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RU-2861329-C2 - DUAL-BAND DUAL-POLARISATION PLANAR ANTENNA WITH SHARED APERTURE BASED ON "DOUBLE CROSS" WAVEGUIDE STRUCTURE

RU2861329C2RU 2861329 C2RU2861329 C2RU 2861329C2RU-2861329-C2

Abstract

FIELD: antennas. SUBSTANCE: invention relates to a dual-band dual-polarisation planar antenna with a shared aperture based on a "double cross" waveguide structure. The proposed antenna comprises: a radiating array, a first dielectric plate, a K-band metal back plate, a second dielectric plate, a Ka-band metal back plate, a Ka-band waveguide feed network and a K-band slot waveguide feed network, which are stacked from top to bottom. A radiating unit of the radiating array contains two parallel transverse radiating structures. The radiating array, the first dielectric plate and the K-band metal back plate form an air microstrip K-band feed network. The K-band metal back plate, the second dielectric plate and the Ka-band metal back plate form an air microstrip Ka-band feed network, thus forming a hybrid feed network from the air microstrip and waveguide feed networks. EFFECT: creating a dual-band dual-polarisation planar antenna with a shared aperture based on a "double cross" waveguide structure, which solves such problems as the interdependent design of receive/transmit bands in planar dual-polarisation dual-band K/Ka shared-aperture antennas and the tendency to form significant diffraction lobes in high bands, thereby providing an effective shared-aperture design in the K/Ka band with excellent radiation pattern envelope characteristics and portability. 10 cl, 14 dwg

Inventors

  • LIN, Hu
  • JIA, Xin
  • YUAN, Long
  • WEN, ZHONG
  • MIAO, Youxin

Dates

Publication Date
20260504
Application Date
20230816
Priority Date
20230504

Claims (14)

  1. 1. A dual-band, dual-polarization, common-aperture planar antenna based on a double-cross waveguide structure, characterized in that it comprises, stacked from top to bottom: a radiating array (10), a first dielectric plate (11), a K-band metal back plate (12), a second dielectric plate (13), a Ka-band metal back plate (14), a Ka-band waveguide feeder network (15), and a K-band waveguide feeder network (16);
  2. wherein the radiating array (10) comprises a plurality of radiating units (19) arranged in a rectangular array, and each radiating unit (19) includes one radiating unit (17) with an open waveguide in the K-band and two radiating units (18) with an open waveguide in the Ka-band, orthogonal to each other and forming two parallel transverse radiating structures;
  3. wherein the first dielectric plate (11) is provided with a plurality of K-band microstrip lines (31) arranged in the form of a rectangular array, wherein the metal grooves on the lower surface of the radiating array (10) and the metal grooves on the upper surface of the K-band metal back plate (12) form a plurality of first air microstrip cavities corresponding to the K-band microstrip lines (31), wherein the first air microstrip cavities, along with the first dielectric plate (11) and the K-band microstrip lines (31) arranged in the first air microstrip cavities, form an air microstrip feeder network of the K-band, wherein the air microstrip feeder network of the K-band includes a plurality of first air microstrip waveguide units (20) connected in a multi-level parallel configuration, matched and connected to radiating units (19), wherein the first air microstrip waveguide unit (20) includes one K-band waveguide structure (21) and two upper Ka-band waveguide structures (22), orthogonal to the first, forming two parallel transverse waveguide structures, and in which the transition section (311) of the branch end of the K-band microstrip line (31) is located inside the K-band waveguide structure (21);
  4. wherein the second dielectric plate (13) is provided with a plurality of Ka-band microstrip lines (310) arranged in the form of a rectangular array, wherein two Ka-band microstrip lines (310) form a pair and correspond to one K-band microstrip line (31), wherein the metal grooves on the lower surface of the K-band metal back plate (12) and the metal grooves on the upper surface of the Ka-band metal back plate (14) form a plurality of second air cavities, each of which is matched with each pair of Ka-band microstrip lines (310), wherein the second air cavities together with the second dielectric plate (13) and the Ka-band microstrip lines (310) arranged in the second air cavities form an air microstrip feeder network of the Ka-band, wherein the air the Ka-band microstrip feeder network includes a plurality of second airborne microstrip waveguide units (26) connected in a multi-level parallel configuration, in which the second airborne microstrip waveguide unit (26) includes one lower Ka-band waveguide structure (27) matching and connecting with the corresponding upper Ka-band waveguide structure(s) (22), and in which the transition section (3101) of the Ka-band branch end of the Ka-band microstrip line (310) is located in the lower Ka-band waveguide structure (27);
  5. wherein the Ka-band waveguide feeder network (15) includes a multi-level parallel power distribution network structure, where each smallest branch end is connected upward to a Ka-band microstrip combining end of each Ka-band microstrip line (310), respectively, wherein the K-band slot waveguide based feeder network (16) includes a multi-level parallel network slot waveguide structure, where each smallest branch end is connected upward to a combining end (314) of each K-band microstrip line (31), wherein the combining end of the multi-level parallel power distribution network structure is configured to be connected downward to a boost converter BUC, and the combining end of the multi-level parallel network slot waveguide structure is configured to be connected downward to a low-noise converter LNB.
  6. 2. A dual-band, dual-polarization, common-aperture planar antenna based on a double-cross waveguide structure according to claim 1, characterized in that the K-band microstrip line (31) includes a plurality of K-band branching units (24) connected in a multi-level parallel configuration, wherein one end of the K-band microstrip branching unit (24) passing into the K-band waveguide structure (21) is a transition section (311) of the K-band branching end, and the other end is an output/input end (25) of the K-band branching unit for parallel connection.
  7. 3. A dual-band, dual-polarization planar antenna with a common aperture based on a waveguide structure of the “double cross” type according to claim 2, characterized in that a phase-shifting structure (312) is provided between the output/input ends (25) of the K-band branch block of two oppositely located microstrip branch blocks (24) of the K-band to compensate for the phase difference.
  8. 4. A dual-band, dual-polarization, common-aperture planar antenna based on a double-cross waveguide structure according to claim 3, characterized in that the phase-shifting structure (312) comprises two phase-shifting microstrip segments arranged parallel to each other with an interval and connected together at one end through an arc-shaped transition section, and the other ends of the phase-shifting microstrip segments are vertically connected to the output/input ends (25) of the K-band branch unit of two oppositely arranged K-band microstrip branch units (24), respectively.
  9. 5. A dual-band, dual-polarization, common-aperture planar antenna based on a "double-cross" waveguide structure according to any one of paragraphs 2-4, characterized in that the Ka-band microstrip line (310) is a proportionally reduced structure identical in shape to the K-band microstrip line (31), and in the direction of the vertical projection the Ka-band microstrip line (310) is located orthogonally relative to the K-band microstrip line (31).
  10. 6. A dual-band, dual-polarization, common-aperture planar antenna based on a double-cross waveguide structure according to claim 1, characterized in that the multi-level parallel network slot waveguide structure includes a plurality of waveguide transmitting paths (333) connected in a multi-level parallel configuration, wherein the edges of the waveguide transmitting paths (333) are surrounded by spaced-apart pins (332) with air gaps, and one end of the waveguide transmitting path (333) is provided with a metal step (334), and the other ends of each two waveguide transmitting paths (333) are connected for parallel connection, and the parallel connection is a subsequent parallel connection at the next level, and at the point of parallel connection of each level a power distribution pin (331) is provided.
  11. 7. A dual-band, dual-polarization, common-aperture planar antenna based on a double-cross waveguide structure according to claim 6, characterized in that the network slot waveguide structure is formed inside a metal cavity, and the upper cover of the metal cavity is provided with waveguide ports (335), and the positions of the waveguide ports (335) correspond to the positions of the metal steps (334), respectively, and are used for connection to the microstrip combining ends (314) of the K-band, respectively.
  12. 8. A dual-band, dual-polarization, common-aperture planar antenna based on a "double-cross" waveguide structure according to claim 1, characterized in that each branch end of the multi-level parallel power distribution network structure is connected to a vertical transition structure (321), which is connected upward to the Ka-band microstrip combining end.
  13. 9. A dual-band, dual-polarization, common-aperture planar antenna based on a double-cross waveguide structure according to claim 1, characterized in that either the radiating unit (17) with an open K-band waveguide or the radiating unit (18) with an open Ka-band waveguide includes a waveguide connection section and at least one level waveguide matching stage, which are arranged sequentially from bottom to top, wherein the vertical projection contour of the first level waveguide matching stage overlaps the vertical projection contour of the waveguide connection section, and the vertical projection contours of the waveguide matching stages gradually expand from level to level from bottom to top, wherein the waveguide connection section is used for connection to an airborne microstrip feeder network of the corresponding frequency range, and the waveguide matching stages are used for matching the waveguide with free space.
  14. 10. A dual-band, dual-polarization, common-aperture planar antenna based on a double-cross waveguide structure according to claim 1, characterized in that the radiating units (19) are arranged in the length direction and the width direction with a period P1 and a period P2, respectively, wherein the period P1 and the period P2 are unequal and correspond to the periods of the arrangement of the radiating units (17) with an open K-band waveguide and the radiating units (18) with an open Ka-band waveguide, respectively, and wherein the period P1 and the period P2 are positive integers, and both of them are less than the wavelength of the corresponding frequency range.

Description

Field of technology to which the invention relates The present application relates to dual-band, dual-polarized antenna technology, in particular to a dual-band, dual-polarized, common aperture planar antenna based on a double-cross waveguide structure. State of the art Dual-band, dual-polarized antennas are widely used in modern communication systems such as satellite communications and mobile communications, as they reduce the number of antennas and improve their noise immunity. A common method for creating dual-band dual polarization is to use a common radiating unit or radiating aperture for both the receive and transmit frequency bands, typically found in parabolic antennas and horn-waveguide arrays. However, these methods have inherent drawbacks, particularly evident in designs with mid- and high-frequency ratios, such as common aperture K/Ka configurations. Dual-band, dual-polarized parabolic antennas require complex dual-band feeds, and the field intensity at the edges of the feed aperture cannot simultaneously achieve optimal values for both the receive and transmit bands. This forces compromises in performance and typically results in low antenna radiation efficiency. Furthermore, dual-band, dual-polarized parabolic antennas have complex designs, high profiles, and large volumes, making them unsuitable for portable use. Horn-waveguide arrays, which utilize all-metal construction with low overall transmission loss, are well suited for dual-band, dual-polarization antennas. However, in the K/Ka bands, the spacing between horn-waveguide array elements is limited by matching and power distribution network layout, often preventing optimized performance in the high-frequency range. This results in large diffraction lobes in the high-frequency radiation pattern envelope, increasing energy dissipation during transmission and interfering with the use of other satellites. Thus, modern parabolic antennas and horn-waveguide arrays perform poorly in the K/Ka bands and suffer from design complexity, high profiles, low radiation efficiency, and large diffraction lobes in the Ka-band radiation pattern envelope. Notably, large diffraction lobes in the Ka-band radiation pattern envelope create significant interference to satellite communications and do not meet network access standards. Disclosure of invention Technical problem In order to overcome the shortcomings of the prior art, the present application proposes a dual-band, dual-polarization, common-aperture planar antenna based on a double-cross waveguide structure and solves problems such as the interdependent design of the transmit/receive bands in dual-band, dual-polarization, K/Ka planar antennas and the tendency to form significant diffraction lobes at high bands, thereby achieving an efficient common-aperture design in the K/Ka band with excellent radiation pattern envelope characteristics and ease of portability. Technical solution In order to achieve the above objectives, the following technical solution is used in the present invention: A dual-band, dual-polarized, common-aperture planar antenna based on a double-cross waveguide structure comprises, stacked from top to bottom, a radiating array, a first dielectric plate, a K-band metal back plate, a second dielectric plate, a Ka-band metal back plate, a Ka-band waveguide feeder network, and a K-band waveguide feeder network; The radiating array comprises a plurality of radiating units arranged in a rectangular array. Each radiating unit comprises one radiating unit with an open K-band waveguide and two orthogonal radiating units with an open Ka-band waveguide, forming two parallel transverse radiating structures; The first dielectric plate is provided with a plurality of K-band microstrip lines arranged in a rectangular array. Metal grooves on the lower surface of the radiating array and metal grooves on the upper surface of the K-band metal backplate form a plurality of first air microstrip cavities corresponding to the K-band microstrip lines. These first air microstrip cavities, together with the first dielectric plate and the K-band microstrip lines within the first air microstrip cavities, form an air microstrip K-band feeder network. The air microstrip K-band feeder network includes several first air microstrip waveguide units connected in a multi-level parallel configuration, which are matched and coupled to the radiating units. The first airborne microstrip waveguide unit contains one K-band waveguide structure and two upper orthogonal Ka-band waveguide structures, forming two parallel transverse waveguide structures. The transition section of the K-band branch end of the microstrip line is located within the K-band waveguide structure. The second dielectric plate is provided with a plurality of Ka-band microstrip lines arranged in a rectangular array, where two Ka-band microstrip lines form a pair corresponding to one K-band microstrip line. Metal grooves on the lower surface of the K-band me