Signal transmission device including plurality of rotman lenses

Abstract

A signal transmission device comprises: an antenna unit having a plurality of patch antennas; a first signal line electrically connected to each of the plurality of patch antennas to operate in a first polarization; and a second signal line electrically connected to each of the plurality of patch antennas to operate in a second polarization. A signal transmission length of the second signal line may be formed to be longer than a signal transmission length of the first signal line by a quarter of a wavelength (λg).

Description

A signal transmission device comprising multiple Rotman lenses

[0001] The present disclosure relates to a signal transmission device that radiates multi-polarized signals. A specific embodiment relates to a signal transmission device including Rotman lenses.

[0002] Phased array antennas can adjust beam steering direction by electronically controlling the phase of radio waves on a per-element basis. This element-by-element phase control is typically implemented using phase shifters at the radio frequency (RF) level. These phase shifters increase the weight, size, and cost of the phased array antenna.

[0003] Furthermore, phased array antennas require polarization conversion, such as vertical, horizontal, or circular polarization. In this regard, the Rotman lens is a passive beam-forming network based on the principles of optical lenses. Signals passing through the Rotman lens are designed to have identical amplitude and phase, and can be used as phase control elements to synthesize beams by transmitting them to the array antenna.

[0004] Depending on the selection of the beam port, which is the signal input port of the Rotman lens, the wave front transmitted to the array port, which is the signal output port, can be changed. Since the phase of the array antenna can be controlled as the wave front is changed, beam steering characteristics can be provided to the antenna without a separate phase controller.

[0005] However, when designing a Rotman lens, the radiation performance (directivity, beam width, polarization, etc.) of the array antenna is pre-selected, and the lens shape is determined accordingly. In this regard, a precise definition of the antenna radiation characteristics is required, and in particular, the signal transmitted to the signal output of the Rotman lens has a sequential phase gradient. Therefore, there is a problem in that beam synthesis with two or more polarization characteristics is difficult.

[0006] The purpose of this specification is to provide a signal transmission device that radiates multi-polarized signals.

[0007] The purpose of this specification is to provide a signal transmission device that radiates multi-polarized signals in a frequency band of millimeter waves or higher.

[0008] The purpose of this specification is to provide a signal transmission device that radiates a multi-polarization signal capable of combining beams having two or more polarization characteristics.

[0009] The purpose of this specification is to provide beam forming in one direction in a signal transmission device that radiates a multi-polarization signal capable of beam synthesis having two or more polarization characteristics.

[0010] The purpose of this specification is to form multi-beams in a signal transmission device that radiates multi-polarization signals capable of beam synthesis with two or more polarization characteristics.

[0011] In order to achieve the above or other purposes, a signal transmission device including a plurality of Rotman lenses according to an embodiment includes an antenna unit having a plurality of patch antennas; a first signal line electrically connected to each of the plurality of patch antennas to operate with a first polarization; and a second signal line electrically connected to each of the plurality of patch antennas to operate with a second polarization. A signal transmission length of the second signal line may be formed to be longer by 1 / 4 of a wavelength (λg) than a signal transmission length of the first signal line.

[0012] According to an embodiment, the first signal line may be composed of a first input line connected to the modem unit, a first output line connected to the antenna unit, and a first Rotman lens disposed between the first input line and the first output line. The second signal line may be composed of a second input line connected to the modem unit, a second output line connected to the antenna unit, and a second Rotman lens disposed between the second input line and the second output line.

[0013] According to an embodiment, one side and the other side of the first Rotman lens may be connected to the first input line and the first output line. One side and the other side of the second Rotman lens may be connected to the second output line and the second input line. The second Rotman lens may be formed in a symmetrical structure with respect to the first Rotman lens with respect to the vertical axis of the substrate.

[0014] According to an embodiment, the first input line may include a first port to a fifth port connected to one side of the first Rotman lens. The second input line may include a sixth port to a tenth port connected to the other side of the second Rotman lens. The modem unit may control the signal of the first polarization to be beamformed by changing the port through which the signal is input to any one of the first port to the fifth port, and may control the signal of the second polarization to be beamformed by changing the port through which the signal is input to any one of the sixth port to the tenth port.

[0015] According to an embodiment, the modem unit can control the ports into which the signal is input so that any one pair is selected from among the first to fifth pairs of the first port, the sixth port, the fifth port, and the tenth port. By changing any one of the selected pairs of ports, the signal of circular polarization can be controlled to be beamformed.

[0016] In an embodiment, the plurality of patch antennas may include first to eighth patch antennas. The first output line may include first to eighth ports configured to apply signals of a first polarization to the first to eighth patch antennas. The second output line may include ninth to sixteenth ports configured to apply signals of a second polarization to the first to eighth patch antennas.

[0017] According to an embodiment, the plurality of patch antennas may include first to eighth patch antennas arranged in a two-dimensional structure. Each of the first to eighth patch antennas may include a plurality of patch antenna elements arranged to be spaced apart in the first axial direction.

[0018] The technical effects of a signal transmission device including a plurality of Rotman lenses according to the present specification are described as follows.

[0019] According to an embodiment, a beam pattern of vertical / horizontal / circular polarization can be formed through a signal transmission device that radiates a multi-polarization signal.

[0020] According to an embodiment, a vertical / horizontal / circular polarization tunable beam-switching solution can be proposed by implementing a Rotman lens-based signal generation circuit network capable of imparting two or more polarization characteristics to an array antenna.

[0021] According to an embodiment, a signal transmission device that radiates a vertical / horizontal / circularly polarized variable multi-polarized signal in a frequency band of millimeter waves or higher can be implemented.

[0022] According to an embodiment, a multi-signal generation circuit network based on a multi-Rotman lens capable of applying vertical or horizontal polarization signals can be used to share array antennas so that signals can be supplied to the array antennas independently / mutually. Accordingly, signals can be selectively applied according to the polarization characteristics to be radiated, thereby implementing vertical / horizontal / circular polarization.

[0023] According to the embodiment, selective beam steering for vertical / horizontal / circular polarization is possible, and radiation performance control such as beam-steering / beam-forming / beam-broadening is possible.

[0024] According to an embodiment, by improving the antenna radiation performance of a multi-beam generation mode using multiple Rotman lenses, it is possible to improve multi-beam operation characteristics that are difficult to implement with a beamformer such as a single Rotman lens or a Butler matrix.

[0025] According to an embodiment, in a signal transmission device that emits a multi-polarization signal capable of beam synthesis having two or more polarization characteristics, beam forming can be provided in a uniaxial direction by changing the ports of input lines connected to a Rotman lens.

[0026] According to an embodiment, in a signal transmission device that emits a multi-polarization signal capable of synthesizing beams having two or more polarization characteristics, while forming multi-beams, signals are applied to ports in different areas to reduce mutual interference between the multi-beams.

[0027] Further scope of the applicability of this specification will become apparent from the detailed description below. However, since various changes and modifications within the spirit and scope of this specification will be apparent to those skilled in the art, it should be understood that the detailed description and specific examples, such as preferred embodiments, are given by way of example only.

[0028] FIG. 1 illustrates the structure of an array antenna module including a plurality of elements according to the present specification.

[0029] Figure 2 shows a structure implemented with a reflective RIS and a transparent RIS according to the present specification.

[0030] FIGS. 3a and 3b illustrate beams formed in an optical signal path-based array antenna according to the present disclosure.

[0031] FIG. 4 illustrates a signal transmission device including a plurality of Rotman lenses according to the present specification.

[0032] FIG. 5 is an enlarged view of the first Rotman lens and the first output line of the signal transmission device of FIG. 4.

[0033] FIG. 6 is a drawing comparing the first output lines and the second output lines of the signal transmission device of FIG. 4.

[0034] FIG. 7 is an enlarged view of adjacent patch antennas, ports of the first input line, and dummy ports of the antenna section of FIG. 4.

[0035] Figure 8 shows output lines of a signal transmission device formed in a straight or curved structure.

[0036] Figure 9 shows the phase values ​​for each frequency according to the slope angle of the curve in the output lines of Figure 8.

[0037] Fig. 10 shows beam patterns of the antenna section of the signal transmission device of Fig. 4.

[0038] FIG. 11 illustrates a signal transmission device including a plurality of Rotman lenses and a two-dimensional array antenna structure according to the present specification.

[0039] Fig. 12 is an enlarged view of a portion of the two-dimensional array antenna of Fig. 11.

[0040] FIG. 13 and FIG. 14 show beam patterns and axis ratios when a signal is applied to the third or eighth port of the first or second input lines of the signal transmission device of FIG. 11.

[0041] FIG. 15 shows beam patterns when signals are simultaneously applied to the third and eighth ports of the first and second input lines of the signal transmission device of FIG. 11.

[0042] Figure 16 shows the gain, beam steering angle, and beam patterns according to signal application to each port of the first input line of Figure 11.

[0043] Figure 17 shows the gain, beam steering angle, and beam patterns according to signal application to each port of the second input line of Figure 11.

[0044] Figure 18 shows the gain, beam steering angle, and beam patterns according to signal application to each port of the first and second input lines of Figure 11.

[0045] Figure 19 shows a multi-beam pattern when a signal is applied to one port of the first input line and one port of the second input line.

[0046] Figure 20 shows beam patterns when M ports are selected for one of the first and second input lines and N ports for the remaining ones.

[0047] Hereinafter, an antenna module having a phase delay is described in relation to a signal transmission device that radiates a multi-polarized signal according to the present specification.

[0048] In this regard, an antenna module including a plurality of elements according to the present specification may be referred to as a phase delay array antenna module. The antenna module may be configured to include a plurality of radiators and a phase delay element capable of implementing phase delay. The phase delay element may be implemented as a feed structure of a specific structure without separate electronic components such as a phase shifter.

[0049] The array antenna module can be configured to support 6G wireless communication services. In this regard, the array antenna module can be configured to operate in the millimeter wave band or the 10 GHz band. The array antenna module can be applied to mobile communication antennas, vehicle antennas, or satellite communication antennas.

[0050] 6G wireless communication services aren't limited to electronic devices like mobile terminals or video display devices. They can also be applied to fully autonomous vehicles, artificial intelligence (AI) robots, and electronic devices supporting the augmented and virtual reality (AR / VR)-based metaverse.

[0051] FIG. 1 illustrates the structure of an array antenna module, which is a module including a plurality of elements according to the present specification. Referring to FIG. 1, the array antenna module (1000) may be configured as an array antenna (1100) including a plurality of elements (1100-1 to 1100-8). The number of the plurality of elements is not limited to eight and may vary depending on the application.

[0052] The antenna module (1000) may be configured as a one-dimensional array antenna in which a plurality of elements are arranged in one axial direction. As another example, the antenna module (1000) may be configured as a two-dimensional array antenna in which a plurality of elements are arranged in one axial direction and another axial direction perpendicular thereto.

[0053] The spacing (G1) between the plurality of elements (1100-1 to 1100-8) can be implemented as a numerical value related to a wavelength corresponding to an operating frequency. Each of the plurality of elements (1100-1 to 1100-8) can be operably coupled to a phase delay element (1150-1 to 1150-8). The phase delay elements (1150-1 to 1150-8) can be formed as a feed structure having a phase delay. The phase delay elements (1150-1 to 1150-8) can be formed as a feed structure connecting adjacent antenna elements.

[0054] A transmission line (1200) connected to a plurality of elements (1100-1 to 1100-8) may be implemented as a waveguide, a microstrip line, a strip line, or a substrate integrated waveguide (SIW). Each of the plurality of elements (1100-1 to 1100-8) may be independently controlled to be turned on / off. Each of the plurality of elements (1100-1 to 1100-8) may be independently controlled to be turned on / off to adjust the beam forming direction of the antenna module (1000).

[0055] As the plurality of elements (1100-1 to 1100-8) are independently turned on / off, the phase of the signal applied to the plurality of elements (1100-1 to 1100-8) can be varied as illustrated in the transmission line (1200) of FIG. 1. As the interval between the on / off operations among the plurality of elements (1100-1 to 1100-8) decreases, the phase difference between adjacent elements increases. Accordingly, as the interval between the on / off operations among the plurality of elements (1100-1 to 1100-8) decreases, the beamforming angle increases.

[0056] Meanwhile, an antenna module comprising a plurality of antenna elements according to the present specification may be capable of phase adjustment when combined with a reconfigurable intelligent surface (RIS). In this regard, FIG. 2 illustrates a structure implemented with a reflective RIS and a transmissive RIS according to the present specification.

[0057] Referring to FIG. 2(a), the antenna module (1000) may be configured to include a reflective RIS (1000a) and at least one external antenna (1300). A wireless signal radiated from the external antenna (1300) may be configured to be reflected by the reflective RIS (1000a). The beamforming angle of the wireless signal may be varied by independently varying the on / off state of each element constituting the reflective RIS (1000a).

[0058] Referring to FIG. 2(b), the antenna module (1000) may be configured to include a transitive RIS (1000b) and at least one external antenna (1300). A wireless signal radiated from the external antenna (1300) may be configured to pass through the transitive RIS (1000b). The beamforming angle of the wireless signal may be varied by independently varying the on / off state of each element constituting the transitive RIS (1000b).

[0059] Hereinafter, a signal transmission device including a plurality of Rotman lenses according to the present specification will be described. Specifically, FIGS. 3A and 3B illustrate beams formed in an array antenna based on an optical signal path according to the present specification.

[0060] Referring to FIG. 3a, a signal can be transmitted through a body area of ​​the Rotman lens (1230) from the curved structure of the Rotman lens (1230) to one end (1220a) of the output line. When a signal is applied through the first focus (F1) of the Rotman lens (1230), an in-phase wavefront (WF1) is formed to be inclined by a specific angle (θ) in the Y-axis direction. Accordingly, the steering angle of the beam pattern (BP1) of the signal radiated through the antenna unit (1100) can be steered to a specific angle (θ).

[0061] Referring to FIG. 3b, a signal can be transmitted through a body region of the Rotman lens (1230) from the curved structure of the Rotman lens (1230) to one end (1220b) of the output line. When a signal is applied through a center point between the first focus (F1) and the second focus (F2) of the Rotman lens (1230), a wavefront (WF2) of the same phase is formed in the Y-axis direction. Accordingly, the steering angle of the beam pattern (BP2) of the signal radiated through the antenna unit (1100) can be steered to an angle of 0 degrees.

[0062] Referring to FIGS. 3a and 3b, a passive beam-forming network based on ray optics may be used, in which all propagation paths dispersed through lenses form an in-phase plane to synthesize beams. The phase-control element may be designed to supply a signal with a uniform amplitude and a specific phase to the antenna element by propagating a signal through a Rotman lens. Since the phase applied to the antenna element can be controlled by selecting a specific signal input section, it has the characteristic of being able to provide beam-steering characteristics to the antenna without a separate phase controller.

[0063] Beam ports may be formed as signal input sections at the front end of the Rotman lens (1230). The body area of ​​the Rotman lens (1230) forms a lens body as a signal distribution section. A signal output section is formed from one end (1220a, 1220b) of the output line to the antenna section (1100). One end (1220a, 1220b) of the output line may be defined as array ports.

[0064] Figures 4 to 7 illustrate a signal transmission device including a plurality of Rotman lenses according to the present specification. Figure 4 illustrates a signal transmission device including a plurality of Rotman lenses according to the present specification. Figure 5 is an enlarged view of the first Rotman lens and the first output line of the signal transmission device of Figure 4.

[0065] Referring to FIGS. 4 and 5, the signal transmission device (1000) may be configured to include a first input line (1210), a first output line (1220), and a first Rotman lens (1230). The first input line (1210) may include first to fifth ports (P1 to P5) connected to one side of the Rotman lens (1230). The first output line (1220) may include first to eighth ports (Po1 to Po8) connected to the other side of the Rotman lens (1230). The first to eighth ports (Po1 to Po8) of the first output line (1220) may be connected to respective antenna elements (PA1 to PA8) of the array antenna (1100).

[0066] Beam forming of an array antenna connected to the first to eighth ports (Po1 to Po8) of a first output line (1220) can be performed by applying a signal to one of the first port (P1) to the fifth port (P5) of the first input line (1210). When a signal is applied to the first port (P1), the beam of the array antenna can be steered by 2α. When a signal is applied to the second port (P2), the beam of the array antenna can be steered by α. When a signal is applied to the third port (P3), the beam of the array antenna can be steered by 0 degrees. When a signal is applied to the fourth port (P4), the beam of the array antenna can be steered by -α. When a signal is applied to the fifth port (P5), the beam of the array antenna can be steered by -2α. For example, when signals are applied in the order of the first port (P1) to the fifth port (P5), the beam of the array antenna can be steered by 25 degrees, 12.5 degrees, 0 degrees, -12.5 degrees, and 25 degrees.

[0067] A first input line (1210) including a first port (P1) to a fifth port (P5) forms beam ports for selecting a beam of an array antenna. A first Rotman lens (1230) disposed between the first input line (1210) and the first output line (1220) is connected to the first input line (1210) and the first output line (1220). The first Rotman lens (1230) may be implemented as a conductive plate on a substrate.

[0068] The signal transmission device (1000) may be configured to include a plurality of dummy ports that eliminate reflections between signals transmitted through the first Rotman lens (1230). The upper and lower regions of the first Rotman lens (1230) may be implemented as dummy ports.

[0069] The first output line (1220) including the first port (Po1) to the eighth port (Po8) of the first output line (1220) forms array ports. Signals having different phases between the first port (Po1) to the eighth port (Po8) of the first output line (1220) can be connected to each antenna element of the array antenna. The signals applied to the first port (Po1) to the eighth port (Po8) are A0ej φ0 A7ej inland φ7 It can be expressed as. The magnitudes of the signals applied to the first port (Po1) to the eighth port (Po8), A0 to A7, can be configured to have the same value. The phases φ0 to φ7 of the signals applied to the first port (Po1) to the eighth port (Po8) can be determined depending on which port among the first port (P1) to the fifth port (P5) of the first input line (1210) the signal is applied to.

[0070] When a signal is applied to the first port (P1), there is a phase difference of 2△φ between adjacent ports of the first output line (1220). When a signal is applied to the second port (P2), there is a phase difference of △φ between adjacent ports of the first output line (1220). When a signal is applied to the third port (P3), there is a phase difference of 0 degrees between adjacent ports of the first output line (1220) and the same phase value. When a signal is applied to the fourth port (P4), there is a phase difference of -△φ between adjacent ports of the first output line (1220). When a signal is applied to the fifth port (P5), there is a phase difference of -2△φ between adjacent ports of the first output line (1220).

[0071] The beam steering angle (θ) of the array antenna (1100) can be determined as in mathematical expression 1 according to the phase difference (△φ) between adjacent ports of the first output line (1220). The beam steering angle (θ) can be determined according to the wavelength (λ) corresponding to the operating frequency, the spacing (d) between adjacent antenna elements of the array antenna (1100), and the phase difference (△φ).

[0072]

[0073] The structure of FIG. 4, which includes first and second input lines (1210, 1310), first and second Rotman lenses (1230, 1330), first and second output lines (1230, 1330), and an antenna unit (1100), can be implemented with a length of 36.25 mm in the X-axis direction and a width of 28.75 mm in the Y-axis direction. The structure of FIG. 4 can operate at a center frequency of 160 GHz.

[0074] Meanwhile, the structure of FIG. 5 including the first input line (1210), the first Rotman lens (1230), and the first output line (1220) can be implemented with a length of 13.5 mm in the X-axis direction and a width of 14 mm in the Y-axis direction. The thickness of the substrate on which the first input line (1210), the first Rotman lens (1230), and the first output line (1220) are formed can be formed to be 0.05 mm. The structure of FIG. 5 including the first input line (1210), the first Rotman lens (1230), and the first output line (1220) can operate at a center frequency of 160 GHz. The structure of FIG. 5 can be set to have a focal angle, a beam steering angle, and a focal length of 25 degrees, 25 degrees, and 3.59 mm (1.91λ0).

[0075] Fig. 6 is a drawing comparing the first output lines and the second output lines of the signal transmission device of Fig. 4. Fig. 7 is an enlarged drawing of adjacent patch antennas, the port of the first input line, and the dummy ports of the antenna unit of Fig. 4.

[0076] Referring to FIGS. 4, 5, and 6(a), a first line (L1) among the first output lines (1220) is formed as a straight line. A second line (L2) among the first output lines (1220) is formed as a curved line having a first height between the bottom and the top in the Y-axis direction. A third line (L3) among the first output lines (1220) is formed as a curved line having a second height greater than the first height between the bottom and the top in the Y-axis direction. A fourth line (L4) among the first output lines (1220) is formed as a curved line having a third height greater than the second height between the bottom and the top in the Y-axis direction.

[0077] Referring to FIGS. 4, 5, and 6(b), a first line (L1) among the second output lines (1320) is formed as a straight line. A second line (L2) among the second output lines (1320) is formed as a curved line having a first height between the bottom and the top in the Y-axis direction. A third line (L3) among the second output lines (1320) is formed as a curved line having a second height greater than the first height between the bottom and the top in the Y-axis direction. A fourth line (L4) among the second output lines (1320) is formed as a curved line having a third height greater than the second height between the bottom and the top in the Y-axis direction.

[0078] Referring to FIGS. 4 to 6, the signal transmission length of the second output line (1320) may be formed to be a predetermined length longer than the signal transmission length of the first output line (1220), so that the antenna unit (1100) may be configured to implement multiple polarized waves. The signal transmission length of the second output line (1320) may be formed to be 1 / 4 of the wavelength (λg) longer than the signal transmission length of the first output line (1220).

[0079] Referring to FIGS. 4, 5, and 7(a), the distance between adjacent antenna elements (PA1, PA2) of the antenna unit (1100) may be spaced apart in the Y-axis direction by 0.5 times the wavelength (λg). The distance between adjacent antenna elements (PA1, PA2) is not limited to 0.5 times the wavelength (λg), and may be spaced apart by 0.5 to 0.8 times the wavelength (λg) depending on the application. By reducing the distance between adjacent antenna elements (PA1, PA2), the beam steering angle can be increased. Meanwhile, by increasing the distance between adjacent antenna elements (PA1, PA2), the antenna directivity can be improved. Other adjacent antenna elements of the antenna unit (1100) may also be spaced apart by the same distance.

[0080] Meanwhile, the antenna elements (PA1, PA2) and the first and second output lines (1220, 1320) of the antenna unit (1100) may be arranged on different substrates (layers) or may be arranged on the same substrate (layer). When the antenna elements (PA1, PA2) and the first and second output lines (1220, 1320) are arranged on different layers, the feed lines implemented as the first and second output lines (1220, 1320) may be implemented as a coupling feed structure or a via feed structure. When the antenna elements (PA1, PA2) and the first and second output lines (1220, 1320) are arranged on the same layer, the feed lines implemented as the first and second output lines (1220, 1320) may be implemented as a direct feed structure. Compared to a direct feed structure, when feed lines are implemented with a coupled feed structure, the bandwidth characteristics of the antenna can be improved.

[0081] Referring to FIGS. 4, 5, and 7(b), a first port (P1) of a first input line (1210) may be electrically connected to lines of a first Rotman lens (1230). A plurality of circular holes from which a metal pattern is removed may be formed along the inner side of the boundary lines of the first port (P1) of the first input line (1210). A plurality of circular holes from which a metal pattern is removed may also be formed along the inner side of the boundary lines of other ports (P2 to P5) of the first input line (1210). Meanwhile, a plurality of circular holes from which a metal pattern is removed may also be formed along the inner side of the boundary lines of ports (P6 to P10) of the second input line (1310).

[0082] Referring to FIGS. 4, 5, and 7(b), each of the dummy ports (DP31 to DP33) may be connected to lines of the second Rotman lens (1330). Each of the dummy ports (DP31 to DP33) may have a plurality of circular holes formed along the inner side of the boundary lines with the metal pattern removed. Each of the dummy ports (DP11 to DP13) may be connected to lines of the first Rotman lens (1230). Each of the dummy ports (DP31 to DP33) may have a plurality of circular holes formed along the inner side of the boundary lines with the metal pattern removed.

[0083] Referring to FIGS. 4 to 7, a signal transmission device (1000) including a plurality of Rotman lenses can be configured to include an antenna unit (1100), a first signal line (1200), and a second signal line (1300).

[0084] The antenna unit (1100) may include a plurality of patch antennas (PA1 to PA8). The antenna unit (1100) may be a one-dimensional array antenna composed of a plurality of patch antennas (PA1 to PA8) spaced apart from each other in the vertical axis direction. The antenna unit (1100) is not limited to a 1x8 array antenna, and may be configured to include any number of antenna elements.

[0085] A first signal line (1200) may be electrically connected to each of a plurality of patch antennas (PA1 to PA8) of an antenna unit (1100) to operate with a first polarization. The first signal line (1200) may be composed of a first input line (1210), a first output line (1220), and a first Rotman lens (1230). The first input line (1210) may be configured to be connected to a modem unit (1400). The first output line (1220) may be configured to be connected to the antenna unit (1100). The first Rotman lens (1230) may be arranged between the first input line (1210) and the first output line (1220).

[0086] The second signal line (1300) may be electrically connected to each of the plurality of patch antennas (PA1 to PA8) of the antenna unit (1100) to operate with a second polarization. The second signal line (1300) may be composed of a second input line (1310), a second output line (1320), and a second Rotman lens (1330). The second input line (1310) may be configured to be connected to the modem unit (1400). The second output line (1320) may be configured to be connected to the antenna unit (1100). The second Rotman lens (1330) may be arranged between the second input line (1310) and the second output line (1320).

[0087] The signal transmission length of the second signal line (1300) may be formed to be a predetermined length longer than the signal transmission length of the first signal line (1200), so that the antenna unit (1100) may be configured to implement multiple polarized waves. The signal transmission length of the second signal line (1300) may be formed to be longer by 1 / 4 of the wavelength (λg) than the signal transmission length of the first signal line (1200). The signal transmission length of the second output line (1320) may be formed to be longer by 1 / 4 of the wavelength (λg) than the signal transmission length of the first output line (1220).

[0088] It may be configured with a plurality of ports to support multiple polarizations of the first input line (1210) and the second input line (1220). The first input line (1210) may include a first port (P1) to a fifth port (P5) connected to one side of the first Rotman lens (1230). The second input line (1310) may include a sixth port (P6) to a tenth port (P10) connected to the other side of the second Rotman lens (1330).

[0089] The modem unit (1400) can control the signal of the first polarization to be beamformed in the vertical axis direction in which the plurality of patch antennas (PA1 to PA8) are arranged by changing the port through which the signal is input to any one of the first port (P1) to the fifth port (P5). The modem unit (1400) can control the signal of the second polarization to be beamformed in the vertical axis direction in which the plurality of patch antennas (PA1 to PA8) are arranged by changing the port through which the signal is input to any one of the sixth port (P6) to the tenth port (P10). In this regard, the first polarization may be set to a vertical polarization, and the second polarization may be set to a horizontal polarization, but is not limited thereto. The first polarization and the second polarization may be any linear polarizations that are orthogonal.

[0090] The modem unit (1400) can control the beam of the first polarization or the second polarization to be steered by 2α by applying a signal to the first port (P1) or the sixth port (P6). For example, a beam having vertical polarization can be steered by +25 degrees by applying a signal to the first port (P1). Alternatively, a beam having horizontal polarization can be steered by +25 degrees by applying a signal to the sixth port (P6).

[0091] The modem unit (1400) can control the beam of the first polarization or the second polarization to be steered by α by applying a signal to the second port (P2) or the seventh port (P7). For example, by applying a signal to the second port (P2), a beam having vertical polarization can be steered by +12.5 degrees. Alternatively, by applying a signal to the seventh port (P7), a beam having horizontal polarization can be steered by +25 degrees.

[0092] The modem unit (1400) can control the beam of the first polarization or the second polarization to be steered to 0 degrees by applying a signal to the third port (P3) or the eighth port (P8). For example, a beam having vertical polarization can be steered to 0 degrees by applying a signal to the third port (P3). Alternatively, a beam having horizontal polarization can be steered to 0 degrees by applying a signal to the eighth port (P8).

[0093] The modem unit (1400) can control the beam of the first polarization or the second polarization to be steered by -α by applying a signal to the fourth port (P4) or the eighth port (P8). For example, a beam having vertical polarization can be steered by -12.5 degrees by applying a signal to the fourth port (P4). Alternatively, a beam having horizontal polarization can be steered by -12.5 degrees by applying a signal to the eighth port (P8).

[0094] The modem unit (1400) can control the beam of the first polarization or the second polarization to be steered by -2α by applying a signal to the fifth port (P5) or the tenth port (P10). For example, a beam having vertical polarization can be steered by -25 degrees by applying a signal to the fifth port (P5). Alternatively, a beam having horizontal polarization can be steered by -25 degrees by applying a signal to the tenth port (P10).

[0095] The modem unit (1400) can control signals to be simultaneously input to one port of the first input line (1210) and one port of the second input line (1310) so as to be steered with circular polarization. The modem unit (1400) can control the ports into which signals are input so that any one pair is selected from among the first to fifth pairs of the first port (P1), the sixth port (P6), the fifth port (P5), and the tenth port (P10). The modem unit (1400) can control the signal of circular polarization to be beamformed by changing any one of the selected pairs of ports.

[0096] The modem unit (1400) can control a beam having circular polarization to be steered by 2α by applying a first signal to the first port (P1) and a second signal to the sixth port (P6). For example, a beam having circular polarization can be steered by +25 degrees by applying a first signal to the first port (P1) and a second signal to the sixth port (P6).

[0097] The modem unit (1400) can control a beam having circular polarization to be steered by α by applying a first signal to the second port (P2) and a second signal to the seventh port (P7). For example, a beam having circular polarization can be steered by +12.5 degrees by applying a first signal to the second port (P2) and a second signal to the seventh port (P7).

[0098] The modem unit (1400) can control a beam of a first polarization or a second polarization to be steered to 0 degrees by applying a first signal to the third port (P3) and a second signal to the eighth port (P8). For example, a beam having a circular polarization can be steered to 0 degrees by applying a first signal to the third port (P3) and a second signal to the eighth port (P8).

[0099] The modem unit (1400) can control a beam having circular polarization to be steered by -α by applying a first signal to the fourth port (P4) and a second signal to the eighth port (P8). For example, a beam having circular polarization can be steered by -12.5 degrees by applying a first signal to the fourth port (P4) and a second signal to the eighth port (P8).

[0100] The modem unit (1400) can control a beam having circular polarization to be steered by -2α by applying a first signal to the fifth port (P5) and a second signal to the tenth port (P10). For example, a beam having circular polarization can be steered by -25 degrees by applying a first signal to the fifth port (P5) and a second signal to the tenth port (P10).

[0101] Meanwhile, the signal transmission device (1000) according to the present specification may be configured to include a plurality of dummy ports for eliminating diffuse reflection. The signal transmission device (1000) may be configured to include first dummy ports (DP11 to DP13), second dummy ports (DP21 to DP23), third dummy ports (DP31 to DP33), and fourth dummy ports (DP41 to DP43).

[0102] The first dummy ports (DP11 to DP13) may be configured to be connected to lines in an upper region of the first Rotman lens (1230). The second dummy ports (DP21 to DP23) may be configured to be connected to lines in a lower region of the first Rotman lens (1230). The upper region of the first Rotman lens (1230) corresponds to an upper region having a positive coordinate based on the Y-axis. The lower region of the first Rotman lens (1230) corresponds to a lower region having a negative coordinate based on the Y-axis.

[0103] The third dummy ports (DP31 to DP33) may be configured to be connected to lines in an upper region of the second Rotman lens (1330). The fourth dummy ports (DP41 to DP43) may be configured to be connected to lines in a lower region of the second Rotman lens (1330). The upper region of the second Rotman lens (1330) corresponds to an upper region having a positive coordinate with respect to the Y-axis. The lower region of the second Rotman lens (1330) corresponds to a lower region having a negative coordinate with respect to the Y-axis.

[0104] The number of first dummy ports (DP11 to DP13) and the number of second dummy ports (DP21 to DP23) can be set to be smaller than the number of ports (P1 to P5) of the first input line (1210). Accordingly, the number of dummy ports can be minimized while supporting multiple polarizations and eliminating diffuse reflection, thereby minimizing the length along the X-axis of the signal transmission device (1000).

[0105] The number of the third dummy ports (DP31 to DP33) and the number of the fourth dummy ports (DP41 to DP43) can be set to be smaller than the number of ports (P6 to P10) of the second input line (1310). Accordingly, the number of dummy ports can be minimized while supporting multiple polarizations and eliminating diffuse reflection, thereby minimizing the length along the X-axis of the signal transmission device (1000).

[0106] The sum of the number of the first dummy ports (DP11 to DP13) and the number of the second dummy ports (DP21 to DP23) may be set to be greater than the number of the ports (P1 to P5) of the first input line (1210). The sum of the number of the third dummy ports (DP31 to DP33) and the number of the fourth dummy ports (DP41 to DP43) may be set to be greater than the number of the ports (P6 to P10) of the second input line (1310).

[0107] Beam forming of the array antenna can be achieved when signals are applied to the ports (P1 to P5) of the first input line (1210) and the ports (P6 to P10) of the second input line (1310). Accordingly, the ports (P1 to P5) of the first input line (1210) and the ports (P6 to P10) of the second input line (1310) can be referred to as beam ports.

[0108] The plurality of patch antennas (PA1 to PA8) may include a first patch antenna (PA1) to an eighth patch antenna (PA8). A first output line (1220) may include first to eighth ports (Po1 to Po8) configured to apply signals of a first polarization to the first patch antenna (PA1) to the eighth patch antenna (PA8). A second output line (1320) may include ninth to sixteenth ports (Po9 to Po16) configured to apply signals of a second polarization to the first patch antenna (PA1) to the eighth patch antenna (PA8). The first to eighth ports (Po1 to Po8) and the ninth to sixteenth ports (Po9 to Po16) are connected to an array antenna. Therefore, the first to eighth ports (Po1 to Po8) and the ninth to sixteenth ports (Po9 to Po16) may be referred to as array ports.

[0109] Adjacent patch antennas among the first patch antenna (PA1) to the eighth patch antennas (PA8) may be arranged to be spaced apart from each other by a predetermined interval. Adjacent patch antennas among the first patch antenna (PA1) to the eighth patch antennas (PA8) may be arranged to be spaced apart from each other by a half wavelength (λ0 / 2), which is half of the wavelength (λ0) in air.

[0110] Each of the first patch antenna (PA1) to the eighth patch antennas (PA8) may be formed as a square patch antenna that is rotated 45 degrees with respect to a first axis (e.g., X-axis). An end of the first output line (1220) may be coupled to the first patch antenna (PA1) to the eighth patch antennas (PA8) at an angle of -45 degrees with respect to the first axis. An end of the second output line (1320) may be coupled to the first patch antenna (PA1) to the eighth patch antennas (PA8) at an angle of 45 degrees with respect to the first axis.

[0111] Some of the first output lines (1220) may be formed in a straight line structure, and the remaining lines may be formed in a curved structure. Some of the second first output lines (1220) may be formed in a straight line structure, and the remaining lines may be formed in a curved structure.

[0112] Among the first output lines (1220), the outermost upper and lower lines (L1, L8) may be formed in a straight structure, and the remaining lines (L2 to L7) may be formed in a curved structure. Among the second output lines (1320), the outermost upper and lower lines (L1, L8) may be formed in a straight structure, and the remaining lines (L2 to L7) may be formed in a curved structure.

[0113] The first to eighth ports (Po1 to Po8) of the first output line (1220) may be implemented to form a first polarization. The ninth to sixteenth ports (Po9 to Po16) of the second output lines (1320) may be implemented to form a second polarization. The first polarization may be set to a vertical polarization and the second polarization may be set to a horizontal polarization, but is not limited thereto. The first polarization and the second polarization may be any linear polarizations that are orthogonal.

[0114] The modem unit (1400) applies first to eighth signals in the third axis direction of the first to eighth patch antennas (PA1 to PA8) to the first to eighth ports (Po1 to Po8) so that a first polarization is formed in the first to eighth patch antennas (PA1 to PA8). The third axis direction corresponds to the X' axis direction, which is an axis rotated 45 degrees with respect to the first axis.

[0115] The modem unit (1400) applies the ninth to sixteenth signals in a fourth axis direction perpendicular to the third axis of the first to eighth patch antennas (PA1 to PA8) to the ninth to sixteenth ports (Po9 to Po16) so that a second polarization is formed in the first to eighth patch antennas (PA1 to PA8). The fourth axis direction corresponds to the 'axis direction, which is an axis rotated 45 degrees with respect to the second axis direction.

[0116] The modem unit (1400) can apply first to eighth signals to the first to eighth ports (Po1 to Po8) and apply ninth to sixteenth signals to the ninth to sixteenth ports (Po9 to Po16) so that circular polarization is formed in the first to eighth patch antennas (PA1 to PA8).

[0117] Meanwhile, the output lines of the signal transmission device according to the present specification may be formed in a linear or curved structure. In this regard, Fig. 8 illustrates output lines of the signal transmission device formed in a linear or curved structure. Fig. 9 illustrates phase values ​​for each frequency according to the slope angle of the curve in the output lines of Fig. 8.

[0118] Referring to FIGS. 7 and 8(a), the first line (L1) of the first output line (1220) may be formed as a straight line having a length of 3 mm and a width of 145 μm. The first line (L1) having a length of 3 mm and a width of 145 μm has an insertion loss of 0.51 dB at a center frequency of 160 GHz. Referring to FIGS. 7 and 8(b), the second line (L2) of the first output line (1220) may be formed as a curve having a length of 3 mm, a width of 145 μm, and an inclination angle (A1) of 10 degrees. The second line (L2) having a length of 3 mm, a width of 145 μm, and an inclination angle (A1) of 10 degrees has an insertion loss of 0.86 dB at a center frequency of 160 GHz.

[0119] Referring to FIGS. 7 and 8(c), the third line (L3) of the first output line (1220) can be formed as a straight line having a length of 3 mm, a width of 145 μm, and an inclination angle (A2) of 20 degrees. The third line (L3) having a length of 3 mm, a width of 145 μm, and an inclination angle (A2) of 20 degrees has an insertion loss of 1.41 dB at a center frequency of 160 GHz. Referring to FIGS. 7 and 8(d), the fourth line (L4) of the first output line (1220) can be formed as a curve having a length of 3 mm, a width of 145 μm, and an inclination angle (A3) of 30 degrees. The fourth line (L4) with a length of 3 mm, a width of 145 um and an inclination angle of 30 degrees (A3) has an insertion loss of 1.72 dB at a center frequency of 160 GHz.

[0120] Referring to FIGS. 6(a), 8, and 9, the first line (L1) having an inclination angle of 0 degrees has a phase value of -95 degrees at 160 GHz. The second line (L2) having an inclination angle (A1) of 10 degrees has a phase value of -151 degrees at 160 GHz. The third line (L3) having an inclination angle (A2) of 20 degrees has a phase value of -284 degrees at 160 GHz. The fourth line (L4) having an inclination angle (A3) of 30 degrees has a phase value of -425 degrees at 160 GHz.

[0121] Referring to FIGS. 4 to 6 and 8, when designing the first and second Rotman lenses (1230, 1330), the output lines (1220, 1320) may be designed as meander lines having a curved structure in order to transmit a specific phase value of a signal to the antenna unit (1100). The first and second output lines (1220, 1320) formed as meander lines having a curved structure may be connected to respective antenna elements of the array antenna of the antenna unit (1100). The ends of the first and second output lines (1220, 1320) connected to respective antenna elements of the array antenna of the antenna unit (1100) may form array ports.

[0122] In this regard, signals of the same phase or different phases may be applied to each antenna element of the antenna unit (1100) depending on which port among the first and second input lines (1210, 1310) the signal is applied to. The signal applied to each antenna element of the antenna unit (1100) may be variable with different phase values.

[0123] Compared to the first line (L1) of a straight structure, the fourth line (L4) of a curved structure with an inclination angle (A3) of 30 degrees has an insertion loss that increases by about 1.2 dB. However, the first and second output lines (1210, 1310) are formed with lines having different inclination angles in a symmetrical structure in the Y-axis direction. Accordingly, the magnitude of the signal applied to each antenna element of the antenna unit (1100) is also formed in a symmetrical structure in the Y-axis direction, and the beam pattern of the antenna unit (1100) is also formed in a symmetrical structure. In this regard, FIG. 10 illustrates beam patterns of the antenna unit of the signal transmission device of FIG. 4.

[0124] Referring to FIGS. 4 and 10, when a signal is applied to the third or eighth port (P3, P8) of the first or second input line (1210, 1310), a beam pattern (BP3) radiated through the antenna unit (1100) is formed to steer at 0 degrees. The beam pattern (BP3) steered at 0 degrees is formed in a left-right symmetrical structure. The magnitude of the signal applied to each antenna element of the antenna unit (1100) is also formed in a symmetrical structure in the Y-axis direction, so that the beam pattern of the antenna unit (1100) is also formed in a symmetrical structure in the Y-axis direction. The peak gain of the antenna unit (1100) implemented as a 1x8 array antenna has a value of 15.1 dBi.

[0125] When a signal is applied to the first or sixth port (P1, P6) of the first or second input line (1210, 1310), the beam pattern (BP1) radiated through the antenna unit (1100) is formed to steer at 30 degrees. The peak gain of the antenna unit (1100) implemented as a 1x8 array antenna has a value of 13.6 dBi. When a signal is applied to the fifth or tenth port (P5, P10) of the first or second input line (1210, 1310), the beam pattern (BP5) radiated through the antenna unit (1100) is formed to steer at -30 degrees. The peak gain of the antenna unit (1100) implemented as a 1x8 array antenna has a value of 13.1 dBi. The beam pattern (BP1) and the beam pattern (BP5) are formed in a nearly symmetrical structure with respect to the Y-axis, and their peak gains also have similar values.

[0126] When a signal is applied to the second or seventh port (P2, P7) of the first or second input line (1210, 1310), the beam pattern (BP2) radiated through the antenna unit (1100) is formed to steer at 15 degrees. The peak gain of the antenna unit (1100) implemented as a 1x8 array antenna has a value of 14.3 dBi. When a signal is applied to the fourth or ninth port (P4, P9) of the first or second input line (1210, 1310), the beam pattern (BP4) radiated through the antenna unit (1100) is formed to steer at -15 degrees. The peak gain of the antenna unit (1100) implemented as a 1x8 array antenna has a value of 14.1 dBi. The beam pattern (BP2) and the beam pattern (BP4) are formed in a nearly symmetrical structure with respect to the Y-axis, and their peak gains also have similar values.

[0127] Meanwhile, a signal transmission device according to another embodiment of the present specification can be combined with a two-dimensional array antenna to implement beamforming in the horizontal and vertical axes. In this regard,

[0128] Fig. 11 illustrates a signal transmission device including a plurality of Rotman lenses and a two-dimensional array antenna structure according to the present specification. Fig. 12 is an enlarged view of a portion of the two-dimensional array antenna of Fig. 11.

[0129] Referring to FIGS. 11 and 12, a signal transmission device (1000b) including a plurality of Rotman lenses can be configured to include an antenna unit (1100b), a first signal line (1200), and a second signal line (1300).

[0130] The antenna unit (1100b) may include a plurality of patch antennas (PA11-P1A8 to PA81-PA88). The antenna unit (1100) may be a two-dimensional array antenna composed of a plurality of patch antennas (PA11-P1A18 to PA81-PA88) spaced apart from each other in the horizontal and vertical axes. The antenna unit (1100) is not limited to a 1x8 array antenna, and may be configured to include any number of antenna elements.

[0131] As described above, the first signal line (1200) may be composed of a first input line (1210), a first output line (1220), and a first Rotman lens (1230). The second signal line (1300) may be composed of a second input line (1310), a second output line (1320), and a second Rotman lens (1330).

[0132] The plurality of patch antennas (PA11-P1A18 to PA81-PA88) may include first patch antennas (PA11-P1A18) to eighth patch antennas (PA81-PA88) arranged in a two-dimensional structure. The first output line (1220) may include first to eighth ports (Po1 to Po8) formed to apply signals of a first polarization to the first patch antenna (PA1) to the eighth patch antenna (PA8). The second output line (1320) may include ninth to sixteenth ports (Po9 to Po16) formed to apply signals of a second polarization to the first patch antenna (PA1) to the eighth patch antenna (PA8).

[0133] Each of the first patch antennas (PA11-P1A18) to the eighth patch antennas (PA81-PA88) may include a plurality of antenna elements spaced apart in the first axial direction. The patch antenna elements adjacent in the first axial direction of each of the first patch antennas (PA11-P1A18) to the eighth patch antennas (PA81-PA88) may be spaced apart from each other by a length corresponding to a wavelength (λg) corresponding to an operating frequency of the antenna unit (1100b). Accordingly, the adjacent antenna elements arranged in the X-axis direction, which is the first axial direction, may be fed in a serial feeding manner.

[0134] Among the first patch antenna (PA1) to the eighth patch antennas (PA8), the patch antennas adjacent in the Y-axis direction, which is the second axis direction, may be arranged at a predetermined interval. Among the first patch antenna (PA1) to the eighth patch antennas (PA8), the patch antennas adjacent in the Y-axis direction may be arranged at a half-wavelength (λ0 / 2) interval.

[0135] In this regard, a signal transmission device (1000) having a two-dimensional array antenna structure may further include a first feed line (FL1) and a second feed line (FL2). The first feed line (FL1) may extend from the first output line (1220) to the rightmost patch antenna element. The second feed line (FL2) may extend from the second output line (1320) to the leftmost patch antenna element.

[0136] The modem unit (1400) can control the polarization of the antenna unit (1100b) by applying a signal to the first feed line (FL1) and / or the second feed line (FL2). The modem unit (1400) can control the antenna unit (1100b) to radiate a signal of the first polarization by applying a first signal to the first feed line (FL1). The modem unit (1400) can control the antenna unit (1100b) to radiate a signal of the second polarization perpendicular to the first polarization by applying a second signal to the second feed line (FL1). The modem unit (1400) can control the antenna unit (1100b) to radiate a signal of the circular polarization by applying a first signal to the first feed line (F1) and a second signal to the second feed line (F2).

[0137] Meanwhile, a signal transmission device having a one-dimensional or two-dimensional array antenna can implement different polarizations and beam patterns depending on which port among the first and second input lines (1210, 1310) a signal is applied to. In this regard, FIGS. 13 and 14 illustrate beam patterns and axial ratios when a signal is applied to the third or eighth port of the first or second input lines of the signal transmission device of FIG. 11.

[0138] Referring to FIGS. 11 and 13(a), when a signal is applied to the third port (P3) of the first input line (1210), a beam pattern steered at 0 degrees with vertical polarization is formed. The beam peak of the vertical polarization signal in the 0 degree direction is 19.3 dBi, and the horizontal polarization signal level in the 0 degree direction is -8.2 dBi. Therefore, the cross-polarization separation between the vertical / horizontal signals has a value of 27 dBc or more.

[0139] Referring to FIG. 11, FIG. 13(a), and FIG. 13(b), the axial ratio, which is the ratio of the vertical polarization signal to the horizontal signal, has a value of approximately 50 dB in the front direction. Therefore, when a signal is applied to the third port (P3) of the first input line (1210), a vertical polarization signal is mainly radiated.

[0140] Referring to FIGS. 11 and 14(a), when a signal is applied to the eighth port (P8) of the second input line (1310), a beam pattern steered at 0 degrees with horizontal polarization is formed. The beam peak of the horizontal polarization signal in the 0 degree direction is 19.2 dBi, and the vertical polarization signal level in the 0 degree direction is -9.1 dBi. Therefore, the cross-polarization separation between the horizontal / vertical signals has a value of 28 dBc or more.

[0141] Referring to FIG. 11, FIG. 14(a), and FIG. 14(b), the axial ratio, which is the ratio of the horizontal polarization signal to the vertical signal, has a value of 50 dB or more in the front direction. Therefore, when a signal is applied to the eighth port (P8) of the first input line (1210), a horizontal polarization signal is mainly radiated.

[0142] Meanwhile, it can be configured to radiate a circularly polarized signal by simultaneously applying signals to the first and second input lines (1210, 1310). In this regard, FIG. 15 illustrates beam patterns when signals are simultaneously applied to the third and eighth ports of the first and second input lines of the signal transmission device of FIG. 11.

[0143] Referring to FIG. 11 and FIG. 15(a), when signals are simultaneously applied to the third port (P3) of the first input line (1210) and the eighth port (P8) of the second input line (1310), a beam pattern steering at 0 degrees with circular polarization is formed. In the 0 degree direction, the vertical polarization signal level and the horizontal signal level are almost similar at 16.10 dBi and 16.09 dBi. Therefore, the circular polarization signal level in the 0 degree direction has a value of 19.11 dBi.

[0144] Referring to FIG. 11, FIG. 15(a), and FIG. 15(b), the axial ratio, which is the ratio of the vertical polarization signal to the horizontal polarization signal, has a value of 3 dB or less between -20 and 18 degrees. In FIG. 14(a), the main beam associated with the 3 dB beam width of the circular polarization signal is formed to be ±10 degrees or less. Therefore, the axial ratio has a value of 3 dB or less within the area where the main beam is formed, thereby satisfying the circular polarization performance requirement.

[0145] As described above, a signal transmission device having a one-dimensional or two-dimensional array antenna can implement different polarizations and beam patterns depending on which port among the first and second input lines (1210, 1310) a signal is applied to. In this regard, FIG. 16 illustrates gains, beam steering angles, and beam patterns according to signal application to each port of the first input line of FIG. 11.

[0146] Fig. 16(a) shows the gain and beam steering angle according to signal application to each port of the first input line of Fig. 11. Figs. 16(b) to 16(d) show beam patterns when signals are applied to the first, third, and fifth ports.

[0147] Referring to FIGS. 11 and 16, when a signal is applied to the first port (P1) of the first input line (1210), a vertically polarized beam having a gain of 16.6 dBi and a beam steering angle of 25 degrees is formed. When a signal is applied to the third port (P3) of the first input line (1210), a vertically polarized beam having a gain of 19.3 dBi and a beam steering angle of 0 degrees is formed. When a signal is applied to the fifth port (P5) of the first input line (1210), a vertically polarized beam having a gain of 17.0 dBi and a beam steering angle of -25 degrees is formed. Referring to FIGS. 4, 11, and 16, a vertically polarized beam can be formed while maintaining a scan loss value of 3 dB or less within a beam coverage area of ​​±25 degrees.

[0148] Figure 17 shows the gain, beam steering angle, and beam patterns according to signal application to each port of the second input line of Figure 11.

[0149] Fig. 17(a) shows the gain and beam steering angle according to signal application to each port of the second input line of Fig. 11. Figs. 17(b) to 17(d) show beam patterns when signals are applied to ports 6, 8, and 10.

[0150] Referring to FIGS. 11 and 17, when a signal is applied to the sixth port (P6) of the second input line (1310), a horizontal polarization beam having a gain of 17.4 dBi and a beam steering angle of 25 degrees is formed. When a signal is applied to the eighth port (P8) of the second input line (1310), a horizontal polarization beam having a gain of 19.1 dBi and a beam steering angle of 0 degrees is formed. When a signal is applied to the tenth port (P10) of the second input line (1310), a horizontal polarization beam having a gain of 16.3 dBi and a beam steering angle of -25 degrees is formed. Referring to FIGS. 4, 11, and 17, a horizontal polarization beam can be formed while maintaining a scan loss value of 3 dB or less within a beam coverage area of ​​±25 degrees.

[0151] Figure 18 shows the gain, beam steering angle, and beam patterns according to signal application to each port of the first and second input lines of Figure 11.

[0152] Fig. 18(a) shows the gain and beam steering angle according to signal application to each port of the first and second input lines of Fig. 11. Fig. 18(b) shows a beam pattern when a signal is applied simultaneously to the first port (P1) of the first input line (1210) and the sixth port (P6) of the second input line (1310). Fig. 18(c) shows a beam pattern when a signal is applied simultaneously to the third port (P3) of the first input line (1210) and the eighth port (P8) of the second input line (1310). Fig. 18(d) shows a beam pattern when a signal is applied simultaneously to the fifth port (P5) of the first input line (1210) and the tenth port (P10) of the second input line (1310).

[0153] Referring to FIGS. 11 and 18, when a signal is applied to the first and sixth ports (P1, P6) of the first and second input lines (1210, 1310), a circularly polarized beam having a gain of 17.0 dBi and a beam steering angle of 25 degrees is formed. When a signal is applied to the third and eighth ports (P3, P8) of the first and second input lines (1210, 1310), a circularly polarized beam having a gain of 19.1 dBi and a beam steering angle of 0 degrees is formed. When a signal is applied to the fifth and tenth ports (P5, P10) of the first and second input lines (1210, 1310), a circularly polarized beam having a gain of 16.3 dBi and a beam steering angle of -25 degrees is formed. Referring to FIG. 4, FIG. 11 and FIG. 18, a circular polarization beam can be formed while maintaining a scan loss value of 3 dB or less within a beam coverage area of ​​±25 degrees.

[0154] Meanwhile, in the signal transmission device according to the present specification, signals may be applied to multiple ports to form two or more multi-beam patterns in different directions in addition to a circularly polarized beam pattern. In this regard, FIG. 19 illustrates a multi-beam pattern when a signal is applied to one port of a first input line and one port of a second input line.

[0155] Referring to FIG. 4, FIG. 11, and FIG. 19(a), when signals are simultaneously applied to the third port (P3) of the first input line (1210) and the sixth port (P6) of the second input line (1310), a multi-beam pattern is shown. A beam in the 0-degree direction is formed by the signal applied to the third port (P3) of the first input line (1210), and a beam in the 25-degree direction is formed by the signal applied to the sixth port (P6) of the second input line (1310). The peak gain of the beam radiated through the antenna unit (1100b) of the two-dimensional array antenna is 16.8 dBi.

[0156] Referring to FIG. 4, FIG. 11, and FIG. 19(b), when signals are simultaneously applied to the third port (P3) of the first input line (1210) and the seventh port (P7) of the second input line (1310), a multi-beam pattern is shown. A beam having a vertical polarization in the 0 degree direction is formed by the signal applied to the third port (P3) of the first input line (1210), and a beam having a horizontal polarization in the 12.5 degree direction is formed by the signal applied to the seventh port (P7) of the second input line (1310). The peak gain of the beam radiated through the antenna unit (1100b) of the two-dimensional array antenna is 16.15 dBi.

[0157] Referring to FIG. 4, FIG. 11, and FIG. 19(c), when signals are simultaneously applied to the first port (P1) of the first input line (1210) and the ninth port (P9) of the second input line (1310), a multi-beam pattern is shown. A beam having a vertical polarization in a 25-degree direction is formed by the signal applied to the first port (P1) of the first input line (1210), and a beam having a horizontal polarization in a -12.5-degree direction is formed by the signal applied to the ninth port (P9) of the second input line (1310). The peak gain of the beam radiated through the antenna unit (1100b) of the two-dimensional array antenna is 15.59 dBi.

[0158] Referring to FIG. 4, FIG. 11, and FIG. 19(d), when signals are simultaneously applied to the first port (P1) of the first input line (1210) and the tenth port (P10) of the second input line (1310), a multi-beam pattern is shown. A beam having a vertical polarization in a 25-degree direction is formed by the signal applied to the first port (P1) of the first input line (1210), and a beam having a horizontal polarization in a 25-degree direction is formed by the signal applied to the tenth port (P10) of the second input line (1310). The peak gain of the beam radiated through the antenna unit (1100b) of the two-dimensional array antenna is 14.97 dBi.

[0159] In this regard, when signals are applied to ports at corresponding positions in the first and second input lines (1210, 1310), beam patterns of circular polarization are formed. Meanwhile, when signals are applied to ports at different positions in the first and second input lines (1210), beams having vertical polarization and beams having horizontal polarization are formed in different directions.

[0160] On the other hand, when two ports are selected from the first input line (1210), two beams having vertical polarization can be formed. In addition, when two ports are selected from the second input line (1310), two beams having horizontal polarization can be formed. However, when forming two beams having vertical polarization, two signals are applied to the same first Rotman lens (1230), resulting in mutual interference between the signals. In addition, when forming two beams having horizontal polarization, two signals are applied to the same second Rotman lens (1330), resulting in mutual interference between the signals. The mutual interference between the signals can cause beam pattern distortion, gain reduction, and side-lobe increase.

[0161] Therefore, in order to reduce interference between two signals, one port from the first input line (1210) and one port from the second input line (1310) can be selected to form a multi-beam. Referring to FIGS. 4, 11, and 19, the operation of the signal transmission device (1000) implemented as a multi-beam antenna will be described. The modem unit (1400) of the signal transmission device (1000) can apply a first signal to any one of the first port (P1) to the fifth port (P5) of the first input line (1210) to form a first beam of the first polarization to be directed at a first angle. The modem unit (1400) can form a first beam of a first polarization, and can apply a second signal to any one of the sixth port (P6) to the tenth port (P10) of the second input line (1310) to form a second beam of a second polarization directed at a second angle. The second angle, which is a steering angle of the second beam of the second polarization, can be formed at a different angle from the first angle, which is a steering angle of the first beam of the first polarization.

[0162] Meanwhile, it is also possible to form multiple beams by selecting M ports for one of the first and second input lines (1210, 1310) and N ports for the remaining lines. In this regard, Fig. 20 shows beam patterns when M ports are selected for one of the first and second input lines and N ports for the remaining lines.

[0163] Referring to FIG. 4, FIG. 11, and FIG. 20(a), when signals are simultaneously applied to the first and third ports (P1, P3) of the first input line (1210) and the seventh port (P7) of the second input line (1310), a multi-beam pattern is shown. The signals applied to the first and third ports (P1, P3) of the first input line (1210) form beams in the 25 degree and 0 degree directions with vertical polarization, while the signals applied to the seventh port (P7) of the second input line (1310) form beams in the 12.5 degree direction with horizontal polarization. The peak gain of the beam radiated through the antenna unit (1100b) of the two-dimensional array antenna is 14.21 dBi.

[0164] Referring to FIG. 4, FIG. 11, and FIG. 20(b), when signals are simultaneously applied to the first and fifth ports (P1, P5) of the first input line (1210) and the eighth port (P8) of the second input line (1310), a multi-beam pattern is shown. The signals applied to the first and fifth ports (P1, P5) of the first input line (1210) form beams in the 25 degree and -25 degree directions with vertical polarization, while the signals applied to the eighth port (P8) of the second input line (1310) form a beam in the 0 degree direction with horizontal polarization. The peak gain of the beam radiated through the antenna unit (1100b) of the two-dimensional array antenna is 13.67 dBi.

[0165] Referring to FIG. 4, FIG. 11, and FIG. 20(c), when signals are simultaneously applied to the first, third, and fifth ports (P1, P3, P5) of the first input line (1210) and the seventh and ninth ports (P7, P9) of the second input line (1310), a multi-beam pattern is exhibited. By the signals applied to the first, third, and fifth ports (P1, P3, P5) of the first input line (1210), beams having vertical polarization in the directions of 25 degrees, 0 degrees, and -25 degrees are formed, and by the signals applied to the seventh and ninth ports (P7, P9) of the second input line (1310), beams having horizontal polarization in the directions of -12.5 degrees and 12.5 degrees are formed. The peak gain of the beam radiated through the antenna unit (1100b) of the two-dimensional array antenna is 12.0 dBi.

[0166] Referring to FIGS. 4, 11, and 20, the operation of a signal transmission device (1000) implemented as a multi-beam antenna will be described. The modem unit (1400) of the signal transmission device (1000) can form first beams of a first polarization to point at first angles by applying first signals to one or more ports among the first port (P1) to the fifth port (P5) of the first input line (1210). While forming the first beams of the first polarization, the modem unit (1400) can form second beams of a second polarization to point at second angles by applying a second signal to one or more ports among the sixth port (P6) to the tenth port (P10) of the second input line (1310). The second angles, which are steering angles of the second beams of the second polarization, can be formed at different angles from the first angles, which are steering angles of the first beams of the first polarization.

[0167] The above describes a signal transmission device having a one-dimensional or two-dimensional array antenna and a Rotman lens according to the present specification. The technical effects of the signal transmission device having a one-dimensional or two-dimensional array antenna and a Rotman lens according to the present specification are as follows.

[0168] According to an embodiment, a beam pattern of vertical / horizontal / circular polarization can be formed through a signal transmission device that radiates a multi-polarization signal.

[0169] According to an embodiment, a vertical / horizontal / circular polarization tunable beam-switching solution can be proposed by implementing a Rotman lens-based signal generation circuit network capable of imparting two or more polarization characteristics to an array antenna.

[0170] According to an embodiment, a signal transmission device that radiates a vertical / horizontal / circularly polarized variable multi-polarized signal in a frequency band of millimeter waves or higher can be implemented.

[0171] According to an embodiment, a multi-signal generation circuit network based on a multi-Rotman lens capable of applying vertical or horizontal polarization signals can be used to share array antennas so that signals can be supplied to the array antennas independently / mutually. Accordingly, signals can be selectively applied according to the polarization characteristics to be radiated, thereby implementing vertical / horizontal / circular polarization.

[0172] According to the embodiment, selective beam steering for vertical / horizontal / circular polarization is possible, and radiation performance control such as beam-steering / beam-forming / beam-broadening is possible.

[0173] According to an embodiment, by improving the antenna radiation performance of a multi-beam generation mode using multiple Rotman lenses, it is possible to improve multi-beam operation characteristics that are difficult to implement with a beamformer such as a single Rotman lens or a Butler matrix.

[0174] According to an embodiment, in a signal transmission device that emits a multi-polarization signal capable of beam synthesis having two or more polarization characteristics, beam forming can be provided in a uniaxial direction by changing the ports of input lines connected to a Rotman lens.

[0175] According to an embodiment, in a signal transmission device that emits a multi-polarization signal capable of synthesizing beams having two or more polarization characteristics, while forming multi-beams, signals are applied to ports in different areas to reduce mutual interference between the multi-beams.

[0176] Further scope of the applicability of this disclosure will become apparent from the detailed description below. However, since various changes and modifications within the spirit and scope of this disclosure will become apparent to those skilled in the art, it should be understood that the detailed description and specific embodiments, such as the preferred embodiments of this disclosure, are given by way of example only. The detailed description should not be construed as limiting in any respect but rather as illustrative. The scope of this disclosure should be determined by a reasonable interpretation of the appended claims, and all changes coming within the scope of equivalents of this disclosure are intended to be embraced therein.

Claims

1. In a signal transmission device including a plurality of Rotman lenses, An antenna section having multiple patch antennas; a first signal line electrically connected to each of the plurality of patch antennas to operate in the first polarization; and The first signal line is composed of a first input line connected to the modem unit, a first output line connected to the antenna unit, and a first Rotman lens arranged between the first input line and the first output line. A second signal line electrically connected to each of the plurality of patch antennas so as to operate in a second polarization; The second signal line is composed of a second input line connected to the modem unit, a second output line connected to the antenna unit, and a second Rotman lens arranged between the second input line and the second output line. A signal transmission device in which the signal transmission length of the second signal line is formed to be longer by 1 / 4 of the wavelength (λg) than the signal transmission length of the first signal line.

2. In paragraph 1, One side and the other side of the first Rotman lens are connected to the first input line and the first output line, One side and the other side of the second Rotman lens are connected to the second output line and the second input line, A signal transmission device, wherein the second Rotman lens is formed in a symmetrical structure with respect to the first Rotman lens with respect to the vertical axis of the substrate.

3. In paragraph 1, The first input line includes a first port to a fifth port connected to one side of the first Rotman lens, The second input line includes a sixth to tenth port connected to the other side of the second Rotman lens, The above modem part, Controlling the signal of the first polarization to be beam-formed by changing the port through which the signal is input to any one of the first port to the fifth port, A signal transmission device that controls the signal of the second polarization to be beam-formed by changing the port through which the signal is input to any one of the sixth port to the tenth port.

4. In paragraph 3, The above modem part, By applying the signal to the first port or the sixth port, the beam of the first polarization or the second polarization is controlled to be steered by 2α, By applying the signal to the second port or the seventh port, the beam of the first polarization or the second polarization is controlled to be steered by α, By applying the signal to the third port or the eighth port, the beam of the first polarization or the second polarization is controlled to be steered to 0 degrees, By applying the signal to the fourth port or the ninth port, the beam of the first polarization or the second polarization is controlled to be steered by -α, A signal transmission device that controls a beam of the first polarization or the second polarization to be steered by -2α by applying the signal to the fifth port or the tenth port.

5. In paragraph 3, The above modem part, Controlling the ports into which the signal is input so that one pair is selected among the first to fifth pairs of the first port, the sixth port, the fifth port, and the tenth port, A signal transmission device that controls a circularly polarized signal to be beam formed by changing any one of the pairs of ports selected above.

6. In paragraph 5, The above modem part, By applying a first signal to the first port and a second signal to the sixth port, the beam of circular polarization is controlled to be steered by 2α, By applying a first signal to the second port and a second signal to the seventh port, the beam of circular polarization is controlled to be steered by α, By applying a first signal to the third port and a second signal to the eighth port, the beam of circular polarization is controlled to be steered to 0 degrees. By applying a first signal to the fourth port and a second signal to the ninth port, the beam of circular polarization is controlled to be steered by -α, A signal transmission device that controls the circularly polarized beam to be steered by -2α by applying a first signal to the fifth port and a second signal to the ninth port.

7. In paragraph 5, First dummy ports connected to lines in the upper region of the first Rotman lens; Second dummy ports connected to lines in the lower region of the first Rotman lens; Third dummy ports connected to the lines in the upper region of the second Rotman lens; and A signal transmission device comprising fourth dummy ports connected to lines in the lower region of the second Rotman lens.

8. In paragraph 7, The number of the first dummy ports and the number of the second dummy ports are smaller than the number of ports of the first input line, The number of the third dummy ports and the number of the fourth dummy ports are smaller than the number of ports of the first input line, The sum of the number of the first dummy ports and the number of the second dummy ports is greater than the number of ports of the first input line, A signal transmission device, characterized in that the sum of the number of the third dummy ports and the number of the fourth dummy ports is greater than the number of ports of the first input line.

9. In paragraph 5, The above plurality of patch antennas include a first patch antenna to an eighth patch antenna, The first output line includes first to eighth ports formed to apply signals of a first polarization to the first to eighth patch antennas, A signal transmission device, wherein the second output line includes ninth to sixteenth ports formed to apply signals of a second polarization to the first to eighth patch antennas.

10. In paragraph 9, Each of the first to eighth patch antennas is formed as a square patch antenna rotated 45 degrees around the first axis, The end of the first output line is coupled to the first patch antenna to the eighth patch antenna at an angle of -45 degrees with respect to the first axis, A signal transmission device, wherein an end of the second output line is coupled to the first patch antenna to the eighth patch antenna at an angle of 45 degrees with respect to the first axis.

11. In paragraph 9, Among the first output lines, the outermost upper and lower lines are formed in a straight line structure, and the remaining lines are formed in a curved structure. A signal transmission device, wherein the upper and lower outermost lines among the second output lines are formed in a straight structure and the remaining lines are formed in a curved structure.

12. In paragraph 10, The above modem part, The first to eighth signals are applied in the third axis direction of the first to eighth patch antennas to the first to eighth ports so that a first polarization is formed in the first to eighth patch antennas. The 9th to 16th ports are configured to apply the 9th to 16th signals in a 4th axis direction perpendicular to the 3rd axis of the 1st to 8th patch antennas, thereby forming a second polarization in the 1st to 8th patch antennas. The first to eighth signals are applied to the first to eighth ports, and the ninth to sixteenth signals are applied to the ninth port to the sixteenth photon, so that circular polarization is formed in the first to eighth patch antennas. A signal transmission device, wherein the third axis direction is the direction of an axis rotated 45 degrees with respect to the first axis, and the fourth axis direction is the direction of an axis rotated 45 degrees with respect to the second axis.

13. In paragraph 4, The above modem part, By applying a first signal to any one of the first to fifth ports, a first beam of a first polarization is formed to be directed at a first angle, A signal transmission device that forms a second beam of a second polarization by applying a second signal to any one of the sixth to tenth ports while forming the first beam, to direct the second beam at a second angle different from the first angle.

14. In paragraph 13, The above modem part, Applying first signals to one or more of the first to fifth ports, thereby forming first beams of a first polarization directed at first angles, A signal transmission device that forms second beams of a second polarization by applying second signals to at least one of the sixth to tenth ports while forming the first beams so as to direct second angles different from the first angles.

15. In paragraph 4, The first output line includes first to eighth ports connected to the other side of the first Rotman lens, The second output line includes ports 9 to 16 connected to one side of the second Rotman lens, The above plurality of patch antennas include first to eighth patch antennas arranged in a two-dimensional structure, A signal transmission device, wherein each of the first patch antenna to the eighth patch antenna includes a plurality of patch antenna elements spaced apart in the first axial direction.

16. In paragraph 15, A signal transmission device, wherein the patch antenna elements adjacent to each other in the first axial direction of each of the first to eighth patch antennas are arranged spaced apart from each other by a length corresponding to a wavelength corresponding to the operating frequency of the antenna unit.

17. In paragraph 16, A first feed line extending from the first output line to the rightmost patch antenna element; and A signal transmission device further comprising a second feed line extending from the second output line to the leftmost patch antenna element.

18. In paragraph 17, The above modem part, By applying a first signal to the first feed line, the antenna portion is controlled to radiate a signal of the first polarization, By applying a second signal to the second feed line, the antenna portion is controlled to radiate a signal of the second polarization, A signal transmission device that controls the antenna portion to radiate a signal of the circular polarization by applying a first signal to the first feed line and a second signal to the second feed line.

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