JP4515897B2 - Array antenna and its placement method - Google Patents

Description

  The present invention relates to an array antenna that effectively suppresses grating lobes of an array antenna and a method for arranging the array antenna.

  Conventionally, as an array antenna of this type, there is one that controls a pattern of a sub-array antenna in order to suppress a grating lobe in an array antenna constituted by a sub-array antenna (for example, see Patent Document 1). Also, there is an element disclosing method for reducing the number of elements of an array antenna housed in a limited range (see, for example, Patent Document 2).

JP 2003-168912 A JP 9-304499 A

  However, in the former array antenna described above, there is a problem that this cannot be suppressed when the subarray antenna interval is very wide and three or more gratings are generated in the main beam of the subarray antenna. In addition, the latter array antenna is not intended to suppress the grating lobe, but for example, when applied to the arrangement of an array antenna composed of subarray antennas, the grating in the subarray antenna beam is sufficiently suppressed. There is a problem that it cannot be done.

  That is, the conventional array antenna constituted by subarray antennas has a problem of generating grating lobes when the distance between the subarray antennas is wide. Further, in the conventional array antenna for suppressing this, there are problems that the number of grating lobes is large or the grating lobes in the beam of the sub-array antenna cannot be sufficiently suppressed when used in combination with the sub-array antenna.

  The present invention has been made to solve the above-described problems. An array antenna that can effectively suppress the grating in the sub-array beam by changing the interval of the sub-array antenna by a certain increment, and the arrangement thereof. It aims to provide a method.

The array antenna according to the present invention includes a plurality of sub-array antennas composed of a plurality of element antennas, and is arranged so that the interval between the phase centers of adjacent sub-array antennas sequentially increases by a certain amount along the arrangement direction. The increase amount of the interval is set to be smaller than the predetermined increase amount so that the direction of the first grating lobe closest to the main lobe out of the grating lobes is outside the first null of the subarray antenna. It is characterized by.

An array antenna according to another invention includes a plurality of subarray antennas composed of a plurality of element antennas, and a phase center interval between adjacent subarray antennas is equal to a phase center interval between other adjacent subarray antennas. It is arranged so as to increase by a certain amount compared to any one, and the increase amount of the interval is such that the direction of the first grating lobe closest to the main lobe is greater than the first null of the subarray antenna among the grating lobes. It is characterized by being set smaller than a predetermined increase amount so as to be on the outside .

An array antenna according to still another invention includes a plurality of sub- array antennas composed of a plurality of element antennas, and the interval between the phase centers of the adjacent sub-array antennas increases sequentially by a certain amount along the arrangement direction. The increase in the interval is set to a predetermined value so that the direction of the first grating lobe closest to the main lobe among the grating lobes coincides with the first null of the subarray antenna. Features.
In addition, a plurality of sub-array antennas composed of a plurality of element antennas are provided, and the phase center interval between adjacent sub-array antennas is a constant amount compared to any one of the phase center intervals between other adjacent sub-array antennas. The interval increase amount is set to a predetermined value so that the direction of the first grating lobe closest to the main lobe among the grating lobes coincides with the first null of the subarray antenna. It is characterized by that.
Further, in an array antenna having a plurality of columns in which the phase centers of a plurality of subarray antennas composed of a plurality of element antennas are arranged, the interval between the phase centers between adjacent subarray antennas of each column is sequentially increased along the arrangement direction. It is arranged so as to increase by a certain amount, and the interval between columns is arranged so as to increase by a certain amount compared to the interval between other adjacent columns. It is characterized in that the closest first grating lobe is set smaller than a predetermined increase amount so as to be outside the first null of the subarray antenna.
Also, in an array antenna having a plurality of columns in which the phase centers of a plurality of subarray antennas composed of a plurality of element antennas are arranged, the interval between the phase centers between adjacent subarray antennas in each column is another adjacent subarray antenna. Arranged so as to increase by a certain amount compared to any one of the intervals between the phase centers, and arranged so that the interval between columns increases by a certain amount compared to the interval between other adjacent columns, The increase amount of the interval is set to be smaller than the predetermined increase amount so that the direction of the first grating lobe closest to the main lobe out of the grating lobes is outside the first null of the subarray antenna. And
Further, in an array antenna having a plurality of columns in which the phase centers of a plurality of subarray antennas composed of a plurality of element antennas are arranged, the interval between the phase centers between adjacent subarray antennas of each column is sequentially increased along the arrangement direction. It is arranged so as to increase by a certain amount, and the interval between columns is arranged so as to increase by a certain amount compared to the interval between other adjacent columns. The direction of the nearest first grating lobe is set to a predetermined value so as to coincide with the first null of the subarray antenna.
Also, in an array antenna having a plurality of columns in which the phase centers of a plurality of subarray antennas composed of a plurality of element antennas are arranged, the interval between the phase centers between adjacent subarray antennas in each column is another adjacent subarray antenna. Arranged so as to increase by a certain amount compared to any one of the intervals between the phase centers, and arranged so that the interval between columns increases by a certain amount compared to the interval between other adjacent columns, The increase amount of the interval is characterized by being set to a predetermined value so that the direction of the first grating lobe closest to the main lobe among the grating lobes coincides with the first null of the subarray antenna.
Further, in an array antenna having a plurality of columns in which the phase centers of a plurality of subarray antennas composed of a plurality of element antennas are arranged, the interval between the phase centers between adjacent subarray antennas of each column is sequentially increased along the arrangement direction. It is arranged so as to increase by a certain amount, and the interval between columns is arranged so as to increase by a certain amount compared to the interval between other adjacent columns, and the increase amount of the interval is based on the number of subarray antennas. It is characterized by being larger than a predetermined value to be determined.
Also, in an array antenna having a plurality of columns in which the phase centers of a plurality of subarray antennas composed of a plurality of element antennas are arranged, the interval between the phase centers between adjacent subarray antennas in each column is another adjacent subarray antenna. Arranged so as to increase by a certain amount compared to any one of the intervals between the phase centers, and arranged so that the interval between columns increases by a certain amount compared to the interval between other adjacent columns, The increase amount of the interval is characterized by being larger than a predetermined value determined based on the number of subarray antennas.
Further, in an array antenna having a plurality of columns in which the phase centers of a plurality of subarray antennas composed of a plurality of element antennas are arranged, the interval between the phase centers between adjacent subarray antennas of each column is sequentially increased along the arrangement direction. It is arranged so as to increase by a certain amount, and the interval between columns is arranged so as to increase by a certain amount compared to the interval between other adjacent columns, and the increase amount of the interval is based on the number of subarray antennas. It matches the predetermined value to be determined.
Further, in an array antenna having a plurality of columns in which the phase centers of a plurality of subarray antennas configured by a plurality of element antennas are arranged, the interval between the phase centers between adjacent subarray antennas in each column is another adjacent subarray antenna Arranged so as to increase by a certain amount compared to any one of the intervals between the phase centers, and arranged so that the interval between columns increases by a certain amount compared to the interval between other adjacent columns, The increase amount of the interval is characterized by being equal to a predetermined value determined based on the number of subarray antennas.

  Furthermore, in the array antenna arrangement method according to the present invention, the interval between the phase centers of adjacent subarray antennas of a plurality of subarray antennas composed of a plurality of element antennas is constant compared to the interval between the phase centers of other adjacent subarray antennas. The interval is increased by a predetermined amount so that the direction of the first grating lobe closest to the main lobe out of the grating lobes is outside the first null of the subarray antenna. It is characterized by being set smaller than the increase amount and set larger than a predetermined value determined based on the number of subarray antennas.

  According to the present invention, the grating lobes of the array antenna can be effectively suppressed by arranging the adjacent subarray antennas so as to increase the distance between them by a certain amount.

Embodiment 1 FIG.
1 is a block diagram showing an array antenna according to Embodiment 1 of the present invention. In FIG. 1, the array antenna shown in FIG. 1 includes a plurality of subarray antennas 4 (# s1 to #sM _s ) composed of a plurality of element antennas 1. Sub array antenna 4, for example, the sub-array antennas # s1 is the antenna elements # 1-1~ # 1-M and _e, a phase shifter 2 which is connected to each element antenna, synthesis combining the outputs of a plurality of phase shifters 2 And 3. Other subarray antennas are similarly configured. The array antenna shown in FIG. 1 includes a phase shifter 5 connected to each subarray antenna and a combiner 6 that combines the outputs of the plurality of phase shifters 5. In FIG. 1, the number of sub-array antennas and _{M s,} and each # s1~ # sM _s. Further, the number of elements in the sub-array antenna and _{M e,} the element antennas constituting the sub-array antennas #Sm _s respectively # 1~ # _{M e.}

Further, coordinate axes and angles as shown in FIG. 2 phi, defines a theta, the phase center of the sub-array antennas are arranged on the y-axis, the distance between the phase centers of adjacent sub-array antennas #Sm _s and #sm s _-1 Let d (m _s ).

  FIG. 3 shows an antenna pattern in the case where the antenna constituting the array antenna is not a sub-array antenna but a one-element omni antenna. Here, as shown in the following equation, it is assumed that all the intervals are equal and Da = 50λ (λ: wavelength).

  In FIG. 3, the φ = 0 deg direction is the main lobe. However, when the interval is larger than the wavelength and the array antenna is equally spaced, there is a problem that many grating lobes are generated. If there is a grating lobe, it is not only known from which direction the incoming wave is incident, but it is easy to receive unwanted waves from other than the target direction and is susceptible to interference. This grating lobe occurs because radio waves incident from directions other than the main lobe are in the same phase state as those received in the main lobe direction. Therefore, as the antenna interval is wider, more grating lobes are generated, and the angle difference between the main lobe and the grating lobe is closer.

  Next, FIG. 4 shows an antenna pattern in the case where each antenna of the array antenna is composed of 16-element sub-array antennas of 1/2 · λ equally spaced. The antenna spacing conditions are the same as those shown in FIG. As described above, it is known that the antenna pattern of the array antenna is given by the product of the pattern when each antenna is an omni antenna and the pattern of each sub-array antenna. Here, it can be seen that the envelope of the pattern in FIG. 4 matches the pattern of each subarray antenna.

  Conventionally, focusing on such characteristics, there is a method of controlling the subarray antenna pattern to suppress the grating lobe so that the subarray antenna pattern is null in the direction of the grating lobe, but the antenna interval is large, As shown in FIG. 4, when many grating lobes are generated in the beam of the sub-array antenna and the main lobe and the grating lobe are close to each other, the grating lobe cannot be suppressed.

  In order to suppress the grating lobe, there is a method of randomizing the antenna interval. However, since the grating lobe is uniformly suppressed at a wide incident interval, the effect of suppressing the grating lobe is low. As can be seen from the nature of FIG. 4, only the grating lobes in the beam of the sub-array antenna need be suppressed, and the method of making the intervals random is so inefficient.

  In order to solve the above-described problems, in the present invention, as shown in FIG. 5, the sub-array antenna is arranged such that the interval between the phase centers is increased by a certain amount δ as compared with other adjacent intervals. That is, they are arranged so that the interval between the phase centers between adjacent sub-array antennas increases by a certain amount δ sequentially along the arrangement direction. This can be expressed as follows:

  In FIG. 5, square symbols represent subarrays, and the number of subarray antennas is 16. The number of elements constituting the subarray antenna is 16. Here, FIG. 6 shows an antenna pattern when the antenna constituting the array antenna is an omni antenna. In FIG. 6, the average Da of the antenna interval is 50λ as in FIG. 3. Therefore, the aperture diameter of the entire array antenna is the same. Further, δ in the formula (2) is 6.25% of the average Da of the antenna intervals. FIG. 6 shows that the grating lobe in the direction closer to the main lobe is effectively suppressed compared to FIG. It can also be seen that there are grating lobes that remain unsuppressed. Of these grating lobes, the one closest to the main lobe (0 degree direction) will be referred to as a first grating lobe.

The direction in which the first grating lobe appears is determined by the increment δ in equation (2). That is, each antenna interval differs by an increment δ, so that when the reception phase difference corresponding to the increment antenna interval rotates 2π depending on the incident direction, it becomes the first grating lobe. When the antennas are arranged at equal intervals, grating lobes are generated according to the average Da of the antenna intervals. However, in the method of the present invention, that is, the method in which the antenna interval is increased by a certain amount δ, the grating lobes are increased according to the increment δ. You can control the exit direction. Since the increment δ can be set sufficiently smaller than the average Da of the antenna intervals, the angular difference between the first grating lobe and the main lobe is increased accordingly. The ratio S _{r of the} increment δ to the average Da of the antenna spacing is given by the following equation.

At this time, the angle difference between the first grating lobe and the main lobe in FIG. 6 occurs at a position 1 / _Sr times wider than that in the case of the equidistant arrangement shown in FIG. In Figure 6, since the ratio S _r and 0.0625, it will remain those not suppressed to 16 every other grating lobes in FIG.

  FIG. 7 shows an antenna pattern in a case where each antenna of the array antenna is composed of 16 elements of sub-array antennas of ½ · λ equally spaced. At this time, as in the case of FIG. 4, it can be seen that the antenna pattern of FIG. 6 is a pattern obtained by multiplying the pattern of the subarray antenna. Thus, the grating lobe outside the beam of the sub-array antenna in FIG. 6 is suppressed by the pattern of the sub-array antenna, so that it can be seen that a grating lobe may be generated outside the beam of the sub-array antenna in FIG. Conversely, by generating a grating lobe in part, it is possible to lower the gain of the part close to the main beam other than that, so the gain in the beam of the sub-array antenna can be further increased compared to the array antenna of the random arrangement. Can be lowered. Further, in the random arrangement, it is difficult to predict the direction in which the gain is increased. However, the array antenna according to the present invention has an effect of reliably suppressing the grating lobe near the main lobe.

  Here, the first nulling direction in the sub-array antenna pattern and the first grating lobe when the antenna is an omni antenna in the arrangement according to the expression (2) of the present invention as shown in FIG. It is given by

The antenna arrangement of this invention, or to match the ratio S _r to the value of the right side of equation (4), to be smaller than this, it is possible to outside the pattern of the first grating lobe sub array antenna Therefore, the grating lobe in the subarray beam can be effectively suppressed.

  That is, the amount of increase in the phase center interval between adjacent subarray antennas is set to a predetermined value so that the direction of the first grating lobe closest to the main lobe out of the grating lobes coincides with the first null of the subarray antenna. The grating lobe in the sub-array beam can be effectively suppressed by setting or setting it to be smaller than the predetermined increase amount so as to be outside the first null.

  Here, the case where the antenna constituting the array antenna is a sub-array antenna has been described. However, a directional antenna may be used so that the first grating lobe is generated outside the beam of the directional antenna.

Embodiment 2. FIG.
FIG. 8 shows an antenna arrangement method of the array antenna according to the second embodiment of the present invention. The square symbols represent subarrays as in FIG. 5, and the number of subarray antennas is 16. The number of elements constituting the subarray antenna is 16. The combination of antenna intervals is the same as in FIG. 5, and only the order is different. That is, when the increment δ is 6.25% of the average Da of the antenna interval and the combination of d (1) to d (M _s -2) is obtained and only the order is changed, the phase center between adjacent subarray antennas This is a case where the interval is increased by a certain amount δ compared to any one of the phase center intervals between other adjacent subarray antennas.

  FIG. 9 shows an antenna pattern of the array antenna having the antenna arrangement shown in FIG. The antenna pattern shown in FIG. 9 is the same as that shown in FIG. 7, and the first grating lobe can be set outside the pattern of the subarray antenna. Therefore, the grating lobe in the subarray beam is effectively suppressed. You can see that you can.

  Similarly, by changing the order of the antenna spacing, the outer spacing is larger than the central spacing of the array antenna so that the central spacing becomes dense and the outer spacing becomes sparse. In this case, there is an effect of lowering the gain between the grating lobes.

  Similarly to the first embodiment, the amount of increase in the interval between the phase centers between adjacent subarray antennas is determined so that the direction of the first grating lobe closest to the main lobe among the grating lobes is the first null of the subarray antenna. The grating lobes in the sub-array beam can be effectively suppressed by setting the predetermined values so as to coincide with each other or by setting them to be smaller than the predetermined increase amount so as to be outside the first null.

  Further, as in the first embodiment, the antenna constituting the array antenna may be configured using a directional antenna instead of the sub-array antenna.

Embodiment 3 FIG.
FIG. 10 relates to the third embodiment of the present invention, and shows an antenna pattern when the ratio Sr is 1%. In this example, since the ratio Sr is smaller than the value shown in the equation (4), the grating lobe can be outside the pattern of the subarray antenna, but an unnecessary lobe is generated in the vicinity of the main lobe. I understand that. Thus, it can be seen that even if the ratio Sr is made smaller than the value shown in the equation (4), unnecessary lobes may occur. Therefore, consider the shift rate that minimizes the first lobe in the equally spaced array shown in FIG. What is necessary is just to design so that the phase rotation by the shift amount δ varies, and the optimum shift rate for minimizing the first lobe is as shown in Equation (5). In order to prevent the grating lobe from entering the main lobe of the sub-array, the ratio Sr needs to be smaller than that in the equation (4), so that the shift rate should be set within the range of the equation (6).

  As described above, the ratio Sr can suppress the grating lobe in the subarray beam most effectively when it is set as shown in Equation (5) that can minimize the lobe near the main lobe. FIG. 11 shows an antenna pattern in the case where the number of subarrays is 16 and the shift rate Sr satisfies 1/15 = 0.0667 that satisfies Equation (5). Compared with FIG. 7 in which the shift rate is different under the same conditions, the lobes close to the main lobe, although the characteristics are close, are effectively suppressed.

  That is, the amount of increase in the interval between the phase centers between adjacent array antennas is greater than a predetermined value determined based on the number of subarray antennas or matches a predetermined value determined based on the number of subarray antennas. By setting so that the grating lobes can be suppressed, the grating lobes in the subarray beam can be suppressed.

  Also, in the third embodiment, similarly to the first embodiment, the antennas constituting the array antenna may be configured using directional antennas instead of sub-array antennas.

Embodiment 4 FIG.
The array antenna of the present invention may be used by multiplying Chebyshev distribution, Taylor distribution, or the like as an excitation distribution, which is usually used for the purpose of lowering side lobes throughout the antenna. By multiplying the array function by such a distribution function, the gain between the grating lobes can be lowered in addition to the effect of the first embodiment.

Embodiment 5 FIG.
So far, the one-dimensional array of sub-array antennas has been described. However, for example, the antenna spacing may be as shown in Equation (2) in each axial direction in the two-dimensional plane. In this case, not only the angle φ direction on the coordinate axis shown in FIG. 2 but also the grating lobe in the angle θ direction can be suppressed.

  For example, when the antenna interval in the z-axis direction can be arranged sufficiently small, or when the coverage in the angle θ direction is small, as shown in FIG. The arrangement shown in FIG. The respective rows (y direction) may be arranged in the same arrangement, and as shown in FIG. 12, the combinations of antenna intervals are the same, but they may be arranged in a different order. In this case, no grating lobe is generated in the angle θ direction, and the grating lobe in the beam of the subarray antenna can be effectively suppressed in the angle φ direction as in the first embodiment.

  It is necessary to increase the antenna interval in the z-axis direction, and when the subarray antennas are arranged two-dimensionally, as shown in FIG. 13, not only the y-axis direction but also the z-axis direction is expressed by the equation (2). By determining the antenna interval, the grating lobes in the beam of the subarray antenna can be effectively suppressed even in the angle θ direction. At this time, the antenna arrangement method for the y-axis and the z-axis may be the same, or the antenna interval may be changed to set different antenna arrangements.

  As described above, the array antenna of the present invention can be applied to a two-dimensional arrangement as in the fifth embodiment, and the grating lobes in the sub-array antenna beam can be effectively suppressed.

  Also, in the fifth embodiment, similarly to the first embodiment, the antenna constituting the array antenna may be configured using a directional antenna instead of the sub-array antenna.

Embodiment 6 FIG.
FIG. 14 is a block diagram of an array antenna according to Embodiment 6 of the present invention. In the sixth embodiment shown in FIG. 14, the same parts as those in the first embodiment shown in FIG. The sixth embodiment shown in FIG. 14 uses only a delay control device 7 that can control the delay time variably according to the beam forming direction, instead of the phase shifter 5 of the first embodiment shown in FIG. Different. By arranging the phase centers of the subarray antennas constituting the array antenna in the same manner as in the first embodiment, it is possible to effectively suppress grating lobes in the beam of the subarray antenna.

  In addition, the conventional phase control array antenna has a problem that when applied to a pulsed radar or a distributed array system with a very wide subarray interval, the received waves cannot be combined by the number of antennas, resulting in a decrease in gain. In the sixth embodiment, since the beam is formed by the delay control device 7, there is an advantage that it can cope with a very short pulse wave and can effectively form a beam even when the sub-array antenna interval is wide. By applying such an array antenna having the delay control device 7 and the antenna arrangement according to the equation (2) to a pulse radar of a short pulse wave, it is possible to effectively form a beam and to suppress a wide-angle side lobe. is there.

  FIG. 15 shows an antenna pattern when the array antenna of the sixth embodiment is applied to a pulse radar. A beam can be effectively formed, and a wide-angle side lobe is the same as that of the first embodiment. It turns out that it has fallen compared with shown FIG.

  Also, in the sixth embodiment, similarly to the first embodiment, the antenna constituting the array antenna may be configured using a directional antenna instead of the sub-array antenna.

It is a block diagram which shows the array antenna which concerns on Embodiment 1 of this invention. It is explanatory drawing of arrangement | positioning of the subarray antenna which concerns on Embodiment 1 of this invention. It is a figure which shows an antenna pattern in case the antenna which comprises an array antenna is not a subarray antenna but an omni antenna of 1 element. It is a figure which shows an antenna pattern in case each antenna of an array antenna is comprised with the subarray antenna of 1/2 element of λ which is 16 elements. It is explanatory drawing arrange | positioned so that the space | interval of the phase center of a subarray antenna may increase only a fixed quantity (delta) compared with the other space | interval which adjoins. It is a figure which shows an antenna pattern in case the antenna which comprises an array antenna is an omni antenna. It is a figure which shows an antenna pattern at the time of each antenna of an array antenna being comprised by the subarray antenna of a 1/2 * lambda equal interval of 16 elements. It is a figure which shows the arrangement | sequence method of the antenna of the array antenna which concerns on Embodiment 2 of this invention. It is a figure which shows the antenna pattern of the array antenna by the antenna arrangement | positioning shown in FIG. It is a figure which concerns on Embodiment 3 of this invention, and shows an antenna pattern when ratio Sr is 1%. It is a figure which concerns on Embodiment 3 of this invention, and shows an antenna pattern when ratio Sr is 1/15. An antenna arrangement method for an array antenna according to Embodiment 5 of the present invention will be described. When the subarray antennas are two-dimensionally arranged, the z-axis direction is equally spaced, and only the y-direction is expressed by Equation (2). FIG. An array arrangement method for array antennas according to Embodiment 5 of the present invention will be described. When the subarray antennas are two-dimensionally arranged, not only the y-axis direction but also the z-axis direction is shown in the expression (2). FIG. It is a block diagram of the array antenna which concerns on Embodiment 6 of this invention. It is a figure which shows the antenna pattern at the time of applying the array antenna which concerns on Embodiment 6 of this invention to pulse radar.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Element antenna which comprises subarray antenna, 2 phase shifter, 3 combiner, 4 subarray antenna, 5 phase shifter, 6 combiner, 7 delay control apparatus.

Claims (20)

Provided with a plurality of subarray antennas composed of a plurality of element antennas, and arranged so that the interval between the phase centers of adjacent subarray antennas sequentially increases by a certain amount along the arrangement direction ,
The increase amount of the interval is set to be smaller than the predetermined increase amount so that the direction of the first grating lobe closest to the main lobe out of the grating lobes is outside the first null of the subarray antenna. Characteristic array antenna. With multiple subarray antennas composed of multiple element antennas, the phase center spacing between adjacent subarray antennas increases by a fixed amount compared to any one of the phase center spacings between other adjacent subarray antennas arranged so as to be,
The increase amount of the interval is set to be smaller than the predetermined increase amount so that the direction of the first grating lobe closest to the main lobe out of the grating lobes is outside the first null of the subarray antenna. Characteristic array antenna. The array antenna according to claim 2,
The array antenna is characterized in that the outer spacing is larger than the spacing of the center portion of the array antenna. Provided with a plurality of subarray antennas composed of a plurality of element antennas, and arranged so that the interval between the phase centers of adjacent subarray antennas sequentially increases by a certain amount along the arrangement direction,
The amount of increase in the interval is set to a predetermined value so that the direction of the first grating lobe closest to the main lobe out of the grating lobes coincides with the first null of the sub-array antenna. . With multiple subarray antennas composed of multiple element antennas, the phase center spacing between adjacent subarray antennas increases by a fixed amount compared to any one of the phase center spacings between other adjacent subarray antennas Arranged to
The amount of increase in the interval is set to a predetermined value so that the direction of the first grating lobe closest to the main lobe among the grating lobes coincides with the first null of the subarray antenna.
An array antenna characterized by that. The array antenna according to any one of claims 1 to 5 ,
The array antenna is characterized in that the increase amount of the interval is larger than a predetermined value determined based on the number of sub-array antennas. The array antenna according to any one of claims 1 to 5 ,
The array antenna is characterized in that the increase amount of the interval coincides with a predetermined value determined based on the number of subarray antennas. The array antenna according to claim 7, wherein
When the number of sub-array antennas is Ms and the average value of the sub-array intervals is D, the increase amount of the intervals is D / (Ms-1).
An array antenna characterized by that. The array antenna according to any one of claims 1 to 8 ,
An array antenna characterized by providing a predetermined excitation distribution to the array antenna. In an array antenna comprising a plurality of columns in which the phase centers of a plurality of subarray antennas composed of a plurality of element antennas are arranged,
Arranged so that the phase center spacing between adjacent subarray antennas in each row sequentially increases by a certain amount along the arrangement direction,
The spacing between columns is arranged to increase by a certain amount compared to the spacing between other adjacent columns,
The increase amount of the interval is set to be smaller than the predetermined increase amount so that the direction of the first grating lobe closest to the main lobe out of the grating lobes is outside the first null of the subarray antenna. Characteristic array antenna. In an array antenna comprising a plurality of columns in which the phase centers of a plurality of subarray antennas composed of a plurality of element antennas are arranged,
Arranged so that the interval between the phase centers between adjacent subarray antennas in each row increases by a certain amount compared to any one of the phase center intervals between other adjacent subarray antennas,
The spacing between columns is arranged to increase by a certain amount compared to the spacing between other adjacent columns,
The increase amount of the interval is set to be smaller than the predetermined increase amount so that the direction of the first grating lobe closest to the main lobe out of the grating lobes is outside the first null of the subarray antenna. Characteristic array antenna. In an array antenna comprising a plurality of columns in which the phase centers of a plurality of subarray antennas composed of a plurality of element antennas are arranged,
Arranged so that the phase center spacing between adjacent subarray antennas in each row sequentially increases by a certain amount along the arrangement direction,
The spacing between columns is arranged to increase by a certain amount compared to the spacing between other adjacent columns,
The increase amount of the interval is set to a predetermined value so that the direction of the first grating lobe closest to the main lobe among the grating lobes coincides with the first null of the subarray antenna. . In an array antenna comprising a plurality of columns in which the phase centers of a plurality of subarray antennas composed of a plurality of element antennas are arranged,
Arranged so that the interval between the phase centers between adjacent subarray antennas in each row increases by a certain amount compared to any one of the phase center intervals between other adjacent subarray antennas,
The spacing between columns is arranged to increase by a certain amount compared to the spacing between other adjacent columns,
The increase amount of the interval is set to a predetermined value so that the direction of the first grating lobe closest to the main lobe among the grating lobes coincides with the first null of the subarray antenna. . In an array antenna comprising a plurality of columns in which the phase centers of a plurality of subarray antennas composed of a plurality of element antennas are arranged,
Arranged so that the phase center spacing between adjacent subarray antennas in each row sequentially increases by a certain amount along the arrangement direction,
The spacing between columns is arranged to increase by a certain amount compared to the spacing between other adjacent columns,
The array antenna characterized in that the increase amount of the interval is larger than a predetermined value determined based on the number of subarray antennas. In an array antenna comprising a plurality of columns in which the phase centers of a plurality of subarray antennas composed of a plurality of element antennas are arranged,
Arranged so that the interval between the phase centers between adjacent subarray antennas in each row increases by a certain amount compared to any one of the phase center intervals between other adjacent subarray antennas,
The spacing between columns is arranged to increase by a certain amount compared to the spacing between other adjacent columns,
The array antenna characterized in that the increase amount of the interval is larger than a predetermined value determined based on the number of subarray antennas. In an array antenna comprising a plurality of columns in which the phase centers of a plurality of subarray antennas composed of a plurality of element antennas are arranged,
Arranged so that the phase center spacing between adjacent subarray antennas in each row sequentially increases by a certain amount along the arrangement direction,
The spacing between columns is arranged to increase by a certain amount compared to the spacing between other adjacent columns,
The array antenna is characterized in that the increase amount of the interval coincides with a predetermined value determined based on the number of subarray antennas. In an array antenna comprising a plurality of columns in which the phase centers of a plurality of subarray antennas composed of a plurality of element antennas are arranged,
Arranged so that the interval between the phase centers between adjacent subarray antennas in each row increases by a certain amount compared to any one of the phase center intervals between other adjacent subarray antennas,
The spacing between columns is arranged to increase by a certain amount compared to the spacing between other adjacent columns,
The array antenna is characterized in that the increase amount of the interval coincides with a predetermined value determined based on the number of subarray antennas. The array antenna according to any one of claims 1 to 17 ,
An array antenna comprising: a plurality of delay control units that variably control the delay times of the outputs of the plurality of sub-array antennas according to beam forming directions, respectively, and combining and outputting the outputs of the plurality of delay control units. . The array antenna according to any one of claims 1 to 17 ,
An array antenna characterized by using a directional antenna instead of the sub-array antenna. Arranged so that the interval between the phase centers of adjacent subarray antennas of a plurality of subarray antennas composed of a plurality of element antennas increases by a certain amount compared to the interval between the phase centers of other adjacent subarray antennas,
The interval increase amount is set to be smaller than a predetermined increase amount so that the direction of the first grating lobe closest to the main lobe out of the grating lobes is outside the first null of the subarray antenna. An array antenna arrangement method, wherein the array antenna is set to be larger than a predetermined value determined based on the number of antennas.

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