JP2019208127A - Array antenna substrate and communication module - Google Patents

Abstract

To provide an array antenna substrate that is small-sized and has improved antenna characteristics.SOLUTION: An array antenna substrate 100 comprises: an antenna element area 110 in which surface conductors 2 provided on a first surface 11 of a dielectric substrate 1 and having openings 2a for transmitting and receiving signals, a ground conductor 3 having slots 3a with a lengthwise direction in a first direction, and feedline conductors 4 with a lengthwise direction in a second direction, are arranged opposite in this order with dielectric layers 1a held therebetween, and the surface conductors 2 and ground conductor 3 are connected at through conductors 5; and an array unit 120 in which the antenna element areas 110 are arranged in plurality in connection with each other at least in a second direction. The feedline connectors 4 are connected in series between the plurality of antenna element areas 110 in the second direction, and when the free space wave length of the signals is λ, an array pitch Pa2 of the antenna element areas 110 is an odd number multiple of λ/2. An array pitch Ps of the slots 3a is an integral multiple of an effective wavelength of the signals transmitted through the feedline connectors 4.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an array antenna substrate and a communication module that transmit and receive high-frequency signals such as microwaves and millimeter waves.

In recent years, antenna elements that transmit and receive high-frequency signals such as microwaves or millimeter waves have been used in wireless PANs (Personal Area Networks), on-vehicle radars, and the like. As such an antenna element, a dielectric resonator antenna is known. For the purpose of improving gain, an array antenna substrate in which a plurality of such antenna elements are arranged in a plane direction on a single dielectric substrate is known. (For example, see Patent Document 1 and Patent Document 2).

Japanese Patent Laid-Open No. 11-239017 JP 2012-44484 A

  However, in the conventional array antenna substrate, power supply to a plurality of antenna elements is performed by parallel power supply, and the power supply line therefor has many branch points. Such an array antenna substrate is easily increased in size because the gain of the antenna is reduced due to a loss due to branching, and a space for arranging a feeding line with many branches is required.

  However, the array antenna substrate is required to be further miniaturized and further improved in antenna characteristics such as gain and directivity.

An array antenna substrate of the present disclosure is formed by laminating a plurality of dielectric layers, provided on a dielectric substrate having a first surface and a second surface, and on the first surface of the dielectric substrate. A surface conductor having an opening for transmitting or receiving a signal, a ground conductor having a slot whose length direction is the first direction, and a feed line whose length direction is a second direction orthogonal to the first direction Conductors are arranged in this order so as to face each other with the dielectric layer in between, and are provided circumferentially at a predetermined interval along the opening and penetrate the dielectric layer. An antenna element region in which the surface conductor and the ground conductor are electrically connected by a plurality of through conductors, and an array in which a plurality of antenna element regions are in contact with each other in at least the second direction And the power supply Road conductor extends is connected in series with the second direction between a plurality of said antenna element region are arranged in the second direction, when the free space wavelength of the RF signal and lambda _0, the arrangement pitch of the antenna element region is an odd multiple of lambda _0/2, the array pitch of the second direction of the slot is an integer multiple of the effective wavelength of the signal transmitted through said feed line conductor.

  In the communication module according to the present disclosure, the semiconductor element is mounted on the mounting portion of the array antenna substrate having the mounting portion of the semiconductor element on the second surface opposite to the first surface of the dielectric substrate. ing.

According to the array antenna substrate of one aspect of the present disclosure, since the plurality of arranged antenna elements are serially fed, the loss due to branching is small and the gain is high, and the size can be reduced. Also, with an odd multiple of the arrangement pitch of lambda _0/2 antenna element region, the arrangement pitch of the slots is an integer multiple of the effective wavelength, the side lobes are small, it becomes highly directional array antenna. That is, the array antenna substrate is small and has improved antenna characteristics.

  According to the communication module of the present disclosure, compared to a case where a semiconductor element and an array antenna substrate are mounted on an external circuit board to form a communication module, loss is small and high-frequency signal transmission and reception efficiency is improved. A small communication module can be obtained.

An example of an array antenna board | substrate is shown, (a) is a top view, (b) is sectional drawing in the BB line of (a). The other example of an array antenna board | substrate is shown, (a) is a top view, (b) is sectional drawing in the BB line of (a). FIG. 3 is an exploded perspective view of the array antenna substrate shown in FIG. 2. It is a disassembled perspective view which expands and shows the A section of FIG. FIG. 4 shows another example of an array antenna substrate, where (a) is a plan view, (b) is a sectional view taken along line BB in (a), and (c) is taken along line CC in (a). It is sectional drawing. FIG. 4 shows another example of an array antenna substrate, where (a) is a plan view, (b) is a sectional view taken along line BB in (a), and (c) is taken along line CC in (a). It is sectional drawing. FIG. 4 shows another example of an array antenna substrate, where (a) is a plan view, (b) is a sectional view taken along line BB in (a), and (c) is taken along line CC in (a). It is sectional drawing. FIG. 8 is an exploded perspective view of the array antenna substrate shown in FIG. 7. It is a top view which shows another example of an array antenna board | substrate. (A) is an enlarged plan view showing a portion A of FIG. 9, and (b) and (c) are enlarged plan views showing main portions of other examples of the array antenna substrate. (A) And (b) is a top view which shows another example of an array antenna board | substrate. An example of a communication module is shown, (a) is a perspective view from the 1st surface side, (b) is sectional drawing in the BB line of (a), (c) is the 2nd surface side. FIG. It is a disassembled perspective view which decomposes | disassembles and shows a part of array antenna board | substrate in the communication module of FIG. It is a graph which shows the antenna characteristic of a comparative example. 3 is a graph showing antenna characteristics of Example 1. 6 is a graph showing antenna characteristics of Example 2. 6 is a graph showing antenna characteristics of Example 3. 10 is a graph showing antenna characteristics of Example 4. It is a graph which shows the relationship between the gain of Example 5, and the width | variety of a strip | belt-shaped conductor.

The array antenna substrate will be described with reference to the attached drawings. Each drawing has xyz orthogonal coordinates for convenience of explanation, and hereinafter, there may be a case where a positive side in the z direction is set upward and a word such as a top surface is used. In the following description, the distinction between the upper and lower sides is for convenience, and the upper and lower sides when the array antenna substrate is actually used are not limited. FIG. 1 shows an example of an array antenna substrate, FIG. 1 (a) is a plan view, and FIG. 1 (b) is a sectional view taken along line BB in FIG. 1 (a). 2 shows another example of the array antenna substrate, FIG. 2 (a) is a plan view, and FIG. 2 (b) is a cross-sectional view taken along line BB of FIG. 2 (a). 3 is an exploded perspective view of the array antenna substrate shown in FIG. 4 is an exploded perspective view showing a portion A of FIG. 3 in an enlarged manner. FIG. 5 shows another example of the array antenna substrate, FIG. 5 (a) is a plan view, FIG. 5 (b) is a sectional view taken along line BB in FIG. 5 (a), and FIG. ) Is a cross-sectional view taken along the line CC in FIG. FIG. 6 shows another example of the array antenna substrate, FIG. 6 (a) is a plan view, FIG. 6 (b) is a sectional view taken along line BB in FIG. 6 (a), and FIG. ) Is a cross-sectional view taken along the line CC in FIG. FIG. 7 shows another example of the array antenna substrate, FIG. 7 (a) is a plan view, FIG. 7 (b) is a sectional view taken along line BB in FIG. 7 (a), and FIG. It is sectional drawing in the CC line of Fig.7 (a). FIG. 8 is an exploded perspective view of the array antenna substrate shown in FIG. FIG. 9 is a plan view showing another example of the array antenna substrate. FIG. 10A is an enlarged plan view showing part A of FIG. 9, and FIG. 10B and FIG. 10C are enlarged plan views showing main parts of another example of the array antenna substrate. It is. FIG. 11A and FIG. 11B are plan views showing another example of the array antenna substrate. FIG. 12 shows an example of a communication module, FIG. 12 (a) is a perspective view from the first surface side of the array antenna substrate, and FIG. 12 (b) is a cross section taken along line BB in FIG. 12 (a). FIG. 12C is a perspective view from the second surface side of the array antenna substrate. 13 is an exploded perspective view showing a part of the array antenna substrate in the communication module of FIG. 12 in an exploded manner.

  The array antenna substrate 100 is a dielectric substrate 1 having a first surface 11 and a second surface 12 as in the examples shown in FIGS. 1, 2, 5 to 7, 9, and 11 to 13. In addition, a plurality of antenna element regions 110 are arranged. In other words, the array antenna substrate 100 includes an array unit 120 in which a plurality of antenna element regions 110 are arranged. The dielectric substrate 1 is formed by laminating a plurality of dielectric layers 1a as in the example shown in FIG. In the example shown in FIG. 1 to FIG. 3, the dielectric substrate 1 has three dielectric layers 1a. In the example shown in FIGS. 5 to 8, the dielectric substrate 1 has four dielectric layers 1a. In the example shown in FIG. 12, the dielectric substrate 1 has seven dielectric layers 1a.

  The antenna element region 110 is provided on the first surface 11 of the dielectric substrate 1 and transmits or receives high-frequency signals, as in the examples shown in FIGS. 1, 2, 5 to 7, and 12. A surface conductor 2 having an opening 2a, a ground conductor 3 having a slot 3a whose length direction is the first direction, and a feed line conductor 4 whose length direction is a second direction orthogonal to the first direction; And the through conductor 5. The second direction is the electric field direction of the high-frequency signal to be transmitted / received. In each drawing, the first direction is the y direction and the second direction is the x direction. In each antenna element region 110, the surface conductor 2, the ground conductor 3, and the feed line conductor 4 are arranged in this order so as to face each other with the dielectric layer 1a interposed therebetween. The surface conductor 2 and the ground conductor 3 are electrically connected by a plurality of through conductors 5 provided circumferentially along the opening 2a at predetermined intervals and penetrating the dielectric layer 1a. . The distance between the surface conductor 2 and the ground conductor 3 is ¼ (λg / 4) of the effective wavelength (λg) of the signal transmitted within the array antenna substrate 100 and the signal transmitted through the feeder line conductor 4. With such a configuration, a dielectric resonator antenna is configured in the antenna element region 110.

In FIG. 3, FIG. 8, and FIG. 13, the through conductor 5 is omitted for easy viewing. In FIG. 4 showing the A portion of FIG. 3 in an enlarged manner, the through conductor 5 is indicated by a broken line, and both end portions which are connection ends are indicated by black circles. In FIG. 4, only the arrangement of the through conductors 5 in one antenna element region 110 is shown. Further, in the examples shown in FIGS. 1 to 8, 12 and 13, two dielectric layers 1a are interposed between the surface conductor 2 and the ground conductor 3, and the two dielectric layers 1a. An interlayer conductor 5a is provided between these layers. The interlayer conductor 5a is not necessarily required, but when a plurality of dielectric layers 1a are provided between the surface conductor 2 and the ground conductor 3, the interlayer conductor 5a is provided to penetrate each dielectric layer 1a. The connectivity between the through conductors 5 can be improved.

  In the array unit 120, a plurality of antenna element regions 110 are arranged in contact with each other in at least the second direction. The array antenna substrate 100 in the example shown in FIGS. 1 and 2 includes one array unit 120 in which four antenna element regions 110 are arranged only in the second direction (x direction). The array antenna substrate 100 in the example shown in FIGS. 5 to 7 and 11 is an array in which four antenna element regions 110 are arranged in the second direction (x direction) and two in the first direction (y direction). One section 120 is provided. The array antenna substrate 100 of the example shown in FIG. 9 includes one array unit 120 in which four antenna element regions 110 are arranged in the second direction (x direction) and three in the first direction (y direction). ing. In these drawings, one array part 120 is surrounded by a two-dot chain line, and the outer edge of the antenna element region 110 is indicated by a long broken line. The array antenna substrate 100 in the example shown in FIGS. 12 and 13 includes an array unit 102 in which eight antenna element regions 101 are arranged in the second direction (x direction) and two in the first direction (y direction). Two array units 102 are arranged in the first direction.

  In one array unit 120, a plurality of antenna element regions 110 are arranged in contact with each other. Therefore, it appears that a plurality of openings 2 a are provided in one surface conductor 2 on the first surface 11 of the dielectric substrate 1. The feed line conductor 4 in each antenna element region 110 is connected in series between the plurality of antenna element regions 110 arranged in the second direction. For this reason, in the array unit 120, one feed line conductor 4 extending in the second direction is provided for one row formed of the plurality of antenna element regions 110 arranged in the second direction. As described above, since the plurality of antenna element regions 110 arranged in the second direction are serially fed by one linear feed line conductor 4 without branching, there is no loss of feed signal due to branching. The antenna gain is high. Further, since the space for providing the feed line conductor 4 can be small, the array antenna substrate 100 can be reduced in size.

  In the example shown in FIG. 1, the right end (− side in the x direction) of the feed line conductor 4 is a feed end 4 a to which a signal is input (supplied) from the outside, and the outside of the array unit 120 in a plan view. Located on the right side. The end (tip 4b) on the left side (+ side in the x direction) located on the side opposite to the feeding end 4a is located on the left side from the slot 3a of the leftmost antenna element region 110. The distance between the tip 4b and the center in the width direction (second direction) of the slot 3a can be ¼ (λg / 4) of the effective wavelength λg. In this way, the signal transmitted through the feeder line conductor 4 and the reflected signal reflected by the tip 4b cancel each other, so that deterioration of radiation characteristics due to reflection at the tip 4b can be reduced.

The array antenna substrate 100 transmits or receives a high-frequency signal from the opening 2a of each antenna element region 110. When the free space wavelength of this high-frequency signal is λ ₀ , the array pitch in the second direction of the antenna element region 110 ( Pa2 shown in FIGS. 1 and 2) is an odd multiple of lambda _0/2. On the other hand, the arrangement pitch (Ps shown in FIGS. 1 and 2) of the slots 3a in each antenna element region 110 in the second direction is an integral multiple of the effective wavelength (λg) of the signal transmitted through the feeder line conductor 4. Since the arrangement pitch Pa2 antenna element region 110 is an odd multiple of lambda _0/2, the phase difference of the radio wave radiated from the antenna element region 110 adjacent in the second direction becomes 180 °, the second direction The radiated radio waves are canceled and the side lobes of the entire array antenna are reduced. Since the arrangement pitch Ps of the slots 3a is an integral multiple of the effective wavelength (λg), there is no phase difference between signals transmitted from the feeder line conductor 4 to each slot 3a. In other words, the signal has the maximum amplitude at the same timing in each slot 3a, and the resonance timing in each slot 3a is aligned, so that the array antenna has a small side lobe and high directivity. For this reason, the array antenna substrate 100 is small and has improved antenna characteristics. Here, the arrangement pitch Ps of the slots 3a is an integer multiple of the effective wavelength λg, for example, not strictly 1.0 times, but strictly integer multiples such as 0.9 times to 1.1 times. It has a width of 10%. For example, when the effective wavelength λg is 1.84 mm, the arrangement pitch Ps of the slots 3a can be set to 1.66 mm to 2.02 mm. Since the amplitude is not large with respect to the wavelength of the signal and the waveform is not steep, if the width is within this range, the amplitude is the same as the maximum amplitude in each slot 3a, the side lobe is small, and the directivity is high. It becomes an array antenna.

In the example shown in FIGS. 1 and 2, the arrangement pitch Ps of the slots 3a is smaller than the arrangement pitch Pa2 of the antenna element region 110. As described above, the distance between the surface conductor 2 and the ground conductor 3 is ¼ (λg1 / 4) of the effective wavelength λg1 between them. In order to make the array antenna substrate 100 thin, the effective wavelength λg1 may be reduced. The effective wavelength λg1 decreases as the relative dielectric constant of the dielectric layer 1a increases. At this time, the dielectric constant of the dielectric layer 1a around the feed line conductor 4 also increases, and the effective wavelength λg of the signal transmitted through the feed line conductor 4 also decreases. Further, and it may be any odd number of times the arrangement pitch Pa2 is lambda _0/2 of the antenna element region 110, but the arrangement pitch Pa2 antenna element region 110 for compactness it is better is smaller, the antenna element region 110 the arrangement pitch Pa2 λ _0/2 may (λ _0/2 of 1-fold) to. Therefore, when the feed line conductor 4 is a microstrip line as in the example shown in FIGS. 1 and 2, if the relative dielectric constant of the dielectric layer 1a is approximately 5 or more, the arrangement pitch Ps of the slots 3a is the antenna pitch. It becomes smaller than the arrangement pitch Pa2 of the element regions 110. Since the arrangement pitch Ps of the slots 3a and the arrangement pitch Pa2 of the antenna element regions 110 are different, the positions of the slots 3a in each antenna element region 110 are different from each other.

  In the example shown in FIG. 1, the leftmost of the four antenna element regions 110 arranged in the second direction, in other words, the slot in the antenna element region 110 (111) on the tip 4b side of the feed line conductor 4 is a slot. 3a is located at the center of the antenna element region 110 in the second direction. On the other hand, in the example shown in FIG. 2, the antenna at the rightmost position among the four antenna element regions 110 arranged in the second direction, in other words, the antenna closest to the feed end 4 a of the feed line conductor 4. In the element region 110 (111), the slot 3a is located at the center of the antenna element region 110 in the second direction. Here, of the four antenna element regions 110 arranged in the second direction, the one in which the slot 3a is located at the center of the second direction in the antenna element region 110 is referred to as a first antenna element region 111. .

  When the slot 3a is in a position that overlaps the center of the antenna element region 110, in other words, the center of the opening 2a in a plan view, it is perpendicular to the first surface 11 of the dielectric substrate 1 (zenith direction, z direction in the drawing) ) Is likely to be radiated, in other words, the directivity is high. Therefore, the slot 3 a is usually arranged at the center of the antenna element region 110. However, if the arrangement pitch Ps of the slots 3a and the arrangement pitch Pa2 of the antenna element regions 110 are different, the first antenna in which only one of the plurality of antenna element regions 110 arranged in a line is located at the center of the slot 3a. The element region 111 cannot be formed.

Further, as described above, when a plurality of antenna element regions 110 are fed by the linear feeding line conductor 4, there is no branching compared to the parallel feeding, so that an array antenna having a small loss and a high gain can be obtained as a whole. it can. However, the distance from the feed end 4a of the feed line conductor 4 to each antenna element region 110 (slot 3a thereof) is different, and the longer the distance, the greater the loss. On the contrary, the closer to the feed end 4a, the smaller the loss, so that the antenna element region 110 closer to the feed end 4a has a larger gain. When the first antenna element region 111 having high directivity is arranged at the position closest to the feeding end 4a, the gain of the first antenna element region 111 having high directivity becomes the largest, so that the directivity of the entire array becomes high. In other words, in order to achieve higher directivity, a plurality of antenna element regions 110 arranged in the second direction are arranged such that the slot 3a is located at the center of the antenna element region 110 in the second direction. One antenna element region 111 may be included, and the first antenna element region 111 may be the array antenna substrate 100 located closest to the feed end 4a of the feed line conductor 4 in the second direction.

  The array antenna substrate 100 in the example shown in FIGS. 5 to 7 includes one array unit 120 in which four antenna element regions 110 are arranged in the second direction and two (two rows) in the first direction. Have one. A total of two feed line conductors 4 are arranged, one for each of two groups of four antenna element regions 110 arranged in the second direction. In the array antenna substrate 100 of the example shown in FIG. 5, the two first antenna element regions 111 are both arranged at the positions farthest from the feeding end 4a. On the other hand, in the array antenna substrate 100 of the example shown in FIG. 6, the two first antenna element regions 111 are both arranged at the position closest to the feeding end 4a. In the example of the array antenna substrate 100 shown in FIG. 7, one of the two first antenna element regions 111 is disposed at a position closest to the feeding end 4a, and the other is disposed at a position farthest from the feeding end 4a. Has been.

  A second direction in which both the first antenna element region 111 and the first antenna element region 111 are arranged at the position farthest from the feeding end 4a and the first antenna element region 111 is arranged at the position closest to the feeding end 4a. The radiation characteristic has directivity in (x direction), and the directivity in the second direction (x direction) is opposite to each other. In addition, as described above, when the first antenna element region 111 is disposed at the position farthest from the feeding end 4a, the first antenna element region 111 is disposed at the position closest to the feeding end 4a. In this case, the side lobe is reduced and the directivity is increased. This is the same even when a plurality of antenna element regions 110 are provided in the first direction in one array unit 120.

  However, when a plurality of rows of antenna element regions 110 are arranged in the first direction, radiation in the second direction (x direction), that is, side lobes in the 90 degree direction with respect to the vertical direction (zenith direction) to be radiated also increases. May end up. When the first antenna element region 111 is disposed at a position closest to the feeding end 4a, radiation toward the opposite side (+ side in the x direction) from the feeding end 4a increases, and the first antenna element region 111 feeds. When it is arranged at the position farthest from the end 4a, the radiation toward the feeding end 4a side (the negative side in the x direction) increases. When radiation in the second direction (x direction) increases, for example, when the array antenna substrate 100 is used for a beam forming radar, unnecessary radiation may be easily detected by this radiation. There is. On the other hand, as in the example shown in FIG. 7, the first antenna element region 111 is closest to the feed end 4a and the row where the first antenna element region 111 is located farthest from the feed end 4a. If the columns arranged at positions are provided, the radiation in the second direction is small as a whole because the directivities in the second direction opposite to each other are adjacent to each other.

  In this way, in order to increase the overall directivity and suppress radiation in the second direction, one array unit 120 is a plurality of rows in which a plurality of antenna element regions 110 are arranged in contact with each other in the first direction. A first row 121 having a first antenna element region 111 closest to the feed end 4a of the feed line conductor 4 and a first antenna element region 111 having a slot 3a located at the center of the antenna element region 1110 in the second direction; The array antenna substrate 100 in which the first antenna element region 111 and the second row 122 farthest from the feeding end 4a of the feeding line conductor 4 are arranged adjacent to each other in the first direction can be used.

In the example shown in FIGS. 7 and 8, the array unit 120 is arranged in two rows in the first direction, and the first antenna element region 111 is closest to the feed end 4 a of the feed line conductor 4. In the second row 122, the first antenna element region 111 is farthest from the feed end 4a of the feed line conductor 4.
And one each. On the other hand, in the example shown in FIG. 9, the array units 120 are arranged in three rows in the first direction, and the two first antenna element regions 111 are the first closest to the feed end 4 a of the feed line conductor 4. In this row 121, one first antenna element region 111 is arranged with the second row 122 farthest from the feed end 4a of the feed line conductor 4 being sandwiched. In other words, the first column 121 and the second column 122 are alternately arranged in the first direction. On the contrary, two second columns 122 can be arranged with one first column 121 interposed therebetween, but the more first columns, the higher the directivity.

Further, if the array 120 has a plurality of antenna element regions 110 in the first direction are arranged, and odd multiples of the antenna element region sequences pitch Pa1 of the first direction 110 also lambda _0/2 can do. In this way, the phase difference between the radio waves radiated from the antenna element regions 110 adjacent to each other in the first direction becomes 180 °, the radio waves radiated in the first direction are canceled, and the side lobes are reduced. At this time, in order to reduce the size of the array antenna substrate 100, the arrangement pitch Pa1 in the first direction of the antenna element region 110 is preferably smaller, and the arrangement pitch Pa1 in the first direction of the antenna element region 110 is set to λ _0. / 2 may (λ _0/2 of 1-fold) to.

The gain can be increased as the size of the opening 2a of the surface conductor 2 is increased. For example, if the array antenna substrate 100 and the antenna element region first direction arrangement pitch Pa1 and the arrangement pitch Pa2 the lambda _0/2 of the second direction 110 in order to reduce the size of the aperture 2a of the surface conductor 2 side the length of the lambda _0/2 less than in lambda _0/2 as close as possible to the dimensions of the square.

  FIG. 10A to FIG. 10C show an example in which the shape of the opening 2a of the surface conductor 2 is a square shape. FIGS. 10B and 10C are square. The through conductor 5 in the example shown in FIGS. 10B and 10C is located outside the opening 2a of the surface conductor 2 in plan view and is connected to the surface conductor 2 outside the opening 2a. . On the other hand, in the example shown in FIG. 10A, half of the through conductor 5 is located in the opening 2a and half is located outside the opening 2a in plan view. In order to improve the connectivity between the through conductor 5 and the surface conductor 2, the shape of the opening 2a is such that a part of a square side protrudes inward. The shape of the opening 2a being square means that it includes such a shape as well as a square.

  It is also possible to arrange the through conductors 5 in a line on the boundary (long broken line in the figure) between two adjacent antenna element regions 110 to form a common through conductor 5 between the two adjacent antenna element regions 110. . On the other hand, as in the example shown in FIGS. 10A to 10C, the penetrating conductor 5 is formed at the boundary portion between two adjacent antenna element regions 110, that is, between two adjacent openings 2 a. These are provided along the respective openings 2a of the adjacent antenna element regions 110, and can be arranged in two rows in plan perspective. By providing the through conductors 5 in two rows along the respective openings 2a of the adjacent antenna element regions 110, the isolation between the two adjacent antenna element regions 110 can be improved, and the operation performance of the array antenna can be improved. Can do.

  In the example shown in FIGS. 10A and 10B, the through conductors 5 arranged in two rows have the same position in the first direction. In other words, the through conductors 5 arranged in two rows are positioned so as to overlap each other when viewed from the side in the second direction. On the other hand, in the example shown in FIG. 10C, the through conductors 5 arranged in two rows have different positions in the second direction and overlap each other when viewed from the side in the first direction. In position. In other words, the through conductors 5 can be arranged in a staggered manner in a plan view at the boundary between two adjacent antenna element regions 110.

  In order to increase the opening 2a as much as possible in order to increase the gain, the interval between the two rows of through conductors 5 arranged between the openings 2a of the adjacent antenna element regions 110 is reduced. When the distance is reduced, the isolation between adjacent antenna element regions may be deteriorated, or cracks may be generated between the through conductors 5 of the dielectric substrate. Since the interval can be increased by using a staggered arrangement, the isolation between adjacent antenna element regions can be maintained, and the possibility of occurrence of cracks between the through conductors 5 of the dielectric substrate can be reduced.

  The opening 2a is defined by a strip-like conductor 21 extending in the second direction and a connection conductor 22 extending in the first direction. More specifically, the pair of strip-shaped conductors 21 positioned with the opening 2a sandwiched in the first direction, and the adjacent ends of the pair of strip-shaped conductors 21 positioned with the aperture 2a sandwiched in the second direction. An opening 2a is defined by a pair of connecting conductors 22 that connect the two.

  The width (length in the second direction) of the portion (connection conductor 22 shown in FIG. 11) sandwiched between the openings 2a in the second direction in the surface conductor 2 is the arrangement of the antenna element regions 110 in the second direction. This is the length obtained by subtracting the length of the opening 2a in the second direction from the pitch Pa2. Further, the width (length in the first direction) of the portion (the strip-shaped conductor 21 shown in FIG. 11) sandwiched between the openings 2a in the first direction in the surface conductor 2 is also the same. This is a length obtained by subtracting the length in the first direction of the opening 2a from the arrangement pitch Pa1 in the first direction. The portion sandwiched between the openings 2a in the surface conductor 2 needs to be reduced in order to enlarge the opening 2a, but the strip-like conductors 21 located at the outer edge portions of the surface conductor 2, that is, both ends in the first direction. And the width | variety can be enlarged about the connection conductor 22 located in the both ends of a 2nd direction. FIG. 11A and FIG. 11B are examples in which the width of the strip-shaped conductor 21 located at both ends in the first direction is increased. In the example shown in FIG. 11A, the antenna element regions 110 are arranged in two rows in the first direction, and in the example shown in FIG. 11B, there are only one row in the first direction. In the example shown in FIG. 11B, there is no strip-shaped conductor 21 sandwiched between the openings 2a in the first direction, and only the strip-shaped conductors 21 at both ends are provided.

Of the strip-shaped conductors 21 located across the opening 2a in the first direction, the width in the first direction of the strip-shaped conductors 21 positioned at both ends in the first direction in the array unit 120 is the free space wavelength of the high-frequency signal. may be an array antenna substrate 100 is λ ₀ / 4~λ _0/2 when the lambda _0. Side the yz plane by the first direction by a first width w of the band-shaped conductor 21 is as large as lambda _0/4 or (y-direction) and upper (z-direction) located at both ends in the first direction it is possible to lower the lobes, it is possible to suppress a decrease of the gain by a first width w of the band-shaped conductor 21 is lambda _0/2 or less.

  Further, the width in the second direction of the connection conductors 22 located at both ends in the second direction in the array unit 102 can be set to λ / 8 or less. A decrease in gain and an increase in side lobes due to the wide width of the connection conductor 22 can be suppressed.

  As in the example shown in FIG. 13, the feed wiring conductor 8 is connected to the feed line conductor 4 in each antenna element region 110. When each antenna element region 110 transmits radio waves, for example, a high-frequency signal output from a high-frequency semiconductor element is transmitted to each feed line conductor 4 by the feed wiring conductor 8 and is electromagnetically coupled to the feed line conductor 4. Through the slot 3 a of the ground conductor 3, the resonance region surrounded by the surface conductor 2, the through conductor 5 and the ground conductor 3 is transmitted and radiated from the opening 2 a of the surface conductor 2. When receiving radio waves, the radio waves are received through the openings 2 a of the surface conductor 2, and the high frequency signal reaches the feed line conductor 4 in the reverse flow to that in the case of transmission.

The array antenna is intended to increase the gain by arranging a plurality of antennas having the same structure and size close to each other. It is desired that the high-frequency signals transmitted and received in the plurality of antenna element regions 110 have small variations in characteristics. For this purpose, the transmission variation of the feed wiring conductor 8 that transmits a high-frequency signal to the feed line conductor 4 in each antenna element region 110 needs to be small. This transmission variation becomes small if the variation in the transmission loss of the feeder wiring conductor 8 to the feeder line conductor 4 in each antenna element region 110 is small. Variations in transmission loss can be reduced by equalizing the length and shape of the transmission line.

  The array antenna substrate 100 as described above includes, for example, an electrode 7 provided on the second surface 12 opposite to the first surface 11 of the dielectric substrate 1 as in the example shown in FIG. This is connected to an external circuit through this electrode. The electrode 7 is electrically connected to the ground conductor 3 and the feed line conductor 4 via a wiring conductor provided on the dielectric substrate 1. As a result, the high-frequency semiconductor element mounted on the external circuit, for example, the external circuit board, and the feeder line conductor 4 in the antenna element region 110 are electrically connected to transmit a high-frequency signal.

  An array antenna substrate having a mounting portion 130 of a semiconductor element 200 on the second surface 12 opposite to the first surface 11 of the dielectric substrate 1 like the array antenna substrate 100 of the example shown in FIG. 100. The communication module 300 can be formed by mounting a semiconductor element on the mounting portion 130 of the array antenna substrate 100. Compared with the case where the semiconductor element 200 and the array antenna substrate are mounted on the external circuit board to form a communication module, the wiring length between the semiconductor element 200 and the antenna element region 110 (feed line conductor thereof) is shortened. Loss is small, and high-frequency signal transmission and reception are efficient. Further, since the array antenna substrate 100 and the semiconductor element 200 are arranged so as to overlap each other, a small communication module 300 is obtained. Since the array antenna substrate 100 of the communication module 300 in the example shown in FIG. 12 includes two array units 120, for example, one array unit 120 is used for transmission and the other one array unit 120 is used for reception. be able to. Such a communication module 300 can be used, for example, in an in-vehicle radar device for inter-vehicle measurement.

  The mounting portion 130 in the array antenna substrate 100 of the example shown in FIG. 12 is a concave portion provided in the center portion of the second surface 12 of the dielectric substrate 1, and a connection pad (not shown) provided on the bottom surface of the concave portion. And an electrode (not shown) of the semiconductor element 200 are electrically connected. There is an electrode 7 around the recess in the second surface 12 of the dielectric substrate 1. The electrode 7 is electrically connected to the ground conductor 3 and the connection pad via a wiring conductor (not shown) provided on the dielectric substrate 1. The connection pad is also connected to the feeder line conductor 4 via a wiring conductor provided inside the dielectric substrate 1. FIG. 13, which is an exploded perspective view showing the configuration of the antenna element region 110 in the example shown in FIG. 12, shows an example in which the connection pad and the feed line conductor 4 are connected via the feed wiring conductor 8. One power supply wiring conductor 8 is arranged for one array unit 120. In the example shown in FIG. 13, the wiring conductor connected to the connection pad and the feeder wiring conductor 8 are connected by a through conductor. The through conductor is connected to the feed point of the feed wiring conductor 8, and in order to reduce the variation in transmission loss from the feed point to each feed line conductor 4, one array section is formed from the feed point of the feed wiring conductor 8. Each of the two feed line conductors 120 is equal in length.

  In the array antenna substrate 100 of the example shown in FIGS. 1 to 3 and 4 to 8, the feed line conductor 4 is a microstrip line, but may be any as long as it can transmit a high-frequency signal. In the example of the array antenna substrate 100 shown in FIG. 13, the feed line conductor 4 is a strip line configured with the second ground conductor 6 opposed via the dielectric layer 1 a. In the case of a microstrip line, the feed line conductor 4 is provided on the second surface 12 of the dielectric substrate 1. However, in the case of a strip line, the feed line conductor 4 is disposed in the dielectric substrate 1, and the feed line conductor 4. A wiring conductor can be formed from the second surface 12 to the second surface 12, and the array antenna substrate 100 can be easily formed as shown in FIG. 12.

  In the array antenna substrate 100 described above, only the through conductor 5 that connects the surface conductor 2 and the ground conductor 3 is provided. For example, in the array antenna substrate 100 of the example shown in FIGS. And a through conductor that electrically connects the second ground conductor 6 and the ground conductor 3 may be provided. This penetration conductor becomes an electromagnetic field shield, and the isolation characteristic of the feed line conductor 4 is improved, and the transmission characteristic of the high frequency signal by the feed line conductor 4 is improved. Further, the through conductor may be connected to the ground conductor 3 so as to surround the slot 3a. In this case, the signal fed to the slot 3a is efficiently transmitted to the surface conductor 2.

  The dielectric substrate 1 may have a flat plate shape having no recess, but if the recess has the recess, the semiconductor element 200 protrudes from the array antenna substrate 100 (the second surface 12 of the dielectric substrate 1). Therefore, it is easy to protect the semiconductor element, and the connection between the electrode 7 and the external circuit board is easy. When the mounting portion 130 in the array antenna substrate 100 is a recess provided on the second surface 12 of the dielectric substrate 1, the semiconductor element 200 can be sealed by filling the recess with a sealing resin.

  The semiconductor element 200 includes a circuit for performing signal processing, amplification, transmission / reception switching, phase switching, frequency switching, and the like, and signals transmitted and received by the array antenna substrate 100 are controlled by this circuit.

  The dielectric substrate 1 is a basic structural part of the array antenna substrate 100, and ensures mechanical strength as the array antenna substrate 100 and between conductors such as between the plurality of surface conductors 2 and the ground conductor 3. It has functions such as ensuring insulation. The dielectric substrate 1 is, for example, a square shape such as a square shape or a rectangular shape when viewed from above (in plan view), and has a flat plate shape. The dimensions of the dielectric substrate 1 can be set such that, for example, the length of one side of the quadrangle is 3 mm to 100 mm and the thickness is 0.3 mm to 3 mm.

  The dielectric substrate 1 includes a plurality of dielectric layers 1a made of a dielectric material made of a ceramic material such as an aluminum oxide sintered body, a glass ceramic sintered body, a mullite sintered body, or an aluminum nitride sintered body. It is formed by stacking. The number of the dielectric layers 1a is not limited to the above-described example.

If the dielectric substrate 1 is made of, for example, a glass ceramic sintered body, it can be manufactured as follows. First, a raw material powder mainly composed of powders such as silicon oxide, boron oxide and aluminum oxide serving as a glass component are kneaded with an organic solvent and a binder to form a slurry, and this slurry is subjected to a doctor blade method or A ceramic green sheet (hereinafter also referred to as a green sheet) to be a dielectric layer 1a of the dielectric substrate 1 is formed by forming into a sheet by a molding method such as a lip coater method. Next, a plurality of green sheets are laminated to produce a laminate. Then, the dielectric substrate 1 can be manufactured by firing this laminated body at a temperature of about 900 to 1000 ° C.

  The array antenna substrate 100 including the dielectric substrate 1 can also be manufactured as a multi-piece substrate in which a plurality of substrate regions to be the array antenna substrate 100 are arranged on a mother substrate. A plurality of array antenna substrates 100 can be more efficiently manufactured by dividing a mother substrate including a plurality of substrate regions into each substrate region. In this case, a dividing groove may be provided along the boundary of the substrate region in the mother substrate.

The wiring conductor including the surface conductor 2, the ground conductor 3, the feed line conductor 4, the interlayer conductor 5a, the second ground conductor 6, the electrode 7 and the feed wiring conductor 8 is, for example, tungsten, molybdenum, manganese,
Metal materials such as copper, silver, palladium, gold, platinum, nickel or cobalt, or metal materials of alloys containing these metals are mainly included as conductor materials. Such a metal material is provided on the surface of the dielectric substrate 1 as a metal layer such as a metallized layer or a plating layer. This metal layer may be a single layer or a plurality of layers. Further, such a metal material is provided inside the dielectric substrate 1 as a metal layer of the metallized layer.

  For example, when the wiring conductor is a copper metallized layer, a metal paste prepared by mixing copper powder with an organic solvent and an organic binder is screen-printed at a predetermined position of the green sheet to be the dielectric layer 1a. It can form by the method of printing with this method, and baking with a green sheet. Further, the through conductor 5 can be formed by providing a through hole at a predetermined position of the green sheet prior to the printing of the metal paste and filling the through hole with the same metal paste as described above. .

  The exposed surface of the surface conductor 2 and the electrode 7 provided on the surface of the dielectric substrate 1 is further coated with a plating layer such as nickel and gold by a plating method such as an electrolytic plating method or an electroless plating method. Also good. In this case, as described above, when the array antenna substrate 100 is manufactured in the form of the multi-piece substrate, if the wiring conductors of the plurality of substrate regions are electrically connected to each other, the wiring of the plurality of array antenna substrates 100 is performed. It is also possible to deposit the plating layer all together on the conductor.

  The size of the ground conductor 3 can be appropriately set according to the antenna characteristics required for the array antenna substrate 100 and by the relative dielectric constant and thickness of the dielectric layer 1a. The same applies to the dimensions of the slot 3 a and the feed line conductor 4 provided in the ground conductor 3. The configuration and dimensions of each antenna element region 110 in one array section 120 are the same, but the dimensions and the like of each section may be different between different array sections 120, and the antenna characteristics may be different.

  The space between the array units 120 may be a space that can ensure the required isolation depending on the characteristics of the antenna elements, but may be, for example, 1 mm to 10 mm.

  The antenna characteristics of the array antenna substrate 100 of this embodiment were evaluated based on the radiation pattern obtained by simulation. The model of the array antenna substrate 100 used for the simulation is as follows.

  The frequency of the high frequency signal transmitted or received from the opening 2a of the surface conductor 2 was 79 GHz used for millimeter wave radar. The free space wavelength λ0 at 79 GHz is 4 mm. The arrangement pitch Pa (Pa2) in the second direction of the antenna element region 110 was 2 mm (λ0 / 2). When the antenna element regions 110 are also arranged in the first direction, the arrangement pitch Pa1 in the first direction is also 2 mm (λ0 / 2). The opening 2a of the surface conductor 2 was a square with a side length of 1.8 mm. Therefore, the width of the portion between the openings 2a of the surface conductor 2 is 0.2 mm. That is, the width of the strip conductor 21 and the connection conductor 22 of the surface conductor 2 is 0.2 mm.

The dielectric substrate 1 is assumed to be a low-temperature fired ceramic such as so-called glass ceramics as a material of the dielectric layer 1a, and has a relative dielectric constant of 5.8. The distance between the surface conductor 2 and the ground conductor 3 is 0.4 mm, and the distance between the ground conductor 3 and the feed line conductor 4 is 0.1 mm. The feed line conductor 4 is a microstrip line provided on the second surface 12 of the dielectric substrate 1 and having a width of 0.145 mm and a thickness of 0.1 mm. At this time, the effective wavelength λg of the signal transmitted through the feeder line conductor 4 is 1.84 mm. Therefore, it can be said that if the length is 1.66 mm to 2.02 mm, the length is one time the effective wavelength λg.

  The array antenna substrate 100 has one array portion 120, and simulations are performed on models having different arrangements of antenna element regions 110 and slots 3a in the array portion 120, and radiation patterns as shown in FIGS. Got. 14 to 18, the 0 ° direction indicates the zenith direction, and the ± 90 ° direction indicates the horizontal direction (second direction).

  (Comparative Example) FIG. 14 shows a case where the array antenna substrate 100 has an arrangement pitch Ps of the slots 3a equal to the arrangement pitch Pa2 of the antenna elements, both being 2 mm which is 1/2 (λ0 / 2) of the free space wavelength λ0 The (comparative example) radiation pattern is shown. In the simulation array unit 120, four antenna element regions 110 are arranged only in the second direction as in the example shown in FIG. 1, but unlike the example shown in FIG. This is a case where the antenna element region 110 is located at the center in the second direction. According to FIG. 14, the zenith direction has a gain of 10.41 dBi, but a side lobe of 5.34 dB occurs in the direction of about −30 °. When such a side lobe occurs, an object in an unintended direction may be detected when the radar direction is detected.

  Example 1 FIG. 15 shows a radiation pattern in the case of an array antenna substrate 100 of Example 1 such as the example shown in FIG. That is, the array part 120 of the simulation model has four antenna element regions 110 arranged only in the second direction as in the example shown in FIG. The arrangement pitch Ps of the slots 3a is 1.9 mm which is one times the effective wavelength λg of the signal transmitted through the feed line conductor 4, and is shorter than 2 mm of the arrangement pitch Pa of the antenna element region 110. The slot 3a of the antenna element region 110 on the tip end 4b side of the feed line conductor 4 is located at the center of the antenna element region 110 in the second direction. In other words, the first antenna element region 111 is farthest from the feed end 4 a of the feed line conductor 4. According to FIG. 15, the zenith direction has a gain of 11.36 dBi, and the side lobe in the direction of about −30 ° is 0.5 dBi, which is lower than the case of FIG. In this way, by setting the arrangement pitch Ps of the slots 3a to be an integral multiple of the effective wavelength λg of the transmission line, the resonance timings of the four antennas (antenna element regions 110) are matched and the side lobe is reduced. It can be said that a high radiation pattern was obtained.

  (Example 2) FIG. 16 is a radiation pattern of the array antenna substrate 100 of Example 2 like the example shown in FIG. That is, it is a radiation pattern when the array unit 120 of the example shown in FIG. 1 showing two radiation patterns as shown in FIG. 15 is arranged in two rows in the first direction. The array section 120 of the simulation model has four antenna element regions 110 arranged in the second direction and two rows in the first direction as in the example shown in FIG. Also in this case, the arrangement pitch Ps of the slots 3a in the second direction is 1.9 mm which is one times the effective wavelength λg of the signal transmitted through the feeder line conductor 4, and the antenna element region 110 in the second direction It is shorter than 2 mm of the arrangement pitch Pa (Pa2). In both rows, the first antenna element region 111 is disposed at a position farthest from the feed end 4 a of the feed line conductor 4. According to FIG. 16, the zenith gain is 13.75 dBi, and the side lobe is 3.48 dBi. Since the array unit 120 has two rows, the gain is higher than in the case of one row.

(Example 3) FIG. 17 is a radiation pattern of the array antenna substrate 100 of Example 3 like the example shown in FIG. That is, the simulation model array unit 120 includes four antenna element regions 110 arranged in the second direction and two columns in the first direction as in the example shown in FIG. The first antenna element region 111 is disposed at a position closest to the feeding end 4 a of the feeding line conductor 4. Also in this case, the arrangement pitch Ps of the slots 3a in the second direction is 1.9 mm which is one times the effective wavelength λg of the signal transmitted through the feeder line conductor 4, and the antenna element region 110 in the second direction It is shorter than 2 mm of the arrangement pitch Pa (Pa2). According to FIG. 17, the gain is 13.71 dBi, the side lobe is 1.96 dBi, and FIG. 16 shows the case where the first antenna element region 111 is located farthest from the feed end 4 a of the feed line conductor 4. The side lobe is lower than the radiation pattern shown. This is because the antenna element region 110 close to the feeding end 4a is the first antenna element region 111 in which the slot 3a is located at the center. In this case, the power fed to the first antenna element region 111 closest to the feed end 4a is the largest, and the radiation pattern formed by the antenna of the first antenna element region 111 becomes dominant, and therefore the radiation of the entire array antenna The side lobe of the pattern is low and the directivity is strong.

  (Example 4) FIG. 18 is a radiation pattern of the array antenna substrate 100 of Example 4 like the example shown in FIG. That is, the simulation model array unit 120 includes four antenna element regions 110 arranged in the second direction and two columns in the first direction as in the example shown in FIG. In one of the rows, the first antenna element region 111 is disposed at a position closest to the feeding end 4 a of the feed line conductor 4, and in the other row, the first antenna element region 111 is farthest from the feeding end 4 a of the feed line conductor 4. Placed in position. Also in this case, the arrangement pitch Ps of the slots 3a in the second direction is 1.9 mm, which is one times the effective wavelength λg of the signal transmitted through the feeder line conductor 4, and the antenna element region 110 in the second direction. It is shorter than 2 mm of the arrangement pitch Pa (Pa2). According to FIG. 18, the gain is 13.61 dBi and the side lobe is 2.48 dB. This side lobe shows an intermediate value between the side lobe of the radiation pattern shown in FIG. 16 and the side lobe of the radiation pattern shown in FIG. 17, but the gain in the ± 90 ° direction is shown in FIGS. It is lower than the radiation pattern shown. For this reason, it is possible to reduce radar direction detection errors caused by side lobes in the ± 90 ° direction. In particular, when the array antenna substrate 100 is used for a beam forming radar, the possibility of detecting an unnecessary object is reduced.

  Example 5 FIG. 19 is a graph showing the relationship between the width W of the strip-shaped conductor 21 and the gain in the array antenna substrate 100 of Example 5 as in the example shown in FIG. In the array section 120 of the simulation model, four antenna element regions 110 are arranged only in the second direction as in the example shown in FIG. 11B, and the arrangement pitch Ps of the slots 3 a is transmitted by the feed line conductor 4. 1.9 mm, which is one times the effective wavelength λg of the signal to be generated, shorter than 2 mm of the arrangement pitch Pa of the antenna element region 110, and the first antenna element region 111 is farthest from the feed end 4 a of the feed line conductor 4. Is. FIG. 19 is a plot of gain values when the width W of the strip-shaped conductor 21 positioned at both ends in the first direction is 0.15 mm, 0.5 mm, 1 mm, 1.5 mm, and 2 mm. . According to FIG. 19, the gain increases as the width W of the strip conductor 21 increases, and the gain increases when the width W of the strip conductor 21 is 1.0 mm or more and has a peak value when the width W is 1.5 mm. I understand. This is because although the graph showing the radiation characteristics is not shown, the side lobe becomes smaller when the width W of the strip conductor 21 is 1.0 mm or more. The gain of one antenna element is about 7 dBi. When four antennas are arranged as shown in FIG. 11B, the gain can be increased up to four times. A gain of 4 times corresponds to +6 dB, so that a gain of 7 dBi + 6 dB = 13 dBi can be obtained. As can be seen from FIG. 19, when the width W of the strip-shaped conductor 21 is 1.0 mm to 2.0 mm, the gain is as high as about 12.6 dBi or more, and when the width W is 1.5 mm, the maximum value is 13.0 dBi. As described above, the frequency of the high-frequency signal is 79 GHz, and 1/4 of the free space wavelength λ0 at 79 GHz is 1 mm, and 1/2 is 2 mm. That is, it can be said that when the width W of the belt-like conductor 21 is in the range of λ0 / 4 to λ0 / 2, the gain is almost the maximum (about 97% or more of the maximum gain). Thus, by setting the width w of the strip conductor 21 to λ0 / 4 to λ0 / 2 or less, the array antenna substrate 100 having a small size and a high gain is obtained.

DESCRIPTION OF SYMBOLS 1 ... Dielectric substrate 1a ... Dielectric layer 11 ... 1st surface 12 ... 2nd surface 2 ... Surface conductor 2a ... Opening 21 ... Band-shaped conductor 22 ... Connection conductor 3 ... grounding conductor 3a ... slot 4 ... feed line conductor 4a ... feed end 4b ... tip 5 ... through conductor 5a ... interlayer conductor 6 ... second Ground conductor 7 ... electrode 8 ... feeding wiring conductor 100 ... array antenna substrate 110 ... antenna element region 111 ... first antenna element region 120 ... array portion 121 ... first Row 122... Second row 130... Mounted portion 200... Semiconductor element 300.

Claims (6)

A plurality of dielectric layers, a dielectric substrate having a first surface and a second surface;
A surface conductor provided on the first surface of the dielectric substrate and having an opening for transmitting or receiving a high-frequency signal; a ground conductor having a slot whose length direction is the first direction; Feed line conductors in a second direction orthogonal to the first direction are arranged in this order so as to face each other with the dielectric layer interposed therebetween, and have a predetermined circumferential shape along the opening. An antenna element region in which the surface conductor and the ground conductor are electrically connected by a plurality of through conductors provided at intervals and penetrating the dielectric layer;
An array unit in which a plurality of antenna element regions are arranged in contact with each other in at least the second direction;
With
The feeder line conductor is connected in series between the plurality of antenna element regions arranged in the second direction and extends in the second direction,
When the free space wavelength of the high frequency signal is λ ₀ ,
The arrangement pitch of the antenna element region is an odd multiple of λ _0/2,
The array antenna substrate, wherein an arrangement pitch of the slots in the second direction is an integral multiple of an effective wavelength of a signal transmitted through the feeder line conductor. The plurality of antenna element regions arranged in the second direction includes a first antenna element region in which the slot is located in the center of the second direction in the antenna element region, and the first antenna 2. The array antenna according to claim 1, wherein the element region is located closest to a feeding end of the feeding line conductor in the second direction. One of the array portions is configured by a plurality of rows in which a plurality of the antenna element regions are arranged in contact with each other in the first direction, and the slot is positioned at the center of the second direction in the antenna element region. A first row in which the first antenna element region is closest to the feed end of the feed line conductor, and a second row in which the first antenna element region is farthest from the feed end of the feed line conductor. The array antenna substrate according to claim 1, wherein the array antenna substrate is disposed adjacent to each other in one direction. Of the strip-shaped conductors that are located across the opening in the first direction, the width of the strip-shaped conductors that are positioned at both ends of the array portion in the first direction is the freedom of the high-frequency signal. array antenna substrate according to any one of claims 1 to 3 is λ _{0 /} 4~λ _0/2 when the spatial wavelength is lambda _0. The array antenna substrate according to claim 1, further comprising a semiconductor element mounting portion on a second surface opposite to the first surface of the dielectric substrate. A communication module in which a semiconductor element is mounted on the mounting portion of the array antenna substrate according to claim 5.

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