An antenna array includes one or more antenna tiles which are arranged on an antenna plane. Each of the one or more antenna tiles includes one or more antenna units that are arranged together to form the respective antenna tile having a hexagonal shape and each antenna unit comprises an antenna circuit chip. In some embodiments, each antenna unit has a pentagonal shape and the antenna tile has a hexagonal shape formed by tessellating the one or more antenna units with one another.

TECHNICAL FIELD

The disclosed embodiments relate generally to antenna technology, including but not limited to methods and systems associated with a directional antenna array with monohedral tiling of antenna units, where each unit accommodates additional functional components (e.g., interconnects, connectors, active and passive electronic devices, and heat sinks).

BACKGROUND

Multiple antenna units are often connected to work as a single antenna or an antenna array for receiving or transmitting radio waves. In such an antenna or antenna array, individual antenna units are controlled with correlated phases to create a steerable beam of radio waves pointing in different directions without moving the antenna array. Each antenna unit has a dimension consistent with a frequency of the associated radio waves. However, it has been a challenge to integrate multiple mechanical, electrical, and thermal functional components within a limited space of each antenna unit. Some of the functional components of each antenna unit have to be moved out of the antenna unit and disposed remotely on an antenna level, which introduces undesirable electrical parasitics and assembly complexity to the antenna. It would be beneficial to develop cost-effective antenna arrays that have sufficient local space in each antenna unit for accommodating additional functional components (e.g., interconnects, connectors, active and passive electronic devices, and heat sinks) while preserving or enhancing a high gain and low sidelobes of the antenna array.

BRIEF SUMMARY

Various implementations of systems, methods and devices within the scope of the appended claims provide a customizable, scalable, and cost effective antenna, e.g., an antenna including one or more antenna tiles formed by one or more antenna units having a pentagon. In particular, the antenna is configured to scale infinitely in in-plane directions of the antenna as one tile geometry is tessellated along the in-plane directions. In some embodiments, the antenna array is configured to operate in any of the X-Band (8-12 GHz), the Ku-Band (12-18 GHz), the K-Band (18-27 GHz), the Ka-Band (27-40 GHz), the V-Band (40-75 GHz) and the W-Band (75-110 GHz) frequency ranges. The antenna array allows for frequency increases from the X-Band, to the Ku-Band, K-Band, Ka-Band, to the V-Band, and then to the W-Band. Further, the antenna is configured to meet antenna design goals and allows for testing and calibration at the tile level prior to antenna integration, which can drastically reduce calibration and rework costs.

In example embodiments, an antenna tile is disclosed, wherein the antenna array includes one or more antenna units, wherein each antenna unit has a pentagonal shape, and the antenna tile has a hexagonal shape formed by tessellating the one or more antenna units with one another.

In some embodiments, the one or more antenna units include a first antenna unit, a second antenna unit, and a third antenna unit. In some embodiments, the second antenna unit is substantially identical to the first antenna unit and the third antenna unit is substantially identical to the first antenna unit and second antenna units.

In some embodiments, each antenna unit has at least one of a pentagonal shape, a rhombus shape, a kite shape, or a trapezoidal shape.

In some embodiments, each antenna unit has a convex pentagonal shape and the antenna tile has a convex hexagonal shape.

In some embodiments, the pentagon shape of an antenna unit has a surface area that comprises one third of the hexagonal shape of the antenna tile.

In some embodiments, each antenna unit comprises one or more antenna circuit chips and each antenna circuit chip comprises one or more antenna elements. In some embodiments, each antenna circuit chip comprises at least four antenna elements. In some embodiments, the antenna circuit chip is disposed at a center of the respective antenna unit. In some embodiments, the antenna circuit chip is disposed such that a first corner is disposed adjacent to a corner of the antenna unit and the corner of the antenna unit corresponds to a corner at the center of the antenna tile, and a second corner is disposed adjacent to a middle point of a side of the antenna unit corresponding to the side opposite the center of the antenna tile. In some embodiments, the antenna circuit chip is disposed such that a first side is disposed adjacent to a corner of the antenna unit and the corner of the antenna unit corresponds to a corner at the center of the antenna tile, and a second side is disposed adjacent to and substantially parallel to a middle point of a side of the antenna unit corresponding to the side opposite the center of the antenna tile.

In some embodiments, each antenna unit comprises one or more ports and each of the one or more ports are disposed at an open area external to an antenna circuit chip. In some embodiments, the one or more ports include at least one or a power and control port or a radio frequency port.

In some embodiments, each antenna unit is configured with a heat sink, and the heat sink comprises one or more fluid cooling inlets, one or more fluid cooling outlets, a fluid cooling chamber and one or more fluid channels fluidically coupled to the one or more fluid cooling inlets, the fluid cooling outlet, and the fluid cooling chamber. In some embodiments, at least one of the one or more fluid cooling inlets or one or more fluid cooling outlets are coupled to one or more pumps configured to promote the flow of cooling fluid throughout the heat sink.

In example embodiments, an antenna array is disclosed, wherein the antenna array includes one or more antenna tiles and the one or more antenna tiles are arranged on an antenna plane, each antenna tile comprises one or more antenna units that are arranged together to form the respective antenna tile having a hexagonal shape, and each antenna unit comprises an antenna circuit chip.

In some embodiments, each antenna tile comprises three separate and distinct antenna units tessellated together.

In some embodiments, each antenna tile has a convex hexagonal shape, and each antenna unit comprising the antenna tile has a pentagonal shape.

In some embodiments, one or more sides of the antenna array have a length consistent with a characteristic frequency of the antenna array. In some embodiments, the characteristic frequency is based at least in part on a desired wavelength of radio frequency signals to be received or transmitted by antenna array elements of the antenna array.

In some embodiments, each antenna tile has a concave hexagonal shape.

In some embodiments, the antenna plane is flat.

In some embodiments, the antenna plane is curved in one or more dimensions.

In some embodiments, an antenna board configured to provide the antenna plane, wherein the one or more antenna tiles are assembled on the antenna board.

In some embodiments, each antenna tile is electrically coupled to at least one of the antenna board or one or more other antenna tiles.

In some embodiments, each antenna unit of an antenna tile is electrically coupled to at least one of the antenna board, the one or more other antenna units of the antenna tile, or one or more other antenna units of an adjacent antenna tile.

In some embodiments, the antenna array operates within an X-Band, a Ku-Band, a K-Band, a Ka-Band, a V-Band, or a W-Band frequency range.

In some embodiments, the antenna array has a scan angle up to positive 60 degrees or negative 60 degrees off an associated boresight.

In some embodiments, the antenna array has a half-power beam width (HPBW) less than 6 degrees.

In some embodiments, the antenna array includes at least a first antenna tile and a second antenna tile, and the first antenna tile and second antenna tile have substantially the same dimensions.

In some embodiments, the antenna array includes at least a first antenna tile and a second antenna tile, and the first antenna tile and second antenna tile have different dimensions.

In example embodiments, an antenna is disclosed, wherein the antenna an antenna unit having a polygon shape that is configured to form the basis of a monohedral tiling arrangement of identical antenna units.

In some embodiments, the antenna unit has a convex polygon shape.

In some embodiments, the antenna unit has a concave polygon shape.

In some embodiments, the antenna unit a single antenna unit.

In some embodiments, the antenna unit is a first antenna unit and the antenna further includes one or more additional antenna units substantially identical to the first antenna unit.

In some embodiments, the first antenna unit and the one or more additional antenna units are tessellated with one another so as to form discrete antenna tiles.

In some embodiments, each discrete antenna tile is tessellated with one or more other antenna tiles so as to form a discrete antenna array.

DETAILED DESCRIPTION

Numerous details are described herein in order to provide a thorough understanding of the example embodiments illustrated in the accompanying drawings. However, some embodiments may be practiced without many of the specific details, and the scope of the claims is only limited by those features and aspects specifically recited in the claims. Furthermore, well-known processes, components, and materials have not been described in exhaustive detail so as to avoid obscuring pertinent aspects of the embodiments described herein.

In some implementations of this application, an antenna (also called antenna array when it includes more than one antenna unit) includes an antenna unit having a pentagonal shape and configured to be arranged with one or more additional antenna units to form an antenna tile having a hexagonal shape. In some embodiments, the antenna further includes at least one additional antenna tile that is substantially identical to the antenna tile, i.e., monohedral tiling of the antenna tiles of the hexagonal shape is applied to form the antenna. Alternatively, in some embodiments, the antenna further includes at least one additional antenna tile that is different from the antenna tile is applied to form the antenna such that the antenna may perform multi-frequency band operations. Further, in some embodiments, the antenna tiles of the same orientation fit to one another to form the antenna. In each antenna tile, the antenna units are identical, and however, arranged according to different orientations to form the respective antenna tile. The shape of each antenna unit is configured to accommodate both an antenna circuit chip and additional functional components, e.g., power and data interconnects, power and data connectors, cooling channels and connectors, and heat sinks.

In some situations, monohedral equilateral triangle and square tiles are used to create planar Active Electronically Scanned Arrays (AESAs), as these polygons can be naturally tesselate with each other, and can be used to expand the AESAs infinitely in their in-plane directions. In an example, individual antenna elements configured to receive and transmit radio waves are optionally disposed at centers of these monohedral equilateral tiles. Adjacent centers of the equilateral triangle tiles can be connected to form equilateral triangles, and adjacent centers of the square tiles can be connected to form squares. In such monohedral tiling, each antenna element is connected to one or more electronic devices (e.g., formed in Integrated Circuit (IC)) for phase shifting, time delay, and/or amplification. Such equilateral triangle and square tiles need to provide a tile space to support additional functional components.

FIG.1is a top view of an antenna array100, in accordance with some embodiments. The antenna array100includes one or more antenna tiles110that are arranged on an antenna plane105. The antenna plane105can be provided by an antenna board (e.g., a Printed Circuit Board (PCB) board (not shown) behind the antenna plane). Each antenna tile includes one or more separate and distinct antenna units120that, when are arranged together, form the respective antenna tile110. Further, each antenna unit120includes an antenna circuit chip130and one or more ports (shown and discussed below inFIGS.2A-2C). In some embodiments, the antenna plane105is flat. Conversely, in some embodiments, the antenna plane105is curved in one or more dimensions. In some embodiments, the antenna array100operates within one or more of a X-Band, Ku-Band, K-Band, Ka-Band, V-Band, and/or W-Band frequency range. In some embodiments, the antenna array100has a scan angle up to +/−60° and a HPBW less than 6° (theta) 0=0° when operating at the X-Band frequency. In some situations, the HPBW is less than 4° (theta) 0=0° when operating at the Ku-Band. In some situations, the HPBW is less than 3° (theta)0=0° when operating at the K-Band frequency range. In some situations, the HPBW is less than 2° (theta) 0=0° when operating at the Ka-Band. In some situations, the HPBW is less than 1° (theta)0=0° when operating at the W-Band. In some embodiments, when the antenna array100operates at a given frequency, the antenna array100may select one or more of the antenna tiles and/corresponding antenna units to perform the desired operations (e.g., transmit radio waves and/or receive radio waves). The one or more antenna tiles and/or antenna units may be specifically configured to operate at a particular radio wave frequency and/or wavelength.

In some embodiments, the antenna array100is formed from tessellating one or more antenna tiles110with one another. The one or more antenna tiles110are substantially identical. In some embodiments, the one or more antenna tiles110are identical. Each antenna tile110has a convex hexagonal shape or a concave hexagonal shape. Each antenna tile110includes one or more separate and distinct antenna units120that, when arranged together, form the respective antenna tile110. In some embodiments, each antenna tile110includes at least three separate and distinct antenna units120that are arranged together to form the respective antenna tile110. For example, as shown inFIG.2C, an antenna tile110can include a first, second, and third antenna unit120a-120c,that are substantially identical with one another. A plurality of antenna tiles110are tessellated with one another so as to form the antenna tile110.

In some embodiments, a plurality of antenna units120, when tessellated with one another, form a discrete antenna tile110. The plurality of antenna units120are configured to closely fit together to form the antenna tile110. Each antenna unit120may be substantially identical to other antenna units120. In an example, the antenna units120includes three identical rhombuses that closely fit into and fill an antenna tile110(e.g., tiles1302and1306inFIG.13). In another example, the antenna units120includes three identical pentagons that closely fit into and fill an antenna tile110(e.g., tile1304inFIG.13). Alternatively, in some embodiments, the antenna units120in the same tile110can be different. For instance, a first antenna unit120has a kite shape and two other antenna units are trapezoids that closely fit into and fill an antenna tile110(e.g., tile1310inFIG.13) with the kite shape. The kite shaped antenna unit120and the two trapezoid shaped antenna units120optionally have equal areas. In another example, the antenna units120includes three pentagons that closely fit into and fill an antenna tile110(e.g., tile1308inFIG.13) and however have at least two different pentagonal shapes. As such, each antenna unit120optionally has a pentagon shape, a rhombus shape, a kite shape, and/or a trapezoid shape. The antenna unit120can have different monohedral shapes (e.g., a shape from the set of monohedral pentagons). Additionally, each antenna unit120optionally has a convex or concave shape, so does each antenna tile110. Different tessellated configurations of an antenna tile110are provided below with reference toFIG.13.

In some embodiments, each antenna unit120includes an antenna circuit chip130, which includes one or more antenna elements. In some embodiments, each antenna unit120includes four antenna elements140disposed at four corners of the antenna circuit chip130. In some embodiments, each antenna circuit chip130is disposed at a center of the respective antenna unit120. Additionally or alternatively, in some embodiments, each antenna circuit chip130is aligned with a corner or a side of the antenna unit120. For example, the antenna unit120has a pentagon shape, and the antenna circuit chip130has a first corner and a second corner opposing each other. The antenna circuit chip130is oriented, such that the first corner is disposed adjacent to a corner of the antenna unit120(i.e., a center of the antenna tile110), and the second corner is disposed adjacent to a middle point of a side of the antenna unit120facing the corner of the antenna unit120. Alternatively, in some embodiments not shown inFIG.1, a first side of each antenna circuit chip130is adjacent to the center of the antenna tile110, and a second side opposing the first side is adjacent to and substantially parallel to a side of the corresponding antenna unit120facing the center of the antenna tile110. As such, the center of antenna tile110is optionally disposed adjacent to a corner or a side of the antenna circuit chip130.

In some embodiments now shown inFIG.1, each antenna unit120includes one or more ports. For example, the one or more ports can include a power and control port (e.g., SAMTEC stacker230inFIG.2B) or a radio frequency (RF) port (e.g. MMSP (Micro-Mode) connector240inFIG.2B, Corning G4PO connectors). Examples of the MMSP connector224include, but are not limited to, MMSP-3526, MMSP-3268 and MMSP-3514. In some embodiments, the one or more ports are disposed at an open area external to a footprint of the antenna circuit chip130.

As described above, the antenna array100is arranged on an antenna plane105that is optionally provided by the antenna board, and one or more identical or substantially identical antenna tiles110are closely assembled on the antenna board. In some embodiments, each antenna tile110is electrically coupled to at least one of the antenna board and/or a subset of antenna tiles110to which the antenna tile110is immediately adjacent. In some embodiments, each antenna unit120of each antenna tile110is electrically coupled to at least one of the antenna board, two other antenna units120within the same antenna tile110, and/or a subset of antenna tiles110to which the antenna tile110is immediately adjacent. In some embodiments, the antenna board includes connectors configured to electrically couple to the one or more ports of an antenna unit120. The antenna board may comprise various components to facilitate the hosting of signal routing, including but not limited to direct current (DC) power distribution, control signaling, clock distribution, charge storage, bypassing, connector interfaces, and/or the like. The antenna board may be comprised of any suitable material capable of hosting signal routing. For example, the board may be comprised of high frequency optimized FR4 variant thermoset plastic. Radio frequency (RF) signals may be routed on and/or through the antenna board using impedance controlled trace geometries. For example, control signals and clocks may be distributed using phase matched, impedance controlled, differential trace geometries. Examples of the tessellated antenna tiles110is provided below with reference toFIGS.3A and3B.

In some embodiments, each antenna unit120further includes a coolant port, and the coolant port is disposed at an open area of the antenna unit120and configured to let a coolant (e.g., air, water) enter and exit the antenna unit120to cool the antenna unit120. Examples of the coolant port are provided below with reference toFIGS.8-12B.

FIGS.2A and2Bare a front side perspective view and a bottom perspective view of an antenna unit120, in accordance with some embodiments, respectively.FIG.2Cillustrates an antenna tile110including a plurality of antenna units120, in accordance with some embodiments.FIG.2Ashows an aperture side210of the antenna unit120from which radio waves are transmitted or received by one or more antenna elements. In the antenna unit120, the one or more antenna elements of the antenna unit120are coupled to an antenna circuit chip130that includes a subset or all of an radio frequency (RF) front end (i.e., a transmitter/receiver chip). The RF front end includes a RF transmitter front end and an RF receiver front end. In some situations, the RF front end of the antenna circuit chip130generates one or more electrical signals and drives the antenna elements of the antenna unit120to emit electromagnetic waves in space, e.g., when a cellular phone transmits a signal toward a satellite in order to place a call or determine a location of the cellular phone via a global positioning system. Conversely, in some embodiments, the antenna elements of the antenna unit120receive one or more electromagnetic waves from free space and converts the electromagnetic waves to an RF electrical signal that can be processed by the RF Frontend on the antenna circuit chip130, e.g., when a radio device receives radio waves and converts the radio waves into an electrical signal that is translated to music outputted from a radio device.

In some embodiments, the subset of the RF front end of the antenna circuit chip130are configured for adjusting phase, time delay, and/or relative magnitudes of different signals. Specifically, the antenna circuit chip130including the RF front end has one or more of: low pass filters (LPF), intermediate frequency (IF) filters, power amplifiers, oscillators, mixers, digital-to-analog converters (DAC), and analog-to-digital converters (ADC). Additionally, in some embodiments, the antenna circuit chip130further includes a power management integrated circuit (PMIC) and/or a baseband circuit in addition to the RF front end. The PMIC is configured to manage power for the antenna unit120, and the baseband circuit is configured to provide low frequency signals that carry information to be transmitted by the antenna element(s) of the antenna unit120and process low frequency signals converted from RF signals received by the antenna element(s). Conversely, in some embodiments, the PMIC, the baseband circuit, and a subset of the RF front end are not integrated on the antenna circuit chip130, and however, are optionally contained in an additional space of the antenna unit120that does not overlap a footprint of the antenna circuit chip130. More details on electronic components of the antenna unit120are discussed below with reference toFIG.8.

In an example, the antenna circuit chip130includes an amplifier chip, e.g., a power amplifier, a low noise amplifier. In some embodiments, each antenna circuit chip130includes one or more antenna elements140. For example, as shown inFIG.2A, the antenna circuit chip130includes four antenna elements140at each corner of the antenna circuit chip130. The antenna circuit chip130shown inFIG.2Ais a non-limiting example.

In some embodiments, one or more sides215of an antenna unit120have a length consistent with a characteristic frequency of the antenna array100. In some embodiments, the length of the one or more sides215of the antenna unit120is 3 cm. In some embodiments, the length of the one or more sides215of the antenna unit120is equal to the wavelength (k). In other embodiments, the length of the one or more sides215of the antenna unit120is equal to the wavelength (k) multiplied by a scaling factor. More details on the length of the one or more sides215of the antenna unit120is discussed below with reference toFIG.4.

FIG.2Bshows a connector side220of the antenna unit120that is opposite the aperture side210. In some embodiments, the connector side220of the antenna unit120includes one or more ports and a heat sink250. The one or more ports include a power and control port (e.g., SAMTEC stacker230) or an RF port (e.g. MMSP240). In some embodiments, the power and control port and the RF port can be a single port (which requires signal isolation among different types of signals, e.g., between RF signals and digital control signals). The one or more ports shown inFIG.2Bare non-limiting examples. Any different number of ports can be used depending on the use case.

The heat sink250is configured to absorb and dissipate heat generated by the internal components of the antenna unit120(e.g., heat generated by the RF front end). In some embodiments, the heat sink250is air cooled when the air is circulated over the connector side220of the antenna unit120. Alternatively, in some embodiments, the antenna unit120includes one or more cooling ports (e.g., an inlet and an outlet) configured to cool the antenna unit120in a controlled manner using a coolant. More details on the one or more cooling ports are discussed below with reference toFIGS.8-12B.

FIG.2Cshows an antenna tile110formed by at least three separate and distinct antenna units120. For example, the antenna tile110is formed by a first antenna unit120a,a second antenna unit120b,and a third antenna unit120ctessellated with one another. The first, second, and third antenna units120a-120cfit into and fill the antenna tile110, i.e., without leaving an unfilled open area (e.g., greater than a threshold size) on the antenna tile110. In this example, the first and second antenna units120aand120bare substantially identical to one another, and the third antenna unit120cis substantially identical to the first and second antenna units120aand120b.In some embodiments, for each antenna tile110, two sides (e.g.,215aand215b) of each antenna unit120connect a center of the antenna tile110to sides of the antenna tile110. The two sides215aand215bare substantially equal and have a length consistent with a characteristic frequency of the antenna array100. The length of the two sides215aand215bare selected to allow the at least three separate and distinct antenna units120of the antenna tile110to form a hexagon antenna tile110when the antenna units120are tessellated with one another.

FIGS.3A and3Bare front side and back side perspective views of an antenna array300having tessellated antenna tiles110, in accordance with some embodiments, respectively. The front side of the antenna array300corresponds to the aperture side210of the antenna unit120where electromagnetic waves are received and transmitted. At least three antenna tiles110a-110care tessellated together to form the antenna array300, and the antenna array300is scalable with a variation of a number of antenna tiles110being tessellated in the antenna array300. In some embodiments, each antenna tile110a-110cis electrically coupled to at least one of an antenna board (no shown) and/or a subset of antenna tile110to which the antenna tile110is immediately adjacent. For example, a first antenna tile110ais electrically coupled to the antenna board or at least the second or third antenna tile110bor110c(which is adjacent to the first antenna tile110a). In some embodiments, for each antenna tile110a-110c,each of the three antenna units120for each antenna tile110is electrically coupled to at least one of the antenna board, two other antenna units120within the antenna tile110, and/or a subset of antenna tiles110to which the respective antenna tile110is immediately adjacent. For example, the first antenna unit120aof the first antenna tile110ais electrically coupled to the antenna board, the second or third antenna unit120bor120C, or at least one of the second, third, or any other antenna tiles110that are adjacent to the first antenna tile110a.

Referring toFIG.3B, one or more ports of each antenna unit120are exposed and left unobstructed on the back side of the antenna array300. Each antenna unit120is configured to be electrically coupled to at least one of the antenna board and adjacent antenna units120(e.g., via the one or one or more ports). In some embodiments, each antenna unit120is individually controlled via the one or more ports. In some embodiments, the one or more antenna units120of an antenna tile110are configured to operate jointly with one another, thereby producing a desired result at the antenna tile110as a whole. In some embodiments, each antenna tile110is individually controlled via its respective one or more antenna units120. In some embodiments, the one or more antenna tiles110are configured to operate jointly with one another, thereby producing a desired result for the antenna array100as a whole. Each antenna unit120and/or antenna tile110can be individually tested. Each antenna unit120can be removed or replaced with another antenna unit120, e.g., in case of malfunctioning or damaged antenna units120.

It is noted that the antenna array300includes three antenna tiles110, and one skilled in the art would understand that any different number of antenna tiles110can be tessellated together to from an antenna array of a desired size and having desirable electrical and RF performance.

FIG.4A and4Bare geometric diagrams400and450applied to determine one or more geometric parameters of the antenna unit102and the antenna circuit chip130, in accordance with some embodiments. The one or more geometric parameters include, but are not limited to, a length of the sides215aand215bof the antenna unit102and a length or width of the antenna circuit chip130. In some embodiments, the antenna unit120is configured to operate in one of the X-Band, Ku-Band, K-Band, Ka-Band, and W-Band frequency ranges, and the one or more geometric parameters are determined accordingly. In an example, the antenna unit120has a pentagonal shape including two right angles (i.e., 90 degrees) and three blunt angles of 120 degrees.

The geometric parameters of the antenna unit120are determined based on a characteristic frequency of the antenna array100. For example, the length of sides a and b (instances of side215FIGS.2A-2C) is based on a wavelength (λ) of RF signals to be received and transmitted by the antenna elements of the antenna unit120, and the wavelength of the RF signals is equal to the speed of light (cl) divided by the characteristic frequency, a the wavelength is multiplied by a scaling factor (cλ). The length of sides c and e are equal to the absolute value of the length of side a (or b) times the tangent of (π/6). Further, the length of side d is equal to a sum of the lengths c and e. As such, the antenna unit120having the above geometric parameters provides a footprint that can accommodate both the antenna circuit chip130and additional functional components (e.g., interconnects, connectors, and heat sinks).

In some embodiments, the antenna circuit chip130is a square chip. In some embodiments, each corner of the antenna circuit chip130includes an antenna element140. The antenna circuit chip130is disposed in the antenna unit120, such that a planar surface of the antenna circuit chip130is parallel with the front and back sides of the antenna unit120. A center of the antenna tile110, a first corner of the circuit chip130, a second corner of the circuit chip130opposing the first angle of the circuit chip130, and a center of a side d of the antenna unit120opposing the center of the antenna tile110are aligned. Each antenna elements140located at a respective corner of the circuit chip130is spaced a distance as close to the wavelength divided by 2 (i.e., λ/2) as possible. In other words, in some embodiments, the length of each side of the antenna circuit chip130is equal to the wavelength divided by 2. Such a separation distance substantially equal to (λ/2) suppresses and can minimize grating lobes. Additionally, in some embodiments, the center (centroid) of the RF chip130is positioned coincident with the center of a point defined by the intersection of a line segment from a corner to the midpoint of the opposite side and translated about the line segment by an offset distance. For example, the centroid of the RF chip130may be defined as the position coincident with the center of point A to the midpoint of side d. The offset distance may be defined as the wavelength divided by 10 (i.e., λ/10).

An additional usage area that can accommodate additional functional components (e.g., interconnects, connectors, and heat sinks) besides the antenna circuit chip130may be determined based at least in part on a total area of the antenna unit120(in this case, having a pentagon shape) minus an area of the antenna circuit chip130. As depicted inFIG.4C, conventional prior art solutions utilize square antenna units460such that the prior art usage area may be determined based at least in part on the area of the square antenna unit460minus the area of the antenna circuit chip130. As shown inFIG.4D, given the same antenna circuit chip130and the same separation distance of two antenna elements, the additional usage area430of the antenna unit120is greater than the prior art usage area450approximately by 20%. As such, the antenna unit120of a pentagonal shape fitting into a hexagon antenna tile110provides a larger footprint to accommodate additional functional components.

FIG.5is a graph500illustrating array factor and half-power bean width (HPBW) performance of an antenna array100at different steering angles, in accordance with some embodiments. The graph500shows performance of the antenna array100at a first position (e.g., theta (θ)=0°) represented by a solid line502, and performance of the antenna array100at a second position (e.g., theta (θ)=60°) represented by a broken line504. The antenna array100has a smaller HPWB and includes lower sidelobe value, e.g., than prior art square antenna unit460. In some embodiments, the HPWB at boresight is less than 6°. In some embodiments, the HPWB at boresight is 5.8°. Further, as shown by the solid line502, output signals of the antenna array100have a maximum value at θ=0°, and each measured value at a position other than θ=0° is less than the maximum value. Main lobe of the antenna array100is centered at θ=0°.

The antenna array100further provides grating lobes that are more directional than prior art antenna arrays (e.g., an antenna array made of the prior art square antenna unit460). For example, the solid line inFIG.5is compared with the solid line inFIG.6(which, as discussed below, represents a prior art antenna array at the first position (e.g., theta (θ)=0°)). Total 8 grating lobes (e.g., lobes other than the center or maximum value lobe) are observed to be greater than −35 dB and located between θ=−40° and θ=40°, while total 10 grating lobes are observed to be greater than −35 dB and spread everywhere, i.e., between θ=−90° and θ=90°. As such the grating lobes are more directional in the antenna array100than the prior art antenna array.

Further, the antenna array100useable at greater scan angles than prior art antenna arrays. In particular, in some embodiments, the antenna array100useable up to an angle of +/−60° off an associated boresight. For example, the broken line inFIG.5is compared with the broken line inFIG.6(which, as discussed below, represents a prior art antenna array at the second position (e.g., theta(θ)=60°)). The main lobe for the antenna array100has a clear maximum value (e.g., at theta)(θ)=60°) better than the prior art antenna array (which has a maximum value at theta (θ)=60° that slowly decays rather than a clearly defined maximum value).

FIG.6is a graph600illustrating array factor and HPBW performance of a prior art antenna array at different beam steering angles. The graph600is provided for comparative purposes and shows performance of a prior art antenna array (e.g., a 324-element square array) at the first position (e.g., theta)(θ)=0°) represented by a solid line602, and performance of the prior art antenna array at the second position (e.g., theta)(θ)=60°) represented by a broken line604. As shown in relation toFIG.5, the prior art antenna array has a larger HPWB and includes sidelobe values that remain consistently high. For example, as shown by the solid line, the prior art antenna array has a maximum value at the theta (θ)=0° (its first position) and each measured value at a position other than theta (θ)=0° is less than the maximum value but remains substantially the same (i.e., the sidelobe values do not decrease as shown inFIG.5). Further, the prior art antenna array has grating lobes that are not as directional as the antenna array100(e.g., compare the different number of grating lobes between the solid lines inFIGS.5and6) and is only usable up to a scan angle of up to +/⊕50° (e.g., at the second position the performance of the prior art antenna array is inconsistent or unusable due to the main lobe decaying over scan angle off associated boresight and/or time instead of being clearly defined).

FIG.7is a graph comparing the HPBW performance of the antenna array100and the prior art antenna array, in accordance with some embodiments. The graph700shows the HPBW performance of the antenna array100(represented by the solid line702) and the HPBW performance of a prior art antenna array (represented by the broken line704) at beam steering angles theta (θ) from 0° to 60°. As shown in graph700, the antenna array100has an HPBW value less than 6° at θ=0°, the HPBW value increasing as the angle increases up to an HPBW value less than 12° at θ=60°. Alternatively, the prior art antenna array has an HPBW value over 5° at θ=0°, the HPBW value increasing as the angle increases up to an HPBW value of approximately 8° at θ=50° (the HPBW value of the prior art antenna array was not measurable at 60°).

FIG.19depicts an example configuration of an antenna array1900in accordance with some example embodiments. The particular antenna array1900includes seven antenna tiles1901. Each antenna tile1901includes three antenna units1902, which are tessellated with one another to form the hexagonal shape of the antenna tile1901. In the antenna array1900, each antenna unit1902is identical to the other antenna units and each antenna unit has a pentagonal shape. Furthermore, each antenna unit1902includes an antenna circuit chip1903, which includes four antenna elements1904.

FIGS.20A and20Bdepict a three-dimensional radiation (or beam) pattern of an antenna array, such as the antenna array1900depicted inFIG.19.FIG.20Adepicts a side view of the three-dimensional radiation pattern2000when one or more antenna units of antenna array are operating at a frequency of 37 GHz (i.e., the Ka-Band). A main lobe2001can be seen extending perpendicularly from the top face of the antenna array1900with one or more side lobes2002extending at an angle from the top face of the antenna array1900. A back lobe2003and one or more side lobes2002may also be seen extending from the bottom face of the antenna array1900.

FIG.20Bdepicts an angled view of the three-dimensional radiation pattern 2000′ when operating at a frequency of 37 GHz (i.e., the Ka-Band). The main lobe2001can again be seen extending perpendicularly from the top face of the antenna array1900with one or more side lobes2002extending at an angle from the top face of the antenna array1900. Additionally, the main lobe and one or more side lobes can be seen as centralized at the center of the innermost antenna tile. The main lobe2001of antenna array1900is capable of achieving a directive gain of approximately 24 decibels relative to isotropic (dBi).

FIG.21depicts a two-dimensional radiation pattern for an antenna array, such as antenna array1900as depicted inFIG.19. As shown inFIG.21, a main lobe2101corresponding to a directive gain of approximately 24 dBi can be seen at 0°. The main lobe2101can also be seen to span approximately 7° in width. Additionally, one or more side lobes2102and back lobe2103are shown in the radiation pattern. In particular, one or more sidelobes2102occur at approximately 45°, 135°, −45°, and −135°. Additional sidelobes may be interspersed between the aforementioned angles and/or the main lobe2101and back lobe2103. Furthermore, the one or more side lobes2102correspond to a side lobe level of approximately −11 decibels relative to isotropic (dBi).

FIG.8is a bottom side exploded perspective view of an antenna unit800, in accordance with some embodiments. The antenna unit800includes one or more of: an antenna board810, an ADC and a DAC820, a down converter and up converter830, an antenna circuit chip130, phase shifter and/or time delay chip including digital beamformers840, one or more ports (e.g., SAMTEC stacker230and MMSP240), a heat sink250, one or more fluid cooling inlets850and outlet860, a circuit board870, an embedded processor880, and an anti-aliasing filter890. The antenna unit800can be an instance of the antenna unit120described above. For example, the antenna unit800can be tessellated with one or more other antenna units800to form an antenna tile110and an antenna array100.

In some embodiments, the antenna board810includes a wide angle impedance matcher and/or one or more antenna elements. The antenna board810operates as an outer surface in which the circuit board870is housed (the heat sink250being the bottom portion of the housing). The circuit board870electrically couples one or more components of the antenna unit800, such as the ADC/DACs820, the down converter/up converter830, the antenna circuit chip130, the phase shifter and/or time delay chip including digital beamformers840, the embedded processor880, and the anti-aliasing filter890.

The ADC and DACs820, the down converter/up converter830, and the antialiasing filter890are used to process the one or more radio frequency signals received by, or to be transmitted by, the antenna unit800. In some embodiments, the embedded processor880executes software modules for controlling the antenna unit800. In some embodiments, the embedded processor880provides instructions to one or more of the antenna circuit chip130and the phase shifter and/or time delay chip including digital beamformers840. In some embodiments, the embedded processor880receives and processes data received via the one or more ports (e.g., SAMTEC stacker230and MMSP240).

The heat sink250is configured to absorb and dissipate heat from one or more components of the antenna unit800. For example, the heat sink250can transfer heat from antenna circuit chip130, the embedded processor880, the phase shifter and/or time delay chip including digital beamformers840, and/or other electrical components. In some embodiments, the heat absorbed by the heat sink250is dissipated by air convection. In some embodiments, the heat sink250is liquid cooled via a cooling fluid (such as water, refrigerants, water/ethylene glycol mixtures, or other coolants known in the art). In some embodiments, the cooling fluid enters via one or more fluid cooling inlets850a/850band exits via a fluid cooling outlet860. In some embodiments, the heat sink250is comprised of aluminum, copper, and/or other materials with sufficient thermal conductivity.

FIG.9is a partially transparent bottom view of an antenna unit, in accordance with some embodiments. A bottom view900shows the heat sink250, fluid cooling inlets850aand850b,fluid cooling outlet860, cold fluid channels910integrated in the heat sink250, the fluid cooling chamber920disposed in proximity to the antenna circuit chip130(FIG.1), and a hot fluid channels930in the heat sink250. The fluid cooling inlets850aand850bare fluidically coupled to the cold fluid channels910within the heat sink250and the cold fluid channels910are fluidically coupled to the fluid cooling chamber920. The fluid cooling chamber920may also be fluidically coupled to the hot fluid channels930and the fluid cooling outlet860. In some embodiments, the cold fluid channels910and/or hot fluid channels930may have diameters of approximately1000micrometers or less.

Cooling fluid enters from either or both of the fluid cooling inlets850aand850band moves towards the fluid cooling chamber920, such as via the cold fluid channels910. In the fluid cooling chamber920, heat generated from at least the antenna circuit chip130is transferred to the cooling fluid. As a result, the heat from the antenna circuit chip130is dissipated resulting in a cooler temperature for the antenna circuit chip, and the temperature of the cooling fluid is increased based on the amount of heat dissipated from the antenna circuit chip130. The heated cooling fluid further moves from the fluid cooling chamber920to the hot fluid channels930within the heat sink250and exits via the fluid cooling outlet860. In some embodiments, the fluid cooling inlets850aand850band fluid cooling outlet860are coupled to one or more pumps (not shown) that promote flow of the cooling fluid via the antenna unit800. In some embodiments, the fluid cooling inlets850aand850band fluid cooling outlet860are coupled to a fluid network (e.g., an open or closed liquid loop) that keeps the cooling fluid moving to and through one or more fluidically coupled antenna units800. In some embodiments, the pumps and/or the fluid network are part of an antenna array100. In some embodiments, the antenna unit800can be quickly coupled to and decoupled from the fluid network and/or pumps via fluid switching couplers.

FIG.10is a partially transparent bottom perspective view of a thermal management system1000of an antenna unit120, in accordance with some embodiments. The thermal management system1000includes the heat sink250, fluid cooling inlets850aand850b,fluid cooling outlet860, cold fluid channels910, the fluid cooling chamber920disposed in proximity to the antenna circuit chip130or any other heat-generating components, and hot fluid channels930within the heat sink250. Although the examples inFIGS.9and10show the antenna circuit chip130being cooled, other heat-generating components (e.g., the embedded processor880) as described inFIG.8can be cooled by the cooling fluid as well.

FIGS.11A and11Bare front side and back side perspective views of an antenna tile1100, in accordance with some embodiments, respectively. The antenna tile110are tessellated with three antenna units120each having a respective thermal management system1000. The antenna tile1110can be an instance of the antenna tile110described above with reference toFIGS.1-3B. Referring toFIG.11B, the one or one or more ports of each antenna unit800is exposed and left unobstructed. Additionally, the fluid cooling inlets850aand850band fluid cooling outlet860of each antenna unit800are also left unobstructed. Each antenna unit800can be individually or jointly liquid cooled (via their respective fluid cooling inlets850aand850band fluid cooling outlet860).

Each antenna unit800can be individually controlled (via the one or more ports). In some embodiments, the one or more antenna units800of an antenna tile1110are configured to operate in conjunction with one another (producing a desired result at the antenna tile1110as a whole). In some embodiments, an antenna tile1110is individually controlled (via its respective one or more antenna units800), independently from any other antenna tiles1110. In some embodiments, an antenna tile1110is jointly controlled (via its respective one or more antenna units800) with one or more other antenna tiles1110. In an example, the antenna array100includes a phased antenna array, and the antenna tiles1110in the phased antenna array are controlled jointly with correlated phases to create a steerable beam of radio waves pointing in different directions without moving the antenna array100.

FIGS.12A and12Bare front side and back side perspective views of an antenna array1200, in accordance with some embodiments, respectively. The antenna array1200is tessellated with the antenna tiles1100each including a plurality of antenna units120. The antenna unit120is the minimum structure that is repeated in the antenna array, and optionally has a thermal management system1000. The tessellated antenna tiles1110of the antenna array1200are similar to the tessellated antenna tiles110shown inFIG.3A and3B. For example, the tessellated antenna tiles1110form the antenna array100(FIG.1) and perform one or more of the features described above with reference toFIGS.1-7.

FIG.13illustrates alternative configurations1302-1310of the antenna units120of an antenna tile110, in accordance with some embodiments. The antenna tile110has a concave hexagon shape or a convex hexagon shape. The antenna units (e.g. antenna units120and800) can be different shapes and sizes. Each antenna unit can be substantially identical, identical, or different. The antenna units120are configured to be tessellated with one another to form an antenna tile110.FIG.13provides examples of different shaped antenna units such as pentagons, trapezoids, kites, diamonds, rhombuses. Each of the antenna units shown inFIG.13are configured to perform the features described above inFIGS.1-12.

In some embodiments, the antenna units120includes three identical rhombuses that closely fit into and fill an antenna tile1302or1306having a convex and equilateral hexagon shape. Each rhombus in the antenna tiles1302and1304includes a first angle overlapping a center of the antenna tile110and a second angle opposite the first angle. In the rhombus in the antenna tile1302, the antenna circuit chip130has two opposite sides facing the first and second angles of the rhombus, respectively. In the rhombus in the antenna tile1306, the antenna circuit chip130has two opposite corners pointing to the first and second angles of the rhombus, respectively. Alternatively, in some embodiments, the antenna units120include three identical pentagons that closely fit into and fill an antenna tile1304having a convex and equilateral hexagon shape. Alternatively, in some embodiments, the antenna units120in the same tile110can be different. For instance, the antenna tile1310has a concave and equilateral hexagon shape. A first antenna unit120has a kite shape and two other antenna units are trapezoids that closely fit into and fill the antenna tile1310with the kite shape. The kite shaped antenna unit120and the two trapezoid shaped antenna units120optionally have equal areas. In another example, the antenna units120includes three pentagons that closely fit into and fill an antenna tile1308and have at least two different pentagonal shapes. The antenna tile1308has a convex and equilateral hexagon shape and is stretched in a direction, so the antenna tile1308is not regular.

FIG.14illustrates configurations of antenna circuit chips130or antenna elements of each antenna unit, in accordance with some embodiments.FIGS.1-13refer to a square antenna circuit chip130, while any different type of antenna circuit chip130can be used to generate the desired results. In some embodiments, geometric parameters of the antenna circuit chip130need be determined based on a desired operational frequency or frequency band of the antenna unit120. In some embodiments, a shape of the antenna circuit chip130is limited to a square or rectangular shape, and however, locations to couple the antenna elements are adjusted based on the desired operational frequency or frequency band of the antenna unit120. A shape of each antenna element is selected from the shapes shown inFIG.14, and an orientation and geometric sizes are determined based on electrical performance of the antenna unit120.

FIG.15illustrates an example configuration of an antenna array1500configured for multi-frequency band operations. As discussed with respect toFIGS.2A-CandFIGS.3A-B, the configuration of antenna units (e.g., the length of the side of the antenna circuit chip, side length, etc.) may determine the operational frequency range for the antenna unit. As such, an antenna tile which includes one or more antenna units, also is configured to operate at a particular frequency range, such as at one of X-Band, Ku-Band, K-Band, Ka-Band, V-Band, or W-Band. In some instances, it may be desirable for an antenna array to include antenna tiles configured to operate at different frequency ranges. In some embodiments, each antenna unit is attached to a common antenna board and/or heat sink.

The antenna array1500illustrates an example antenna array configuration for multi-frequency band operations. The antenna array1500includes two or more antenna tiles, each configured to operate at a particular frequency range. In particular, the antenna array includes one or more antenna tiles1501configured to operate at X-Band frequencies, one or more antenna tiles1502configured to operate at K-Band frequency range, one or more antenna tiles1503configured to operate at Ka-Band frequency range, and/or one or more antenna tiles1504configured to operate at W-Band frequency range. In the particular antenna array configuration1500, each of the one or more antenna tiles corresponding to an operating frequency range are grouped together in a particular operating frequency range section. For example, all of the antenna tiles1501configured to operate at X-Band frequencies are grouped in an X-Band frequency range section such while all antenna tiles1502configured to operate at K-Band frequencies are grouped in a K-Band frequency range section.

In some embodiments, the antenna array1500may include gaps between antenna tiles configured to operate at different frequencies. These gaps may be sized such that a single antenna unit may be inserted into the gap such that the gap is closed. However, it should be appreciated that as the one or more antenna tiles and/or antenna units are configured to operate independently, such gaps will not interfere with the performance of the antenna array.

FIG.16illustrates an example alternative configuration of an antenna array1600configured for multi-frequency band operations. Similar to the antenna array1500, the antenna array1600includes one or more antenna tiles1601configured to operate at X-Band frequencies, one or more antenna tiles1602_aand1602_bconfigured to operate at Ku-Band frequencies, one or more antenna tiles1603_aand1602_bconfigured to operate at Ka-Band frequencies, and/or one or more antenna tiles configured to operate at W-Band frequencies (not shown). The antenna array configuration1600illustrates a configuration where the one or more antenna tiles corresponding to an operating frequency range are interspersed with one another. For example, the antenna tiles1602_aand1602_bconfigured to operate at Ku-Band frequencies are separated from one another. Further, the antenna tiles1602_aand1602_bare interspersed between antenna tiles1601configured to operate at X-Band frequencies and antenna tiles1603_aand1603_bconfigured to operate at Ka-Band frequencies. As another example, antenna tiles1603_aand1603_bconfigured to operate at Ka-Band frequencies are separated from one another. Further, the antenna tiles1603_aand1603_bare interspersed between antenna tiles1601configured to operate at X-Band frequencies and antenna tiles1602_aand1602_bconfigured to operate at Ku-Band frequencies. Such an interspersed antenna array configuration may be advantageous for large antenna arrays as the inclusion of antenna tiles configured for different frequency bands may allow for antenna array gains equivalent to antenna gains yielded from a large aperture.

FIG.17illustrates an example configuration an antenna array1700with a central opening1701. In some example embodiments, an antenna array1700may be formed such that a central opening1701is formed in the center of the antenna array1700. Such a configuration may allow for compact and efficient inclusion of antenna tiles, which may perform similar functions of other antenna array configurations (e.g., antenna array configurations as illustrated inFIGS.1-3B and11A-12B), while reducing the bulkiness of the antenna array. Furthermore, advantageously the antenna array1700may be lighter weight than other antenna array configurations. In some embodiments, the central opening1701may allow for the inclusion of one or more sensors, such as one or more multi-mode sensors, within the central opening1701of the antenna array1700. The one or more sensors may include, but are not limited to, one or more image capturing devices (e.g., cameras, video recording devices, and/or the like). As such, the inclusion of one or more sensors may allow for correlation between time coincident radio frequencies and visible environmental imagery as obtained via the one or more image capturing devices.

FIG.18illustrates a flow diagram of a method for forming an antenna array, in accordance with some embodiments. At operation1802, the method includes providing one or more antenna units (e.g., antenna units120and800described above with reference toFIGS.1-2B and8-10). In some embodiments, each antenna unit120can operate standalone. In other words, each antenna unit120can be coupled to a power and control port (e.g., SAMTEC stacker230) or a radio frequency (RF) port (e.g. MMSP (MicroMode)240) and controlled to operate in the desired frequency or frequency band.

The operation1804, the method1800further includes forming one or more discrete antenna tiles (e.g., antenna tiles110described above with reference toFIGS.1-12) from the one or more antenna units120. In particular, as described above, the one or more discrete antenna tiles110are formed from tessellated antenna units120. In some embodiments, each antenna unit120of a discrete antenna tile110can be replaced in case an individual antenna unit is damaged or malfunctioning, needs repair, needs maintained, etc. The one or more antenna units120forming discrete antenna tiles110work jointly to generate an overall result for an antenna array100. For example, at least three antenna units120are tessellated together to form each of the antenna tiles110that operate jointly with one another. In some embodiments, each antenna tile110operates in one of the X-Band, Ku-Band, K-Band, Ka-Band, or W-Band frequency ranges.

At operation1806, the method1800further includes forming an antenna array100(FIG.1) from the one or more antenna tiles110. In particular, as described above, the one or more discrete antenna tiles110are formed from tessellated antenna units120. In some embodiments, the antenna array100operates in the X, Ku, K, Ka, or W-Bands. In some embodiments, the antenna array100provides an antenna plane. The one or more discrete antenna tiles110and/or the one or more antenna units120are optionally coupled to the antenna plane.

In an aspect of this application, an antenna100includes an antenna unit120having a polygon shape (e.g., a pentagon shape and a rhombus shape) that is configured to form the basis of a monohedral tiling arrangement of identical antenna units. In some embodiments, the antenna unit120has a convex polygon shape. In some embodiments, the antenna unit120has a concave polygon shape. In some embodiments, the antenna unit120is a single antenna unit. In some embodiments (FIG.2C), the antenna unit120is a first antenna unit120a,and the antenna further includes one or more antenna units120bor120csubstantially identical to the first antenna unit120a.In some embodiments, the antenna tile110further includes antenna units120that are tessellated with one another so as to form discrete antenna tiles110. In some embodiments, the antenna array100further includes antenna tiles110that are tessellated with one another.

In the antenna array100, the antenna tiles110are disposed close to one another without leaving an unfilled open area (e.g., greater than a threshold size) between any adjacent antenna tiles110and on a footprint of the antenna array100. In some embodiments, each antenna tile110only includes three antenna units120a-120cthat fit into and fill the antenna tile110, i.e., without leaving an unfilled open area (e.g., greater than a threshold size) on the antenna tile110. Each antenna unit120is a smallest unit that is repeated in the antenna array100, and has a number of sides less than six. In some embodiments, the number of sides of each antenna unit120is more than 3. For example, the number of sides of each antenna unit120is specifically 4 (rhombus) or 5 (pentagon). That said, in some embodiments, each antenna tile110of a hexagon shape is made of rhombus-shaped or pentagon-shaped antenna unit120.

In some embodiments, each antenna tile110includes a plurality of antenna units120a-120cthat have the same size and different orientations with respect to a center or side of the antenna tile110. The antenna circuit chips130are disposed at the same location with the same orientation on the antenna units120. However, given the different orientations of the antenna units120in the antenna tile110, the antenna circuit chips130in the antenna units120are also oriented differently with respect to a center or side of the antenna tile110.