Antenna structure and antenna packaging

Abstract

The present invention discloses an antenna structure, comprising: a radiating antenna element, arranged in a first conductive layer; and a reference ground plane, arranged in a second conductive layer below the first conductive layer, wherein the radiating antenna element is loaded with a plurality of slots, and the radiating antenna element is electrically connected to the reference ground plane through a plurality of through holes, and wherein the plurality of through holes are placed along a first line of the radiating antenna element, and the plurality of slots are placed along a second line perpendicular to the first line. The present invention can be used to suppress any even-order TM mode excited in the entire structure, and maintain a stable broadside radiation pattern over the entire operating frequency band, and can also obtain a gradual taper of the amplitude in the radiation pattern, thereby providing a low sidelobe level within a wide bandwidth range.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor technology, and in particular to an antenna structure and an antenna package. Background Art

[0002] Conventional millimeter wave (mm-wave) fan-beam high-gain antennas consist of linear, series-fed patch antennas. They are used to achieve low side lobe beams by controlling the feed network of the fed patch antenna and the size of each patch element. However, the beam tilts with frequency, resulting in varying gain across the frequency band.

[0003] As is also known in the art, a grid array antenna (GAA) structure is typically composed of a rectangular grid of microstrip lines on a dielectric substrate supported by a metal ground plane, and fed by metal vias passing through apertures (apertures, or small holes or slots) in the ground plane. Depending on the electrical length of the grid sides, the grid array antenna can be resonant or non-resonant.

[0004] However, conventional grid array antennas do not perform well at millimeter wave frequencies (eg, 77-89 GHz). Therefore, there is a need to provide an improved antenna structure having high gain and a desired fan-beam radiation pattern or field shape at millimeter wave frequencies. Summary of the invention

[0005] In view of this, the present invention provides an antenna structure and an antenna package to solve the above problems.

[0006] According to a first aspect of the present invention, an antenna structure is disclosed, comprising:

[0007] a radiating antenna element disposed in the first conductive layer; and

[0008] A reference ground plane is disposed in a second conductive layer below the first conductive layer,

[0009] wherein the radiating antenna element is loaded with a plurality of slots, and the radiating antenna element is electrically connected to a reference ground plane through a plurality of through holes, and

[0010] The through hole is placed along a first line of the radiating antenna element, and the slot is placed along a second line perpendicular to the first line.

[0011] According to a second aspect of the present invention, an antenna structure is disclosed, comprising:

[0012] a radiating antenna element disposed in the first conductive layer;

[0013] a reference ground plane disposed in a second conductive layer below the first conductive layer; and a feeding network comprising a pair of transmission lines disposed in a third conductive layer below the second conductive layer, and a pair of differential feeding terminals, wherein the pair of differential feeding terminals are configured to electrically couple one end of the pair of transmission lines to the radiating antenna element, and

[0014] The radiating antenna element is loaded with a plurality of slots and the radiating antenna element is electrically connected to the reference ground plane through a plurality of the through holes.

[0015] According to a third aspect of the present invention, an antenna package is disclosed, comprising:

[0016] A radiating antenna element disposed in a first conductive layer; a reference ground plane disposed in a second conductive layer below the first conductive layer, wherein the radiating antenna element carries a plurality of slots and the radiating antenna element is electrically connected to the reference ground plane through a plurality of through holes; and a feeding network comprising a pair of transmission lines disposed in a third conductive layer below the second conductive layer, and a pair of differential feeding ends, wherein the pair of differential feeding ends are used to electrically couple one end of the pair of transmission lines to the radiating antenna element; and

[0017] The semiconductor chip is electrically coupled to the antenna structure through the feeding network.

[0018] The antenna structure of the present invention comprises: a radiating antenna element arranged in a first conductive layer; and a reference ground plane arranged in a second conductive layer below the first conductive layer, wherein the radiating antenna element is loaded with a plurality of slots, and the radiating antenna element is electrically connected to the reference ground plane through a plurality of through holes, and wherein the through holes are placed along a first line of the radiating antenna element, and the slots are placed along a second line perpendicular to the first line. The present invention can be used to suppress any even-order TM mode excited in the entire structure, and maintain a stable broadside radiation pattern over the entire operating frequency band, and can also obtain a gradual taper of the amplitude in the radiation pattern, thereby providing a low sidelobe level within a wide bandwidth range. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 FIG. 1 is a schematic diagram of an antenna structure according to an embodiment of the present invention.

[0020] Figure 2 FIG. 1 is an XZ plane diagram and an electric field diagram of an antenna structure according to an embodiment of the present invention.

[0021] Figure 3 FIG. 4 is a cross-sectional schematic diagram of an antenna structure according to an embodiment of the present invention.

[0022] Figure 4FIG. 4 is another cross-sectional schematic diagram of an antenna structure according to an embodiment of the present invention.

[0023] Figure 5 is a schematic top view of an antenna structure proposed according to an embodiment of the present invention.

[0024] Figure 6 is a schematic top view of an antenna structure proposed according to another embodiment of the present invention.

[0025] Figure 7 is a schematic cross-sectional view showing an exemplary antenna package having a proposed antenna structure according to one embodiment of the present invention.

[0026] Figure 8 is a schematic diagram showing a radiation pattern of an antenna structure proposed in an electric-plane (E-plane) according to an embodiment of the present invention.

[0027] Fig. 9 is a schematic diagram showing a radiation pattern of an antenna structure proposed in a magnetic-plane (H-plane) according to an embodiment of the present invention.

[0028] Fig.10 is a schematic diagram illustrating different shapes of radiating antenna elements implemented in an antenna structure according to an embodiment of the present invention. DETAILED DESCRIPTION

[0029] In the following detailed description of the embodiments of the invention, reference is made to the accompanying drawings, which form a part of the present invention and in which are shown by way of illustration certain preferred embodiments in which the invention may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice them, and it is understood that other embodiments may be utilized and mechanical, structural and procedural changes may be made without departing from the spirit and scope of the invention. Therefore, the following detailed description should not be construed as limiting, and the scope of the embodiments of the invention is limited only by the appended claims.

[0030] It will be understood that although the terms "first," "second," "third," "primary," "secondary," etc. may be used herein to describe various elements, components, regions, layers, and / or portions, these elements, components, regions, layers, and / or portions should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer, or portion from another region, layer, or portion. Thus, a first or primary element, component, region, layer, or portion discussed below may be referred to as a second or secondary element, component, region, layer, or portion without departing from the teachings of the present inventive concept.

[0031] In addition, for ease of description, spatially relative terms such as "below," "under," "under," "above," and "over" may be used herein to describe the relationship of an element or feature to another element or feature as shown. In addition to the orientations described in the figures, the spatially relative terms are intended to cover different orientations of the device in use or operation. The device can be oriented in other ways (rotated 90 degrees or in other orientations), and the spatially relative descriptors used herein can likewise be interpreted accordingly. In addition, it will also be understood that when a layer is referred to as being "between" two layers, it can be the only layer between the two layers, or one or more intermediate layers can also be present.

[0032] The terms "approximately", "roughly" and "about" generally mean within the range of ±20% of a specified value, or ±10% of the specified value, or ±5% of the specified value, or ±3% of the specified value, or ±2% of the specified value, or ±1% of the specified value, or ±0.5% of the specified value. The specified values ​​of the present invention are approximate values. When not specifically described, the specified values ​​include the meanings of "approximately", "roughly" and "about". The terms used herein are for the purpose of describing specific embodiments only and are not intended to limit the present invention. As used herein, the singular terms "one", "an" and "the" are also intended to include plural forms, unless the context clearly indicates otherwise. The terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the inventive concept. As used herein, the singular forms "one", "a kind of" and "the" are also intended to include plural forms, unless the context clearly indicates otherwise.

[0033] It will be understood that when an element or layer is referred to as being “on,” “connected to,” “coupled to,” or “adjacent to” another element or layer, it can be directly on, connected to, coupled to, or adjacent to the other element or layer, or intervening elements or layers may be present. In contrast, when an element is referred to as being “directly on,” “directly connected to,” “directly coupled to,” or “immediately adjacent to” another element or layer, there are no intervening elements or layers present.

[0034] Note that: (i) like features will be indicated by like reference numerals throughout the figures and will not necessarily be described in detail in each figure in which they appear, and (ii) a series of figures may show different aspects of a single item, each aspect being associated with various reference labels which may appear throughout the sequence or may only appear in selected figures of the sequence.

[0035] The present invention relates to an antenna structure with high gain and fan-shaped beam and an antenna package (antenna-in-package, AiP) having such an antenna structure. Some suitable packaging types may include, but are not limited to, fan-out wafer level package (fan-out wafer level package, FOWLP), flip-chip chip-scale package (flip-chip chip-scale package, FCCSP) or semiconductor embedded in substrate (semiconductor-embedded in substrate, SESUB). In addition, the present invention may be applicable to antenna-on-board (AOB) applications. The disclosed antenna structure is applicable to radar sensors for automotive applications or 5G mobile communication systems, but is not limited thereto.

[0036] Figure 1 Schematic diagram of the antenna structure of an embodiment of the present invention. The antenna structure 100 may include a radiating antenna element 110 and a reference ground plane 120. The radiating antenna element 110 is disposed in a first conductive layer. The reference ground plane 120 is disposed in a second conductive layer below the first conductive layer. According to an embodiment of the present invention, the radiating antenna element 110 is an electrically long or electrically long (several wavelengths) patch antenna operating in a transverse magnetic field (TM4n+1,0) mode and the radiating antenna element 110 includes a plurality of etched slots, such as slots (or slots, slits, etc.) SL-1 to SL-(2*n). For example, but not limited to, in Figure 1 In the illustrated embodiment, the radiating antenna element 110 operates in TM13,0 mode and is loaded with six slots SL-1 to SL-6, where n = 3. It should be noted that the number of slots etched on the radiating antenna element is not limited to six, but may also be 4, 5, 8, 10, etc. The slots penetrate the radiating antenna element 110 .

[0037] According to an embodiment of the present invention, in addition to etching a plurality of grooves on the radiating antenna element 110, the antenna structure 100 may further include a plurality of through holes 33. The through holes (or perforations, holes) 33 may serve as short-circuit through holes and the radiating antenna element 110 is electrically connected to the reference ground plane 120 through the through holes 33. It should also be noted that although Figure 1 Six through holes 33 are shown in FIG. 1 , but the number of through holes is not limited to six, and may be 1, 2, 4, 5, 8, 10, etc. The through holes 33 may also be referred to as conductive through holes.

[0038] According to one embodiment of the present invention, the through hole 33 is placed along a first line of the radiating antenna element 110, and the slots SL-1 to SL-(2*n) are placed along a second line perpendicular to the first line. In one embodiment of the present invention, the first line is the center line of the patch antenna (i.e., the radiating antenna element 110). Specifically, the first line is the center line of the radiating antenna element 110 along its width, and the first line extends along the Y-axis, parallel to the wide side of the radiating antenna element 110, and perpendicular to the long side of the radiating antenna element 110. After being divided by the first line, the portions of the radiating antenna element 110 on both sides of the first line may be axially symmetrical, with the first line being the axis of symmetry. In addition, the number of slots on the radiating antenna element 110 may also be equal on both sides with the first line being the axis of symmetry. As shown in FIG. Figure 1 As shown, the track of the through hole 33 is placed along the center of the radiating antenna element 110, wherein the center line (or the first line) of the radiating antenna element 110 is a virtual line passing through the center point of the radiating antenna element 110, and the second line of the radiating antenna element 110 is also a virtual line extending along the X-axis. The first line passes through the center of the radiating antenna element 110 and extends along a first direction (e.g., the Y-axis direction) (or it can also be said that the first line passes through the center of the radiating antenna element 110 and extends in a direction parallel to the width of the radiating antenna element 110), and the second line extends in a second direction (e.g., the X-axis direction), and the second direction is perpendicular to the first direction. The length direction of the slot on the radiating antenna element 110 extends along the Y-axis direction, and is arranged in parallel and uniformly along the direction of the X-axis. The direction in which the multiple through holes 33 extend after being arranged is the same as the length direction of the slot, and extends along the Y-axis direction.

[0039] According to one embodiment of the present invention, Figure 1 As shown, 2*n grooves are evenly distributed or substantially evenly distributed on both sides of the through hole 33. That is, there may be n grooves on each side of the through hole 33.

[0040] According to one embodiment of the present invention, the antenna structure 100 may further include a feeding network. The feeding network may include a pair of transmission lines disposed in a third conductive layer below the second conductive layer, and a pair of differential feeding terminals. Figure 1 As shown, the feeding terminals 35 - 1 and 35 - 2 are distributed on both sides of the through hole 33 , and at least part of the transmission lines TL- 1 and TL- 2 are respectively routed on both sides of the through hole 33 .

[0041] In an embodiment of the present invention, the antenna structure 100 can be configured to operate with a predetermined radio frequency (RF) signal having an RF frequency and a corresponding wavelength (e.g., a guide wavelength λg). According to one embodiment of the present invention, the distance between adjacent slots (e.g., the distance from the center of one slot to the center of an adjacent slot) can be designed to be equal to or substantially equal to λg, and the length of at least one slot is equal to or substantially equal to λg / 2. In an embodiment of the present invention, by controlling the shape of the radiating antenna element 110 and the slot, a gradual taper of the amplitude of the radiation pattern can be obtained, thereby providing a low side lobe level in a wide bandwidth range. In addition, by controlling the length of each or at least one slot, a flat gain distribution can be achieved across the entire frequency band.

[0042] According to one embodiment of the present invention, each slot can act as a magnetic current element, together with the two radiating edges of the radiating antenna element 110, to generate a linear magnetic current array with high directivity. In this way, the antenna structure 100 can excite the transverse magnetic field TM4n+1,0 mode and maintain a stable broadside radiation pattern or field shape over the entire operating frequency band.

[0043] Figure 2 FIG. 1 is an XZ plane diagram and an electric field diagram of an antenna structure 100 according to an embodiment of the present invention. Figure 2 In the illustrated embodiment, the radiating antenna element 110 is a patch antenna operating in TM13,0 mode. The antenna structure includes six waveguide-spaced slots (e.g. Figure 1 SL-1 to SL-6 shown in the figure, where the slot positions in TM13,0 mode are as follows Figure 2 As shown, arrows around radiating antenna element 110 represent the electric field generated by antenna structure 100 . Figure 2 The center line indicated in shows the arrangement position of the through hole 33 .

[0044] In the embodiment of the present invention, the electric field on the aperture (or small hole) of the slot SL-1αSL-(2*n) will generate a radiated magnetic current by appropriately selecting the position of the slot SL-1αSL-(2*n), so that SL-1~SL-(2*n) together with the two edges of the radiating antenna element 110 form a (2n+2) element magnetic current array with high directivity. Figure 2 As shown, an 8-element magnetic current array with high directivity is formed, namely slots SL-1αSL-6, plus two edges on the width of the radiating antenna element 110 (the sides of the radiating antenna element 110 extending along the Y axis).

[0045] Figure 3FIG. 4 is a cross-sectional schematic diagram of an antenna structure according to an embodiment of the present invention. Figure 3 An XZ plane view of the antenna structure 100 is also shown. Figure 4 is another schematic cross-sectional view showing an antenna structure according to an embodiment of the present invention. Figure 4 A YZ plane view of the antenna structure 100 is shown.

[0046] According to an embodiment of the present invention, the reference ground plane 120 includes two apertures, each of which is used to accommodate one of the feed terminals (or feed terminals) 35-1 and 35-2. A pair of differential feed terminals (or feed terminals) 35-1 and 35-2 are configured to electrically couple one end of a pair of transmission lines TL-1 and TL-2 to the radiation antenna element 110. A pair of differential feed terminals 35-1 and 35-2 pass through the apertures of the reference ground plane 120 and do not contact the reference ground plane 120. For example, the aperture of the reference ground plane 120 is larger and the diameter of the differential feed terminals 35-1 and 35-2 is smaller, so there is an insulating material (such as a material in a substrate, etc.) between the two, so that there is no electrical connection between the differential feed terminals 35-1 and 35-2 and the reference ground plane 120.

[0047] The upper ends of the feeding terminals 35-1 and 35-2 are electrically coupled to the radiating antenna element 110, and the lower ends of the feeding terminals 35-1 and 35-2 are electrically coupled to one end TL-1 and TL-2 of a pair of transmission lines, and the other ends of the transmission line pair TL-1 and TL-2 can be electrically coupled to a pad of a semiconductor chip (not shown). According to one embodiment of the present invention, the semiconductor chip can be a radio frequency (RF) semiconductor chip, wherein RF signals such as millimeter wave signals to or from the radiating antenna element 110 can be transmitted through a pair of transmission lines TL-1 and TL-2 and a pair of differential feeding terminals 35-1 and 35-2.

[0048] According to one embodiment of the present invention, the distance from any fixed point (e.g., the center point) on the center line of the radiating antenna element 110 to each feeding terminal is equal. That is, in the embodiment of the present invention, the feeding terminals 35-1 and 35-2 are designed to be equidistant from the center line of the radiating antenna element 110. Figure 2 As shown, the electric fields at points equidistant from the center line of the radiating antenna element 110 are directed in opposite directions. Figure 2 The center line in the diagram is the axis of symmetry, and the electric field directions on both sides are 180° opposite, so Figure 2The electric field directions on both sides of the center line are symmetrical about the center line. Therefore, a pair of feeding terminals 35-1 and 35-2 form a differential feeding structure, and there will be a 180-degree phase difference between the signals sent or received by the radiating antenna element 110 through the feeding terminals 35-1 and 35-2. In an embodiment of the present invention, the differential feeding structure is used to excite the TM4n+1,0 mode and maintain a stable broadside radiation pattern over the entire operating frequency band.

[0049] Figure 5 is a schematic top view of an antenna structure proposed according to an embodiment of the present invention, which is a perspective view showing an implementation of a transmission line. Figure 5 In the illustrated embodiment, a pair of differential lines is used as the transmission lines TL-1 and TL-2 in the feeding network to implement a differential feeding structure with feeding terminals 35-1 and 35-2. In addition, two feeding terminals (or feeding vias, which may be metal vias) 35-1 and 35-2 with a phase difference of 180 degrees are placed on both sides of a via (e.g., a short-circuit via) 33 and connected to the radiating antenna element 110 and the transmission lines TL-1 and TL-2.

[0050] Figure 6 is a schematic top view of an antenna structure according to another embodiment of the present invention, which is a perspective view showing another implementation of a transmission line. Figure 6 In the illustrated embodiment, two delay lines are used as a pair of transmission lines in the feeding network to implement a differential feeding structure with feeding terminals 35-1 and 35-2. In addition, two feeding terminals (or feeding vias, which may be metal vias) 35-1 and 35-2 with a phase difference of 180 degrees are placed on both sides of a via (e.g., a short-circuit via) 33 and connected to the radiating antenna element 110 and a pair of transmission lines.

[0051] In addition, the pair of transmission lines may include a first transmission line segment SG-1, a second transmission line segment SG-2, and a third transmission line segment SG-3. One end of the first transmission line segment SG-1 is electrically coupled to the lower end of the feeding terminal 35-1, and one end of the second transmission line segment SG-2 is electrically coupled to the lower end of the feeding terminal 35-2. The other end of the first transmission line segment SG-1 is connected to the third transmission line segment SG-3 to form a delay line as the transmission line TL-1, and the other end of the second transmission line segment SG-2 is connected to the third transmission line segment SG-3 to form another delay line as the transmission line TL-2. The difference between the length l1 of the first transmission line segment SG-1 and the length l2 of the second transmission line segment SG-2 can be designed to be equal to or substantially equal to λg / 2 to have a phase difference of 180 degrees. Therefore, in the present invention, the number and arrangement positions of the plurality of slots are symmetrical about the first line, and the plurality of through holes are arranged along the first line, and differential feeding terminals 35-1 and 35-2 are arranged, and the positions of the differential feeding terminals 35-1 and 35-2 can also be symmetrical about the first line, so that the TM4n+1,0 mode and the electric field with a phase difference of 180° can be realized. In addition, the difference between the length l1 of the first transmission line segment SG-1 and the length l2 of the second transmission line segment SG-2 is equal to λg / 2, so that differential feeding can be realized.

[0052] Figure 7 7 is a schematic cross-sectional view showing an exemplary antenna package (AiP) with a proposed antenna structure according to an embodiment of the present invention. AiP 700 may include one or more antenna structures, such as the antenna structure 100 proposed in the above specification, and a semiconductor chip, such as an RF semiconductor chip 730.

[0053] Two radiating antenna elements 710-1 and 710-2 are included in the antenna structure of AiP 700 and are arranged in the first conductive layer. Figure 7 , schematic side views of radiating antenna elements 710-1 and 710-2 are shown, which are YZ plane views as shown above. In this embodiment, radiating antenna element 710-1 can act as a transmit (TX) antenna and radiating antenna element 710-2 can act as a receive (RX) antenna.

[0054] Both radiating antenna elements 710 - 1 and 710 - 2 may be loaded with multiple slots and may be electrically connected to the reference ground plane GND through multiple vias as shown above.

[0055] One or more reference ground planes GND are included in the antenna structure of AiP 700 and are arranged in at least a second conductive layer below the first conductive layer. The antenna structure of AiP 700 includes two feeding networks. The RF semiconductor chip 730 is electrically coupled to the antenna structure of AiP 700 through the feeding network. Each feeding network may include a pair of transmission lines and a pair of differential feeding terminals arranged in a third conductive layer below the second conductive layer. Figure 7 This is a side view of the feed network, so only one feed terminal and part of a transmission line are shown in each feed network. Figure 7 As shown, feed terminal 35 -TX electrically connects one end of transmission line TL_TX to radiating antenna element 710 - 1 , while feed terminal 35 -RX electrically connects one end of transmission line TL_RX to radiating antenna element 710 - 2 .

[0056] It should be noted that, in addition to the first, second and third conductive layers, one or more other conductive layers may be implemented in the antenna structure of AiP 700 without departing from the scope of the present invention. In addition, AiP 700 may further include a substrate 75, and one or more antenna structures may be disposed in and on the substrate 75. The substrate 75 may be a ceramic substrate, a semiconductor substrate, a dielectric substrate, a glass substrate, but is not limited thereto. According to one embodiment, the substrate 75 may be a package substrate or a printed circuit board (PCB) including, for example, FR4 material or high-performance millimeter wave PCB material, but is not limited thereto. In addition, one or more conductive elements 77, such as solder balls, copper pillars or plug-in terminals, may be provided around the RF semiconductor chip 730.

[0057] Figure 8 is a schematic diagram showing a radiation pattern of an antenna structure proposed in an electric-plane (E-plane) according to an embodiment of the present invention. Fig. 9 is a schematic diagram showing a radiation pattern of an antenna structure proposed in a magnetic-plane (H-plane) according to an embodiment of the present invention. Figure 8 and Fig. 9 A normalized gain plot (or standardized gain plot) is shown, where each radiation pattern is normalized by the maximum gain. Figure 8 and Fig. 9 As shown in the figure, the proposed antenna structure performs well at millimeter wave frequencies (e.g., 77-89 GHz). In addition, a stable broadside radiation pattern can be maintained over the entire operating frequency band. In addition, since the E-plane has a narrow radiation beam width and the H-plane has a wide radiation beam width, the requirements of a fan-beam antenna are met.

[0058] According to an embodiment of the present invention, the shape of the radiating antenna element can also be flexibly designed, and the length and width of each slot can be varied and tuned to obtain a flat gain and a low sidelobe level.

[0059] Fig.10 is a schematic diagram showing different shapes of radiating antenna elements implemented in an antenna structure according to an embodiment of the present invention. Fig.10 In the embodiment, the width w1 of the center of the radiating antenna element 810 and the width w2 of the edge of the radiating antenna element 810 can be different, wherein w1>w2 is designed to form a tapered patch antenna. In addition, the length and width of the etching groove can also be different. For example, in Fig.10 In , the length t1 of the slot closest to the center line is greater than the length t2 of the adjacent slot (sandwich slot), and the length t2 of the sandwich slot is greater than the length t3 of the adjacent slot closest to the edge of the radiating antenna element 810. For another example, in Fig.10 , the width s1 of the slot closest to the center line is greater than the width s2 of the adjacent slot (sandwich slot), and the width s2 of the sandwich slot is greater than the width s3 of the slot closest to the edge of the radiating antenna element 810. By adjusting the length and width of each slot, the energy radiated by each aperture can be adjusted, thereby suppressing the sidelobe level.

[0060] According to another embodiment of the present invention, the proposed antenna structure can also be applied in an array environment, where multiple proposed antenna structures can be arranged adjacent to form an antenna array. For example, in one embodiment of the present invention, two (or more) proposed antenna structures can be placed half a wavelength apart while still maintaining good isolation across the entire frequency band.

[0061] In summary, the proposed antenna structure is a compact, low-profile design for high gain, low sidelobe, and fan-shaped beam patterns. A row of shorting vias placed along the center of the radiating antenna element can be used to suppress any even-order TM modes excited throughout the structure and isolate the two feed terminals. In addition, the proposed antenna structure is differentially fed, and the differential feed structure is used to excite the TM 4n+1,0 mode and maintain a stable broadside radiation pattern over the entire operating frequency band. In addition, by controlling the shape of the radiating antenna elements and the slots, a gradual taper of the amplitude in the radiation pattern can be obtained, thereby providing low sidelobe levels over a wide bandwidth range. The shape of the radiating antenna elements can also be modified from rectangular to trapezoidal, which can reduce the sidelobe level. In addition, by controlling the length of each or at least one time slot, a flat gain distribution can be achieved over the entire frequency band. The present invention realizes the desired antenna pattern, such as Figure 2 As shown, the differential feeding structure in the present invention stimulates TM 4n+1,0mode, specifically, a field pattern distribution of 13 (4*3+1) half wavelengths is realized. Of course, different numbers of slots can be set as needed (changing the number of n) to realize field pattern distributions of other numbers of half wavelengths.

[0062] Those skilled in the art will readily observe that many modifications and variations of the apparatus and method can be made while maintaining the teachings of the present invention.Accordingly, the above disclosure should be interpreted as being limited only by the metes and bounds of the appended claims.

Claims

1. An antenna structure, characterized in that: include: a radiating antenna element disposed in the first conductive layer; as well as A reference ground plane is disposed in a second conductive layer below the first conductive layer, wherein the radiating antenna element is loaded with a plurality of slots, the radiating antenna element is electrically connected to a reference ground plane through a plurality of through holes, and The plurality of through holes are placed along a first line of the radiating antenna element, the plurality of slots are placed along a second line perpendicular to the first line, the first line is a center line of the radiating antenna element, and the slots are evenly distributed on both sides of the through hole; The antenna structure also includes: a feeding network, including: a pair of transmission lines, the pair of transmission lines being arranged in a third conductive layer below the second conductive layer, the pair of transmission lines being a pair of differential lines, and a pair of differential feeding terminals being distributed on both sides of the through hole, and A pair of differential feed terminals, wherein the pair of differential feed terminals are configured to electrically couple one end of the pair of transmission lines to the radiating antenna element, the radiating antenna element being a patch antenna.

2. The antenna structure according to claim 1, characterized in that: The antenna structure is configured to operate with a predetermined radio frequency signal having a radio frequency frequency and a corresponding wavelength λg, and wherein a distance between adjacent slots is equal to λg.

3. The antenna structure according to claim 2, characterized in that: The length of at least one of the grooves is equal to λg / 2.

4. The antenna structure according to claim 1, characterized in that: The antenna structure is configured to operate with a predetermined radio frequency signal having a radio frequency and a corresponding wavelength λg, and the pair of transmission lines includes a first transmission line segment and a second transmission line segment, wherein the difference between the length of the first transmission line segment and the length of the second transmission line segment is equal to λg / 2.

5. An antenna package, characterized in that: include: An antenna structure, comprising: a radiating antenna element, arranged in a first conductive layer; a reference ground plane, arranged in a second conductive layer below the first conductive layer, wherein the radiating antenna element is loaded with a plurality of slots, and the radiating antenna element is electrically connected to the reference ground plane through a plurality of through holes; and a feeding network, comprising a pair of transmission lines, arranged in a third conductive layer below the second conductive layer, the pair of transmission lines being a pair of differential lines, a pair of differential feeding terminals being distributed on both sides of the through holes, and a pair of differential feeding ends, wherein the pair of differential feeding ends are used to electrically couple one end of the pair of transmission lines to the radiating antenna element, the radiating antenna element being a patch antenna, the plurality of through holes being placed along a first line of the radiating antenna element, the plurality of slots being placed along a second line perpendicular to the first line, the first line being a center line of the radiating antenna element, and the slots being evenly distributed on both sides of the through holes; and The semiconductor chip is electrically coupled to the antenna structure through the feeding network.

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