A millimeter-wave radar phased array antenna

Abstract

The present invention discloses a millimeter-wave radar phased array antenna, belonging to the technical field of millimeter-wave radar antennas, comprising a transmitting antenna array and a receiving antenna array; the transmitting antenna array and the receiving antenna array are formed by an upper microstrip board with copper clad on both the upper and lower surfaces, a lower microstrip board with copper clad on both the upper and lower surfaces, and a plurality of metallized vias. The present invention adopts substrate-integrated waveguide feeding, which has the advantages of low loss, simple processing, and easy integration with active chips. The upper surface of the transmitting antenna radiation cavity contains a cross-shaped patch, which increases the range of the antenna array beam scanning and has a large-angle phase scanning capability under the appropriate unit spacing arrangement. The grounded coplanar waveguide back-feed is used, and when integrated with the active chip, the impact of the active chip on the antenna array radiation pattern is reduced, and it has high engineering application value.

Description

Technical Field

[0001] The present invention relates to the technical field of millimeter wave radar antennas, and in particular to a millimeter wave radar phased array antenna. Background Art

[0002] With the rapid development of automotive RF chips, automotive millimeter-wave radars are evolving into 4D imaging radars. 4D imaging radars not only output target distance, speed, and horizontal angle, but also target altitude information. This altitude information helps the radar distinguish between objects such as overpasses, manhole covers, pedestrians, and trucks. 4D imaging radars offer strong anti-interference capabilities, high resolution for angle, speed, and distance, and advanced target classification and tracking capabilities, making them highly effective in reducing traffic accidents and improving vehicle driving safety.

[0003] There has been much research on vehicle-mounted millimeter-wave radar antenna arrays. However, designing a millimeter-wave radar antenna with a simple structure, low processing requirements, and easy integration is very challenging. To this end, a millimeter-wave radar phased array antenna is proposed. Summary of the Invention

[0004] The technical problem to be solved by the present invention is how to design a millimeter-wave radar antenna with a simple structure, low processing requirements, and easy integration, and provides a millimeter-wave radar phased array antenna.

[0005] The present invention solves the above technical problems through the following technical solutions. The present invention includes a transmitting antenna array and a receiving antenna array; the transmitting antenna array and the receiving antenna array are formed by an upper microstrip board with copper clad on both the upper and lower surfaces, a lower microstrip board with copper clad on both the upper and lower surfaces, and a plurality of metallized vias;

[0006] The transmitting antenna array includes a plurality of transmitting antenna units arranged in parallel, each of which includes a first rectangular radiation cavity and a first substrate integrated waveguide feeding structure, wherein the first rectangular radiation cavity is arranged in the upper microstrip board, and the first substrate integrated waveguide feeding structure is arranged in the lower microstrip board, and the first rectangular radiation cavity is excited and fed; the receiving antenna array includes a plurality of receiving antenna units, each of which includes a second rectangular radiation cavity and a second substrate integrated waveguide feeding structure, wherein the second rectangular radiation cavity is arranged in the upper microstrip board, and the second substrate integrated waveguide feeding structure is arranged in the lower microstrip board, and the second rectangular radiation cavity is excited and fed;

[0007] A plurality of the first rectangular radiation cavities and a plurality of the second rectangular radiation cavities are arranged in a U-shaped array on the upper surface of the upper microstrip plate.

[0008] Furthermore, the first rectangular radiation cavity and the second rectangular radiation cavity both include a plurality of radiation cavity metallized vias, and the radiation cavity metallized vias are of two types, wherein the radiation cavity metallized vias on the long sides of the two rectangular radiation cavities are arranged through the upper microstrip board, and their upper and lower ends are connected to the upper and lower surfaces of the upper microstrip board with copper cladding; the radiation cavity metallized vias on the short sides of the two rectangular radiation cavities are arranged through the upper and lower microstrip boards, and their upper ends are connected to the upper surface of the upper microstrip board with copper cladding, and their lower ends are connected to the lower surface of the lower microstrip board with copper cladding; the rectangular openings of the first and second radiation cavities are located on the inner side of the radiation cavity metallized vias, and the corresponding positions on the upper and lower surfaces of the upper microstrip board are not copper clad.

[0009] Furthermore, a cross-shaped metal patch is provided at the center of the upper surface of the second rectangular radiation cavity of the receiving antenna unit.

[0010] Furthermore, the first substrate integrated waveguide feeding structure includes a first substrate integrated waveguide, a transversely biased radiation slot, and a first ground-coplanar waveguide feed line. The first substrate integrated waveguide is arranged in the lower microstrip board, the transversely biased radiation slot is arranged at one end of the first substrate integrated waveguide, and is located on the upper surface of the lower microstrip board. The first ground-coplanar waveguide feed line is arranged at the other end of the first substrate integrated waveguide, and is located on the lower surface of the lower microstrip board.

[0011] Furthermore, the transversely biased radiation slot is arranged parallel to the transmission direction of the first substrate integrated waveguide, and the transversely biased radiation slot is located at the center of the lower surface of the first rectangular radiation cavity.

[0012] Furthermore, the distance between the center of the transversely offset radiation slot and the short-circuit end of the first substrate integrated waveguide is 3 / 4 times λg, where λg is the transmission wavelength of the electromagnetic wave of the antenna working center frequency in the first substrate integrated waveguide.

[0013] Furthermore, the first grounded coplanar waveguide feed line is connected to a chip pin.

[0014] Furthermore, the second substrate integrated waveguide feeding structure includes a second substrate integrated waveguide, a longitudinal radiation slot, and a second ground coplanar waveguide feed line. The second substrate integrated waveguide is arranged in the lower microstrip board, the longitudinal radiation slot is arranged at one end of the second substrate integrated waveguide, and is located on the upper surface of the lower microstrip board. The second ground coplanar waveguide feed line is arranged at the other end of the second substrate integrated waveguide, and is located on the lower surface of the lower microstrip board.

[0015] Furthermore, the longitudinal radiation slot is arranged perpendicular to the transmission direction of the second substrate integrated waveguide, and the longitudinal radiation slot is located at the center of the lower surface of the second rectangular radiation cavity.

[0016] Furthermore, the distance between the center of the longitudinal radiation slot and the short-circuit end of the second substrate integrated waveguide is 1 / 4 times λg, where λg is the transmission wavelength of the electromagnetic wave of the antenna working center frequency in the second substrate integrated waveguide.

[0017] Furthermore, the first substrate integrated waveguide feeding structure is arranged horizontally, and the second substrate integrated waveguide feeding structure is arranged vertically.

[0018] Furthermore, the second grounded coplanar waveguide feed line is connected to a chip pin.

[0019] Furthermore, the area outside the copper-clad upper radiation cavity on the upper surface of the upper microstrip board is covered with a wave absorbing material layer having the same operating frequency as the antenna.

[0020] Compared with the existing technology, the present invention has the following advantages: the millimeter-wave radar phased array antenna adopts substrate integrated waveguide feeding, which has the advantages of low loss, simple processing, and easy integration with active chips; the upper surface of the transmitting antenna radiation component contains a cross-shaped patch, which increases the range of the antenna array beam scanning. Under the appropriate unit spacing arrangement, it has the ability of large-angle phase scanning within the vehicle-mounted radar frequency band; it adopts grounded coplanar waveguide back feeding, and when integrated with the active chip, it reduces the influence of the active chip on the antenna array radiation pattern, and has high engineering application value. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 1 is a schematic structural diagram of a millimeter wave radar phased array antenna according to an embodiment of the present invention;

[0022] Figure 2 (a) in the Figure 1 3D structural diagram of the receiving antenna unit;

[0023] Figure 2 (b) in the equation is Figure 1 A front view structural diagram of the receiving antenna unit;

[0024] Figure 2 (c) in the equation is Figure 1 A side view of the receiving antenna unit;

[0025] Figure 3 (a) in the sentence is Figure 1 3D structural diagram of the transmitting antenna unit;

[0026] Figure 3 (b) in the equation is Figure 1 A front view structural diagram of the transmitting antenna unit;

[0027] Figure 3 (c) in the equation is Figure 1 A side view of the transmitting antenna unit;

[0028] Figure 4 This is a copper cladding pattern of the receiving antenna unit on the upper surface of the first layer of microstrip board in the second embodiment of the present invention;

[0029] Figure 5 This is a copper cladding diagram of the receiving antenna unit on the lower surface of the first microstrip board in the second embodiment of the present invention;

[0030] Figure 6 This is a copper cladding pattern of the receiving antenna unit on the upper surface of the second layer of microstrip board in the second embodiment of the present invention;

[0031] Figure 7 This is a copper cladding diagram of the receiving antenna unit on the lower surface of the second microstrip board in the second embodiment of the present invention;

[0032] Figure 8 This is a copper cladding pattern of the transmitting antenna unit on the upper surface of the first layer of microstrip board in the second embodiment of the present invention;

[0033] Figure 9 This is a copper cladding diagram of the transmitting antenna unit on the lower surface of the first microstrip board in the second embodiment of the present invention;

[0034] Figure 10 This is a copper cladding pattern of the transmitting antenna unit on the upper surface of the second layer of microstrip board in the second embodiment of the present invention;

[0035] Figure 11 This is a copper cladding diagram of the transmitting antenna unit on the lower surface of the second microstrip board in the second embodiment of the present invention;

[0036] Figure 12 (a) is a schematic diagram of the active standing wave ratio of the receiving antenna array when scanning 0° in Example 2 of the present invention;

[0037] Figure 12 (b) is a schematic diagram of the active standing wave ratio of the receiving antenna array when scanning 15° in Example 2 of the present invention;

[0038] Figure 12 (c) is a schematic diagram of the active standing wave ratio of the receiving antenna array when scanning 30° in Example 2 of the present invention;

[0039] Figure 12 (d) is a schematic diagram of the active standing wave ratio of the receiving antenna array when scanning 45° in Example 2 of the present invention;

[0040] Figure 12 (e) is a schematic diagram of the active standing wave ratio of the receiving antenna array when scanning 60° in Example 2 of the present invention;

[0041] Figure 13 (a) is a schematic diagram of the active standing wave ratio of the transmitting antenna array when scanning 0° in Example 2 of the present invention;

[0042] Figure 13 (b) is a schematic diagram of the active standing wave ratio of the transmitting antenna array when scanning 15° in Example 2 of the present invention;

[0043] Figure 13 (c) is a schematic diagram of the active standing wave ratio of the transmitting antenna array when scanning 30° in Example 2 of the present invention;

[0044] Figure 14 (a) is a gain diagram of the receiving antenna array scanning at different angles at 75 GHz in the second embodiment of the present invention;

[0045] Figure 14 (b) is a gain diagram of the receiving antenna array scanning at different angles at 78 GHz in the second embodiment of the present invention;

[0046] Figure 14 (c) is a gain diagram of the receiving antenna array scanning at different angles at 81 GHz in the second embodiment of the present invention;

[0047] Figure 15 (a) is a gain diagram of the transmitting antenna array scanning at different angles at 75 GHz in the second embodiment of the present invention;

[0048] Figure 15 (b) is a gain diagram of the transmitting antenna array scanning at different angles at 78 GHz in the second embodiment of the present invention;

[0049] Figure 15 (c) is a gain diagram of the transmitting antenna array scanning at different angles at 81 GHz in the second embodiment of the present invention.

[0050] In the figure: 1-receiving antenna unit; 2-transmitting antenna unit; 3-absorbing material layer; 4-rectangular radiation cavity of receiving antenna unit; 5-rectangular radiation cavity of transmitting antenna unit; 6-receiving antenna SIW feed line; 7-transmitting antenna SIW feed line; 8-cross-shaped metal patch; 9-first circular metalized via; 10-longitudinal radiation slot; 11-second circular metalized via; 12-third circular metalized via; 13-rectangular opening of the rectangular radiation cavity of transmitting antenna unit; 14-bias radiation slot. DETAILED DESCRIPTION

[0051] The following is a detailed description of an embodiment of the present invention. This embodiment is implemented based on the technical solution of the present invention, and provides a detailed implementation method and specific operation process. However, the protection scope of the present invention is not limited to the following embodiment.

[0052] This embodiment provides a technical solution: a millimeter-wave radar phased array antenna, including two columns of transmitting antenna arrays and two rows of receiving antenna arrays, both of which are phased array antennas, the transmitting antenna array beam has a phased scanning capability in pitch direction, and the receiving antenna array beam has a phased scanning capability in azimuth direction.

[0053] like Figure 1 As shown, in this embodiment, the transmit antenna array and receive antenna array utilize the same two-layer printed circuit board (PCB) design. The rectangular radiating cavities 5 and 4 of the transmit antenna units are located on the first PCB layer. A substrate-integrated waveguide (SIW) with radiating slots is located on the second PCB layer, providing excitation and feed to the rectangular radiating cavities on the first layer. The ends of the transmit antenna SIW feed lines 7 and the receive antenna SIW feed lines 6 are converted to ground coplanar waveguide (GCPW) feed lines to facilitate interconnection with chip pins.

[0054] In this embodiment, the millimeter-wave radar phased array antenna adopts a "mouth"-shaped array, with the transmitting antenna being two vertical rows of linear arrays and the receiving antenna being two parallel rows of linear arrays. The spacing between the transmitting antenna unit 2 and the receiving antenna unit 1 must satisfy the constraint relationship between the phased array scanning angle and the antenna unit spacing. , d is the antenna unit spacing, λ is the antenna operating wavelength, θ is the scanning angle.

[0055] In this embodiment, the radiation cavities of several transmitting antenna elements and several receiving antenna elements form a "mouth" shape. The positional relationship between the transmitting and receiving antenna arrays is adjusted and optimized to ensure that the grating lobes of the transmitting antenna pattern coincide with the null point of the receiving antenna pattern. This suppresses the high sidelobes produced by the combined radiation pattern of the transmitting and receiving antennas. This "mouth" arrangement achieves a narrow composite beam with a reduced number of antenna elements, improving the resolution of millimeter-wave phased array radars.

[0056] In this embodiment, the upper surface of the first layer PCB, outside the radiation cavity, is covered with a wave absorbing material layer 3 having the same operating frequency as the antenna.

[0057] In this embodiment, a transverse radiation slot is etched on the transmitting antenna SIW feed line 7 (arranged parallel to the transmission direction of the substrate integrated waveguide), and the center of the transverse radiation slot is 1 / 4 λg away from the short-circuit end of the substrate integrated waveguide, where λg is the transmission wavelength of the electromagnetic wave at the antenna operating center frequency in the SIW.

[0058] In this embodiment, the rectangular radiation cavity 5 of the transmitting antenna unit includes a plurality of first radiation cavity metallized vias. There are two types of first radiation cavity metallized vias, namely, longer first radiation cavity metallized vias 91 (the number is 6, 3 in each group, constituting the short side) and shorter first radiation cavity metallized vias (the number is 4, 2 in each group, constituting the short side), see Figure 3 In (a), the plated holes on the long sides of the rectangular radiating cavity (the longer first radiating cavity plated via 91) extend through the upper microstrip board, while the plated holes on the short sides of the rectangular radiating cavity (the shorter first radiating cavity plated via 92) extend through both the upper and lower microstrip boards. The upper and lower ends of the plated holes are copper-clad to the upper and lower surfaces of the microstrip boards. The opening of the rectangular radiating cavity 5 of the transmitting antenna unit is located inside the first radiating cavity plated via, and its upper and lower surfaces are not copper-clad.

[0059] In this embodiment, the transverse radiation slot on the transmitting antenna SIW feed line 7 is a horizontally offset radiation slot, and the transverse radiation slot is located at the center of the lower surface of the rectangular radiation cavity. The center of the radiation slot is 3 / 4 times λg away from the short-circuit end of the substrate integrated waveguide, where λg is the transmission wavelength of the electromagnetic wave at the antenna working center frequency in the SIW.

[0060] In this embodiment, the rectangular radiation cavity 4 of the receiving antenna unit includes a plurality of second radiation cavity metallized vias. There are two types of metallized vias, namely, longer second radiation cavity metallized vias (the number is 6, 3 in each group, forming two short sides) and shorter second radiation cavity metallized vias (the number is 6, 2 in each group, forming two short sides), see Figure 4 In (a), the plated holes on the long sides of the rectangular radiating cavity (the longer plated vias in the second radiating cavity) extend through the upper microstrip board, while the plated holes on the short sides of the rectangular radiating cavity (the shorter plated vias in the second radiating cavity) extend through both the upper and lower microstrip boards. Copper clad the upper and lower ends of the plated holes and connect them to the upper and lower surfaces of the microstrip boards. The opening of the rectangular radiating cavity 4 of the transmitting antenna unit is located inside the plated vias in the second radiating cavity, and its upper and lower surfaces are not covered with copper. The long and short sides of the rectangular radiating cavity 4 of the transmitting antenna unit correspond to the long and short sides of the rectangular radiating cavity 5 of the transmitting antenna unit.

[0061] In this embodiment, a cross-shaped metal patch is provided at the center of the upper surface of the rectangular radiation cavity 4 of the receiving antenna unit.

[0062] In this embodiment, a longitudinal radiation slot is etched on the SIW feed line 6 of the receiving antenna (set perpendicular to the substrate integrated waveguide transmission direction). The longitudinal radiation slot is a horizontal radiation slot located at the center of the lower surface of the rectangular radiation cavity 4 of the receiving antenna unit.

[0063] The distance between the center of the longitudinal radiation slot and the short-circuit end of the substrate integrated waveguide is 1 / 4 times λg, where λg is the transmission wavelength of the electromagnetic wave at the antenna working center frequency in the substrate integrated waveguide.

[0064] In this embodiment, the transmitting antenna SIW feeder 7 is arranged horizontally, and the receiving antenna SIW feeder 6 is arranged vertically.

[0065] In this embodiment, the metallized vias constituting the radiation cavity and the substrate integrated waveguide are distributed as densely as possible. Example 2

[0066] This embodiment provides a millimeter-wave radar antenna array operating at 75-81 GHz as an example. It includes two layers of Rogers 3003 microstrip boards. From top to bottom, the first layer is 0.508 mm thick, and the second layer is 0.254 mm thick. The first layer is clad on both sides with a thickness of 17.5 μm; the second layer is clad on both sides with a thickness of 17.5 μm. The two microstrip boards are bonded with a 0.1 mm thick prepreg. Figure 1 As shown, the antenna array contains 2 columns of transmitting antennas, each column contains 8 transmitting antenna units. The antenna array contains 2 rows of receiving antennas, each row contains 16 transmitting antenna units. The transmitting antenna units and receiving antenna units each correspond to 4 copper clad layers. The first layer has a copper clad thickness of 17.5um on the upper surface and no copper clad on the lower surface; the second layer has a copper clad thickness of 17.5um on both sides. Looking from top to bottom, the copper clad pattern of each layer is as follows: Figure 4-11 As shown, the shaded part is the copper clad area.

[0067] Figure 4-11 The antenna array size parameters are given in mm.

[0068] The millimeter-wave radar antenna array used in the implementation case has the capability of phase scanning. The transmitting antenna array can achieve ±60° beam scanning, and the receiving antenna array can achieve ±30° beam scanning. After simulation calculation, the standing wave and gain diagram of the antenna array are as follows: Figure 12-15 As shown in the figure, within the 75 GHz to 81 GHz range, the SWR of the transmitting antenna array is less than 2 when scanning within a 45° range, and less than 3 when scanning within a 60° range. The SWR of the receiving antenna array is less than 2 when scanning within a ±30° range. Both the transmitting and receiving antenna arrays meet the phase scanning spacing requirements, and no grating lobes appear in the radiation patterns.

[0069] In summary, the millimeter-wave radar phased array antenna of the above embodiment adopts substrate-integrated waveguide feeding, which has the advantages of low loss, simple processing, and easy integration with active chips; the upper surface of the transmitting antenna radiation component contains a cross-shaped patch, which improves the range of the antenna array beam scanning. Under the appropriate unit spacing arrangement, it has a large-angle phase scanning capability within the vehicle-mounted radar frequency band; the use of grounded coplanar waveguide back-feeding, when integrated with the active chip, reduces the impact of the active chip on the antenna array radiation pattern, and has high engineering application value.

[0070] Although the embodiments of the present invention have been shown and described above, it will be understood that the above embodiments are illustrative and are not to be construed as limitations on the present invention. A person skilled in the art may change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A millimeter wave radar phased array antenna, characterized in that: include: Transmitting antenna array, receiving antenna array; The transmitting antenna array and the receiving antenna array are formed by an upper microstrip board with copper clad on both the upper and lower surfaces, a lower microstrip board with copper clad on both the upper and lower surfaces, and a plurality of metallized vias; The transmitting antenna array includes a plurality of transmitting antenna units arranged in parallel, each of which includes a first rectangular radiation cavity and a first substrate integrated waveguide feeding structure, wherein the first rectangular radiation cavity is arranged in the upper microstrip board, and the first substrate integrated waveguide feeding structure is arranged in the lower microstrip board to excite and feed the first rectangular radiation cavity; The receiving antenna array includes a plurality of receiving antenna units, each of which includes a second rectangular radiation cavity and a second substrate integrated waveguide feeding structure, wherein the second rectangular radiation cavity is arranged in the upper microstrip board, and the second substrate integrated waveguide feeding structure is arranged in the lower microstrip board to excite and feed the second rectangular radiation cavity; The first rectangular radiation cavities of the plurality of transmitting antenna units and the second rectangular radiation cavities of the plurality of receiving antenna units are arranged in a U-shaped pattern on the upper surface of the upper microstrip board; The first rectangular radiation cavity and the second rectangular radiation cavity each include a plurality of radiation cavity metallized vias. The radiation cavity metallized vias are of two types: the radiation cavity metallized vias on the long sides of the two rectangular radiation cavities penetrate the upper microstrip board, and their upper and lower ends are connected to the copper clad upper and lower surfaces of the upper microstrip board; the radiation cavity metallized vias on the short sides of the two rectangular radiation cavities penetrate the upper and lower microstrip boards, and their upper ends are connected to the copper clad upper surface of the upper microstrip board, and their lower ends are connected to the copper clad lower surface of the lower microstrip board; The rectangular openings of the first and second rectangular radiation cavities are located inside the metallized via holes of the radiation cavities, and the upper and lower surfaces of the upper microstrip board corresponding to the rectangular openings of the first and second rectangular radiation cavities are not covered with copper.

2. The millimeter wave radar phased array antenna according to claim 1, characterized in that: A cross-shaped metal patch is provided at the center of the upper surface of the second rectangular radiation cavity of the receiving antenna unit.

3. The millimeter wave radar phased array antenna according to claim 2, characterized in that: The first substrate integrated waveguide feeding structure includes a first substrate integrated waveguide, a transversely biased radiation slot, and a first ground coplanar waveguide feed line. The first substrate integrated waveguide is arranged in the lower microstrip board, the transversely biased radiation slot is arranged at one end of the first substrate integrated waveguide, and is located on the upper surface of the lower microstrip board. The first ground coplanar waveguide feed line is arranged at the other end of the first substrate integrated waveguide, and is located on the lower surface of the lower microstrip board.

4. The millimeter wave radar phased array antenna according to claim 3, characterized in that: The first substrate integrated waveguide transversely offset radiation slot is arranged parallel to the transmission direction of the first substrate integrated waveguide, and the transversely offset radiation slot is located at the center of the lower surface of the first rectangular radiation cavity.

5. The millimeter wave radar phased array antenna according to claim 4, characterized in that: The distance between the center of the transversely offset radiation slot and the short-circuit end of the first substrate integrated waveguide is 3 / 4 times λg, where λg is the transmission wavelength of the electromagnetic wave at the antenna's working center frequency in the first substrate integrated waveguide.

6. The millimeter wave radar phased array antenna according to claim 5, characterized in that: The second substrate integrated waveguide feeding structure includes a second substrate integrated waveguide, a longitudinal radiation slot, and a second ground coplanar waveguide feed line. The second substrate integrated waveguide is arranged in the lower microstrip board. The longitudinal radiation slot is arranged at one end of the second substrate integrated waveguide and is located on the upper surface of the lower microstrip board. The second ground coplanar waveguide feed line is arranged at the other end of the second substrate integrated waveguide and is located on the lower surface of the lower microstrip board.

7. The millimeter wave radar phased array antenna according to claim 6, characterized in that: The longitudinal radiation slot is arranged perpendicular to the transmission direction of the second substrate integrated waveguide, and the longitudinal radiation slot is located at the center of the lower surface of the second rectangular radiation cavity.

8. The millimeter wave radar phased array antenna according to claim 7, characterized in that: The distance between the center of the longitudinal radiation slot and the short-circuit end of the second substrate integrated waveguide is 1 / 4 times λg, where λg is the transmission wavelength of the electromagnetic wave of the antenna working center frequency in the second substrate integrated waveguide.

9. The millimeter wave radar phased array antenna according to claim 8, characterized in that: The areas outside the rectangular radiation cavity on the upper surface of the upper microstrip plate are all covered with a wave absorbing material layer having the same operating frequency as the antenna.

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