Horn antenna and lens for horn antenna

Abstract

A lens for a horn antenna and a horn antenna including the lens. The lens includes a generally horn-shaped plate assembly extending generally along an axis from a first side to a second side opposite the first side. The generally horn-shaped plate assembly defines a plurality of nonlinear channels. The plurality of nonlinear channels are operable to manipulate electromagnetic waves received at the first side and provide manipulated electromagnetic waves at the second side. The plurality of nonlinear channels can affect the amplitude and / or phase distribution of the electromagnetic field transmitted through the lens.

Description

Technical Field

[0001] The invention relates to a horn antenna and a lens used for the horn antenna.

[0002] Background Field

[0003] With the rapid development of wireless communication technology, broadband high-gain antennas have attracted people's attention. At present, there are methods for manufacturing broadband high-gain antennas. However, these existing methods usually lead to one or more of the following undesirable problems: bulky antenna structure, complex antenna design / construction, limited gain bandwidth and high manufacturing cost, etc. Summary of the invention

[0004] In a first aspect, a lens for a horn antenna is provided. The lens includes a generally flared plate assembly extending generally along an axis from a first side to a second side opposite to the first side. The generally flared plate assembly defines a plurality of nonlinear channels that are operable to manipulate electromagnetic waves received on the first side and provide (radiate) manipulated electromagnetic waves on the second side. Optionally, the plurality of nonlinear channels are arranged so that the manipulated electromagnetic waves on the second side include quasi-plane wavefronts. For example, the plurality of nonlinear channels are arranged so that: when the electromagnetic waves received on the first side include quasi-plane wavefronts, the manipulated electromagnetic waves on the second side include quasi-plane wavefronts. In such an example, the electric field (E field) of the electromagnetic wave received on the first side may be generally perpendicular to the axis. In such an example, the electromagnetic wave received on the first side may be a y-polarized electromagnetic wave.

[0005] Optionally, the plurality of nonlinear channels are arranged substantially symmetrically with respect to an axis, wherein the axis serves as a line of reflection symmetry.

[0006] Optionally, each of the plurality of nonlinear channels comprises: a first opening located on a first side and a second opening located on a second side, and the width of the first opening defined perpendicular to the axis is smaller than the width of the second opening defined perpendicular to the axis. The first openings of different nonlinear channels may have the same width or different widths. The second openings of different nonlinear channels may have the same width or different widths. In one example, each first opening is used as an electromagnetic wave entrance and each second opening is used as an electromagnetic wave exit. In another example, each first opening is used as an electromagnetic wave exit and each second opening is used as an electromagnetic wave entrance.

[0007] Optionally, the plurality of nonlinear channels includes or has only a first plurality of nonlinear channels arranged on one side of the axis and a second plurality of nonlinear channels arranged on the other side of the axis. The first plurality of nonlinear channels and the second plurality of nonlinear channels may have the same number of channels. In one example, the first plurality of nonlinear channels and the second plurality of nonlinear channels are generally symmetrically arranged with respect to the axis, and thus, the axis acts as a line of reflection symmetry (i.e., the first plurality of nonlinear channels and the second plurality of nonlinear channels are mirror images of each other with respect to the axis).

[0008] Optionally, for each nonlinear channel in the first plurality of nonlinear channels, the center of the first opening and the center of the second opening may be connected by a straight line, the straight line extending at a non-zero angle (e.g., an acute angle) relative to the axis. In addition, the straight lines of the first plurality of nonlinear channels are arranged at different angles relative to the axis, such that the straight lines associated with the nonlinear channels closer to the axis are at a smaller angle (e.g., an acute angle) relative to the axis and the straight lines associated with the nonlinear channels farther from the axis are at a larger angle (e.g., an acute angle) relative to the axis.

[0009] Optionally, for each nonlinear channel in the second plurality of nonlinear channels, the center of the first opening and the center of the second opening may be connected by a straight line, the straight line extending at a non-zero angle (e.g., an acute angle) relative to the axis. In addition, the straight lines of the second plurality of nonlinear channels are arranged at different angles relative to the axis, such that the straight lines associated with the nonlinear channels closer to the axis are at a smaller angle (e.g., an acute angle) relative to the axis and the straight lines associated with the nonlinear channels farther from the axis are at a larger angle (e.g., an acute angle) relative to the axis.

[0010] Optionally, the generally flared plate assembly includes a plurality of plates defining a plurality of nonlinear channels, and the plurality of plates include: a first plate extending at a non-zero angle (e.g., an acute angle) relative to the axis, a second plate extending at a non-zero angle (e.g., an acute angle) relative to the axis, and a plurality of intermediate plates arranged between the first plate and the second plate. Optionally, the first plate and the second plate together define a first width perpendicular to the axis on a first side and a second width perpendicular to the axis on a second side, wherein the first width is less than the second width. Each nonlinear channel may be defined between corresponding adjacent plates. The first plate may be an end plate. The second plate may be an end plate.

[0011] Optionally, the plurality of plates of the generally flared plate assembly are generally symmetrical about an axis, wherein the axis serves as a line of reflected symmetry.

[0012] Optionally, each of the plurality of intermediate plates includes: a first end arranged on the first side, a second end arranged on the second side, a first surface extending between the first end and the second end, and a second surface opposite to the first surface and extending between the first end and the second end.

[0013] Optionally, the first surface of one or more or each of the plurality of intermediate plates comprises or has only a wavy or serrated surface.

[0014] Optionally, the second surface of one or more or each of the plurality of intermediate plates comprises or has only a wavy or serrated surface.

[0015] Optionally, for at least some of the plurality of intermediate plates, the wavy surface of the same intermediate plate has substantially the same wavy shape.

[0016] Optionally, for at least some of the plurality of intermediate plates, the wavy surfaces of different intermediate plates have different wavy shapes.

[0017] Optionally, the wavy surface is represented by a cosine-based function f n (u) = a n cos(ω n u) is defined, where n is the identifier of the intermediate board, a n is the amplitude, ω n is the angular frequency. Different wavy surfaces and / or wavy shapes may have different amplitudes and / or angular frequencies.

[0018] Optionally, the first plate includes: a first end arranged on the first side, a second end arranged on the second side, a first surface extending between the first end and the second end, and a second surface opposite to the first surface and extending between the first end and the second end. Optionally, the first surface of the first plate is a substantially flat surface.

[0019] Optionally, the second surface of the first plate is a substantially flat surface.

[0020] Optionally, the second plate includes: a first end arranged on the first side, a second end arranged on the second side, a first surface extending between the first end and the second end, and a second surface opposite to the first surface and extending between the first end and the second end. Optionally, the first surface of the second plate is a substantially flat surface.

[0021] Optionally, the second surface of the second plate is a substantially flat surface.

[0022] Optionally, the first ends of the plurality of intermediate plates (and optionally the first end of the first plate and / or the first end of the second plate) are arranged in substantially the same plane, which is arranged substantially perpendicular to the axis.

[0023] Optionally, the second ends of the plurality of intermediate plates (and optionally the second end of the first plate and / or the second end of the second plate) are arranged in substantially the same plane, which is arranged substantially perpendicular to the axis.

[0024] Optionally, for each respective intermediate plate of the plurality of intermediate plates, the first end and the second end are substantially parallel.

[0025] Optionally, the first ends of the plurality of intermediate plates (and optionally the first end of the first plate and / or the first end of the second plate) extend substantially perpendicular to the axis.

[0026] Optionally, the second ends of the plurality of intermediate plates (and optionally the second end of the first plate and / or the second end of the second plate) extend substantially perpendicular to the axis.

[0027] Optionally, the first ends of the plurality of intermediate plates are arranged in substantially the same first plane, which is arranged substantially perpendicular to the axis; the second ends of the plurality of intermediate plates are arranged in substantially the same second plane, which is arranged substantially perpendicular to the axis; and the first plane and the second plane are substantially parallel.

[0028] Optionally, each of the plurality of intermediate plates further includes: a third end extending between the first end and the second end of the corresponding intermediate plate, and a fourth end opposite to the third end and extending between the first end and the second end of the corresponding intermediate plate.

[0029] Optionally, the first plate further includes: a third end extending between the first end and the second end of the first plate, and a fourth end opposite to the third end and extending between the first end and the second end of the first plate.

[0030] Optionally, the second plate further includes: a third end extending between the first end and the second end of the second plate, and a fourth end opposite to the third end and extending between the first end and the second end of the second plate.

[0031] Optionally, for each respective intermediate plate of the plurality of intermediate plates, the third end and the fourth end are substantially parallel.

[0032] Optionally, the third ends of the plurality of intermediate plates (and optionally the third end of the first plate and / or the third end of the second plate) are arranged in substantially the same plane, which is substantially parallel to the axis.

[0033] Optionally, the fourth ends of the plurality of intermediate plates (and optionally the fourth end of the first plate and / or the fourth end of the second plate) are arranged in substantially the same plane, which is substantially parallel to the axis.

[0034] Optionally, the third ends of the plurality of intermediate plates are arranged in substantially the same first plane, which is substantially parallel to the axis; the fourth ends of the plurality of intermediate plates are arranged in substantially the same second plane, which is substantially parallel to the axis; and the first plane and the second plane are substantially parallel.

[0035] Optionally, for each of the plurality of intermediate plates (and optionally the first plate and / or the second plate), the distance between the third end and the fourth end defines a height of the intermediate plate. The height of one or more or all of the intermediate plates may be substantially constant. The height of the first plate and / or the height of the second plate may be substantially constant. The height of the intermediate plates (and optionally the height of the first plate and / or the height of the second plate) may be substantially the same.

[0036] Optionally, the first surface of each of the plurality of intermediate plates (and optionally the first surface of the first plate and the first surface of the second plate) is a metal surface. Optionally, the second surface of each of the plurality of intermediate plates (and optionally the second surface of the first plate and the second surface of the second plate) is a metal surface.

[0037] Optionally, the plurality of plates are made entirely of metal. Optionally, the plurality of plates are additively manufactured.

[0038] Optionally, the plurality of intermediate plates (and optionally the first plate and / or the second plate) are made completely of metal.

[0039] Optionally, the plurality of intermediate plates (and optionally the first plate and / or the second plate) are additively manufactured.

[0040] Optionally, the lens also includes a support for supporting the generally flared plate assembly (e.g., multiple intermediate plates (and optionally the first plate and / or the second plate)) in an appropriate position. The support may include a mount, a coupler, a bracket, a frame, a fastener, a housing, an adhesive, etc. The support may or may not be symmetrical about the axis.

[0041] Optionally, the generally flared plate assembly defines an envelope that is generally in the shape of a trapezoidal prism having an upper base (short base) on a first side and a lower base (long base) on a second side.

[0042] In one example, the lens is only suitable for horn antennas. In one example, the lens is particularly (but not limited to) suitable for horn antennas.

[0043] In a second aspect, a horn antenna is provided. The horn antenna comprises the lens of the first aspect and a power divider assembly operably connected to the lens. The power divider assembly can be directly connected to the lens (i.e., there is no intermediate component between the power divider assembly and the lens). The horn antenna can be used to receive and / or transmit electromagnetic waves. The horn antenna can be a broadband high-gain antenna. In one embodiment, the power divider assembly can be used to distribute power evenly or equally. In another embodiment, the power divider assembly can be used to distribute power unevenly or unequally.

[0044] Optionally, the power divider assembly is a proportional power divider assembly arranged to divide the power of the electromagnetic waves substantially equally.

[0045] Optionally, the power divider assembly is a different ratio power divider assembly arranged to unequally divide the power of the electromagnetic wave.

[0046] Optionally, the horn antenna further comprises a flange for connecting with the waveguide. The flange is operably connected with the power divider assembly and is opposite to the lens.

[0047] Optionally, the horn antenna further includes a waveguide connected to the flange.

[0048] Optionally, the power divider assembly comprises one or more power dividers arranged to manipulate electromagnetic waves from the feed source and to provide the manipulated electromagnetic waves to the lens.The power divider assembly is arranged to manipulate at least the magnitude of the electromagnetic waves.

[0049] Optionally, the power divider assembly is made entirely of metal.

[0050] Optionally, the power divider assembly is additively manufactured.

[0051] Alternatively, the power divider assembly and the lens extend generally along the axis of the generally trumpet-shaped plate assembly. The lens can define a first height perpendicular to the axis and the power divider assembly can define a second height perpendicular to the axis. The first height and the second height can be different or can be substantially the same. The power divider assembly and the lens can be arranged so that the axis divides the first height and / or the second height equally.

[0052] Optionally, the power divider assembly and the lens extend generally along the axis of the generally flared plate assembly. The lens may define a first height perpendicular to the axis. The power divider assembly may include: a first portion having a second height less than the first height and perpendicular to the axis, and a second portion transitioning from the first portion to the lens. The power divider assembly and the lens may be arranged so that the axis bisects the first height and / or the second height. The transition of the second portion may be curved or linear. The second portion may be a generally flared portion that flares along the axis and is generally perpendicular to the flaring of the generally flared plate assembly along the axis.

[0053] By considering the detailed description and the accompanying drawings, other features and aspects of the present invention will become apparent. Where appropriate and applicable, any one or more features described herein for one aspect or embodiment may be combined with any one or more other features described herein for any one or more other aspects or embodiments.

[0054] Terms of degree or relative terms (e.g., "generally," "approximately," "about," "substantially," etc.) related to quantities or conditions are used to take into account (depending on the context) at least one of the following: manufacturing tolerances, degradation, assembly, usage, trends, tendencies, practical applications, etc. In some examples, when used with numerical values, relative terms can include the indicated value and plus or minus a percentage (e.g., 1%, 5%, 10%, 15%, or 20%) thereof.

[0055] As used herein, the expression "generally flared" refers to a tendency to expand (or widen), which includes strictly (continuously) expanding, monotonically expanding, or overall expanding (i.e., there may be narrowing during the expansion process). As used herein, the expressions "generally parallel" and "generally perpendicular" are intended to indicate that strict parallelism and strict perpendicularity are not required. As used herein, the expression "generally symmetrical" is intended to indicate that strict symmetry is not required.

[0056] As used herein, the feature "plate" refers generally to a plate-like structure, and is not intended to limit the structure to a particular thickness or flatness.

[0057] Unless stated otherwise, the terms "connected," "coupled," "coupled," "mounted," etc., are intended to cover both direct and indirect connections, couplings, couplings, mountings, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0058] Embodiments of the present invention will now be described by way of example with reference to the accompanying drawings, in which:

[0059] Figure 1A is a perspective view of a lens for a horn antenna according to one embodiment of the present invention;

[0060] Figure 1B yes Figure 1A Schematic diagram of the lens;

[0061] Figure 2A is a schematic diagram of the operation of a horn antenna with a conventional lens;

[0062] Figure 2B Is has Figure 1A Schematic diagram of the operation of the lens horn antenna;

[0063] Figure 3A A horn antenna (combined with Figure 1A perspective view of a lens);

[0064] Figure 3B yes Figure 3A Schematic diagram of a power divider assembly of a horn antenna (top view);

[0065] Figure 3C yes Figure 3A Schematic diagram of the lens of the horn antenna (top view);

[0066] Figure 3D yes Figure 3A Schematic diagram of the horn antenna (side view);

[0067] Figure 4A is a graph showing the simulated (normalized) electric field distribution of a conventional horn antenna (reference) at 15 GHz;

[0068] Figure 4B is shown at 15GHz Figure 3A A graph of the simulated (normalized) electric field distribution of the horn antenna;

[0069] Figure 5 is a graph showing simulated electric field phase distribution along the aperture of a conventional horn antenna (reference) and a horn antenna according to one embodiment of the present invention at 15 GHz;

[0070] Figure 6 It is shown Figure 3A Schematic diagram of the corresponding dimensions (axial length and aperture size) of the horn antenna, the conventional horn antenna (reference) and the optimal horn antenna (reference-optimized);

[0071] Figure 7 It shows the difference in frequency (GHz) Figure 3A Horn antenna, traditional horn antenna (reference) and Figure 6 The simulation results of the optimal horn antenna (reference-optimization) in the simulation achieve the gain (at θ = 0 0 )

[0072] Fig. 8A yes Figure 6 Schematic diagram of the optimal horn antenna;

[0073] Figure 8B yes Figure 3A Schematic diagram of the horn antenna;

[0074] Figure 8C is a graph showing the simulated (normalized) electric field distribution at the aperture of the optimal horn antenna at 15 GHz;

[0075] Fig.8D is a diagram showing a simulated (normalized) electric field distribution at the aperture of a horn antenna according to one embodiment of the present invention at 15 GHz;

[0076] Fig. 9A This is a horn antenna prototype of an embodiment of the present invention (based on Figure 3A Horn antenna production; Photograph before electroplating (perspective view);

[0077] Fig. 9B yes Fig. 9A Photo of the horn antenna prototype (after electroplating) (top view);

[0078] Fig. 9C yes Fig. 9A Photo of the horn antenna prototype (after electroplating) (perspective view);

[0079] Fig. 10A It is shown at different frequencies (GHz) Fig. 9C Measurement and simulation of the reflection coefficient of the horn antenna (|S 11 |)’s curve graph;

[0080] Fig. 10B It is shown at different frequencies (GHz) Fig. 9C The measured and simulated gain of the horn antenna (at θ = 0 0 )

[0081] Fig.11A It is shown Fig. 9C Graphs of measured and simulated (normalized) radiation patterns of the horn antenna in the E-plane (xy-plane);

[0082] Fig. 11B It is shown Fig. 9C Graphs of measured and simulated (normalized) radiation patterns of the horn antenna in the H plane (xz plane);

[0083] Fig.12 is a schematic diagram (exploded view) of a horn antenna according to one embodiment of the present invention;

[0084] Fig.13A yes Fig.12 Schematic diagram of the power divider assembly of the horn antenna (top view);

[0085] Fig. 13B yes Fig.13A an enlarged view of a portion of a power divider assembly;

[0086] Fig. 13C yes Fig.12 Schematic diagram of the lens of the horn antenna (top view);

[0087] Fig.14 yes Fig.12 Schematic diagram of the horn antenna and Fig.12 A graph of the height profile of the horn antenna;

[0088] Fig.15 Show Fig. 9C Horn antenna and Fig.12Graphs of the height distribution of the horn antennas and their corresponding H-plane radiation patterns at 15 GHz;

[0089] Fig.16 It is shown Fig. 9C Horn antenna and Fig.12 Plot of the measured (normalized) H-plane radiation pattern of the horn antenna;

[0090] Fig.17A is shown at 15GHz Fig. 9C A graph of the simulated (normalized) electric field distribution of the horn antenna;

[0091] Fig. 17B is shown at 15GHz Fig.12 A graph of the simulated (normalized) electric field distribution of the horn antenna;

[0092] Fig.18 It is shown in Fig. 9C The aperture of the horn antenna and Fig.12 A graph of the simulated electric field distribution at the aperture of the horn antenna;

[0093] Fig.19 It is shown Fig. 9C Horn antenna and Fig.12 A graph of the measured (normalized) electric field radiation pattern of the horn antenna;

[0094] Fig. 20 It is shown Fig. 9C Horn antenna and Fig.12 The simulation results of the horn antenna gain (θ=0 0 )

[0095] Fig.21A This is a horn antenna prototype of an embodiment of the present invention (based on Fig.12 Photograph of the horn antenna manufacturing) (top view);

[0096] Fig.21B yes Fig.21A Photo of the horn antenna prototype (perspective view);

[0097] Fig. 22 It is shown Fig.21A Measurement and simulation of the reflection coefficient of the horn antenna (|S 11 |)’s curve graph;

[0098] Fig.23 It is shown Fig.21A Horn antenna and traditional horn antenna (with Fig.21A The measured and simulated gain (at θ = 0) of the horn antenna with the same aperture size, focal length and antenna length) is shown in Figure 2. 0(time) curve graph;

[0099] Fig.24A is shown at 12GHz Fig.21A Graphs of the measured and simulated (normalized) radiation patterns of the horn antenna in the E-plane (xy-plane);

[0100] Fig. 24B is shown at 12GHz Fig.21A Graphs of measured and simulated (normalized) radiation patterns of the horn antenna in the H plane (xz plane);

[0101] Fig.25A is shown at 15GHz Fig.21A Graphs of the measured and simulated (normalized) radiation patterns of the horn antenna in the E-plane (xy-plane);

[0102] Fig.25B is shown at 15GHz Fig.21A Graphs of measured and simulated (normalized) radiation patterns of the horn antenna in the H plane (xz plane);

[0103] Fig.26A is shown at 18 GHz. Fig.21A Graphs of measured and simulated (normalized) radiation patterns in the E-plane (xy-plane) of the horn antenna; and

[0104] Fig.26B is shown at 18 GHz. Fig.21A Plots of the measured and simulated (normalized) radiation patterns of the horn antenna in the H-plane (xz-plane). DETAILED DESCRIPTION

[0105] The present invention generally relates to a lens for a horn antenna and a horn antenna including the lens. The lens includes a generally horn-shaped plate assembly extending along an axis between two sides. The generally horn-shaped plate assembly defines a nonlinear channel, which is operable to manipulate electromagnetic waves received on one side of the generally horn-shaped plate assembly, thereby providing manipulated electromagnetic waves on the other side of the generally horn-shaped plate assembly. In some embodiments, the lens can be an H-plane metal plate lens, which includes a stack of metal plates or metal-coated plates oriented generally parallel to the H plane of the electromagnetic wave (perpendicular to the E plane). Example embodiments of the present invention will be provided below.

[0106] Figure 1AA lens 100 for a horn antenna is shown in accordance with one embodiment of the present invention. Generally, the lens 100 includes a generally horn-shaped plate assembly 102 extending between opposite sides 102F, 102R generally along an axis Z. The generally horn-shaped plate assembly 102 defines a plurality of nonlinear channels C operable to manipulate electromagnetic waves received at one of the two sides 102F, 102R to provide manipulated electromagnetic waves at the other of the two sides 102F, 102R.

[0107] The generally trumpet-shaped plate assembly 102 includes a plurality of plates (i.e., a plate-like structure) defining channels C. In this embodiment, the generally trumpet-shaped plate assembly 102 defines sixteen channels C that are generally symmetrically arranged relative to the axis Z, with eight channels C located on one side of the axis Z and the other eight channels C located on the other side of the axis Z. Each of the sixteen channels C includes an opening on one side 102R and an opening on the other side 102F. In this embodiment, for each corresponding channel C, the width of the opening on the side 102F (in Figure 1A The width of the opening on the side 102R is greater than the width of the opening on the side 102R (defined along the y-axis in the reference system of Figure 1A In addition, in this embodiment, the widths of the different openings of the different channels C located at the side 102F are substantially the same and the widths of the different openings of the different channels C located at the side 102R are substantially the same. Figure 1A and Figure 1B In this embodiment, for each channel C, the center of the opening located at the side 102R and the center of the opening located at the side 102F may be connected by a straight line, which forms a non-zero acute angle with the axis Z. For the eight channels C arranged on one side of the axis Z, the straight lines of the channels C are arranged at different angles relative to the axis Z, so that the angle between the straight line associated with the channel C closer to the axis Z and the axis Z is smaller than the angle between the straight line associated with the channel C farther from the axis Z and the axis Z. Due to the symmetrical nature of the channels C, the same applies to the eight channels C arranged on the other side of the axis Z.

[0108] As described above, the channel C is defined by the plates of the generally flared plate assembly 102. In this embodiment, the generally flared plate assembly 102 includes seventeen plates (only nine of which are Figure 1A These seventeen plates define sixteen channels C, with one channel C between every two adjacent plates. Figure 1AAs shown, the plates include two transverse end plates (one of which is M9) extending at a non-zero angle relative to the axis Z, respectively, and fifteen intermediate plates arranged between the two transverse end plates. The fifteen intermediate plates include a central intermediate plate M1, seven intermediate plates between one of the transverse end plates and the central intermediate plate M1, and seven intermediate plates between the other transverse end plate and the central intermediate plate M1. The two transverse end plates together define a smaller width w2 on the side 102R and a larger width w1 on the side 102F. In this embodiment, the plates of the generally flared plate assembly 102 are generally symmetrical relative to the axis Z. Although not shown, the plates can be fixed in place by a suitable support device, which can include a mechanical device (e.g., a mount, a coupler, a bracket, a frame, a fastener, a housing, an adhesive, etc.).

[0109] like Figure 1A As shown, in this embodiment, each plate of the generally trumpet-shaped plate assembly 102 includes one end located at side 102R, another end located at side 102F, a top end and a bottom end (at Figure 1A A reference system is defined along an axis x) and two opposite surfaces, each of which extends between two ends (on both sides 102R, 102F) and between a top end and a bottom end.

[0110] In this embodiment, both surfaces of each of the fifteen intermediate plates are wavy (corrugated) surfaces. Specifically, for each of the seven intermediate plates located between one transverse end plate and the central intermediate plate M1 and each of the seven intermediate plates located between another transverse end plate and the central intermediate plate M1, the two surfaces of the same intermediate plate are wavy surfaces having substantially the same wavy shape. For the central intermediate plate M1, its two surfaces are wavy surfaces having different (opposite) wavy shapes. In this embodiment, the wavy surface or wavy shape is determined by a cosine-based function f n (u) = a n cos(ω n u) is defined, where n is the identifier of the intermediate board, a n is the amplitude, ω nis the angular frequency. The amplitude and / or angular frequency of each corresponding intermediate plate may be constant or may be variable. In this embodiment, the waviness of the wavy surface of the central intermediate plate M1 is the largest (e.g., the maximum amplitude of the cosine function), while the waviness of the wavy surfaces of the intermediate plates on both sides of the central intermediate plate M1 decreases as they move away from the central intermediate plate M1. In other words, the wavy surface of the intermediate plate M2 has a larger waviness (e.g., the amplitude of the cosine function is larger) than the wavy surface of the intermediate plate M3, the wavy surface of the intermediate plate M3 has a larger waviness (e.g., the amplitude of the cosine function is larger) than the wavy surface of the intermediate plate M4, and so on. The same applies to the plates located on the other side of the axis Z because, in this embodiment, the plates are substantially symmetrical relative to the axis Z. As Figure 1A As shown, in this embodiment, the two surfaces of each of the two lateral end plates are substantially flat surfaces. In this embodiment, the plates of the substantially flared plate assembly 102 can be referred to as metal plates or metal plates, and the lens 100 can be referred to as metal lenses or metal lenses. They can be made entirely of metal (for example, using additive manufacturing (3D printing) methods). Alternatively, they can be made partially of metal, wherein at least two surfaces of each plate (between the top and bottom ends and between the ends of the sides 102R and 102F) are metal surfaces.

[0111] like Figure 1A and Figure 1B As shown, in this embodiment, the ends (eg, end surfaces) of the plates of the generally flared plate assembly 102 at side 102R are arranged in generally the same plane ( Figure 1A The xy plane in the reference system of Figure 1B A in the plane), which is substantially perpendicular to the axis Z. In addition, the ends (e.g., end surfaces) of the plates of the substantially flared plate assembly 102 at the side 102F are also arranged in substantially the same plane ( Figure 1A Another xy plane in the reference frame, Figure 1B The plane B in the figure is generally perpendicular to the axis Z. The ends of each corresponding plate are generally parallel. In addition, as Figure 1A and Figure 1B As shown, in this embodiment, the top ends (eg, end surfaces) of the plates of the generally flared plate assembly 102 are arranged in generally the same plane ( Figure 1A yz plane in the reference system of ), which is parallel to the axis Z. In addition, the bottom ends (eg, end surfaces) of the plates of the generally flared plate assembly 102 are arranged in generally the same plane ( Figure 1A Another yz plane in the reference system of ), which plane is parallel to the axis Z. In this embodiment, each plate has a substantially constant height h (along the Figure 1A The x-axis Z in the reference system of FIG. 1 is defined), and the plates have substantially the same height h. Figure 1A As shown, in this embodiment, side 102R of lens 100 is the entrance of electromagnetic waves, side 102F of lens 100 is the exit of electromagnetic waves, the input (entrance) aperture size of lens 100 is w2×h, and the output (exit) aperture size of lens 100 is w1×h, wherein w1 is greater than w2.

[0112] like Figure 1A As shown, in this embodiment, the generally flared plate assembly 102 defines an envelope that is generally in the shape of a trapezoidal prism having an upper base at side 102R, a lower base at side 102F, and trapezoidal bases at the top and bottom.

[0113] Reference now Figure 1B , the straight line connecting the two ends of the same plate forms an angle φ with the axis Z n In this embodiment, φ n By φ n =cos -1 (D1 / D n ), where D_1 is the linear (direct) distance (i.e., displacement) between the two ends of the central intermediate plate and D n is the linear (direct) distance (i.e. displacement) between the two ends of the nth plate.

[0114] Without loss of generality, the following description provides reference to the board MP n The design of the lens 100 is explained in more detail. As mentioned above, the channels and plates are arranged substantially symmetrically with respect to the axis Z, so only the channels C and plates M1-M9 on one side (but including the central plate M1) are labeled.

[0115] refer to Figure 1B , an incident electromagnetic (EM) wave of y polarization enters the lens at face A (enters at face A of side 102R, passes through lens 100, and exits the lens at face B of side 102F). It should be noted that Figure 1B , the dashed lines showing faces A and B are shown as blocking some openings of the channel of lens 100. In this embodiment, MP n The shape of is based on the cosine function where a n and D n MP n The amplitude and direct distance between the two endpoints of MP. n The length Ln is given by

[0116]

[0117] Theoretically, when L1=L2=L3=…=L9 (where L nis the length of the nth plate), for different channels, electromagnetic waves with the same phase can be obtained on surface B, and by fixing one of the L n (For example, L9 is) to determine different amplitudes a n However, in practice, due to fringe field effects at the aperture of face B, for example, it has been found that it may be necessary to reduce L n Modified to L n ' to improve the phase uniformity of the electromagnetic wave at plane B. In this embodiment, the correction factor c is used n , which is limited to c n =L n ' / L9 (HFSS was used to optimize their values). Table I shows the different MP n The correction factor c n Based on these values, the actual length L for manufacturing can be determined n ′=c n L9. In other words, in this embodiment, different plates MP on the same side n The physical lengths are different and when applying the correction factor c n After that, the phase distribution at the aperture at face B is roughly the same.

[0118] Table I - Correction coefficients for different channels

[0119] <![CDATA[MP n ]]> 1 2 3 4 5 6 7 8 9 <![CDATA[c n ]]> 1.05 1.1 1.25 1.35 1.35 1.25 1.1 1.0 1

[0120] The operating principle of lens 100 will now be described. Figure 2A The working principle of the horn antenna with a conventional lens for the horn antenna (which can be used as an H-plane metal lens) is shown. Figure 2B The working principle of a horn antenna with a lens 100 (which can be used as an H-plane metal lens) is shown. Both antennas receive electromagnetic waves from a point source E.

[0121] like Figure 2A As shown, in a horn antenna with a traditional lens, the electromagnetic wave is confined by linear metal plates of different lengths, where the phase delay of the incident electromagnetic wave is manipulated or controlled by the length of the channel. Therefore, in this design, the length of the channel controls the phase distribution at the output aperture. However, since the phase velocity in the channel is dispersed, the bandwidth of the lens is limited. In addition, due to the asymmetric structure of the channel, the radiation pattern may be undesirable.

[0122] like Figure 2BAs shown, the horn antenna includes a lens 100 and a power divider assembly arranged between the source E and the lens 100. The power divider is operable to manipulate the electromagnetic waves from the source E to produce a quasi-plane wavefront, which is used to input into the lens 100. The details of the power divider assembly will be described below. The lens 100 guides the electromagnetic waves to meander from the input aperture through the lens to the output aperture. The working principle of the lens 100 is based on electromagnetic wave delay, similar to a dielectric lens (so the lens 100 can be considered as a delay lens). For the lens 100, a plane electromagnetic wave is received at a smaller aperture on the input side, which is manipulated by the lens 100 (channel and plate), and then the plane electromagnetic wave is output at a larger aperture on the output side. This transformation is achieved by a nonlinear channel in the lens 100. In the sine function f n (x) with different amplitudes a n In the case of , the total physical length of the channel can be arranged to provide a broadband substantially constant phase at the output aperture.

[0123] The lens 100 design has advantages over conventional designs. First, the lens 100 is less sensitive to frequency variations, so a lens with a wider frequency band can be obtained. In addition, a more symmetrical radiation pattern can be produced. Third, because the lens 100 is integrated with the horn (i.e., not outside the horn), the antenna design with the lens 100 is more compact.

[0124] FIG. 3A to FIG. 3D A horn antenna 300 in one embodiment is shown. In this embodiment, the horn antenna 300 is a high gain antenna having a substantially uniform amplitude distribution at its exit aperture. The horn antenna 300 includes a flange 302 for connecting to a waveguide, a power divider assembly 304 connected to the flange 302, and a metal lens 306 (having the same design as the lens 100) connected to the power divider assembly 304. The antenna 300 also includes a retaining bar 308 for holding or supporting the power divider assembly 304 and the lens 306 in place. As described herein, the antenna 300 is also referred to as "antenna 1".

[0125] Figure 3A The overall design of antenna 300 is shown. Figure 3B The flange 302 and the power divider assembly 304 are shown. In this embodiment, the flange 302 is made of metal and is arranged to align with the standard waveguide WG18 (15.799×7.899 mm 2 ) connection. Flange 302 includes an opening leading to power divider assembly 304 (eg Figure 3A), so that the electromagnetic waves received from the waveguide can be provided to the power divider assembly 304. In this embodiment, the power divider assembly 304 is also made of metal (e.g., a metal plate). The power divider assembly 304 includes a central channel portion, two channel portions branching from the central channel portion and symmetrically arranged relative to a symmetry axis (e.g., parallel to or colinear with the axis Z), and two power dividers 304P1, 304P2 at the outlet of each of the two branch channel portions. Due to the presence of the power dividers 304P1, 304P2, the two channel portions are further branched into four channel portions, which are connected to the lens. As shown Figure 3B As shown, the front end or edge of each power divider 304P1, 304P2 has a respective offset s0 away from the axis of symmetry and relative to the centerline of a respective one of the two channel portions to help obtain a substantially uniform amplitude distribution of the electromagnetic wave.

[0126] Figure 3C A lens 306 is shown which is generally identical to lens 100 and will not be described again. Figure 3D The antenna 300 is shown as viewed from one side. It can be seen that the power splitter assembly 304 and the lens 306 (specifically the plate of the lens 306) are substantially the same height.

[0127] Table II shows the parameter values ​​of antenna 300 optimized using HFSS. In this example, unless otherwise stated, the design parameters of the lens are the same as the design parameters of lens 100. In Table II, thickness refers to the thickness of the plate of lens 306.

[0128] Table II - Parameters of Antenna 300

[0129] Flange <![CDATA[l0]]> <![CDATA[l1]]> <![CDATA[l2]]> <![CDATA[l3]]> s <![CDATA[s0]]> d 40.0mm 3.5mm 3.0mm 12.0mm 3.0mm 7.9mm 2.0mm 19.4mm <![CDATA[d0]]> <![CDATA[d 01 ]]> <![CDATA[w0]]> <![CDATA[w1]]> <![CDATA[w2]]> <![CDATA[h1]]> θ thickness 2.0mm 3.0mm 1.0mm 106.0mm 59.7mm 15.8mm 60° 0.6mm

[0130] To demonstrate the phase correction capability of antenna 300 (compared to a conventional horn antenna), simulations were performed.

[0131] Figure 4A shows the simulated (normalized) electric field distribution in a conventional horn antenna (reference) at 15 GHz, while Figure 4B shows that at 15 GHz Figure 3A Simulated (normalized) electric field distribution in the horn antenna 300. In this simulation, the conventional horn antenna and the antenna 300 have the same length along the symmetry axis. Figure 4A and Figure 4B As shown, a conventional horn has a curved wavefront at the radiation aperture (exit), whereas antenna 300 has a relatively straight wavefront at the radiation aperture (exit) due at least to the presence of lens 306 (eg, as an H-plane metallic lens).

[0132] Figure 5 FIG. 3 shows the simulated electric field phase distribution of the conventional horn antenna and the antenna 300 along the radiation aperture (exit) at 15 GHz. Figure 5 As shown, the overall phase variation of the antenna 300 is much smaller than that of the reference horn antenna.

[0133] In theory, and generally speaking, the directivity of an aperture antenna is greatest when the field across the aperture (exit) is uniform. Figure 6 The physical dimensions, particularly the length and aperture (exit) dimensions, of antenna 300 ("Antenna 1"), a conventional horn antenna ("Conventional Horn", no metal lens inside), and an optimal horn antenna ("Optimal Horn", no metal lens inside) are compared. Figure 6 , it can be determined Figure 4A The curved wavefront of the reference horn antenna in is caused by the physical path length difference (δ). δ generally increases with the increase of the expansion angle θ0 (the angle defined by the two lateral end plates of the lens). In order to optimize or maximize the directivity of the E-plane sector horn antenna, Figure 6 The dimensions of the optimal horn antenna should meet the following requirements:

[0134]

[0135] Where L ap and L are the aperture (exit) length and focal length, respectively, and λ is the wavelength of the electromagnetic wave.

[0136] According to equation (2), for the same aperture (outlet) length L ap =5.3λ (at 15 GHz), the focal length L of the optimal horn antenna should be equal to 14.0λ. Therefore, the size of antenna 300 is reduced by more than 60% compared to the optimal horn antenna, and since the length L of the antenna is greatly shortened, the divergence angle θ0 is almost doubled. This shows that the design of antenna 300 using lens 306 can reduce the path difference and thus reduce the phase error.

[0137] Figure 7 Shows Figure 6 The simulated gains of the three antennas shown in (at θ = 0 0 Reference Figure 7 , for the same aperture (exit) size, antenna 300 ("antenna 1") has the best performance among the three antennas. The antenna gain achieved by antenna 300 ("antenna 1") is about 4 dB higher than that of the conventional horn antenna and about 1 dB higher than that of the optimal horn antenna. Therefore, the open horn antenna 300 can reduce the antenna size and increase the antenna gain.

[0138] To better illustrate the gain enhancement, FIG. 8A to FIG. 8D Shows Figure 6The best horn antenna in Figure 6 The horn antenna 300 in FIG. 1 and their respective simulated (normalized) electric field distributions at the aperture (exit) at 15 GHz. Figure 8C and Fig.8D As shown, for the same physical aperture (exit) size, horn antenna 300 ("antenna 1") has a larger effective radiating area than the optimal horn antenna.

[0139] 9A to 9C A prototype antenna 900 (having a flange, a power divider assembly, and a lens) manufactured according to the design of the antenna 300 with the lens 100 is shown. In this example, the prototype antenna 900 is manufactured by additive manufacturing using high temperature polylactic acid (PLA) with a dielectric constant of 2.66. Fig. 9A The skeleton shown. After the skeleton is formed, a metal material is applied thereto (e.g., electroplating using a metal material such as copper or aluminum) to obtain a skeleton with a metal coating that forms the antenna. In this example, the skeleton is processed (e.g., cut) to remove unnecessary parts. In this embodiment, after electroplating, four plastic strips (not coated with metal) are used to fix or support the lens and power divider components of the antenna 900. It should be noted that Fig. 9B and Fig. 9C A waveguide connected to a flange of antenna 900 is shown.

[0140] Experiments (simulation and measurement) were conducted on the fabricated antenna 900 to verify its performance. In the experiment, a Keysight E8361A network analyzer was used to measure the reflection coefficient of the prototype antenna 900, and a Satimo StarLab system was used to measure the antenna gain and radiation pattern of the prototype antenna 900.

[0141] Fig. 10A The measured and simulated reflection coefficients (|S 11 |). Fig. 10A As shown, the measured and simulated reflection coefficient |S 11 | Both have a 10dB bandwidth of 46% (in the range of 11.5GHz to 18.5GHz). Fig. 10B The measured and simulated gain of the prototype antenna 900 is shown (at θ = 0 0 ). The measured 1dB gain bandwidth is 25% (in the range of 13.9GHz to 18.0GHz) and the simulated 1dB gain bandwidth is 26.3% (in the range of 14.2GHz to 18.5GHz), where Fig. 10A and Fig. 10B Over the frequency range (in the range of 11.5 GHz to 18.0 GHz), the measured gain varies between 15.8 dBi and 18.3 dBi. Fig. 10A and Fig. 10B Reasonable agreement between measured and simulated results is shown.

[0142] Theoretically, the aperture efficiency ε ap It can be calculated based on the antenna gain G and the physical aperture area A p The calculations show that:

[0143]

[0144] Where λ is the wavelength of the electromagnetic wave. By substituting the measured realized gain into equation (3), the aperture efficiency ε of the prototype antenna 900 is found ap It is 109.3%.

[0145] Fig.11A and Fig. 11B The measured and simulated radiation patterns of the prototype antenna 900 in the E-plane and the H-plane are shown, respectively. Fig.11A and Fig. 11B It shows reasonable agreement between the measured and simulated results. It is understood that the differences between the measured and simulated results are mainly caused by tolerances and errors related to the manufacturing process, such as overflow of metal coating during electroplating, deformation of polylactic acid during additive manufacturing (3D printing), etc. Fig.11A and Fig. 11B As shown, a quasi-pencil beam is obtained, which is different from the fan-shaped beam of the conventional E-plane horn antenna. In addition, it can be seen that the sidelobe level (SLL) remains relatively high in both the E-plane and the H-plane. In this example, the relatively strong sidelobe level in the E-plane is due to the uniform amplitude distribution at the radiating aperture, while the relatively strong sidelobe level in the H-plane is caused by the open horn structure.

[0146] Fig.12 A horn antenna 1200 of one embodiment of the present invention is shown. The horn antenna 1200 of this embodiment has a similar design to the antennas 300, 900, but it can suppress the sidelobe level better than the antennas 300, 900. The horn antenna 1200 is operable to provide a conical amplitude distribution at its radiating aperture.

[0147] like Fig.12As shown, the horn antenna 1200 includes a flange 1202 connected to a waveguide 1210, a power divider assembly 1204 connected to the flange 1202, and a metal lens 1206 (same design as the lens 100) connected to the power divider assembly 1204. In this embodiment, four bolts 1212A and corresponding nuts 1212B are used to connect the flange 1202 to the waveguide 1210. The flange 1202 is designed to stabilize the antenna 1200. The waveguide is a standard waveguide WG18 (15.799×7.899mm 2 ). Antenna 1200 also includes a retaining strip 1208 for holding or supporting the power divider assembly 1204 and the lens 1206 in place. In this embodiment, the retaining strip 1208 is manufactured using polylactic acid additives. As described herein, antenna 1200 is also referred to as "antenna 2". In this embodiment, flange 1202, power divider assembly 1204, and metal lens 1206 are manufactured using aluminum alloy powder additives. In this embodiment, the power divider assembly 1204 can be referred to as the amplitude portion (because it mainly controls or manipulates the amplitude of the electromagnetic wave), and the lens 1206 can be referred to as the phase portion (because it mainly controls or manipulates the phase of the electromagnetic wave). With such an arrangement, in this embodiment, the amplitude and phase distribution of the electromagnetic wave can be substantially independently changed by adjusting the design of different parts of antenna 1200. This helps in the design of antenna 1200.

[0148] FIG. 13A to FIG. 13C The design of the horn antenna 1200 is shown in more detail. Fig.13A A flange 1202 and a power divider assembly 1204 are shown. The flange 1202 and the power divider assembly 1204 are generally similar to Figure 3A The flange 302 and power divider assembly 304 of the embodiment of the present invention. In this embodiment, the flange 1202 includes an opening (such as Fig.121206), so that the electromagnetic waves received from the waveguide 1210 can be provided to the power divider component 1204. In this embodiment, the power divider divider component 1204 includes a central channel portion, two channel portions branching from the central channel portion and arranged symmetrically with respect to the symmetry axis (for example, colinear or parallel to the symmetry axis of the lens 1206), and six power dividers 1204P1, 1204P2, 1204P3, 1204P4, 1204P5, 1204P6, which are arranged at the outlet of each of the two branch channel portions. More specifically, the power dividers 1204P1, 1204P2 are arranged at the outlet of each of the two branch channel portions to provide four channel portions, and the power dividers 1204P3, 1204P4, 1204P5, 1204P6 are further arranged at the outlet of each of the four branch channel portions to provide eight channel portions with different power ratios connected to the lens 1206. As shown Fig. 13B As shown, the front end or edge of each of the power dividers 1204P1, 1204P2 has a corresponding offset s1 away from the axis of symmetry and relative to the center line of a corresponding one of its upstream channel parts. The front end or edge of each of the power dividers 1204P3, 1204P4 has a corresponding offset s2 away from the axis of symmetry and relative to the center line of a corresponding one of its upstream channel parts. The front end or edge of each of the power dividers 1204P5, 1204P6 has a corresponding offset s3 away from the axis of symmetry and relative to the center line of a corresponding one of its upstream channel parts. Fig. 13C A lens 1206 with a nonlinear channel is shown, which is substantially the same as lenses 100, 306 and is therefore not described again. In this embodiment, the power divider assembly 1204 can provide an electromagnetic wave with a conical electric field distribution at the input (face A) of the lens 1206.

[0149] Fig.14 1 shows a perspective view and a side view of the antenna 1200 and a height distribution of the antenna 1200 (only the upper half is shown, the lower half is the same as the upper half). Fig.14 As shown, along the z direction (the general extension direction or long axis of antenna 1200), the opening formed in flange 1202 has a height h1, the power divider assembly 1204 has a varying height, and the lens 1206 has a substantially constant height h2 (25 mm). The varying height of the power divider assembly 1204 is arranged to reduce the sidelobe level of antenna 1200. As shown in FIG. Fig.14As shown, the power divider assembly 1204 includes a first portion having a varying height (from 0 to h1), a second portion having substantially the same height h1, and a third portion transitioning from height h1 to height h2, wherein the first portion is closer to the flange 1202 than the second portion, and the second portion is closer to the flange 1202 than the third portion.

[0150] Table III shows parameter values ​​of the antenna 1200 of this embodiment.

[0151] Table III - Parameters of Antenna 1200

[0152] Flange θ L <![CDATA[l1]]> <![CDATA[l2]]> <![CDATA[l3]]> 40.0mm 60° 108.0mm 3.0mm 12.0mm 3.0mm d <![CDATA[d0]]> <![CDATA[d 01 ]]> <![CDATA[w0]]> <![CDATA[w1]]> <![CDATA[w2]]> 19.4mm 2.0mm 3.0mm 1.0mm 106.0mm 59.7mm s <![CDATA[s1]]> <![CDATA[s2]]> <![CDATA[s3]]> <![CDATA[h1]]> <![CDATA[h2]]> 7.9mm 2.0mm 2.2mm 1.0mm 15.8mm 25.0mm

[0153] As described above, the design of antenna 1200 is substantially the same as the design of antennas 300 and 900, and antenna 1200 differs from antenna 900 in that antenna 1200 is modified to suppress the H-plane sidelobe level. Specifically, in antenna 1200, the height of lens 1206 is greater than the height of power divider assembly 1204, and power divider assembly 1204 includes a substantially smooth height transition to lens 1206. This arrangement can help restore impedance matching affected by the varying height distribution of power divider assembly 1204. In addition, in antenna 1200, the design of power divider assembly 1204 is modified as described above to suppress the E-plane sidelobe level.

[0154] To study the effect of varying height distribution in antenna 1200, a parametric study was performed.

[0155] Fig.15 1 shows the difference in height distribution between antenna 1200 and antenna 900. Fig.15 As shown, antenna 1200 ("antenna 2") has a smoother height profile and a larger aperture (exit of the lens) size h2. Fig.15 Also shown are the H-plane radiation patterns of antenna 1200 at 15 GHz for different values ​​of h2.

[0156] Fig.16 Measured normalized H-plane radiation patterns of antenna 1200 and antenna 900 are shown. Fig.16 As shown, when from h1=0.79λ (15.8mm at 15GHz, "antenna 1") to h2=1.25λ (25mm at 15GHz, "antenna 2").

[0157] The effect of power divider assembly 1204 in antenna 1200 (compared to the power divider assembly in antenna 900) on the xy-plane electric field distribution is considered.

[0158] Fig.17A The simulated electric field distribution of antenna 900 ("antenna 1") at 15 GHz is shown. Fig. 17B The simulated electric field distribution of antenna 1200 ("antenna 2") at 15 GHz is shown. As can be seen from these figures, the amplitude distribution of antenna 900 is more uniform than that of antenna 1200.

[0159] The radiation pattern is determined by the aperture field, ie, the electromagnetic wave field at the output aperture of the lens. Fig.18 The simulated electric field distribution at the output aperture of antenna 900 ("antenna 1") in the zy plane at 15 GHz and the simulated electric field distribution at the output aperture of antenna 1200 ("antenna 2") in the zy plane at 15 GHz are shown. Fig.18 As shown, the electric field amplitude of antenna 900 is generally more uniform than that of antenna 1200 because antenna 1200 has an expected conical electric field distribution.

[0160] Fig.19 Measured normalized E-plane radiation patterns of antenna 900 ("Antenna 1") and antenna 1200 ("Antenna 2") at 15 GHz are shown. Fig.19 As shown, the use of a tapered amplitude distribution in antenna 1200 can effectively reduce the sidelobe level compared to antenna 900.

[0161] In addition to suppressing the sidelobe level, antenna 1200 can also improve antenna gain, stability, and bandwidth by optimizing metal lens 1206.

[0162] Fig. 20 The simulated realized gain (at θ=0) of antenna 900 ("antenna 1") and antenna 1200 ("antenna 2") are shown. 0 ). refer to Fig. 20 , antenna 1200 has smaller gain fluctuations, having a 1 dB gain bandwidth of 30.0% (compared to 25.7% for antenna 900).

[0163] Fig.21A and Fig.21B A prototype horn antenna 2100 (with a waveguide, flange, power divider assembly, and lens) manufactured according to the design of horn antenna 1200 is shown. In order to reduce or avoid manufacturing problems associated with the manufacture of prototype antenna 900 (e.g., overflow and polylactic acid deformation), prototype antenna 2100 is directly additively manufactured using conductive materials (without using a polymer skeleton). The flange, power divider assembly, and lens of antenna 2100 are additively manufactured separately. Four plastic strips additively manufactured using a resin with a dielectric constant of 2.66 are used to fix or support the lens and power divider assembly of antenna 1200.

[0164] Experiments (simulation and measurement) were performed on the fabricated antenna 2100 to verify its performance. In the experiments, a Keysight E8361A network analyzer was used to measure the reflection coefficient of the prototype antenna 2100 and a Satimo StarLab system was used to measure the achieved antenna gain and radiation pattern of the prototype antenna 2100.

[0165] Fig. 22 The measured and simulated reflection coefficients (|S 11 |). Fig. 22 As shown, the measured and simulated -10 dB impedance bandwidths are both 46% (in the range of 11.5 GHz to 18.5 GHz).

[0166] Fig.23 The measured and simulated gains of antenna 2100 and reference antenna are shown (at θ = 0 0 ). In the measurements, a frequency range of 11.5 GHz to 18.0 GHz was considered, as the Satimo system can only operate up to 18 GHz. Fig.23 A reasonable agreement between the measured and simulated gain of antenna 2100 is shown. Fig.23 In , the reference antenna is a conventional horn antenna having the same aperture size, focal length, and antenna length as antenna 2100, and its performance is simulated for comparison. Fig.23 As shown, the simulated achieved gain of antenna 2100 is more than 3 dB higher than the reference horn antenna. At 18 GHz, the gain difference is as high as 6.3 dB. Antenna 2100 has a measured peak achieved gain of 19.1 dBi at 15 GHz and an aperture efficiency of 97.71% (calculated using the measured gain of antenna 900). Although this aperture efficiency is less than that of antenna 900 (109.3%), it is better than some existing designs. The gain fluctuation measured across the entire impedance passband (in the range of 11.5 GHz to 18.0 GHz) is less than 3 dB, with a measured 1 dB gain bandwidth of 30% (in the range of 13.3 GHz to 18.0 GHz).

[0167] FIG. 24A to FIG. 26B Measured and simulated normalized radiation patterns of antenna 2100 are shown. Specifically, Fig.24A and Fig. 24B The measured and simulated (normalized) radiation patterns of antenna 2100 in the E-plane (xy-plane) and H-plane (xz-plane) at 12 GHz are shown, respectively. Fig.25A and Fig.25B The measured and simulated (normalized) radiation patterns of antenna 2100 in the E-plane (xy-plane) and H-plane (xz-plane) at 15 GHz are shown, respectively. Fig.26Aand Fig.26B The measured and simulated (normalized) radiation patterns of antenna 2100 in the E-plane (xy-plane) and H-plane (xz-plane) at 18 GHz are shown, respectively.

[0168] like FIG. 24A to FIG. 26B As shown, a generally stable radiation pattern can be observed in the entire frequency band. By using a conical electric field amplitude distribution, the sidelobe level is less than -15dB.

[0169] Table IV shows the simulated and measured achieved gain and half-power beamwidth (HPBW) of antenna 2100. As shown in Table IV, the measured half-power beamwidth decreases slightly with increasing frequency. This is not surprising, as Fig.23 As shown, the antenna gain increases slightly with increasing frequency.

[0170] Table IV - Measured and simulated achieved gain and half power beamwidth (HPBW) over the impedance passband of antenna 2100

[0171]

[0172] Table V shows the performance of the above-described horn antenna embodiments, including antennas 300 , 900 and antennas 1200 , 2100 .

[0173] Table V - Performance of the Antenna Embodiments Shown

[0174]

[0175] Note: Antenna size, achieved gain and aperture efficiency are calculated at the center frequency of the reference operating band.

[0176] The present invention generally provides a lens for a horn antenna and a horn antenna including the lens. In some embodiments, a compact broadband horn antenna is provided, which has a metal lens that can be used as an H-plane metal lens. The antenna can provide a substantially uniform electric field distribution at the radiating aperture, provide high achieved gain, high aperture efficiency and / or have a compact size. The use of a metal lens can generally handle higher powers than a dielectric lens or a metasurface. In some embodiments, a compact broadband horn antenna with a lower sidelobe level is provided (for example, by introducing a conical electric field distribution at the input of the metal lens of the antenna). In some embodiments, the antenna includes a spatial power divider and an H.

[0177] Planar metal lenses, all of which can be metal and at least partially additively manufactured. In some embodiments, the nonlinear channels of the lens have different lengths to convert the original quasi-cylindrical wavefront into a quasi-planar wavefront over a wide frequency range, thereby providing a broadband high-gain antenna. Some embodiments of the present invention provide a horn antenna with a metal lens. In some examples, the amplitude and phase distribution of the electromagnetic wave are controlled by different parts of the antenna, respectively.

[0178] Some embodiments of the present invention have provided a gain enhancement method for a horn antenna. The horn antenna includes a broadband lens made at least in part of metal. The metal lens may include multiple channels with substantially the same path length. The shape, form, size, etc. of the channel may be designed to obtain a desired phase and / or amplitude distribution at the radiation aperture of the lens or antenna. The lens can increase the aperture efficiency and / or achieved gain of the horn antenna. In some embodiments, the expansion angle and focal length of the lens may be different from those shown. In some embodiments, the channels of the lens may have different wavy shapes, such as wavy shapes based on sine functions, parabolic functions, square functions, triangular functions, sawtooth functions, etc. In some embodiments, the total number of channels in the lens may be different from that shown. In some embodiments, the plates and / or channels do not necessarily need to be arranged symmetrically around an axis.

[0179] In some embodiments, a horn antenna having a substantially uniform electric field distribution at a radiation aperture is provided. The horn antenna may include a metal lens and a proportional power divider. In some embodiments, a horn antenna having a conical electric field distribution at a radiation aperture is provided. The horn antenna may include a metal lens having a substantially horn-shaped plate assembly (including a nonlinear channel) and a power divider of different ratios. In some embodiments, the antenna and / or gain enhancement lens may be made of any type of metal material and may be manufactured by additive manufacturing or computer numerical control machining techniques. In some embodiments, the antenna may be fed by an SMA interface or a waveguide. In some embodiments, the power divider and the metal lens are integrated with the horn antenna. In some embodiments, the operating frequency of the antenna may be different from that shown above. In some embodiments, the present invention may be applied to array design.

[0180] In one example application, the antenna of the present invention can be used for point-to-point wireless communication (e.g., in a point-to-point wireless system) to provide long-range signal coverage. Since the antenna can have a compact structure and high gain in some embodiments, it can be used in applications such as wireless relay communication and satellite communication in some examples. In some examples, the lens and / or antenna can be suitable for Ku-band applications.

[0181] Those skilled in the art will appreciate that many changes and / or modifications may be made to the invention as shown in a particular embodiment to provide other embodiments of the invention. Therefore, the embodiments of the invention described should be considered illustrative rather than restrictive in all respects. The above Summary of the Invention section sets forth exemplary optional features of some aspects of the invention. Some embodiments of the invention may include one or more of these optional features (some of which are not specifically shown in the drawings). Some embodiments of the invention may lack one or more of these optional features (some of which are not specifically shown in the drawings). One or more features in one embodiment and one or more features in another embodiment may be combined to provide other embodiments of the invention. In some embodiments, the shape, form, size and / or geometry of the lens (e.g., channel and / or plate) may be different from those specifically disclosed above. The plate assembly is generally horn-shaped, which means that the degree of expansion does not need to be strictly (continuously) increased. The number of channels and / or plates of the lens may be different from those specifically disclosed above. In some embodiments, one or more of the shape, form, size, etc. of the horn antenna or lens may be different from those specifically disclosed above.

Claims

1. A lens for a horn antenna, comprising: a generally flared plate assembly extending generally along an axis from a first side to a second side opposite the first side, the generally flared plate assembly defining a plurality of non-linear channels operable to manipulate electromagnetic waves received at the first side and provide manipulated electromagnetic waves at the second side; Each of the plurality of non-linear channels comprises a first opening located at the first side and a second opening located at the second side; The plurality of first openings of the plurality of non-linear channels are spaced apart from one another; The plurality of second openings of the plurality of non-linear channels are spaced apart from one another; as well as The plurality of non-linear channels have different linear lengths but have substantially the same physical length.

2. The lens according to claim 1, wherein: The plurality of nonlinear channels are arranged such that when the electromagnetic wave received at the first side comprises a quasi-planar wavefront, the manipulated electromagnetic wave obtained at the second side comprises a quasi-planar wavefront.

3. The lens according to claim 1, wherein: The plurality of non-linear channels are generally symmetrically arranged with respect to the axis. 4 . The lens according to claim 3 , wherein a width of the first opening perpendicular to the axis is smaller than a width of the second opening perpendicular to the axis.

5. The lens according to claim 4, wherein: The plurality of non-linear channels include: a first plurality of non-linear channels disposed on one side of the axis; and A second plurality of non-linear channels are disposed on another side of the axis.

6. The lens according to claim 5, wherein: For each nonlinear channel in the first plurality of nonlinear channels, a center of the first opening and a center of the second opening are connected by a straight line, the straight line extending at a non-zero angle to the axis, Wherein, the straight lines of the first plurality of nonlinear channels are arranged at different angles relative to the axis, so that the angle formed by the straight lines associated with the nonlinear channels closer to the axis and the axis is smaller than the angle formed by the straight lines associated with the nonlinear channels farther from the axis and the axis.

7. The lens according to claim 6, wherein: The generally flared plate assembly includes a plurality of plates defining the plurality of non-linear channels, the plurality of plates comprising: a first plate extending at a non-zero angle to said axis, a second plate extending at a non-zero angle to the axis, and a plurality of intermediate plates disposed between the first plate and the second plate; wherein the first plate and the second plate jointly define a first width perpendicular to the axis at the first side and a second width perpendicular to the axis at the second side; and wherein the first width is smaller than the second width.

8. The lens according to claim 7, wherein: Each of the plurality of intermediate plates comprises: a first end, which is arranged on said first side, a second end, which is arranged on the second side, a first surface extending between the first end and the second end, and A second surface is opposite to the first surface and extends between a first end and a second end.

9. The lens according to claim 8, wherein: the first surface of each of the plurality of intermediate plates comprising a wavy surface; and Wherein, the second surface of each of the plurality of intermediate plates comprises a wavy surface.

10. The lens according to claim 9, wherein: For at least some of the plurality of intermediate plates, the wavy surface of the same intermediate plate has substantially the same wavy shape.

11. The lens according to claim 10, wherein: For at least some of the plurality of intermediate plates, the wavy surfaces of different intermediate plates have different wavy shapes.

12. The lens according to claim 11, wherein: The wavy surface is represented by a cosine-based function f n (x) = a n cos(ω n x) is defined, where n is the identifier of the intermediate board, a n is the amplitude, ω n is the angular frequency.

13. The lens according to claim 8, wherein: The first ends of the plurality of intermediate plates are generally arranged on a same first plane, and the first plane is arranged to be generally perpendicular to the axis. wherein the second ends of the plurality of intermediate plates are substantially arranged on the same second plane, the second plane being arranged substantially perpendicular to the axis, and Wherein, the first plane and the second plane are substantially parallel.

14. The lens according to claim 8, wherein each of the plurality of intermediate plates further comprises: a third end extending between the first end and the second end, and A fourth end is opposite to the third end and extends between the first end and the second end.

15. The lens according to claim 14, wherein: The third ends of the plurality of intermediate plates are generally arranged on the same third plane, the third plane being parallel to the axis, wherein the fourth ends of the plurality of intermediate plates are substantially arranged on the same fourth plane, the fourth plane being parallel to the axis, and Wherein, the same third plane and the same fourth plane are substantially parallel.

16. The lens according to claim 14, wherein: For each of the plurality of intermediate plates, a distance between the third end and the fourth end respectively defines a height of the intermediate plate, and Wherein, the heights of the plurality of intermediate plates are substantially the same.

17. The lens according to claim 9, wherein: the first surface of each of the plurality of intermediate plates being a metal surface; and Wherein, the second surface of each of the plurality of intermediate plates is a metal surface.

18. The lens of claim 7, wherein the plurality of plates are made entirely of metal.

19. The lens of claim 7, further comprising a support for holding the plurality of plates in place.

20. The lens according to claim 1, wherein: The generally flared plate assembly defines an envelope that is generally in the shape of a trapezoidal prism having an upper base on the first side and a lower base on the second side.

21. A horn antenna, comprising: The lens according to claim 1; as well as A power splitter assembly is operably connected to the lens.

22. The horn antenna according to claim 21, further comprising: waveguide; as well as A flange is connected between the waveguide and the power divider assembly.

23. The horn antenna according to claim 21, wherein: The power divider assembly includes one or more power dividers arranged to manipulate electromagnetic waves from a feed source and provide the manipulated electromagnetic waves to the lens.

24. The horn antenna according to claim 21, wherein: said power divider assembly and said lens extending generally along said axis of said generally flared plate assembly, wherein the lens defines a first height perpendicular to the axis, wherein the power divider assembly defines a second height perpendicular to the axis, and Wherein, the first height and the second height are substantially the same.

25. The horn antenna according to claim 21, wherein: said power divider assembly and said lens extending generally along said axis of said generally flared plate assembly, wherein the lens has a first height perpendicular to the axis, and Among them, the power distributor components include: a first portion having a second height less than the first height and perpendicular to the axis, and A second portion transitions from said first portion to a lens.

26. The horn antenna according to claim 25, wherein: The second portion is a generally flared portion that develops along the axis and is generally perpendicular to the development of the generally flared plate assembly along the axis.

27. A lens for a horn antenna, comprising: a generally flared plate assembly extending generally along an axis from a first side to a second side opposite the first side, the generally flared plate assembly defining a plurality of non-linear channels operable to manipulate electromagnetic waves received at the first side and provide manipulated electromagnetic waves at the second side; Each of the plurality of nonlinear channels comprises: a first opening located on the first side; a second opening located at the second side; a third opening located at a third side, the third side being proximate to the first side and the second side; a fourth opening located at a fourth side, the fourth side being close to the first side and the second side and opposite to the third side; Each of the first opening, the second opening, the third opening and the fourth opening of each nonlinear channel of the plurality of nonlinear channels is separated from a corresponding one of the first opening, the second opening, the third opening and the fourth opening of an adjacent nonlinear channel of the plurality of nonlinear channels.

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