Phased array antenna

Abstract

This phased array antenna comprises a microstrip line, a first substrate on the microstrip line, a common electrode on the first substrate, a second substrate on the common electrode, and at least one antenna electrode that is positioned on the second substrate and overlaps the microstrip line and the common electrode. The common electrode has a slot that overlaps the microstrip line and the at least one antenna electrode in the normal direction to the first substrate.

Description

Phased array antenna

[0001] One embodiment of the present invention relates to a phased array antenna.

[0002] A phased array antenna is an antenna that regularly arranges a plurality of antenna elements and transmits directional radio waves by adjusting the phase of each antenna. For example, Patent Document 1 discloses that driving a plurality of antennas in groups can achieve both higher-speed phase error correction processing and improved correction accuracy.

[0003] Japanese Patent No. 5578885

[0004] One object of an embodiment of the present invention is to provide an antenna element having a novel structure, and a phased array antenna including the antenna element. Alternatively, one object of an embodiment of the present invention is to provide a phased array antenna that can be manufactured with high yield at low cost and can have any size.

[0005] One embodiment of the present invention is a phased array antenna. The phased array antenna comprises: a microstrip line; a first substrate disposed on the microstrip line; a common electrode disposed on the first substrate; a second substrate disposed on the common electrode; and at least one antenna electrode located on the second substrate, overlapping the microstrip line and the common electrode. The common electrode has a slot that overlaps the microstrip line and the at least one antenna electrode in a normal direction of the first substrate.

[0006] A schematic top view of a phased array antenna according to one embodiment of the present invention. A schematic top view of a phased array antenna according to one embodiment of the present invention. A schematic end view of a phased array antenna according to one embodiment of the present invention. A schematic top view of a phased array antenna according to one embodiment of the present invention. A schematic end view of a phased array antenna according to one embodiment of the present invention. A schematic top view of a phased array antenna according to one embodiment of the present invention. A schematic end view of a phased array antenna according to one embodiment of the present invention. A schematic end view of a phased array antenna according to one embodiment of the present invention. A schematic top view of a phased array antenna according to one embodiment of the present invention. A schematic end view of a phased array antenna according to one embodiment of the present invention.

[0007] The embodiments of the present invention will be described below with reference to the drawings and other materials. However, the present invention can be implemented in various forms without departing from its spirit, and is not to be interpreted as being limited to the embodiments described below.

[0008] While drawings may schematically represent the width, thickness, shape, etc., of each part compared to the actual embodiment in order to clarify the explanation, these are merely examples and do not limit the interpretation of the present invention. In this specification and each drawing, elements having the same function as those described with respect to previously shown drawings are denoted by the same reference numeral, and redundant explanations may be omitted. This reference numeral is used to indicate multiple identical or similar components collectively, and when these components are indicated individually, a hyphen and a natural number are used after the reference numeral. Furthermore, when indicating a part of a single component, a lowercase alphabet letter is used after the reference numeral.

[0009] In this specification and claims, when describing a manner in which one structure is placed on top of another structure, unless otherwise specified, the term "on top of" includes both cases: when one structure is placed directly on top of another structure so as to be in contact with it, and when another structure is placed above another structure via yet another structure.

[0010] In this specification and claims, the expression "one structure is exposed from another structure" means a part of one structure that is not covered by the other structure, and this part that is not covered by the other structure may be covered by yet another structure. The hierarchical relationship between one structure and the other structure is irrelevant. Furthermore, the embodiment described by this expression also includes a form in which one structure is not in contact with the other structure.

[0011] In this invention, when a single film is processed to form multiple films, these multiple films may have different functions and roles. However, these multiple films originate from a film formed as the same layer in the same process, and have substantially the same layer structure, the same material, and the same morphology. Therefore, these multiple films are defined as existing in the same layer.

[0012] <First Embodiment> Hereinafter, an antenna element and a phased array antenna including the same, according to one embodiment of the present invention, will be described.

[0013] 1. Overall Structure of Phased Array Antenna A phased array antenna is a collection of multiple antenna elements arranged in a straight line, curve, or matrix, and is a device that emits radio waves based on the AC signal (AC potential) supplied to each antenna element. Furthermore, by adjusting the phase of each antenna element, it is possible to emit radio waves with strong directivity in any direction. There are no restrictions on the frequency of radio waves that can be emitted by a phased array antenna according to one embodiment of the present invention; for example, it is possible to emit radio waves in the frequency range of 400 MHz to 50 GHz. Typically, this phased array antenna can be used to emit radio waves in the 400 MHz to 6.0 GHz band, the 2.5 GHz to 4.7 GHz band, and the 24 GHz to 50 GHz band.

[0014] Figure 1 shows a schematic top view of the phased array antenna 100. The phased array antenna 100 comprises a first substrate 112 and a second substrate 114 that overlap each other in the direction normal to each other, and various patterned insulating films, semiconductor films, conductive films, etc. are arranged on the surfaces of the first substrate 112 and the second substrate 114. By appropriately stacking these films, the phased array antenna 100, which includes a microstrip line 120 and at least one antenna element 110, is constructed. An AC potential is supplied to the microstrip line 120 from an external circuit (not shown). As will be described later, the AC potential supplied to the microstrip line 120 is transmitted to the antenna element 110, and radio waves are emitted from the antenna element 110.

[0015] At least one antenna element 110 can include multiple antenna elements 110, in which case, as shown in Figure 1, the multiple antenna elements 110 can be arranged in a single line in one direction. However, there are no restrictions on the number or arrangement of the antenna elements 110; any number of antenna elements 110 may be arranged on a circumference, or they may be arranged in a matrix shape having multiple rows and multiple columns.

[0016] Figure 2 shows a schematic top view of a portion of the phased array antenna 100, and Figure 3 shows a schematic end view along the dashed line A-A' in Figure 2. Figure 2 shows an example in which two antenna elements 110 are formed. As shown in these figures, the antenna element 110 includes a common electrode 116 and an antenna electrode 118, and the antenna function is realized by the common electrode 116, the antenna electrode 118, and a second substrate 114 located between them. The second substrate 114 functions as a dielectric for the antenna. The various components of the phased array antenna 100 will be described below.

[0017] 2. The first substrate and the second substrate The first substrate 112 and the second substrate 114 provide physical strength to the phased array antenna 100 and provide surfaces for arranging antenna elements 110 and microstrip lines 120. The first substrate 112 and the second substrate 114 may include inorganic insulators such as glass and quartz, semiconductors such as silicon, polymers such as polyimide, polycarbonate, and polyester, and metals such as aluminum, copper, and stainless steel. Preferably, an inexpensive and readily available glass substrate is used as a large substrate. The first substrate 112 and the second substrate 114 may or may not transmit visible light. The first substrate 112 and / or the second substrate 114 may also be flexible. If the first substrate 112 and / or the second substrate 114 contain a conductive material such as metal, it is preferable to provide a protective insulating film (not shown) on its surface. The protective insulating film may consist of one or more films containing silicon-containing inorganic compounds such as silicon oxide or silicon nitride.

[0018] 3. Microstrip Line The microstrip line 120 is configured to transmit pulsed AC signals supplied directly from an external circuit or via a drive circuit (not shown) to the antenna element 110. As can be seen from Figure 3, the microstrip line 120 is provided on the underside of the first substrate 112 directly or via a protective insulating film (not shown). The microstrip line 120 may be configured to include a metal such as titanium, molybdenum, tungsten, copper, or aluminum, or an alloy containing a metal selected from these.

[0019] The microstrip line 120 is a wiring with a large aspect ratio (for example, a length / width ratio of 2 to 500). The width of the microstrip line 120 can be set to, for example, 20 μm to 500 μm. The pattern of the microstrip line 120 can also be arbitrarily set, and for example, as shown in Figure 1, the microstrip line 120 can be formed to have one or more branching structures. Since one antenna element 110 is placed at each end of the microstrip line 120, by adopting such a branching structure, AC signals can be transmitted from one input terminal to multiple antenna elements.

[0020] 4. Common Electrode As shown in Figure 3, the common electrode 116 is provided between the first substrate 112 and the second substrate 114. Therefore, the first substrate 112 is sandwiched between the common electrode 116 and the microstrip line 120. Similar to the microstrip line 120, the common electrode 116 can be configured to include a metal such as titanium, molybdenum, tungsten, copper, or aluminum, or an alloy containing a metal selected from these. A protective insulating film may be provided between the first substrate 112 and the common electrode 116, and / or between the second substrate 114 and the common electrode 116. A constant potential (e.g., ground potential) is supplied to the common electrode 116 from an external circuit. As shown in Figures 2 and 3, the common electrode 116 is positioned to overlap with the microstrip line 120 and the antenna electrode 118 in the direction normal to the first substrate 112 and the second substrate 114. When multiple antenna elements 110 are provided, the common electrode 116 of each antenna element 110 is integrated and arranged as a single electrode that overlaps with all the antenna electrodes 118.

[0021] Here, the common electrode 116 is provided with an opening (slot) 116a corresponding to each antenna electrode 118. The number of openings 116a is equal to or greater than the number of antenna elements 110. Therefore, if the phased array antenna 100 has multiple antenna elements 110, multiple openings 116a are provided on the common electrode 116. The openings 116a have an aspect ratio greater than 1, and preferably have a rectangular shape in plan view (viewed from the normal direction of the first substrate 112 or the second substrate 114; the same applies hereinafter). The arrangement of the openings 116a with respect to the microstrip line 120 and the antenna electrodes 118 will be described later.

[0022] 5. Antenna Electrodes As can be seen from Figures 2 and 3, the antenna electrode 118 is placed on the second substrate 114 either directly or via a protective insulating film (not shown). Thus, the second substrate 114 is sandwiched between the antenna electrode 118 and the common electrode 116. Furthermore, the antenna electrode 118 does not physically contact the microstrip line 120, but is separated from the microstrip line 120 via the first substrate 112 and the second substrate 114. Similar to the microstrip line 120, the antenna electrode 118 can also be configured to include a metal such as titanium, molybdenum, tungsten, copper, or aluminum, or an alloy containing a metal selected from these.

[0023] As shown in Figure 2, the antenna electrode 118 includes an output section 118a and a wiring section 118b, and the output section 118a and the wiring section 118b are integrated to form the antenna electrode 118. Therefore, the output section 118a and the wiring section 118b have the same composition and the same thickness. The wiring section 118b has the main function of transmitting the AC signal transmitted from the microstrip line 120 to the output section 118a. The output section 118a emits radio waves of a frequency corresponding to the AC signal transmitted from the wiring section 118b. For this reason, it is preferable that the output section 118a be formed in a shape such as a regular polygon including a square or a circle, having multiple axes parallel to its main plane and intersecting each other as axes of symmetry. For example, although it depends on the frequency of the radio waves emitted by the phased array antenna 100, the shape of the output section 118a can be adjusted to have a square shape with sides of 2 mm or more and 30 mm or less.

[0024] On the other hand, the wiring section 118b is formed as wiring with a relatively high aspect ratio, and its width (length in the direction perpendicular to the extension direction or longitudinal direction) is shorter than the width (length in the said direction) of the output section 118a. The antenna electrode 118 is positioned so as to overlap with the common electrode 116 and the microstrip line 120 in the direction normal to the first substrate 112 and the second substrate 114. More specifically, the output section 118a overlaps with the common electrode 116 but not with the microstrip line 120, and the antenna electrode 118 is positioned so that the wiring section 118b overlaps with the common electrode 116 and its opening 116a, and the microstrip line 120.

[0025] 6. Common Electrode Aperture and its Arrangement The opening 116a formed in the common electrode 116 does not overlap with the output section 118a of the antenna electrode 118 in the direction normal to the first substrate 112 or the second substrate 114 (Figure 2), but it overlaps with the wiring section 118b via the second substrate 114 and with the microstrip line 120 via the first substrate 112 (Figure 3). In other words, the microstrip line 120 is exposed from the common electrode 116 at the opening 116a and overlaps with the wiring section 118b on the opening 116a. Therefore, although the microstrip line 120 and the wiring section 118b do not physically contact each other, the AC signal supplied to the microstrip line 120 is transmitted to the wiring section 118b by electromagnetic field coupling, and radio waves of a frequency corresponding to this AC signal can be output from the output section 118a.

[0026] To more effectively transmit AC signals from the microstrip line 120 to the antenna electrode 118, it is preferable that the opening 116a be provided so as to completely cross the microstrip line 120 and the wiring section 118b. That is, it is preferable to provide an opening 116a that is rectangular or substantially rectangular in shape when viewed from above, with its longer side overlapping the entire microstrip line 120 and the wiring section 118b. Preferably, the longitudinal direction of the opening 116a is perpendicular to the longitudinal direction of the wiring section 118b and the extending direction of the microstrip line 120. Furthermore, it is preferable that the center of the opening 116a coincides with the center of the wiring section 118b and the microstrip line 120. More specifically, it is preferable that the center of the opening 116a (or, if the opening 116a is assumed to be a tangible object, its centroid) coincides with the centerline of the wiring section 118b (the centerline in a direction parallel to the longitudinal direction of the wiring section 118b). Similarly, it is preferable that the center of the opening 116a coincides with the center line of the portion of the microstrip line 120 that overlaps with the opening 116a (the center line in a direction parallel to the extension direction of the microstrip line 120). By adopting such an arrangement, highly efficient electromagnetic field coupling can be achieved.

[0027] Furthermore, as can be seen from the simulation results, the width of the opening 116a, that is, the length W in the longitudinal direction of the opening 116a,ｓ (See Figure 2) The width W of the wiring section 118b is shown. ａ Preferably, the length Ls of the opening 116a, that is, the length of the opening 116a in the direction perpendicular to the extension direction of the wiring section 118b (see Figure 2), is 2.2 to 3.3 times the length of the opening 116a in the direction perpendicular to the extension direction of the wiring section 118b. Furthermore / or, the length Ls of the opening 116a, that is, the length of the opening 116a in the short direction (see Figures 2 and 3), is the length L of the wiring section 118b in the longitudinal direction of the portion of the wiring section 118b that overlaps with the microstrip line 120. Ｏ (See Figure 3) Preferably, it is 0.25 times or more and 1.25 times or less. For example, the frequency of the transmitted radio waves is 28 GHz, the thickness of the first substrate 112 and the second substrate 114 is 0.5 mm, and the length L Ｏ When the length is 1.248 mm and the width of the wiring section 118b and the microstrip line 120 is 0.76 mm, the preferred length Ls and width Ws of the opening 116a are 0.642 mm and 1.0 mm, respectively.

[0028] The phased array antenna 100 having the structure described above can be manufactured by forming microstrip lines 120 and antenna electrodes 118 on a first substrate 112 and a second substrate 114, respectively, forming a common electrode 116 on either the first substrate 112 or the second substrate 114, and then bonding the first substrate 112 and the second substrate 114 together. Furthermore, AC signals can be transmitted using electromagnetic field coupling without directly connecting the microstrip lines 120 and the antenna electrodes 118. Therefore, it is not necessary to form through holes or conductive via metals to fill them in the first substrate 112 and the second substrate 114, which are necessary for the physical connection between the microstrip lines 120 and the antenna electrodes 118. In order to impart a certain strength to the phased array antenna 100, the first substrate 112 and the second substrate 114 are required to have a certain thickness. For example, when glass substrates are used for the first substrate 112 and the second substrate 114, a thickness of several hundred micrometers (e.g., 300 μm to 600 μm) is required. Forming through holes in such relatively thick glass substrates is not always easy and can lead to increased cycle time and manufacturing costs, as well as a decrease in yield.

[0029] However, as described above, in the manufacturing of the phased array antenna 100 according to the embodiment of the present invention, it is not necessary to form through holes in the first substrate 112 and the second substrate 114. Therefore, it is possible to manufacture the phased array antenna 100 at low cost and with good yield. Furthermore, since it is also possible to use large glass substrates as the first substrate 112 and the second substrate 114, by applying the embodiment of the present invention, it is possible to provide a phased array antenna with good yield and at low cost.

[0030] <Second Embodiment> In this embodiment, a modified version of the phased array antenna 100 described in the first embodiment will be described. Configurations that are the same as or similar to the configuration described in the first embodiment may be omitted from the description.

[0031] 1. Modification 1 When bonding the first substrate 112 and the second substrate 114, a sealing material may be used to protect the antenna element 110 or a part of it from the outside air. Specifically, as shown in Figure 4 and the schematic diagram of the end face along the dashed line B-B' (Figure 5), the sealing material 102 may be arranged to surround all of the antenna element 110 in a plan view. The sealing material 102 may be configured to include, for example, a photocurable or thermosetting resin. This protects the antenna element 110 from the outside air. For example, by appropriately controlling the environment when bonding the first substrate 112 and the second substrate 114, the space surrounded by the first substrate 112, the second substrate 114, and the sealing material 102 can be filled with an inert gas such as nitrogen or argon, or a humidity-controlled gas.

[0032] At this time, in order to stably maintain the distance between the first substrate 112 and the second substrate 114, that is, the distance between the microstrip line 120 and the antenna electrode 118, and to achieve stable electromagnetic field coupling, a spacer 104 may be provided between the first substrate 112 and the second substrate 114 (Figure 5). The spacer 104 may be provided so as to overlap with the common electrode 116, or it may be provided in the opening 116a as shown in Figure 5. The shape of the spacer 104 may be columnar, spherical, or nearly spherical.

[0033] Alternatively, the sealing material 102 may be provided to surround only a part of the antenna element 110, rather than the entire element. For example, as shown in Figure 6 and the schematic diagram of the end face along the dashed line C-C' (Figure 7), the sealing material 102 may be provided to surround one or more openings 116a in a plan view. In this case, the entire or partial sealing material 102 may overlap with the common electrode 116. Furthermore, as shown in Figure 8, the sealing material 102 may be provided to fill the opening 116a.

[0034] 2. Modification 2 The process for manufacturing the phased array antenna 100 includes a step of bonding a first substrate 112 and a second substrate 114. At this time, the common electrode 116 may be provided on either the first substrate 112 or the second substrate 114. Therefore, when the sealing material 102 overlaps with the common electrode 116, as shown in Figure 7, the sealing material 102 may be located above the common electrode 116 (i.e., on the second substrate 114 side), or as shown in Figure 9, the sealing material 102 may be located below the common electrode 116 (i.e., on the first substrate 112 side).

[0035] 3. Modification 3 A phase shifter may be provided on the phased array antenna 100 to adjust the phase of the AC signal transmitted from the microstrip line 120 to the antenna electrode 118. Schematic top views of the phased array antenna 100 with the phase shifter are shown in Figures 10 and 11, and a schematic end view along the dashed line D-D' in Figure 11 is shown in Figure 12. As shown in Figure 12, the phased array antenna 100 of this modification further has a third substrate 140 provided below the first substrate 112, and a drive circuit 130 for controlling the phase shifter is provided on the third substrate 140 (see Figure 10). The third substrate 140 can be any substrate that can be used for the first substrate 112 or the second substrate 114. Therefore, for example, the third substrate 140 is a glass substrate. The drive circuit 130 may also be composed of various insulating films, semiconductor films, conductive films, etc., patterned on the third substrate 140, or it may be composed of a circuit (such as an integrated circuit) formed on a substrate independent of the third substrate 140 (for example, a semiconductor substrate). Multiple terminals (not shown) are formed on the third substrate 140, and various signals are supplied to the drive circuit 130 from an external circuit (not shown) via these terminals. The drive circuit 130 generates signals (scanning signals and control signals) for controlling the phase shifter based on the supplied signals and supplies them to the phase shifter.

[0036] The phase shifter may consist of electronic elements such as transistors and capacitive elements, and liquid crystal elements. In the example shown in Figures 11 and 12, the phase shifter consists of a transistor 150 and a liquid crystal element 170 connected to the transistor 150. The transistor 150 is connected to a gate line 152 and a signal line 158 extending from the drive circuit 130, and these are supplied with scanning signals to control the on / off state of the transistor 150 and control signals to control the liquid crystal element 170. The transistor 150 is provided on the third substrate 140 via a protective insulating film 142, either directly or in any configuration. There are no restrictions on the configuration of the transistor 150, and any known structure may be used as appropriate. In the examples shown in Figures 11 and 12, the transistor 150 is a bottom-gate type transistor and consists of a gate electrode 152a which is part of the gate line 152, a gate insulating film 154 on the gate electrode 152a, a semiconductor film 156 which overlaps with the gate electrode 152a via the gate insulating film 154, a source electrode 158a which is electrically connected to the semiconductor film 156 and is part of the signal line 158, and a drain electrode 160 which is electrically connected to the semiconductor film 156. Since the transistor 150 can be constructed using known materials and methods, a detailed explanation is omitted.

[0037] A planarization film 162 is provided on the transistor 150, and a liquid crystal element 170 is provided on top of it. The liquid crystal element 170 is composed of a bias electrode 172 connected to the drain electrode 160, a first alignment film 174 on the bias electrode 172, a liquid crystal layer 176 on the first alignment film 174, and a second alignment film 178 on the liquid crystal layer 176. A microstrip line 120 is provided so as to overlap with the liquid crystal element 170. Since the liquid crystal element 170 can also be constructed using known materials and methods, a detailed explanation is omitted.

[0038] By supplying a potential to drive the liquid crystal element 170 from the drive circuit 130 via the transistor 150, the orientation of the liquid crystal molecules contained in the liquid crystal element 170 changes. This change in orientation leads to a change in the dielectric constant of the liquid crystal layer 176. The transmission speed of the AC signal supplied to the microstrip line 120 changes depending on the dielectric constant of the liquid crystal layer 176, and the greater the change in the dielectric constant of the liquid crystal layer 176, the greater the change in transmission speed. Furthermore, the change in dielectric constant depends on the electric field strength generated in the liquid crystal layer 176. Therefore, by controlling the potential applied to the bias electrode 172, the dielectric constant of the liquid crystal layer 176 can be controlled, and as a result, the transmission speed of the pulsed AC signal can be changed. This changes the phase of the AC signal transmitted to the antenna electrode 118 by electromagnetic field coupling.

[0039] Therefore, if the potential applied to the bias electrode 172 is the same for all antenna elements 110 of the phased array antenna 100, the phase of the pulsed AC signal applied to the antenna electrode 118 will be the same for all antenna elements 110. As a result, the phase of the radio waves emitted from each antenna element 110 will also be the same, and the direction of radio wave emission will be the direction in front of the phased array antenna 100 (the normal direction to the first substrate 112, etc.). On the other hand, if the potential of the bias electrode 172 is changed for each antenna element 110, the phase of the AC signal applied to the antenna electrode 118 will change for each antenna element 110. As a result, the wavefront of the radio wave will tilt from the normal direction to the first substrate 112, etc., and the direction of radio wave emission will tilt. Therefore, by changing the potential of the bias electrode 172 for each antenna element 110, it becomes possible to emit highly directional radio waves in any direction.

[0040] The embodiments described above as embodiments of the present invention can be combined and implemented as appropriate, insofar as they do not contradict each other. Furthermore, any additions, deletions, or design changes to components, or additions, omissions, or changes to processes based on these embodiments, made by those skilled in the art, are also included within the scope of the present invention, as long as they retain the essence of the present invention.

[0041] Any effects or benefits other than those brought about by the embodiments described above, if they are clear from the description herein or easily predictable to a person skilled in the art, are naturally considered to be brought about by the present invention.

[0042] 100: Phased array antenna, 102: Encapsulation material, 104: Spacer, 110: Antenna element, 112: First substrate, 114: Second substrate, 116: Common electrode, 116a: Aperture, 118: Antenna electrode, 118a: Output section, 118b: Wiring section, 120: Microstrip line, 130: Drive circuit, 140: Third substrate, 142: Protective insulating film, 150: Transistor, 152: Gate line, 152a: Gate electrode, 154: Gate insulating film, 156: Semiconductor film, 158: Signal line, 158a: Source electrode, 160: Drain electrode, 162: Planarization film, 170: Liquid crystal element, 172: Bias electrode, 174: First alignment film, 176: Liquid crystal layer, 178: Second alignment film

Claims

1. A phased array antenna comprising a microstrip line, a first substrate on the microstrip line, a common electrode on the first substrate, a second substrate on the common electrode, and at least one antenna electrode located on the second substrate and overlapping with the microstrip line and the common electrode, wherein the common electrode has a slot that overlaps with the microstrip line and the at least one antenna electrode in the direction normal to the first substrate.

2. The phased array antenna according to claim 1, wherein at least one antenna electrode is spaced apart from the microstrip line.

3. The phased array antenna according to claim 1, wherein at least one antenna electrode has an output portion that does not overlap with the microstrip line in the normal direction, and a wiring portion that overlaps with the slot and the microstrip line in the normal direction and has a width smaller than that of the output portion.

4. The phased array antenna according to claim 3, wherein the slot is rectangular, and the longitudinal direction of the slot is perpendicular to the longitudinal direction of the wiring section.

5. The phased array antenna according to claim 4, wherein the center of the slot is located on a center line parallel to the longitudinal direction of the wiring section.

6. The phased array antenna according to claim 4, wherein the longitudinal length of the slot is 2.2 times or more and 3.3 times or less the width of the wiring section.

7. The phased array antenna according to claim 4, wherein the length of the slot in the short direction is 0.25 to 1.25 times the length of the wiring portion in the longitudinal direction in the portion where the wiring portion and the microstrip line overlap each other.

8. The phased array antenna according to claim 1, wherein both the first substrate and the second substrate are glass substrates.

9. The phased array antenna according to claim 1, further comprising a sealing material surrounding at least one antenna electrode in a plan view.

10. The phased array antenna according to claim 1, further comprising a sealing material surrounding the slot in a plan view.

11. The phased array antenna according to claim 1, further comprising a sealing material in the slot.

12. The phased array antenna according to claim 1, further comprising spacers within the slots.

13. The phased array antenna according to claim 1, wherein the at least one antenna electrode includes a plurality of antenna electrodes.

14. The phased array antenna according to claim 1, further comprising a third substrate below the first substrate, and a liquid crystal layer between the third substrate and the first substrate.

15. The phased array antenna according to claim 14, further comprising a transistor between the third substrate and the liquid crystal layer, wherein the transistor is configured to switch the potential applied to the liquid crystal layer on and off.

16. The phased array antenna according to claim 14, wherein the third substrate is a glass substrate.

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