Phased array antenna device

Abstract

A phase array antenna device (1) includes multiple antenna elements (2), each antenna element (2) being located within a corresponding unit cell (3) of the phase array antenna device (1), and the unit cells (3) being arranged adjacent to each other in a non-overlapping manner. A feed circuit (5) transmits antenna signals between a common control unit (4) and the corresponding antenna elements (2), the feed circuit (5) including multiple antenna element transmission line segments (10), each segment extending to the antenna element (2); and having multiple phase shift devices (11), for each antenna element (2), a corresponding phase shift device (11) is arranged along the corresponding antenna element signal transmission line (10) extending to the antenna element (2). The phase array antenna device (1) includes several feed transmission line segments (7), each feed transmission line segment (7) including more than two transition structures (9) distributed along the feed transmission line segment (7), each transition structure (9) providing signal coupling to the corresponding antenna element transmission line segment (10). The transition structure (9) of the antenna element transmission line segment (10) extending to the unit cell (3) is located in the direction through which the feed transmission line segment (7) passes or crosses the unit cell (3), and is located at a position greater than the phase shift distance of the unit cell (3) extending in that direction.

Description

Technical Field

[0001] This invention relates to a phase array antenna device having a plurality of antenna elements arranged in a spatial distribution designed to allow the phase array antenna device to transmit and receive superimposed radio frequency signals in different directions, wherein each antenna element is located within a corresponding unit cell of the phase array antenna device, and the unit cells are arranged adjacent to each other in a non-overlapping manner; a feed circuit for transmitting antenna signals between a common control unit and the respective antenna elements, wherein the feed circuit includes a plurality of antenna element transmission line segments, each transmission line segment extending into the antenna element; and a plurality of phase shifting devices, wherein for each antenna element, a corresponding phase shifting device is arranged along the corresponding antenna element signal transmission line extending into the antenna element. Prior Technology

[0002] Phased array antenna devices operated using radio frequency (RF) signals allow the transmission of RF electromagnetic beams that can be electronically manipulated to point in different directions without moving the antenna device. Similarly, many phased array antenna devices also allow for amplification of the receiving sensitivity of RF waves from a particular direction without moving the antenna device.

[0003] In most phased array antenna devices, radio frequency (RF) current from the transmitter is fed to individual antenna elements in the correct phase relationship, causing the RF waves from the individual antenna elements to superimpose and combine to increase the radiation intensity in the desired direction and cancel out the radiation intensity in the undesired direction. In a phased array antenna device, power from the transmitter is fed to numerous antenna elements via devices called phase shifters, which electronically change the corresponding phase of the antenna signals, thereby manipulating the superimposed RF beams in different directions. Typically, a phased array antenna device must consist of many small antenna elements, sometimes including more than a thousand antenna elements arranged in a predetermined spatial distribution. For many phased array antenna devices, a large number of antenna elements are arranged in a matrix spatial distribution in a plane. Even though the distance between adjacent antenna elements can be preset to almost any value, space-saving arrangements require this distance to be approximately λ / 2, where λ is the wavelength of the RF signal to be transmitted or received by the phased array antenna device.

[0004] For many phased array antenna devices, each antenna element is arranged within a unit cell, which defines a small region in a plane dedicated to the corresponding antenna element arranged within that plane. This plane can be divided into multiple unit cells, each containing one antenna element and typically including similar patterns of other electrodes or elements. These unit cells cover the plane in a non-overlapping but adjacent manner, and are typically arranged in a matrix. Generally, the unit cell has no structural limitations but can be considered as the region surrounding an antenna element with repeating patterns of electrodes and other elements. The extension of a unit cell in a given direction is equal to the distance between adjacent antenna elements in that direction. For each unit cell, the corresponding antenna element is connected to the control unit via a segmented antenna element transmission line. With a large number of unit cells containing antenna elements, the space requirement for the corresponding number of antenna element transmission line segments becomes enormous, significantly limiting the available space for the antenna elements.

[0005] To reduce the total length of antenna element transmission line segments required for individual connection to each antenna element, many phased array antenna devices include a common feed network that begins with a small number of first common feed transmission line segments, each of which branches into two separate second common feed transmission line segments. This branching can be repeated several times, resulting in a common feed network with cascaded common feed transmission line segments, until, after N branching stages, the final total number of common feed transmission line segments equals the required number of antenna element transmission line segments extending to the corresponding antenna element.

[0006] However, to allow for cost-effective fabrication of such cascaded common feed circuits, all common feed transmission line segments are arranged on the same surface of the substrate layer. Any crossings or vertical changes away from the surface by the common feed transmission line segments should be avoided. Therefore, such cascaded common feed circuits impose several limitations on the design of the phase array antenna device and the arrangement of the unit cells and corresponding antenna elements. Furthermore, if crossings or overlaps of the common feed transmission line segments are avoided, the total length of the resulting common feed transmission line segments and antenna element transmission line segments used for signal transmission between the control unit and antenna elements will be considerably large.

[0007] For many phased array antenna devices, part or all of the length of the antenna element transmission line segment is designed to serve as a phase shifting element. For each antenna element, there exists a given phase shift of the radio frequency signal, which is required to obtain the peak intensity of the superimposed radio frequency signal of all antenna elements in a predetermined direction. Therefore, the antenna element transmission line segment is typically arranged within the corresponding unit cell of the antenna element, and for that antenna element, a predetermined phase shift is achieved by the corresponding antenna element transmission line segment extending into the antenna element and connecting the antenna element to a common control unit.

[0008] It is possible to use transmission line segments as phase-shifting devices by arranging tunable dielectric material between the electrodes of a transmission line element. However, the range of different dielectric constant values ​​of the tunable dielectric material that can be controlled and modified by applying an electric field is limited, and therefore the maximum phase shift that can be preset for signal transmission along such transmission line segments is also limited. Therefore, for many applications, the minimum length required for a transmission line segment used as a phase-shifting device exceeds the maximum extension of the unit cell.

[0009] Because the minimum length of the transmission line segment used as a phase shifter is longer than the extension of the unit cell, the transmission line segment of the antenna element typically has a spiral or tortuous path with several bends and corners. However, each curve of the transmission line segment of the antenna element, and especially each corner, can cause unwanted electromagnetic radiation, resulting in a loss of signal quality and increased interference between adjacent unit cells.

[0010] Therefore, an efficient and space-saving signal transmission connection arrangement is needed between the control unit and each antenna element, thereby reducing unwanted electromagnetic radiation segmented along the antenna element transmission lines. Summary of the Invention

[0011] The present invention relates to the phase array antenna device described above, wherein the phase array antenna device includes a plurality of feed transmission line segments, wherein each feed transmission line segment includes more than two transition structures distributed along the feed transmission line segment, wherein each transition structure provides signal coupling to the corresponding antenna element transmission line segment, thereby connecting a plurality of dedicated antenna element transmission line segments to the same feed transmission line segments, and wherein the transition structures of the antenna element transmission line segments extending into the unit cell are positioned in the direction of the feed transmission line segment, which passes through or through the unit cell with a phase shift distance greater than the extension of the unit cell measured in that direction.

[0012] In contrast to a common-feed transmission line segment that branches into two secondary common-feed segments, a feed transmission line segment does not branch into two secondary transmission line segments. Instead, it comprises more than two transition structures, each of which allows signal coupling between the feed transmission line segment and the antenna element transmission line segment. Therefore, a single feed transmission line segment is connected to and feeds several, and potentially a large number, antenna element transmission line segments. This significantly reduces the space required to connect each unit cell with the corresponding antenna element to the common feed point of the feed network or the control unit of the phase array antenna assembly.

[0013] The transition structure is located at a certain phase shift distance from the unit cell to which the feed transmission line segment is connected via the transition structure. This allows for a smaller bend in the corresponding antenna element transmission line segment. The phase shift distance between the transition structure within the unit cell and the connection to the antenna element is preferably equal to or slightly greater than the minimum length of the antenna element transmission line segment required for its capability and performance as a phase shifting device. Therefore, the antenna element transmission line segment does not need to have a sharply bent or tortuous path, which reduces unwanted electromagnetic radiation emissions.

[0014] According to a preferred embodiment of the invention, the phase shift distance is between one and two extensions of the unit cell. For many applications with radio frequency signals, a distance greater than two diameters of the unit cell or the longest extension is often sufficient for the antenna element transmission line segment to act as a phase shifting device. Current tunable dielectric materials, such as tunable liquid crystal materials, provide a range of dielectric constant values ​​that allow for the generation and control of phase shifts of approximately 360 degrees or greater for radio frequency signals propagating along the antenna element transmission line segment. The shorter the antenna element transmission line segment, the less space is required in the path of the antenna element transmission line at distances from other electrodes or conductive elements arranged in the same plane or on the same substrate layer surface of the antenna element transmission line. The fewer bends and corners within the path of the antenna element transmission line segment, the less electromagnetic radiation emitted that could degrade signal quality or interfere with other transmission lines or signal processing elements within the phase array antenna device.

[0015] According to an advantageous aspect of the invention, the subsequent transition structure is designed such that the antenna element transmission line segments of the continuous transition structure are arranged on opposite sides of the feed transmission line segments. Therefore, the antenna element transmission line originating from the first transition structure along the feed transmission line segment can extend substantially parallel to the feed transmission line segment and through the second transition structure without requiring lateral offset to allow another antenna element transmission line segment originating from the second transition structure and also extending along the same side of the feed transmission line segment. Alternating arrangement of continuous antenna element transmission lines on both sides of the feed transmission line segment helps reduce the path length along the antenna element transmission line segment. Furthermore, the alternating start and end points of the paths of the antenna element transmission line segments relative to the feed transmission line segment allow for a more compact and space-saving arrangement of the antenna elements and corresponding unit cells.

[0016] According to a highly advantageous aspect of the invention, all antenna element transmission line segments originating on a first side of the feed transmission line segment extend in a first direction parallel to the direction of the feed transmission line segment, while all antenna element transmission line segments originating on a second side of the feed transmission line segment opposite to the first side extend in a second direction opposite to the first direction. This topology is considered an additional and important advantage, namely, by alternating the starting points and directions of the continuously starting antenna element transmission line segments, it is readily possible to alternately connect adjacent antenna elements via antenna element transmission line segments extending in the first direction and coupled to the feed transmission line segment from the first side, and via antenna element transmission line segments extending in the second direction and coupled to the feed transmission line segment from the second side. Therefore, without additional restrictions or requirements on the antenna element transmission line segments, adjacent antenna elements can be connected from opposite sides of the antenna elements to their respective antenna element transmission line segments, which can be used for alternating polarization of adjacent antenna elements. Alternating polarization of antenna elements results in a 180° polarization shift in the radiation transmitted or received by adjacent antenna elements, which provides a significant reduction in undesirable polarization, thereby leading to improved signal quality. In short, such a topology allows for the simple implementation of sequential rotation in phase array antenna designs.

[0017] In another advantageous aspect of the invention, all antenna element transmission line segments have the same length. If the antenna element transmission line segments are used as part of a phase shifting device, having the same length allows for a single and identical design for all phase shifting devices. This facilitates the manufacture and operation of the phase shifting devices because, for example, applying the same bias voltage to several phase shifting devices will result in the same phase shift being produced by those devices.

[0018] To further reduce unwanted electromagnetic radiation along the antenna element transmission line segments, all segments of the antenna element transmission line extend parallel to or at an angle of less than 50° relative to the feed transmission line segments, with the corresponding antenna element transmission lines coupled to these feed transmission line segments via transition structures. According to this aspect of the invention, the antenna element transmission line segments do not include any bends or curves with a change in direction greater than 50°, and preferably only include bends with a change in direction of 45° or less along the route.

[0019] According to another advantageous aspect of the invention, the unit cells are arranged in a matrix configuration, and each feed transmission line segment extends along a straight line that passes through or through multiple unit cells arranged along a straight line within the matrix configuration. The feed transmission line segments, which do not contain any curves, also reduce any unwanted electromagnetic radiation originating from radio frequency signals transmitted along the feed transmission line segments. Furthermore, the fabrication of feed transmission line segments extending along straight lines is less prone to defects or unavoidable inaccuracies that degrade the signal quality and performance of the phase array antenna device during manufacturing.

[0020] According to an advantageous embodiment of the invention, each feed transmission line segment extends along or through more than two unit cells and includes a transition structure for each of the more than two unit cells. Therefore, the distance between the feed transmission line segment providing signal transmission connectivity to the control unit and each corresponding antenna element is relatively short, which also reduces the space requirement of the antenna element transmission line segments, each connecting the feed transmission line segment to the corresponding antenna element.

[0021] According to another aspect of the invention, each feed transmission line segment extends along a straight line. Typically, the antenna elements, and therefore the unit cells, are spatially arranged in a matrix configuration. For such a matrix arrangement, the path of the feed transmission line segment can be a straight line extending between two adjacent rows of unit cells, or a straight line passing through many unit cells within the matrix-arranged unit cells. The straight-line extension of the feed transmission line segments also reduces unwanted electromagnetic radiation emissions caused by bends or corners within the transmission line path.

[0022] According to an advantageous embodiment of the invention, the feed transmission line segment is implemented as a microstrip transmission line with a linear microstrip electrode arranged at a distance from a ground electrode. The microstrip line and transition structure used to couple the signal into the antenna element transmission line segment are easy to manufacture. Furthermore, the ground electrode required for the microstrip transmission line may be useful in providing a back shield that prevents electromagnetic radiation emissions away from the intended direction and towards the rear side of the unit cell arrangement.

[0023] In yet another, and also advantageous, embodiment of the invention, the feed transmission line segment is implemented as a differential pair transmission line, wherein two similar differential pair electrodes extend along the feed transmission line segment. Differential pair transmission lines do not require a ground electrode, which allows for more design options for the phased array antenna device. Furthermore, signal transmission along the differential pair transmission line is less affected by interfering electromagnetic radiation emissions that occur within the phased array antenna device and cannot be completely avoided. Moreover, designing the antenna element transmission line segment as a differential pair transmission line is also considered advantageous. Then, the transition structure required for signal coupling between the feed transmission line segment and the antenna element transmission line segment does not require changing the type of transmission line from a microstrip transmission line to a differential pair transmission line.

[0024] A highly advantageous aspect of the invention is that each antenna element transmission line segment can be implemented as a differential pair transmission line, wherein two similar differential pair electrodes extend along the antenna element transmission line segment, thereby electrically isolating at least one of the two differential pair electrodes of the antenna element transmission line segment from the corresponding feed transmission line segment. Since at least one of the two differential pair electrodes of the antenna element transmission line segment is not electrically connected to the feed transmission line segment, it is possible to apply a potential difference to the two differential pair electrodes of the antenna element transmission line, independent of any potential or potential difference in the feed transmission line segment. Therefore, it is possible to utilize phase shifting devices with tunable dielectric material arranged between or near the two differential pair electrodes of the antenna element transmission line, and to apply an individual bias voltage to each phase shifting device. This allows for a very simple design and operation of the antenna elements and phase shifting devices within each unit cell.

[0025] According to an aspect of the invention, the transition structure includes two linear transition electrodes, and further includes an overlapping section, wherein a portion of at least one of the two linear transition electrodes extends parallel to each other, but at a distance from the feed transmission line segment, it is used for signal coupling from the feed transmission line segment to the antenna element transmission line segment, whereby each of the two linear transition electrodes extends to a corresponding one of the two differential pair electrodes of the antenna element transmission line segment. Therefore, the two linear transition electrodes can be designed and manufactured as corresponding end segments of the corresponding differential pair electrodes of the antenna element transmission line segment of the differential pair transmission line. The length of the overlapping portion, particularly the length of the parallel-extending linear transition electrodes at a distance from the feed transmission line segment, can be adapted to provide strong and effective coupling, but as short as possible to reduce the space required for the transition structure. Because at least one of the two linear transition electrodes is not electrically connected to the feed transmission line segment, there is no need for, for example, vias or interconnect electrode structures providing electrical connections between different surfaces of the substrate layer, which allows for simple and cost-effective manufacturing and a space-saving design of the transition structure.

[0026] To provide a very cost-effective and space-saving design for the transition structure, one of the two linear transition electrodes is designed as a balun-to-unbalance converter type linear transition electrode, which provides a 180° phase difference relative to the other linear transition electrode. The balun-to-unbalance converter type linear transition electrode includes a U-shaped delay section, which provides a simple means of providing a 180° phase difference for signal transmission segmented along the antenna element transmission line.

[0027] The feed transmission line segments with several, and possibly a large number, transition structures allow signal coupling between the feed transmission line segments and the corresponding large number of antenna element transmission line segments. This results in a phased array antenna topology with a very small footprint, which is required for the unit cell containing the corresponding antenna elements, while providing very high performance and efficiency, as well as a favorable signal-to-noise ratio, compared to conventional phased array antenna devices known in the prior art. Furthermore, by avoiding the strong bends or twists in the antenna element transmission line segments, unwanted electromagnetic radiation during signal propagation along these segments can be significantly reduced without imposing strict limitations on the topology and design of the phased array antenna device. Simple Explanation of the Diagram

[0028] The invention will be more fully understood and further features will become apparent upon reference to the following detailed description and accompanying drawings. The drawings are merely representative and are not intended to limit the scope of the claims. In fact, those skilled in the art will appreciate upon reading the following specification and viewing the current drawings that various modifications and variations can be made without departing from the innovative concept of the invention. Similar portions depicted in the drawings are referred to by the same reference numerals.

[0029] [Figure 1] illustrates a schematic representation of a phased array antenna device having multiple unit cells arranged in a matrix pattern, and each unit cell including an antenna element, whereby each antenna element is connected to a control unit via a feed network for transmitting radio frequency signals between the control unit and the antenna element. [Figure 2] illustrates a schematic top view of a column of unit cells, whereby the feed transmission line segments extending along the column of unit cells include transition structures for each unit cell, and antenna element transmission line segments for signal transmission between the transition structures and corresponding antenna elements. [Figure 3] illustrates a schematic top view of two columns of unit cells, whereby the feed transmission line segments extending along these unit cell columns include transition structures with antenna element transmission line segments arranged on opposite sides of the feed transmission line segments. [Figure 4] illustrates a schematic top view of the matrix arrangement of unit cells, in which several feed transmission lines are segmented, each extending along a column of unit cells. [Figure 5] illustrates a schematic top view of two columns of unit cells similar to those in Figure 3, but with different arrangements and designs of antenna element transmission line segments. [Figure 6] illustrates a schematic top view of the matrix arrangement of the unit cells. [Figure 7] illustrates a schematic top view of another embodiment of the matrix arrangement of unit cells. [Figure 8] illustrates a schematic top view of a transition structure that provides signal coupling between microstrip transmission lines, and [Figure 9] illustrates a schematic top view of a transition structure that provides signal coupling between a microstrip transmission line and a differential pair transmission line. Implementation

[0030] Figure 1 shows a schematic illustration of a phased array antenna device 1 comprising multiple antenna elements 2, arranged in a matrix topology on a plane. All antenna elements 2 are schematically illustrated as squares. The antenna elements 2 can be any design or type of radiating element that transmits or receives radio frequency signals radiated by electromagnetic radiation. The plane can be divided into a corresponding number of unit cells 3, each unit cell 3 comprising one antenna element 2 and a region surrounding that antenna element 2. Adjacent unit cells 3 do not overlap but are adjacent to each other, forming a matrix arrangement adapted to the positions of the antenna elements 2. The extension of a unit cell 3 in a given direction is equal to the distance between adjacent antenna elements 2 in that direction. The shape of the unit cell 3 can be rectangular as shown in Figure 1. The unit cell 3 can also have any other shape, such as honeycomb or circular. The unit cell 3 generally has no structural limitations.

[0031] The phase array antenna device 1 also includes a control unit 4 for controlling the radio frequency signals received or transmitted by the antenna elements 2. Signal transmission between the control unit 4 and each antenna element 2 is provided by a feed network 5. The feed network 5 includes a common feed network. A common feed transmission line segment 6 of the common feed network originates from the control unit 4 and, after several branches, extends into a feed transmission line segment 7. Each feed transmission line segment 7 extends in a straight line along the columns 8 of the unit cells 3 within a matrix arrangement of the unit cells 3. Each feed transmission line segment 7 passes through several unit cells 3 and includes a corresponding number of transition structures 9. Each antenna element 2 is connected to a corresponding transition structure 9 via an antenna element transmission line segment 10, which is not shown in Figure 1 but is shown in Figures 2 to 4. Therefore, the radio frequency signal originating from the control unit 4 is transmitted along the common feed transmission line segment 6 and along the feed transmission line segment 7, and via the transition structure 9 along the continuous antenna element transmission line segments 10 to the corresponding antenna element 2. When the antenna element 2 is used to receive the radio frequency signal, the radio frequency signal propagates along the antenna element transmission line segment 10, enters the corresponding feed transmission line segment 7 through the transition structure 9, and is directed toward the control unit 4 via the common feed transmission line segment 6.

[0032] Antenna element transmission line segment 10 is also designed to influence the phase of the radio frequency signal and is therefore used as a phase shifting device 11. However, the minimum length of antenna element transmission line segment 10 required to perform a phase shift sufficient for usefully superimposing the radio frequency signals of all antenna elements 2 exceeds the extension of the unit cell 3. Conventional phase array antenna devices 1 include antenna element transmission line segments 10 with helical or tortuous routes, which are arranged within the corresponding unit cell 3. However, each bend or corner along the route of antenna element transmission line segment 10 causes undesirable electromagnetic radiation emissions, which affect signal quality and interfere with signal transmission along other antenna element transmission line segments or feed transmission line segments 7.

[0033] To avoid bends and turns along the route of antenna element transmission line segment 10, antenna element transmission line segment 10 connects antenna element 2 of a given unit cell 3 to a transition structure 9 located at a phase shift distance d in another unit cell 3, the phase shift distance d exceeding the extension of unit cell 3 in any direction. Preferably, the phase shift distance d is large enough to allow a substantially straight route for antenna element transmission line segment 10, as schematically illustrated in Figures 2 to 4. The route of antenna element transmission line segment 10 is significantly different from a helical or zigzag route and is primarily a straight route with only a small lateral offset necessary for bridging the lateral distance between antenna element 2 and transition structure 9 at feed transmission line segment 7. The design and route of antenna element transmission line segment 10 can be adapted to cause minimal possible electromagnetic radiation emissions during signal transmission of radio frequency signals along antenna element transmission line segment 10.

[0034] Furthermore, due to the straight path of the feed transmission line segment 7, the space requirement for the transmission line connecting each antenna element 2 to the control unit 4 is significantly less than that of a conventional common feed network. In addition, the straight path of the feed transmission line segment 7 also reduces unwanted electromagnetic radiation emissions during signal transmission along the feed transmission line segment 7.

[0035] The schematic design shown in Figure 2 includes a feed transmission line segment 7 extending along a column of 8-cell units 3. The feed transmission line segment 7 includes a transition structure 9 and an antenna element transmission line segment 10, each starting from the same side of the feed transmission line segment 7 and each extending to the antenna element 2 in the next cell 3 within the same column of 8-cell units 3.

[0036] The schematic design illustrated in Figure 3 includes a feed transmission line segment 7, which is connected to the antenna element 2 on its opposite side. For each successive transition structure 9 arranged along the path of the feed transmission line segment 7, the corresponding antenna element transmission line segment 10 starts on the opposite side of the feed transmission line segment 7 and extends substantially parallel to the feed transmission line segment 7 until the next unit cell 3 and the antenna element 2 located within that unit cell 3. Due to the alternating positions and paths of the antenna element transmission line segments 10, the paths of the corresponding antenna element transmission line segments 10 can be even less curved than the corresponding paths of the antenna element transmission line segments 10 shown in Figure 2.

[0037] Figure 4 schematically illustrates an exemplary design of a matrix arrangement of unit cells 3 having several columns 8, whereby adjacent columns 8 are offset relative to each other in the direction of the respective column 8. Each feed transmission line segment 7 is connected to several antenna element transmission line segments 10, which are arranged alternately on opposite sides of the feed transmission line segment 7.

[0038] Preferably, the antenna element transmission line segment 10 is designed and manufactured as a differential pair transmission line with two differential pair electrodes that extend substantially parallel to each other and are spaced apart. The feed transmission line segment 7 can be designed and manufactured as a microstrip transmission line with a linear microstrip electrode that extends at a distance from the planar ground electrode. However, it is also possible to design and manufacture the feed transmission line segment 7 as a differential pair transmission line, or the antenna element transmission line segment 10 as a microstrip transmission line.

[0039] Figure 5 schematically illustrates an exemplary design of a feed transmission line segment 7 connected to the antenna element 2 on opposite sides of the feed transmission line segment 7. This aspect of the topology is similar to the embodiment shown in Figure 3. However, the direction of the antenna element transmission line segment 10 starting from the first side of the feed transmission line segment 7 is different from the direction of the antenna element transmission line segment 10 starting from the second side of the feed transmission line segment 7 opposite to the first side. Therefore, for example, as shown in Figure 5, the direction of the antenna element transmission line segment 10 starting from the left side of the feed transmission line segment 7 is upward, while the direction of the antenna element transmission line segment 10 starting from the right side of the feed transmission line segment 7 is downward, as shown in Figure 5.

[0040] Figure 6 schematically illustrates another exemplary embodiment of the matrix arrangement and connection of antenna elements 2 in corresponding unit 3. Adjacent columns of the matrix arrangement of antenna elements 2 are not offset relative to each other. Therefore, antenna elements 2 are located along a straight line in columns 8 and rows 8.

[0041] Similar to the embodiment illustrated in Figure 5, the direction of the antenna element transmission line segment 10 starting from the first side of the feed transmission line segment 7 is opposite to the direction of the antenna element transmission line segment 10 starting from the second side opposite to the first side of the feed transmission line segment 7. Unlike the embodiment of Figure 5, all antenna element transmission line segments 10 have equal lengths. Such a topology is considered very advantageous because it allows for the sequential rotation of the antenna elements 2, i.e., relative radial polarization of adjacent antenna elements 2. Furthermore, due to the identical lengths of the antenna element transmission line segments 10, the design and control of the phase shifting device 11 along the antenna element transmission line segments 10 can also be identical.

[0042] Figure 7 illustrates another embodiment of a matrix arrangement with antenna elements 2. Adjacent columns of antenna elements 2 and their corresponding unit cells 3 are offset relative to each other. The arrangement of antenna element transmission line segments 10 on opposite sides of the feed transmission line segments 7 and the relative orientation of consecutive antenna element transmission line segments 10 are similar to the embodiment shown in Figure 6. Furthermore, Figure 7 shows bias voltage lines 19 extending toward each antenna element transmission line segment 10. Each bias voltage line 19 allows an individual bias voltage to be applied to the electrode of the corresponding antenna element transmission line segment 10, thereby controlling the phase shift of the radio frequency signal transmitted along the antenna element transmission line segment 10, applied by the corresponding phase shift device 11.

[0043] Figure 8 schematically illustrates an exemplary embodiment of the transition structure 9, which can be used to couple radio frequency signals between two microstrip transmission lines. The linear microstrip electrode 12 of the feed transmission line segment 7 extends along a straight line. The end segment 13 of the linear microstrip electrode 14 of the antenna element transmission line segment 10 forms a linear transition electrode and extends parallel to the linear microstrip electrode 14 of the feed transmission line segment 7, but at a certain distance from the linear microstrip electrode 14. Thus, the length of the parallel end segment 13 of the linear microstrip electrode 14 is adapted and preset to provide strong signal coupling of the radio frequency signal between the linear microstrip electrode 12 of the feed transmission line segment 7 and the linear microstrip electrode 14 of the antenna element transmission line segment 10.

[0044] Figure 9 schematically illustrates another exemplary embodiment of the transition structure 9, which allows coupling of radio frequency signals between a microstrip transmission line and a differential pair transmission line. The end segment 15 of the first linear differential pair electrode 16 forms a linear transition electrode and extends parallel to the linear microstrip electrode 12 of the feed transmission line segment 7, but at a distance from the linear microstrip electrode 12 of the feed transmission line segment 7 (and preferably at another substrate). For clarity, the first linear differential pair electrode 16 is illustrated using dashed lines. After the end segment 15, the first linear differential pair electrode 16 extends along a U-shaped delay path 17, resulting in a 180° phase shift relative to the signal coupled to the second linear differential pair electrode 18. The U-shaped delay path 17 can also be considered as part of the linear transition electrode of the transition structure 9. The second linear differential pair electrode 18 can be connected to or coupled to the linear microstrip electrode 12 of the feed transmission line segment 7 with or without electrical connection. Figure 8 illustrates the electrical connection, which is designed as a branch from the linear microstrip electrode 12 of the feed transmission line segment 7 to the branch linear differential pair electrode 18 of the antenna element transmission line segment 10.

[0045] 1: Antenna device 2: Antenna components 3: Unit cell 4: Control Unit 5: Feeder network circuit 6: Segmentation of common power supply transmission line 7: Segmentation of power supply transmission line 8: column 9: Transition Structure 10: Antenna element transmission line segmentation 11: Phase Shifting Device 12: Electrode 13: End section 14: Electrode 15: End section, electrodes 16: Electrode 17: U-shaped delay route 18: Electrode 19: Bias Voltage Line d: Phase shift distance

Claims

1. A phase array antenna device (1) having a plurality of antenna elements (2) arranged in a spatial distribution, the spatial distribution being designed to allow the phase array antenna device (1) to transmit and receive superimposed radio frequency signals in different directions, wherein each antenna element (2) is positioned within a corresponding unit cell (3) of the phase array antenna device (1), and wherein the unit cells (3) are arranged adjacent to each other in a non-overlapping manner; having a feed circuit (5) for transmitting antenna signals between a common control unit (4) and the respective antenna elements (2), wherein the feed circuit (5) includes a plurality of antenna element transmission line segments (10), each segment extending into the antenna element (2); and having a plurality of phase shifting devices (11), wherein for each antenna element (2), a phase shifting device is used to transmit antenna signals along the line extending into the antenna element (2). The corresponding antenna element signal transmission line (10) is arranged with a corresponding phase shift device (11), characterized in that the phase array antenna device (1) includes a plurality of feed transmission line segments (7), wherein each feed transmission line segment (7) includes more than two transition structures (9) distributed along the feed transmission line segment (7), wherein each transition structure (9) provides signal coupling to the corresponding antenna element transmission line segment (10), thereby connecting a plurality of dedicated antenna element transmission line segments (10) to the same feed transmission line segment (7), and wherein the transition structure (9) extending to the antenna element transmission line segment (10) in the unit cell (3) is positioned in the direction through which the feed transmission line segment (7) passes or crosses the unit cell (3), and is positioned at a phase shift distance greater than the extension of the unit cell (3) measured in that direction.

2. The phase array antenna device (1) according to claim 1, wherein, The phase shift distance is between one and two extensions of the unit cell (3).

3. The phase array antenna device (1) according to claim 1 or 2, wherein, The subsequent transition structure (9) is designed in such a way that the antenna element transmission line segment (10) of the continuous transition structure (9) along the feed transmission line segment (7) is arranged on the opposite side of the feed transmission line segment (7).

4. The phase array antenna device (1) according to claim 3, wherein, All antenna element transmission line segments (10) originating from the first side of the feed transmission line segment (7) extend in a first direction parallel to the feed transmission line segment (7), while all antenna element transmission line segments (10) originating from the second side of the feed transmission line segment (7) opposite to the first side extend in a second direction opposite to the first direction.

5. The phase array antenna device (1) according to claim 1 or 2, wherein, All antenna element transmission line segments have the same length.

6. The phase array antenna device (1) according to claim 1 or 2, wherein, All segments of the antenna element transmission line segment (10) extend parallel to the feed transmission line segment (7) or at an angle of less than 50° relative to the feed transmission line segment (7), and the corresponding antenna element transmission line segment (10) is coupled to the feed transmission line segment (7) via the transition structure (9).

7. The phase array antenna device (1) according to claim 1 or 2, wherein, The unit cells (3) are arranged in a matrix configuration, and each of the feed transmission line segments (7) extends along a straight line that passes through or through the multiple unit cells (3) arranged along the straight line.

8. The phase array antenna device (1) according to claim 1 or 2, wherein, The feed transmission line segment (7) is implemented as a microstrip transmission line with a linear microstrip electrode (12), which is arranged at a certain distance from the planar ground electrode.

9. The phase array antenna device (1) according to claim 1 or 2, wherein, The feed transmission line segment (7) is implemented as a differential pair transmission line, wherein two similar linear differential pair electrodes extend along the feed transmission line segment (7).

10. The phase array antenna device (1) according to claim 1 or 2, wherein, Each of the antenna element transmission line segments (10) is implemented as a differential pair transmission line, wherein two similar differential pair electrodes (16, 18) extend along the antenna element transmission line segment (10), thereby electrically isolating at least one of the two differential pair electrodes (16) of the antenna element transmission line segment (10) from the corresponding feed transmission line segment (7).

11. The phase array antenna device (1) according to claim 10, wherein, The transition structure (9) includes two linear transition electrodes (12, 15), and the transition structure (9) also includes an overlapping section, wherein a portion of at least one (15) of the two linear transition electrodes is parallel to the feed transmission line segment (7) but extends at a distance from the feed transmission line segment (7) for coupling a signal from the feed transmission line segment (7) to the antenna element transmission line segment (10), wherein each of the two linear transition electrodes (12, 15) extends to a corresponding one of the two differential pair electrodes (18, 16) of the antenna element transmission line segment (10).

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