triangular array,
There is an effect that the low-level region where the reception level is low can be reduced and the beam shape can be shaped into a desired shape. Further, by making the number of inputs and outputs of the one-dimensional digital beamformers 5 and 6 a power of two,
An efficient arithmetic algorithm such as fast Fourier transform can be used for the arithmetic processing of the digital beamformer, so that the scale of the arithmetic processing unit can be further reduced and the beam shape is increased by increasing the number of inputs and outputs of the beamformer. However, there is an effect that the number of beams increases and the low-level region further decreases without changing.

[Brief description of the drawings]

FIG. 1 is a first embodiment of an antenna device according to the present invention;
FIG.

FIG. 2 is a first embodiment of the antenna device according to the present invention;
FIG. 5 is a diagram showing an array of element antennas.

FIG. 3 is a diagram showing an arrangement of a plurality of beams formed using the antenna device according to the present invention.

FIG. 4 is a second embodiment of the antenna device according to the present invention;
FIG.

FIG. 5 is a second embodiment of the antenna device according to the present invention;
FIG. 5 is a diagram showing an array of element antennas.

FIG. 6 is a third embodiment of the antenna device according to the present invention;
FIG. 5 is a diagram showing an array of element antennas.

FIG. 7 is an overall configuration diagram of a conventional antenna device.

FIG. 8 is a diagram showing an arrangement of element antennas of a conventional antenna device.

FIG. 9 is a diagram showing an arrangement of a plurality of beams formed using a conventional antenna device.

FIG. 10 is a diagram showing a coordinate system used in a configuration diagram of an antenna device according to the present invention and a conventional antenna device and a diagram showing an arrangement of a plurality of beams to be formed.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Element antenna 2 Reception conversion part 3 Zero signal output circuit 4 Two-dimensional digital beamformer 5 First-stage one-dimensional digital beamformer 6 Second-stage one-dimensional digital beamformer 7 Beam coverage 8 Low level area

Claims (3)

[Claims] 1. An element antenna arranged in a triangular lattice and receiving an electromagnetic wave, a reception conversion section for converting an analog reception signal of the electromagnetic wave received by each of the element antennas into a digital signal, and a conversion in each of the reception conversion sections And a two-dimensional digital beamformer for simultaneously forming a plurality of beams by digitally performing an arithmetic operation on the received digital received signal, wherein the two-dimensional digital beamformer is for vertical scanning. The first-stage one-dimensional digital beamformer and the second-stage one-dimensional digital beamformer for oblique scanning are arranged so that two-dimensional one-dimensional digital beamformers cross each other. The direction in which the digital beamformer is connected to each of the above-mentioned element antennas and each of the receiving / converting sections is defined by the above-mentioned element antenna. An antenna device having a direction parallel to two sides of a triangular lattice in which antennas are arranged. 2. An element antenna arranged in a triangular lattice and receiving an electromagnetic wave, a reception conversion section for converting an analog reception signal of the electromagnetic wave received by each element antenna into a digital signal, and a conversion in each of the reception conversion sections. And a two-dimensional digital beamformer for simultaneously forming a plurality of beams by digitally performing an arithmetic operation on the received digital received signal, wherein the two-dimensional digital beamformer is for vertical scanning. The first-stage one-dimensional digital beamformer and the second-stage one-dimensional digital beamformer for oblique scanning are arranged so that two-dimensional one-dimensional digital beamformers cross each other. The direction in which the digital beamformer is connected to each of the above-mentioned element antennas and each of the receiving / converting sections is defined by the above-mentioned element antenna. In order to shape the beam formed by adjusting the synthetic aperture shape of the entire antenna device in the direction parallel to the two sides of the triangular lattice where the antennas are arranged,
An antenna device, wherein a part of the element antenna is omitted, and a zero signal output circuit that outputs a signal having an amplitude of 0 equivalent to a state where there is no received signal is disposed equivalently. 3. An element antenna arranged in a triangular lattice and receiving an electromagnetic wave, a reception conversion section for converting an analog reception signal of the electromagnetic wave received by each of the element antennas into a digital signal, and a conversion in each of the reception conversion sections. And a two-dimensional digital beamformer for simultaneously forming a plurality of beams by digitally performing an arithmetic operation on the received digital received signal, wherein the two-dimensional digital beamformer is for vertical scanning. The first-stage one-dimensional digital beamformer and the second-stage one-dimensional digital beamformer for oblique scanning are arranged so that two-dimensional one-dimensional digital beamformers cross each other. The direction in which the digital beamformer is connected to each of the above-mentioned element antennas and each of the receiving / converting sections is defined by the above-mentioned element antenna. In order to shape the beam formed by adjusting the synthetic aperture shape of the entire antenna device in the direction parallel to the two sides of the triangular lattice where the antennas are arranged,
A part of the element antenna is omitted, a zero signal output circuit that outputs a signal of amplitude 0 equivalent to a state where there is no received signal is disposed, and the number of a plurality of beams formed is further increased to increase the number. An antenna apparatus, wherein each one-dimensional digital beamformer is provided with a power-of-two input / output number in order to adjust the directivity direction and reduce the number of arithmetic processing.