Antenna array with independent RFIC chips and antenna element grid arrangement

Abstract

To provide an antenna apparatus with distributed RFIC chips in which, since I / O pads of RFICs are aligned with feed points of antenna elements, transmission lines and / or additional redistribution layers between first and second layers may be avoided, allowing a compact, low-loss design.SOLUTION: An antenna apparatus includes a first component layer having a plurality of RFICs 110 arranged in a first lattice geometry (e.g., rectangular), where each RFIC comprises beamforming circuitry. A second, parallel component layer overlays the first component layer and includes a plurality of antenna elements 120 arranged in a second, different lattice geometry (e.g., triangular). The antenna elements have respective feed points 122 each coupled to an input / output (I / O) pad of an RFIC. Each I / O pad is aligned with the feed point coupled to the I / O pad along an axis orthogonal to the first and second layers.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] (Related Application) This patent application claims the benefit of priority from U.S. Provisional Patent Application No. 63 / 011,056, filed on April 16, 2020, entitled "Antenna Array with Independent RFIC Chip and Antenna Element Lattice Geometries", the entire content of which is incorporated herein by reference.

[0002] (Field of the Invention) The present disclosure relates generally to antenna arrays having distributed RFIC chips. [Background Art]

[0003] Discussion of Related Art Antenna arrays are currently used in various applications at microwave and millimeter wave frequencies, such as in aircraft, satellites, vehicles, and base stations for general terrestrial communications. Such antenna arrays typically include microstrip radiating elements driven using phase-shifted beamforming circuitry to form a phased array for directional beam steering. In many cases, it is desirable that the entire antenna system, including the antenna array and the beamforming circuitry, meets required performance metrics while occupying minimal low-profile space.

[0004] An "embedded" antenna array may be defined as an antenna array consisting of antenna elements integrated with a radio frequency integrated circuit chip (RFIC) in a compact structure. An embedded array can have a sandwich configuration where the antenna elements are located within an external component layer, and the RFIC is distributed across the effective antenna aperture in adjacent, parallel component layers behind the antenna element layer. The RFIC may include a power amplifier (PA) for transmission, a low-noise amplifier (LNA) for reception, and / or a phase shifter for beam steering. By distributing the PA and LNA in this manner, higher efficiency during transmission and improved noise performance during reception can be achieved. The reliability of the antenna array can also be improved, as the overall antenna performance remains acceptable even if a few of the amplifiers malfunction. The RFIC typically includes other beamforming circuits such as filters, impedance matching elements, RF couplers, transmit / receive (T / R) switches, and control lines. [Overview of the Initiative]

[0005] In one aspect of the present disclosure, the antenna device includes a first component layer comprising a plurality of RFICs arranged in a first plane having a first grid arrangement, each RFIC comprising a beamforming circuit. A second component layer is superimposed on the first component layer and comprises a plurality of antenna elements arranged in a second plane parallel to the first plane in a second different grid arrangement. Each antenna element has its own feed point connected to the input / output (I / O) pads of the RFIC. The I / O pads are aligned with the feed points connected to the I / O pads along axes perpendicular to the first and second planes.

[0006] The first grid arrangement may be rectangular, and the second grid arrangement may be triangular.

[0007] Because the RFIC's I / O pads are aligned with the feed points of the antenna elements, additional rewiring layers between the transmission lines and / or the first and second layers can be avoided, enabling a compact and low-loss design. [Brief explanation of the drawing]

[0008] The above and other aspects and features of the disclosed technology will become more apparent from the following detailed description in conjunction with the accompanying drawings, in which similar reference numerals indicate similar elements or features. Different elements of the same or similar type may be distinguished by adding a dash and a second label to the reference label to distinguish them between the same / similar elements (e.g., -1, -2), or by adding the second label directly to the reference label. However, if a given description uses only the first reference label, it is applicable to any one of the same / similar elements having the same first reference label, regardless of the second label. Elements and features may not be depicted to the scale of the drawings. [Figure 1] This is a plan view of an exemplary antenna device according to one embodiment. [Figure 2] This figure shows an example of the grid arrangement of antenna elements and RFIC in the antenna device shown in Figure 1. [Figure 3] This is a cross-sectional view of a portion of the antenna device along line 3-3 in Figure 1. [Figure 4A] This is a cross-sectional view showing an example of the connection structure between an antenna element and an RFIC in an antenna device. [Figure 4B] This is a cross-sectional view along line 4B-4B in Figure 4A, showing the ground-signal-ground connection configuration. [Figure 5] This is a cross-sectional view showing another example of the connection structure between an antenna element and an RFIC in an antenna device. [Figure 6] This is a cross-sectional view of an exemplary flip-chip connection between an antenna element and an RFIC in an antenna device. [Figure 7A] This is a cross-sectional view of an exemplary dual via connection between an antenna element and an RFIC in an antenna device. [Figure 7B]Figure 7A is a cross-sectional view of an exemplary portion of an antenna device showing an exemplary extension connection structure that includes a dual via type connection. [Figure 8A] Examples of antenna feed point configurations for connected RFICs are shown. [Figure 8B] Examples of antenna feed point configurations for connected RFICs are shown. [Figure 8C] Examples of antenna feed point configurations for connected RFICs are shown. [Figure 9] This figure shows an exemplary layout of a beamforming circuit within an RFIC having I / O pads arranged according to the configuration shown in Figure 8B. [Modes for carrying out the invention]

[0009] The following description is provided, with reference to the accompanying drawings, to assist in a comprehensive understanding of specific exemplary embodiments of the technology disclosed herein for illustrative purposes. While this specification includes various specific details to assist those skilled in the art in understanding the technology, these details should be considered illustrative only. For the sake of brevity and clarity, descriptions of well-known functions and structures may be omitted if they would obscure those skilled in the art in understanding the technology.

[0010] Figure 1 is a top view of an exemplary antenna device 100 according to one embodiment. The antenna device 100 may consist of a thin laminated structure having an upper component layer comprising a plurality of antenna elements 120 forming an antenna array in a first plane, and a lower component layer comprising a plurality of radio frequency integrated circuit chips (RFICs) 110 arranged in a second plane parallel to the first plane and connected to the antenna elements 120. A substrate 150 may be placed between the upper component layer and the lower component layer. A ground plane (not shown) for reflecting signal energy between the antenna elements 120 and the substrate 150 may be printed on the underside of the substrate 150. Such a multilayer structure with integrated antenna elements 120 and RFICs 110 is sometimes referred to as an embedded antenna array. In the following description, for convenience of explanation, horizontal plane / direction generally refers to a plane / direction parallel to the main plane of the antenna device 100, and vertical direction refers to an orthogonal direction, i.e., the thickness direction of the antenna device 100.

[0011] Each antenna element 120 may be a microstrip patch antenna element printed on the substrate 150 and electrically or electromagnetically coupled ("fed") to the RFIC 110 at its respective feed point 122. The RFIC 110 can be mechanically connected to the substrate 150, such as by solder bump connections to a ground plane and other connection pads located on the substrate 150. Each RFIC 110 may include transmit and / or receive RF front-end circuits, including amplifiers, phase shifters, and filters. (In this specification, RF front-end circuits may be interchangeably referred to as "beamforming" circuits.) With RF front-end amplifiers thus distributed across the antenna array, the antenna device 100 may be referred to as an active antenna array. In some embodiments, each RFIC 110 includes a receive circuit comprising at least one low-noise amplifier (LNA) for amplifying the received signal and at least one power amplifier (PA) for amplifying the transmitted signal. If the antenna device 100 is designed as a phased array, each RFIC 110 may include at least one dynamically controllable phase shifter for steering the receive beam and / or transmit beam.

[0012] In one embodiment, the antenna device 100 is configured for operation across the millimeter-wave frequency band, which is generally defined as the 30 GHz to 300 GHz range. In other examples, the antenna device 100 operates in the microwave range of approximately 1 GHz to 30 GHz, or in the sub-microwave range below 1 GHz. In this specification, radio frequency (RF) signals mean signals having frequencies between 1 GHz and below 300 GHz. Note that RFICs configured to operate at microwave or millimeter-wave frequencies are often called monolithic microwave integrated circuits (MMICs) and are typically fabricated from III-V semiconductor materials.

[0013] When implemented as a microstrip patch, the antenna elements 120 can have any suitable shape, such as square, rectangular, circular, elliptical, or variations thereof, and can be provided and configured in a manner sufficient to achieve the desired polarization, e.g., circular, linear, or elliptical. The number, type, size, shape, spacing between elements, and manner in which they are provided may be modified by design to achieve the target performance metrics. Figure 1 shows an example with 64 antenna elements 120, but in a typical embodiment, the antenna device 100 includes hundreds or thousands of antenna elements 120. In the embodiments described below, each antenna element 120 is a microstrip patch to which probe feeding is provided. Probe feeding may be implemented as through-board vias (TSVs) ("vias") electrically connected to the input / output (I / O) pads of the RFIC 110. The I / O pads are interfaces that allow signals to input and output to the RFIC 110. In other examples, an electromagnetic feeding mechanism is used instead of vias, and each antenna element 120 is excited by near-field energy from its respective feeding point.

[0014] In the antenna device 100, the RFIC 110 is arranged in a first grid configuration, and the antenna elements 120 are arranged in a second (different) grid configuration. In Figure 1 and other examples herein, the first grid configuration is rectangular (hereinafter, “square” is a subset of “rectangle”), and the second grid configuration is non-rectangular, e.g., triangular, but other combinations are possible in other embodiments. Non-rectangular antenna array grid configurations (e.g., triangular) can offer desirable performance advantages compared to rectangular grids, such as enabling wider spacing of antenna elements 120 with grating-loop-free performance. Coupling between antenna elements 120 can also be beneficially reduced in a triangular grid compared to a rectangular grid configuration.

[0015] In either case, the RFIC 110 and antenna elements 120 are arranged in different grid configurations, but each feed point 122 is vertically aligned with the corresponding I / O pad of the RFIC 110 connected to that feed point. For example, in Figure 1, the area of ​​each feed point 122 is represented as a "○", and the "×" within each "○" represents the connected RFIC 110 I / O pad. Thus, vertically, the feed point 122 overlaps with the I / O pad. In other words, the I / O pads of the various RFIC 110s arranged in the horizontal plane define a pattern that matches the pattern of the feed point 122. This matched configuration shortens the distance between each feed point 122 and the corresponding I / O pad, eliminating the need for lossy transmission lines that traverse them horizontally. Conventionally, these transmission lines are formed within the multilayer connection between the RFIC 110 and the antenna substrate 150. This is partly because the I / O pads on a standard RFIC are arranged symmetrically adjacent to the opposing edges of their rectangular footprints. This embodiment allows for the elimination of such multilayer connections and, otherwise, the reduction / elimination of losses caused by such transmission lines.

[0016] In FIG. 1, the positions of the feeding point 122 and the I / O pads of the RFIC 110 are shown vertically aligned. As used herein, "alignment" between a feeding point and a connected I / O pad can be either exact alignment (within manufacturing tolerances) or "substantial alignment" (described below) incorporating a slight offset for manufacturing purposes. FIG. 1 also shows a case where each RFIC 110 is connected to four antenna elements 120. In other embodiments, each RFIC 110 is connected to more or fewer antenna elements 120. It should also be noted that in some embodiments, each of the antenna elements 120 is shared for transmitting operation and receiving operation, and each RFIC 110 internally includes a suitable transmit / receive (T / R) circuit for separating signals in a transmission path and a reception path. However, in other antenna systems, two separate antenna arrays 100 are used, one for transmission and the other for reception. In this case, all antenna elements 120 of a given antenna array 100 are either "receiving antenna elements" dedicated to receiving operation or "transmitting antenna elements" dedicated to transmitting operation.

[0017] Each grid arrangement can be defined by the center point 123 of the antenna element 120 and the center point 113 of the RFIC 110. (Note that the feed point 122 may be offset from the center point 123 of the antenna element 120.) Referring to Figure 2, the imaginary lines connecting the center points 123 form the triangular grid 202 of the antenna element 120. The imaginary lines connecting the center points 113 of the RFIC 110 form the rectangular or square grid 204 of the RFIC 110. As seen in Figure 1, in the case of four antenna elements 120 connected to one RFIC 110 in such a grid arrangement, in any given RFIC 110, two I / O pads (x in the feed point 122) are located at opposing edges of the RFIC, and the other two I / O pads are located inward from the opposing edges. Generally, when each RFIC 110 in a rectangular grid is connected to at least two antenna elements 120 in a non-rectangular grid, some of the RFIC I / O pads may be located on opposing edges of the RFIC 110, while the remaining I / O pads are located inward from these opposing edges. This I / O pad arrangement differs from that of a standard RFIC (with a rectangular footprint) where all of its I / O pads are typically located close to opposing edges (including the "G" ports of ground-signal-ground ("GSG") or ground-signal ("GS") connection sets, as described later). As a result, when a standard RFIC is arranged in a rectangular grid and connected to antenna elements in a non-rectangular grid, some or all of the feed point locations will not be aligned with the I / O pad locations. This complicates the design by requiring horizontal transmission lines and makes interconnection between the RFIC and antenna elements difficult and lossy. This embodiment, using aligned feed points and I / O pads, avoids such complexity and transmission line losses.

[0018] FIG. 3 is a simplified cross-sectional view of a portion of an antenna device 100, showing an exemplary structure along the two adjacent RFICs 110 of FIG. 1. A plurality of vias 302 are formed in the substrate 150, each connecting a feeding point 122 of an antenna element 120 at an I / O pad position 315 to an RFIC 110 I / O pad (not shown in FIG. 3). Hereinafter, it is assumed that the I / O pad position 315 is the center position of the I / O pad. A detailed example of the I / O pad will be described later.

[0019] The ground plane 340 may be printed on the lower surface of the substrate 150. The position of the feeding point 122 and the corresponding I / O pad position 315 are vertically aligned, so that one or more redistribution layers having a horizontally oriented transmission line between the RFIC 110 and the substrate 150 can be avoided. Therefore, the RFIC 110 may be directly attached to connection points on the substrate 150 and the ground plane 340. Furthermore, the alignment between the I / O pad position 315 and the corresponding feeding point position 122 reduces the complexity of the antenna substrate 150 (including the number of required substrate layers). It should be noted that the number of dielectric layers and conductive layers in the antenna substrate 150 may vary depending on embodiments. In some embodiments, it should be further noted that each antenna element 120 may have two feeding points connected to two respective I / O pads of the RFIC 110 via two vias 302 to form circularly polarized waves in some designs. However, the design of the antenna element 120 described below utilizes single feeding to realize circularly polarized waves. Furthermore, when a GSG connection is made, the ground pad of the RFIC 110 may be connected to the ground plane 340 at positions 317 on both sides of the via 302. Alternatively, a GS connection is used in which the connection between a single ground pad and the ground plane 340 is made only on one side of the via 302.

[0020] Figure 4A is a cross-sectional view of an exemplary connection structure 400 between one antenna element 120 and the RFIC 110 in the antenna device 100. In this embodiment, "precise" vertical alignment of the feed point 122 and the touchpad position 315 is targeted by the design via 302. (Manufacturing tolerances, as described below, allow for a predetermined range of horizontal offset even in the case of this "precise alignment.") The via 302 electrically contacts the antenna element 120 at the location of the feed point 122, penetrates the antenna substrate 150, and connects the antenna element 120 to the catch pad 406 on the bottom surface 453 of the substrate 150. The location of the feed point 122 is the center of the electromagnetic interface with the antenna element 120. In the illustrated example, the via 302 is in direct contact with the antenna element 120, and therefore the feed point 122 is at the center of the top surface of the via 302. In other embodiments where the antenna element 120 does not physically contact the via but is capacitively coupled to the slot, the feed point may be located at the optimal coupling position of the slot.

[0021] For example, via 302 may be cylindrical and have a diameter D passing through the central axis 425, and the intersection of the axis 425 and the antenna element 120 defines the position of the feed point 122. (If via 302 has an elliptical cross-section, D can represent the distance across any cross-section of the ellipse.) For the purpose of manufacturing tolerances, the catch pad 406 may be welded and patterned from a conductive material that has a footprint having a diameter or width approximately the same as or slightly larger than the diameter D. The RFIC 110 has an I / O pad 412 connected to the catch pad 406 via an electrical connection joint 420s ("s" indicates a "signal" line connection). This connection enables signal communication between the antenna element 120 and a beamforming circuit (not shown) within the RFIC 110. The I / O pad 412 may be cylindrical, elliptical, or rectangular with respect to the central axis 435. The I / O pad position 315 may be defined as a position along the central axis 435. In the example of precise alignment shown in Figure 4A, the tolerance for the desired alignment between axes 435 and 425 (i.e., the allowable horizontal offset due to manufacturing variations) may be approximately 1 / 4 D. Such a minimum or zero offset minimizes the length of the signal path between the feed point 122 and the I / O pad position 315, given the antenna substrate 150 and the conductive bonding material (thickness of the connection joint 420s). This allows the antenna element 120 to be directly connected to the RFIC 110 via the via 302 and the conductive bonding material (e.g., solder) of the connection joint 420s without the need for additional transmission lines or multilayer connections. An example of the via 302 diameter D for millimeter-wave designs is in the range of 50 to 100 μm. The typical alignment accuracy of the RFIC 110 in the case of precise alignment may be approximately 5 μm. In millimeter-wave designs, an example of the diameter or width of the antenna element 120 is in the range of 1 to 2 mm, and the spacing between elements is in the range of approximately 2 to 4 mm in both the X and Y directions. Each RFIC110 can have a length and width in the range of approximately 4 to 6 mm. The thickness of the RFIC110 and the underfill layer 410 (height shown in Figure 4A) may be about 3 mm, and the thickness of the antenna substrate 150 may be about 10 mm.All dimensions above are illustrative to understand the typical small scale for millimeter-wave applications and may be modified by design and / or according to frequency and manufacturing precision.

[0022] Figure 4A also shows an example of a GSG connection in which grounding connections are made at two locations 317 on the opposite side of the connection to the signal line connection joint 420s described above. Each grounding connection is made by connecting the grounding pad 408 of the RFIC 110 to the grounding plane 340 at position 317 via the grounding connection joint 420g. The isolation layer 410 can consist of an underfill material surrounding each of the connection joints 420s and 420g to provide mechanical support to the connection joints 420s and 420g and thereby improve reliability. A typical underfill material may be a mixed material mainly composed of amorphous fused silica. In other embodiments, the underfill material is omitted, and the isolation layer 410 simply represents air. To insulate the via 302 from the grounding plane 340, a region of the grounding plane 340 surrounding the catch pad 406 is cut out to expose the lower surface 453 of the antenna substrate 150. This feature is best seen in Figure 4B, a cross-sectional view through the connection joints 420s, 420g as seen toward the substrate 150 (with the isolation layer 410 removed for clarity). Some examples of connection joints 420s and 420g are copper pillar connection joints, solder joints (e.g., formed from solder balls), and gold-gold bumping joints. As previously mentioned, an alternative embodiment may use a GS connection, which has only a single ground connection on one side of the signal connection. The GSG connection design offers more isolation and reduces stray light than the GS design, but is more complex. While some designs of the GSG connection may have three or more ground connection joints 420g, the actual implementation form has two connection joints 420g.

[0023] In Figure 4A and other figures herein, the antenna substrate 150 is shown as a single-layer substrate. In other embodiments, the antenna substrate 150 is a multilayer substrate having a patterned metal layer for providing several inter-chip RF routing between RFICs 110 and / or connections between DC lines on the RFICs 110. In this metal layer, the metal is removed in the area of ​​vias 302 to allow direct connection between the RFICs 110 and the antenna elements 120. Here, a single I / O pad 412 is shown in Figure 4A, but it should be further noted that in other embodiments, two or more I / O pads 412 are connected to each antenna element 120 as an alternative method for achieving circular polarization.

[0024] Figure 5 is a cross-sectional view of another exemplary connection structure 500 between the antenna element 120 and the RFIC 110. In this example, the feed point 122 is "substantially aligned" but not precisely aligned with the I / O port position 315 of the RFIC 110. (This can also be considered a subset of the "aligned" configuration, as previously mentioned.) For this purpose, a wider catch pad 506 extends beneath the via 302, which connects only to the first portion of the catch pad 506. The signal connection joints 520s extend beyond the first portion of the catch pad 506 and are beneath the second portion. Thus, the connection joints 520s are not directly beneath the via 302. This technique is advantageous when the process for forming the connection via 302 results in a non-planar bottom surface of the via 302 that can be translated parallel to the bottom surface of the catch pad. For example, in the configuration of Figure 4A, if the catch pad 406 has a non-planar bottom surface, the reliability of the connection joints 420s may be lower than desired. In Figure 5, via 302 may have a non-planar bottom on the lower right portion, but reliability is improved by replacing it with an extension catch pad 506 having a planar bottom on the left side. As a result, a more secure connection with the connecting joint 520s can be formed. In this case, the RFIC 110 includes an I / O pad 512 that is symmetrical with respect to the central axis 535. The central axis 425 of via 302 is horizontally offset by a distance d1 from axis 535, where a typical value of d1 may be approximately D (the diameter of via 302). Although there is an offset between the position of the feed point 122 and the I / O pad position 315, the offset is small, so the two positions are considered aligned. For example, with respect to wavelength, the maximum value of the offset d1 may be 0.02 wavelengths at the operating frequency of the antenna device 100, which may have a negligible electrical effect on antenna performance compared to the precisely aligned embodiment in Figure 4A.

[0025] Figure 6 shows a cross-sectional view of an exemplary detailed connection structure 600 between the antenna element 120 and the RFIC 110 within the antenna device 100. The illustrated connection structure 600 is an example of the connection structure 500 in Figure 5, and shows a closely aligned flip-chip connection in which via 302 is slightly offset horizontally from the center point 315 of the I / O pad 612 of the RFIC 110. Alternatively, via 302 may be precisely aligned with the I / O pad 612, in which case the configuration would be a detailed example of the connection structure 400 in Figure 4. The RFIC 110 may be a semiconductor die composed of III-V material for microwave and millimeter-wave designs, or silicon for lower frequencies. Some examples of III-V material include indium phosphide (InP), gallium arsenide (GaAs), silicon germanium (SiGe), and gallium nitride (GaN). The active die-side region 637 of the RFIC 110, for example, the upper region of the RFIC 110 above the virtual line 635, faces the antenna element 120. The active die-side region 637 may also include doping regions for transistors used in the beamforming circuit, such as low-noise amplifiers, power amplifiers, T / R switches, phase shifters, etc. The lower surface 631 may be plated with metal and used as ground for the internal circuitry of the RFIC 110.

[0026] Between the I / O pad 612 and the connection joint 520s, a surface finishing metal layer 624, such as electroless nickel-palladium immersion gold plating (ENEPIG), may be present to help the liquefiable metal (e.g., solder) of the connection joint 520s adhere to the I / O pad 612. The layer 624 may be formed in the general shape of an inverted frustocone with a central cavity on its upper surface to provide a more reliable connection interface. When a solder ball or other metal structure is placed during the flip-chip connection formation process, and then the top of layer 624 is liquefied, a portion of the liquid metal fills the upper cavity. This helps to form the connection joint 520s as a robust connection between the catch pad 506 and the I / O pad 612. In the example in Figure 6, the metal routing layer 616 functions as a rerouting layer for connecting circuit points within the RFIC 110 and / or between different RFICs 110. For this purpose, a first polymer overcoat layer 622, such as benzocyclobutene (BCB), may be formed between the upper surface of the RFIC 110 and the metal routing layer 616, and a second polymer overcoat layer 614 may be formed between the metal routing layer 616 and the isolation layer 410. Layers 622 and 614 provide isolation and support for the metal routing layer 616. The material of layer 622 may overlap the peripheral portion of the I / O pad 612 as shown in the figure. If the metal routing layer 616 is omitted, the first polymer overcoat layer 622 may still be present on the upper surface of the RFIC 110. The isolation layer 410 surrounds the connection joints 520s and extends between the overcoat layer 614 and the lower surface of the antenna substrate 150. A similar connection structure can be provided to connect the grounding pad 408 to the grounding plane 440 (neither of which are shown in Figure 6). In other words, each of the grounding pads 408 may be configured in the same way as the I / O pads 612, and the surface finishing metal layer 624 may be present between each grounding pad 408 and the corresponding connecting joint 520s, similar to the connecting joint 420g in Figure 6.

[0027] The flip-chip connection configuration in Figure 6 is sufficient to provide a short, aligned connection between the feed point 122 and the I / O pad 612, but it may exhibit the side effect of signal loss caused by interface the polymer overcoat layer 622 with the active die side of the RFIC 110. Another possible side effect stems from the proximity between the active die side region 637 and the antenna ground plane 440 (shown in Figure 4), which is located between the isolation layer 410 and the antenna substrate 150. This creates a risk of oscillation due to reflections between the ground plane 440 and the circuitry within the active die side region 637.

[0028] Figure 7A is a cross-sectional view of an exemplary dual via connection structure 700 between the antenna element 120 and the RFIC 110 in the antenna device 100. (The connection structure 700 is shown rotated 180° compared to that in Figures 3 to 6.) The connection structure 700 differs from the structure 600 in Figure 6 in that the active die side of the RFIC 110 does not have an interface with the polymer layer, thereby avoiding losses that would otherwise result from such an interface. Furthermore, because the antenna ground plane and the active die side region of the RFIC 110 are not further separated and facing each other, oscillation due to reflections between these regions is less likely to occur.

[0029] The RFIC 110 in Figure 7A has an active die-side region 737 above the virtual line 735. A first via 732 formed through the die of the RFIC 110 is electrically connected to a conductive trace 724 in a local region of the active die-side region 737. The local region may be a conductive I / O node of the beamforming circuit within the RFIC 110, and the conductive trace 724 may be connected to another circuit point of the beamforming circuit. The first via 732 may be called a "hot via" because it is not electrically connected to ground. At its opposite end, the first via 732 connects to an I / O pad 712 located on the underside of the RFIC 110, opposite the active die-side region 737. The I / O pad 712 connects to the antenna element 120 at the feed point 122 via a series of conductors. These may include copper pillars 752 or gold / solder bumps, solder caps 754 (or other liquefiable metal caps), a surface finishing metal layer 756 such as ENEPIG, catch pads 706, and second vias 702 formed through the antenna substrate 150. Signal connection joints 720s include copper pillars 752 and solder caps 754, the copper pillars 752 may be formed by growing copper into pillars, and the solder caps 754 are applied to generate the signal connection joints 720s as solder connections. Catch pads 706 are formed on the rear surface 453 of the substrate 150 and may be similar to catch pads 506 in Figure 5. A passivation layer 760, such as a quartz polymer layer, may surround the surface finishing metal layer 756 and may be formed partially on the substrate surface 453 and partially on the exposed surface of the catch pads 706. As illustrated below in the example of Figure 7B, one or more passivation layers 760 can act as an insulator between the ground plane 440 and one or more redistribution metal layers between the substrate 150 and the RFIC 110.

[0030] For example, when via 702 is formed, a non-planar surface may be created near surface 453 of the substrate 150, which may be translated parallel to the adjacent area of ​​catch pad 706. Thus, catch pad 706 can be designed to extend horizontally as shown in the figure, so that the connection joint area (layers 756, 754, and 752) to the RFIC 110 can have greater strength and reliability. The same applies to via 732 and catch pad 712. Since the horizontal extensions of catch pads 706 and 712 may be similar, the feed point 122 can be substantially or precisely aligned with the position 315 of the I / O pad 712 (i.e., aligned as previously defined). Furthermore, even if catch pads 706 and 712 are not designed to extend in the same direction, the offset between the central axis of each via 702, 732 and the connection joint 720s is small (e.g., less than 0.02 wavelengths), so the I / O pad position 315 and the antenna feed point 122 are still aligned.

[0031] The isolation layer 410 (with or without underfill material) may be positioned between the passivation layer 760 and the bottom surface 631 of the RFIC 110. If the isolation layer 410 consists of underfill, the underfill does not form an interface with the active die region 737 of the RFIC 110, thus avoiding signal loss that would otherwise be caused by the interface. In addition, the possibility of oscillation is reduced compared to the connection structure 600 in Figure 6. This is because the active die region 737 is located further away from the ground plane 440 (located between the surface 453 of the substrate 150 and the isolation layer 410, as seen in Figures 4A, 4B, 5 and 7B, although not shown in Figure 7). Furthermore, a grounding surface acting as ground for the beamforming circuit within the RFIC 110 can be present on the bottom surface 631 of the RFIC 110, further reducing the risk of oscillation.

[0032] Figure 7B is a cross-sectional view of an exemplary portion of the antenna device 100 showing an exemplary extended connection structure encompassing the dual via connection of Figure 7A. The connection structure 700a includes the connection structure 700 described above, with first and second ground connection joints 720g1 and 720g2 on both sides, collectively forming a GSG connection set 720. Each of the ground connection joints 720g1 and 720g2 may have the same type of structure and similar dimensions as the signal connection joints 720s. Each of the ground connection joints 720g1 and 720g2 can electrically connect their respective local areas of the ground surface 708 of the RFIC 110 to connection points on the ground plane 440. A local surface finishing layer 756 may be applied to the ground plane 440 to help the ground connection joints 720g1 and 720g2 adhere to the ground plane 440.

[0033] Figure 7B also shows a redistribution layer (RDL) 788 that may exist between the RFIC 110 and the ground plane 440. The redistribution layer 788 may be used to connect circuit points within the RFIC 110 and / or circuit points of different RFIC 110s, typically to route DC bias between circuit points. The RDL 788 is formed over the area of ​​the protective layer 760, separating the protective layer from the ground plane 440. A connection joint 790, which may have the same type of structure as the signal connection joints 720s, can connect the I / O pads 792 of the RFIC 110 to the RDL 788. The RDL 788 extends horizontally and can be connected via another connection joint 790 to another I / O pad of the RFIC 110 (not shown) or a different RFIC 110 to route signal / DC voltages between different circuit points of the RFIC(s) 110. If at least one additional RDL 788 is added to the configuration of the antenna device 100, an additional passivation layer 760 may be placed on one or both sides of each additional RDL to provide the necessary isolation between the RDLs.

[0034] Figure 8A shows an exemplary arrangement 800a of antenna element feed point positions for an RFIC connected within the antenna device 100. In this example, the RFIC 110 is connected to four antenna elements 120-a, 120-b, 120-c, and 120-d, which are arranged as part of a triangular grid with respect to the center point 123 of the antenna elements. The center point 123 may also be referred to herein as the phase center 123 of each antenna element. The RFIC 110 is arranged as part of a rectangular grid, as previously shown in Figures 1 and 2. Each of the antenna elements 120-a to 120-d is exemplified as a circular patch element having a slit 811 (elongated slot) extending from an open end on the periphery of the antenna element to a closed end toward the center point 123. The antenna elements 120-a to 120-d are connected to the RFIC 110 from feed points 122-a, 122-b, 122-c, and 122-d, respectively. Please note that the "×" inside the "○" indicating power supply point 122 represents one of the I / O pads of the RFIC110, such as I / O pads 412, 512, 624, or 712 mentioned above.

[0035] Instead of feeding each antenna element 120 at its center point 123, the feed points 122-a to 122-d in each group of four antenna elements connected to the RFIC 110 are offset in different directions from the center point 123, and the slits 811 are aligned corresponding to different directions. The patch design may be the same for each of the four antenna elements 120-a to 120-d, or it may be rotated in 90-degree increments between the antenna elements. This rotation in the patch design from antenna elements 122-a to 122-d advantageously forms circular polarization with pattern diversity and a low axial ratio. The position and dimensions of each slit 811, as well as the relative positions of adjacent feed points 122, are designed to form circular polarization with respect to the corresponding antenna element 120. For this purpose, the length of each slit 811 may range from 1 / 4 to 3 / 4 of the radius of the antenna element 120. In one example, each slit 811 is approximately 2 / 3 of the radius. The power supply points 122-a to 122-d are each offset laterally from the side of the adjacent slit 811 that is closest to the closed end.

[0036] The local coordinate system of the RFIC110, which has a rectangular footprint, can be defined by the origin at the center point 113, with an X-axis parallel to the top and bottom edges of the rectangular footprint, and a Y-axis parallel to the left and right edges. The local coordinate system of each antenna element 120-a to 120-d can also be defined by the origin at the center point 123, with an x-axis parallel to the X-axis and a y-axis parallel to the Y-axis. Antenna elements 120-a and 120-b have the same +X coordinate at the center point 123 and are positioned in the upper row, spaced X1 apart in the column direction. Antenna elements 120-c and 120-d are in the lower row at the same -Y level, separated X1 in the column direction and spaced Y1 apart from the upper row. The slits 811 and corresponding feed points 122-a to 122-d of antenna elements 120-a to 120-d are rotated by 90°. Therefore, feed points 122-a, 122-b, 122-c, and 122-d are each located in different quadrants of the local xy coordinate system. In this example, feed points 122-a to 122-d are in the lower left (-x, -y), upper left (+y, -x), upper right (+x, +y), and lower right (+x, -y) quadrants, respectively. Each feed point 122 is offset by Δx and Δy in the x and y directions from its respective center point 123. In the y direction, in each column, the feed point has a y-axis variation of 2Δy. In the x direction, there is an inter-column variation of 2Δx compared to supplying all antenna elements to the center point 123.

[0037] In the arrangement shown in Figure 8A, the rotation of the patch design, which causes variation in the position of the feed point 122 from quadrant to quadrant relative to the center 123 of the antenna element 120, improves the axial ratio and pattern diversity. However, because the feed point of each row varies in the y-direction, the layout of the beamforming circuit within the RFIC 110 is asymmetrical, making circuit layout and packaging more complex and difficult.

[0038] Figure 8B shows another exemplary arrangement 800b of antenna element feed point positions relative to the RFIC 110 connected within the antenna device 100. This differs from arrangement 800a in that the feed points 122 in each row have the same Y coordinate, which allows for a simpler beamforming circuit layout. Similar to arrangement 800a, the RFIC 110 is connected to four antenna elements 120-a, 120-b, 120-c and 120-d, which for comparison can be assumed to have the same footprint and relative positions as in Figure 8A. Each feed point 122 is also shown to be offset by Δx and Δy from the adjacent center point 123. However, in device 800b, in the top row, feed point 122-a is in the upper left quadrant and feed point 122-b is in the upper right quadrant. Thus, the X spacing between these feed points is (X1 + 2Δx), which is 2Δx wider than that of arrangement 800a. Similarly, in the lower row, feed point 122-c is in the lower left quadrant, and feed point 122-d is in the lower right quadrant, and the X-distance between these feed points is also (X1 + 2Δx). Furthermore, in the Y direction, the spacing between feed points 122 in the upper and lower rows is uniform (Y1 + 2Δy). Note that the position of the slit 811 relative to the quadrant position of feed point 122 is the same as in arrangement 800a.

[0039] Therefore, for a given RFIC 110 having I / O pad positions according to configuration 800b, the I / O pad positions (corresponding to the feed point 122 positions) are further apart in both the X and Y directions compared to the distance between the center points 123. This is also true for configuration 800a when considering the maximum X and Y distance between any two feed points 122. Thus, assuming the same beamforming circuit in the RFIC 110 for configurations 800b and 800a, the same rectangular footprint of the RFIC 110 can be typical.

[0040] Figure 8C shows yet another exemplary arrangement 800c of the antenna element feed point positions relative to the RFIC 110 connected within the antenna device 100. In this embodiment, the same relative positions of antenna elements 120-a to 120-d, i.e., the spacing of antenna elements 120 within a row X1 and the spacing between rows Y1, can be assumed. However, in configuration 800c, the feed points 122-a, 122-b, 122-c, and 122-d are located in the lower right, lower left, upper right, and upper left quadrants, respectively. This reduces the X spacing (X1-2Δx) between the feed points 122-a and 122-b in the top row, and between the feed points 122-c and 122-d in the bottom row. Furthermore, the Y spacing between rows of feed points 122 is also reduced to (Y1-2Δy). Therefore, in configuration 800c, the corresponding I / O pads (where "x" in feed point 122 represents one of the I / O pads 412, 512, etc.) can use a smaller rectangular footprint of the RFIC110, provided that the packaging of the beamforming components allows.

[0041] Accordingly, embodiments of configurations 800a, 800b, and 800c can be summarized as follows: Each of the RFIC 110 includes a plurality of N I / O pads connected to a plurality of corresponding feed points of a group of N circularly polarized antenna elements. The first antenna element of a group has at least one feed point offset in a first direction from its center point, and the second antenna element of a group has at least one feed point offset in a second different direction from its center point, the first and second directions being defined with respect to a common coordinate system. Each group may be a group of four antenna elements connected to a single RFIC. If there are four antenna elements in each group, each of the four antenna elements has a feed point offset from the center of the respective antenna element in a direction different from any of the other antenna elements of the four antenna elements with respect to a common coordinate system. Each of the antenna elements of a group may have the same design configuration having a slit and at least one feed point laterally offset from the edge of the slit to generate circular polarization for transmit and / or receive operations. Each of the second to fourth antenna elements of the group of four can be rotated by K × 90° relative to the first antenna element of the group, where K is in the range of 1 to 3 and is different for each of the second to fourth antenna elements.

[0042] Figure 9 shows an exemplary layout of a beamforming circuit within an RFIC 110 having I / O pads arranged according to arrangement 800b of Figure 8B. In this example, the RFIC 110 has four GSG I / O pad connection sets ("GSG sets") 940-a, 940-b, 940-c, and 940-d, each having a signal I / O pad ("S pad") 912 and a pair of ground ("G") pads 408 on either side of the S pad 912. Thus, each of the GSG sets 940-a to 940-d can be a set of linearly aligned first and second ground pads, as well as signal pads that collectively form an elliptical profile having a major axis and a perpendicular minor axis, where the major axis is substantially parallel to the left and right edges of each RFIC 110.

[0043] Each S pad 912 may be configured as one of the I / O pads 412, 512, 624, or 712 described above, and each G pad 408 may be configured as one of the G pads 408 shown in Figure 4. Each S pad 912 is connected to the corresponding power supply points 122-a to 122-d using one of the connection structures described above for the I / O pads 412, 512, etc. Thus, each S pad 912 is aligned with each of the power supply points 122-a, 122-b, 122-c, and 122-d. In each GSG set 940-a to 940-d, the G pads 408 and S pads 912 may be linearly aligned in the Y direction.

[0044] The first output amplifier region 920-1 may be located between GSG sets 940-a and 940-b, and the second output amplifier region 920-2 may be located between GSG sets 940-c and 940-d. Each GSG set 940-a to 940-d can be connected to the output or input of the respective amplifier 903 in the adjacent amplifier region 920-1 or 920-2. In the illustrated example, amplifier 903 is a power amplifier during transmission, and each GSG set is connected to the output port of amplifier 903. In other examples, some of the amplifiers 903 are PAs and others are LNAs. In the latter case, any given GSG set 940 can be connected to the input of the LNA.

[0045] Circuit region 950 having additional beamforming circuits may be located outside regions 920-1 and 920-2. For example, each amplifier 903 may be connected to its respective bandpass filter 905 and phase shifter 907 within circuit region 950. Generally speaking, the amplifiers 903 work in conjunction with the beamforming circuits within circuit region 950 to adjust the input / output signals (e.g., amplification, phase shifting, filtering, etc.) from the GSG set 940 (received from antenna elements 120 / output to antenna elements). Circuit region 950 may further include at least one combiner / divider 910 consisting of one or more RF couplers (e.g., 3dB directional couplers) for combining and / or splitting the signals received / transmitted from at least two antenna elements 120.

[0046] GSG sets 940-a and 940-d are positioned close to the upper left and lower right corners of the RFIC 110, respectively. These positions may be set as close as possible to the left and right edges of the RFIC 110, respectively (as shown in Figure 9), as permitted by the design rules of the foundry manufacturing the RFIC 110. GSG sets 940-a and 940-b may be located close to the upper edge of the RFIC 110 and at the same Y level. GSG sets 940-c and 940-d may be located close to the lower edge and at the same Y level. GSG set 940-b may have an X-direction center coordinate approximately midway between GSG sets 940-c and 940-d. Similarly, GSG set 940-c may have an X-direction center coordinate approximately midway between GSG sets 940-a and 940-b. As described above, when each GSG set 940 is aligned with the corresponding feed point 122 of the antenna element 120, the position of the GSG set 940 is aligned with the triangular grid point 123 of the antenna element 120, as shown in Figure 2. This configuration differs from a typical RFIC chip, which typically has all I / O pads arranged symmetrically adjacent to the opposing edges of their rectangular footprint. For example, in a typical RFIC chip, GSG set 940-c is located in the lower left corner, and GSG set 940-b is located in the upper right corner. The arrangement in Figure 9, which moves some of the GSG sets inward from the corners, allows for alignment between the GSG sets and the antenna feed point 122.

[0047] While the technologies described herein are shown and explained in particular with reference to exemplary embodiments, it will be understood by those skilled in the art that various modifications of form and detail can be made without departing from the spirit and scope of the subject matter set forth in the following claims and their equivalents.

Claims

1. An antenna device, A first component layer comprising a plurality of radio frequency integrated circuit chips (RFICs) arranged in a first plane having a first grid arrangement, wherein each RFIC includes a beamforming circuit, and the first component layer comprises A second component layer superimposed on the first component layer and having a second different grid arrangement, comprising a plurality of antenna elements arranged in a second plane parallel to the first plane, wherein the first and second grid arrangements are different two-dimensional arrangements, and each antenna element has a feed point connected to an input / output (I / O) pad of an RFIC, and each I / O pad is connected to and aligned with the feed point along an axis perpendicular to the first and second planes, An antenna device comprising a substrate between the first component layer and the second component layer, and a plurality of vias extending through the substrate, wherein each of the vias connects one of the antenna elements to one of the plurality of I / O pads of the RFIC, and each of the active die sides of the RFIC faces the opposite side of the substrate and the second component layer.

2. The antenna device according to claim 1, wherein the first grid arrangement is rectangular and the second grid arrangement is triangular.

3. The antenna device according to claim 1, wherein the plurality of I / O pads are flip-chip I / O pads, and each flip-chip I / O pad is electrically connected to one of the vias via a flip-chip electrical connection joint.

4. The flip-chip electrical connection joint is surrounded by an underfill layer between the substrate and the second component layer. The antenna device according to claim 3, further comprising a polymer overcoat layer between the second constituent layer and the underfill layer.

5. The aforementioned plurality of vias are a plurality of first vias, The aforementioned antenna device is Each of the following is a plurality of second vias that extend from the inactive side of the RFIC to the active side of the RFIC, The antenna device according to claim 1, further comprising a plurality of electrical connection joints, each connecting the end of a first via to the end of a second via.

6. The antenna device according to claim 5, wherein each of the plurality of electrical connection joints is surrounded by an underfill layer between the substrate and the second component layer.

7. The antenna device according to claim 1, wherein each of the RFICs includes a plurality of N I / O pads connected to a plurality of corresponding feed points of the N antenna elements, and the antenna device lacks any transmission lines oriented parallel to the first and second planes for coupling any RFIC in the first component layer to any antenna element in the second component layer.

8. Each of the RFICs includes a plurality of N I / O pads connected to the corresponding plurality of feed points of the N antenna elements, Each of the aforementioned antenna elements is a circularly polarized patch antenna element. The antenna device according to claim 1, wherein a first antenna element among the plurality of antenna elements has at least one feed point offset in a first direction from the center of the first antenna element, and a second antenna element among the plurality of antenna elements has at least one feed point offset in a second direction different from the first direction from the center of the second antenna element, and the first and second directions are defined with respect to a common coordinate system.

9. The antenna device according to claim 1, wherein the antenna elements are arranged in a group of four antenna elements connected to a single RFIC, and in each of the group, each of the four antenna elements has a feed point offset from the center of the respective antenna element in a direction different from any of the other antenna elements of the four antenna elements with respect to a common coordinate system.

10. Each of the antenna elements in the group has the same design configuration, comprising a slit and at least one feed point laterally offset from the edge of the slit to generate circular polarization for transmission and / or reception operations. The antenna device according to claim 9, wherein each of the second to fourth antenna elements of the group of four antenna elements is rotated by K × 90° with respect to the first antenna element of the group, where K is in the range of 1 to 3 and is different for each of the second to fourth antenna elements.

11. The antenna device according to claim 1, further comprising a ground plane between the first constituent layer and the second constituent layer.

12. The first grid arrangement is rectangular, the second grid arrangement is triangular, and the antenna device is An antenna substrate located between the first constituent layer and the second constituent layer, A plurality of vias extending through the antenna substrate, each of which comprises a plurality of vias connecting the feed point of one of the antenna elements to one of the I / O pads, The antenna device according to claim 1, wherein the antenna elements are arranged in groups of N antenna elements connected to a single RFIC, and in each group, each of the N antenna elements has a feed point offset from the center of its own antenna element in a direction different from the feed point offset direction of any of the other antenna elements among the N antenna elements with respect to a common coordinate system.

13. The antenna device according to claim 12, wherein N is equal to 4.

14. The antenna device according to claim 12, further comprising a ground plane between the antenna substrate and the second component layer.

15. The antenna device according to claim 12, further comprising a ground plane between the antenna substrate and the second component layer, wherein each RFIC includes first, second, third, and fourth ground-signal-ground I / O pad connection sets ("GSG sets"), the signal I / O pads of each GSG set are connected to the feed points of the respective antenna elements, and the first and second ground pads of each GSG set are each connected to the ground plane.

16. Each RFIC has a rectangular profile with an upper edge, a lower edge, a left edge, and a right edge, the X direction is parallel to the upper and lower edges, and the Y direction is parallel to the left and right edges. The first GSG set is positioned in the upper left corner of each RFIC, and the fourth GSG set is positioned in the lower right corner of each RFIC. The second GSG set has a Y coordinate close to the upper edge and an X coordinate approximately midway between the X coordinates of the third GSG set and the fourth GSG set. The antenna device according to claim 15, wherein the third GSG set has a Y coordinate close to the lower edge and an X coordinate approximately midway between the X coordinates of the first GSG set, the second GSG set, and the fourth GSG set.

17. The antenna device according to claim 16, wherein each of the GSG sets is a linearly aligned set of first and second grounding pads and signal pads that collectively form a rectangular profile having a major axis and a perpendicular minor axis, the major axis being substantially parallel to the left and right edges of the respective RFIC.

18. The antenna device according to claim 12, wherein the beamforming circuit is a millimeter-wave front-end circuit.

19. An antenna device, A first component layer comprising a plurality of radio frequency integrated circuit chips (RFICs) arranged in a first plane having a first grid arrangement, wherein each RFIC includes a beamforming circuit, and the first component layer comprises An antenna device comprising: a second component layer superimposed on the first component layer and having a second grid arrangement, comprising a plurality of antenna elements arranged in a second plane parallel to the first plane, wherein each of the first and second grid arrangements is a two-dimensional arrangement, and each of the antenna elements has a feed point connected to an input / output (I / O) pad of an RFIC, and each I / O pad is connected to and aligned with the feed point along an axis perpendicular to the first and second planes.

20. An antenna device, A first component layer comprising a plurality of radio frequency integrated circuit chips (RFICs) arranged in a first plane having a first grid arrangement, wherein each RFIC includes a beamforming circuit, and the first component layer comprises A second component layer is superimposed on the first component layer and includes a plurality of antenna elements arranged in a second plane parallel to the first plane, having a second grid arrangement, wherein each of the first and second grid arrangements is a two-dimensional arrangement, and each of the antenna elements has a feed point connected to an input / output (I / O) pad of an RFIC, and each I / O pad is connected to and aligned with the feed point along an axis perpendicular to the first and second planes. Each of the RFICs includes a plurality of N I / O pads connected to a plurality of corresponding feed points of the N antenna elements, Each of the aforementioned antenna elements is a circularly polarized patch antenna element. An antenna device in which a first antenna element among the plurality of antenna elements has at least one feed point offset in a first direction from the center of the first antenna element, and a second antenna element among the plurality of antenna elements has at least one feed point offset in a second direction different from the first direction from the center of the second antenna element, and the first and second directions are defined with respect to a common coordinate system.

21. An antenna device, A first component layer comprising a plurality of radio frequency integrated circuit chips (RFICs) arranged in a first plane having a first grid arrangement, wherein each RFIC includes a beamforming circuit, and the first component layer comprises A second component layer is superimposed on the first component layer and includes a plurality of antenna elements arranged in a second plane parallel to the first plane, having a second grid arrangement, wherein each of the first and second grid arrangements is a two-dimensional arrangement, and each of the antenna elements has a feed point connected to an input / output (I / O) pad of an RFIC, and each I / O pad is connected to and aligned with the feed point along an axis perpendicular to the first and second planes. The antenna device according to claim 1, wherein the antenna elements are arranged in a group of four antenna elements connected to a single RFIC, and in each of the group, each of the four antenna elements has a feed point offset from the center of its own antenna element in a direction different from any of the other antenna elements of the four antenna elements with respect to a common coordinate system.

22. An antenna device, A first component layer comprising a plurality of radio frequency integrated circuit chips (RFICs) arranged in a first plane having a first grid arrangement, wherein each RFIC includes a beamforming circuit, and the first component layer comprises A second component layer superimposed on the first component layer and having a second grid arrangement, comprising a plurality of antenna elements arranged in a second plane parallel to the first plane, wherein each of the first and second grid arrangements is a two-dimensional arrangement, and each of the antenna elements has a feed point connected to an input / output (I / O) pad of an RFIC, and each I / O pad is connected to and aligned with the feed point along an axis perpendicular to the first and second planes, An antenna substrate located between the first constituent layer and the second constituent layer, A plurality of vias extending through the antenna substrate, each of which comprises a plurality of vias connecting the feed point of one of the antenna elements to one of the I / O pads, The antenna device is configured such that the antenna elements are arranged in groups of N antenna elements connected to a single RFIC, and in each group, each of the N antenna elements has a feed point offset from the center of the respective antenna element in a direction different from the feed point offset direction of any of the other antenna elements among the N antenna elements, with respect to a common coordinate system.

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