A dual-polarized millimeter-wave on-chip antenna

Abstract

This invention discloses a dual-polarized millimeter-wave on-chip antenna, comprising, from bottom to top, a metal ground layer, a silicon substrate layer, and a metal on-chip antenna layer. The metal on-chip antenna layer includes a metal ground coplanar layer, a metal plate layer, a metal center patch, a first ground coplanar waveguide transmission line, a second ground coplanar waveguide transmission line, a third ground coplanar waveguide transmission line, and a coupled microstrip balun. Both the metal ground coplanar layer and the metal plate layer have a central cutout. The metal center patch is located at the central cutout of the metal plate layer, and a gap exists between the metal center patch and the central cutout. This invention offers high gain and can achieve interference self-suppression.

Description

Technical Field

[0001] This invention relates to antennas, and more particularly to a dual-polarized millimeter-wave on-chip antenna. Background Technology

[0002] The rapid development of the semiconductor industry over the past two decades has led to significant technological innovations in transistors, integrated circuits, and chip manufacturing processes. The rapid growth of wireless communication has created diverse demands for integrated circuit systems, making high-performance, miniaturized analog-to-digital circuits and radio frequency (RF) systems particularly important. In current wireless system research, system-on-a-chip (SoC) has become a hot research area. SoC integrates all modules of a wireless system onto a single chip, including a digital microprocessor core, analog mixed-signal circuitry, RF front-end, and antenna. Compared to traditional multi-chip module integration methods and packaged systems, SoC offers many advantages, such as reduced external interconnect interference and reduced manufacturing complexity.

[0003] As a module for receiving and transmitting signals in a wireless system, the antenna is an essential component of a system-on-a-chip (SoC). An antenna integrated on a chip is called an on-chip antenna. On-chip antennas have many advantages over board-level antennas: (1) On-chip antennas are generally implemented through the thickest top layer of metal in the process, and are connected to the RF front-end circuit through vertical metal interlayer vias. They do not require external interconnects to connect to the circuit, reducing manufacturing difficulty and cost. At the same time, they eliminate parasitic losses from external interconnects, which is beneficial to improving system bandwidth. (2) On-chip antennas are designed in the same way as RF circuits, and can achieve conjugate matching with the RF front-end, reducing circuit complexity and shortening the wireless system design cycle. However, there are also many obstacles in the design of on-chip antennas. For example, the mainstream chip process used for on-chip antennas is CMOS process, and most CMOS processes use silicon substrates with high dielectric constant and low resistivity. This material has a low cost and is suitable for the design of RF front-end circuits. However, in the design of on-chip antennas, the distance between the metal layer used in the antenna and the substrate is very small. The low impedance and high dielectric constant of the silicon substrate cause most of the energy radiated by the antenna to be concentrated downwards. Therefore, the gain of existing on-chip antennas is generally low, which is also the main direction and hot spot of current research on on-chip antennas.

[0004] With the widespread development of wireless communication services, microwave spectrum resources are becoming increasingly scarce, and various forms of interference between communication systems are also increasing. To resolve the contradiction between the ever-growing demand for wireless communication applications and the ever-increasing demand for spectrum resources, researchers are searching for an optimal method to effectively utilize spectrum resources. Full-duplex technology allows for simultaneous transmission and reception of signals using the same carrier frequency, doubling the utilization rate of wireless spectrum resources compared to existing full-duplex communication methods. However, full-duplex transmitters may generate strong interference signal leakage to receivers; therefore, effectively suppressing self-interference is a key factor in whether full-duplex can significantly improve frequency utilization. Summary of the Invention

[0005] Purpose of the invention: This invention addresses the problems existing in the prior art by providing a dual-polarized millimeter-wave on-chip antenna that can suppress self-interference and has higher gain.

[0006] Technical Solution: The dual-polarized millimeter-wave on-chip antenna of the present invention includes a metal ground layer, a silicon substrate layer, and a metal on-chip antenna layer stacked sequentially from bottom to top. The metal on-chip antenna layer includes a metal ground coplanar layer, a metal plate layer, a metal center patch, a first ground coplanar waveguide transmission line, a second ground coplanar waveguide transmission line, a third ground coplanar waveguide transmission line, and a coupled microstrip balun. The metal ground coplanar layer and the metal plate layer share a common center, and both have a central cutout. The metal ground coplanar layer is stacked on the silicon substrate layer, and the metal plate layer is stacked on the metal ground coplanar layer. The metal center patch is located at the central cutout of the metal plate layer. A gap is provided between the metal plate layer and the metal plate layer. One end of the first grounded coplanar waveguide transmission line is connected to the metal center patch, and the other end serves as the antenna transmitting port. One end of the second grounded coplanar waveguide transmission line is connected to the metal center patch, and the other end is connected to the first input terminal of the coupled microstrip line balun. One end of the third grounded coplanar waveguide transmission line is connected to the metal center patch, and the other end is connected to the second input terminal of the coupled microstrip line balun. The first output terminal and the second output terminal of the coupled microstrip line balun serve as the first receiving port and the second receiving port of the antenna, respectively. The first receiving port and the second receiving port of the antenna are arranged adjacent to each other and are both located on the opposite side of the antenna transmitting port.

[0007] Furthermore, the antenna layer on the metal sheet also includes a metal isolation wall, which surrounds the periphery of the metal plate layer and is connected to the metal plate layer at the first receiving port, the second receiving port, and the transmitting port of the antenna, respectively.

[0008] Furthermore, the metal plate layer is also provided with a first cutout, a second cutout, a third cutout, and a fourth cutout. The first cutout matches the shape of the first grounded coplanar waveguide transmission line and is used to place the first grounded coplanar waveguide transmission line. The second cutout matches the shape of the second grounded coplanar waveguide transmission line and is used to place the second grounded coplanar waveguide transmission line. The third cutout matches the shape of the third grounded coplanar waveguide transmission line and is used to place the third grounded coplanar waveguide transmission line. The fourth cutout matches the shape of the coupled microstrip line balun and is used to place the coupled microstrip line balun. Moreover, there is a gap between the first grounded coplanar waveguide transmission line, the second grounded coplanar waveguide transmission line, the third grounded coplanar waveguide transmission line, and the coupled microstrip line balun and the metal plate layer.

[0009] Furthermore, the outer perimeter of the metal plate is square, and the inner perimeter is an octagonal hollow center. The gap is octagonal, and its perimeter is one antenna medium wavelength.

[0010] Furthermore, the metal center patch is octagonal, with the first horizontal side facing the antenna transmitting port connected to the first grounded coplanar waveguide transmission line, and the two vertical sides located on the first horizontal side connected to the second grounded coplanar waveguide transmission line and the third grounded coplanar waveguide transmission line, respectively.

[0011] Furthermore, a first hollow groove is formed at the connection point between the metal center patch and the first grounded coplanar waveguide transmission line, a second hollow groove is formed at the connection point between the metal center patch and the second grounded coplanar waveguide transmission line, a third hollow groove is formed at the connection point between the metal center patch and the third grounded coplanar waveguide transmission line, and a fourth hollow groove is formed on the metal center patch opposite to the first hollow groove. The first, second, third, and fourth hollow grooves are all meander patterns.

[0012] Furthermore, the coupled microstrip balun includes a straight microstrip line, a first L-shaped microstrip line, and a second L-shaped microstrip line. The straight microstrip line, the first L-shaped microstrip line, and the second L-shaped microstrip line form an inverted T-shaped structure. The two ends of the straight microstrip line are respectively connected to a second grounded coplanar waveguide transmission line and a third grounded coplanar waveguide transmission line. One end of the first L-shaped microstrip line is connected to the metal grounded coplanar layer through a metal via, and the other end serves as the first output terminal of the coupled microstrip balun. One end of the second L-shaped microstrip line is connected to the metal grounded coplanar layer through a metal via, and the other end serves as the second output terminal of the coupled microstrip balun.

[0013] Furthermore, the outer layer of the metal grounding coplanar layer is a square ring, and the inner layer is a square. The outer square ring and the inner square are connected at the antenna transmitting port, the first antenna receiving port, and the second antenna receiving port. The outer square ring is located below the metal isolation wall. The inner square has periodically arranged grids directly below the first grounding coplanar waveguide transmission line, the second grounding coplanar waveguide transmission line, the third grounding coplanar waveguide transmission line, and the coupled microstrip balun.

[0014] Furthermore, the metal plate layer is composed of several stacked metal layers, and the metal center patch has the same thickness and is coplanar with the topmost metal layer of the metal plate layer.

[0015] Furthermore, the metal partition wall is composed of several stacked metal layers, and the thickness is the same as the thickness of the metal plate layer.

[0016] Compared with the prior art, the beneficial effects of this invention are: 1) The main parts of the antenna structure of this invention (metal center patch and grounded coplanar waveguide transmission line) are far away from the silicon substrate, which can reduce the current loop loss and surface wave loss formed between the antenna and the silicon substrate layer, and improve the performance of the antenna. 2) The bottom metal grounding layer can improve the gain and efficiency of the energy radiated downward by the reflective antenna, and achieve the advantages of low profile and high gain of on-chip antennas; 3) The polarizations of the receiving and transmitting antennas of this invention are mutually orthogonal. The receiving antenna naturally integrates a coupled microstrip balun structure on the basis of constructing a differential branch to cancel the self-interference signal leaked by the transmitting antenna, realizing deep-level cancellation technology at the antenna end, which has the advantage of high isolation. 4) This invention integrates the receiving and transmitting antennas into a single design, resulting in a compact overall structure. It also achieves on-chip integration with the RF front-end chip, eliminating parasitic losses from external interconnects, improving system bandwidth, and realizing antenna miniaturization and system integration. Attached Figure Description

[0017] Figure 1 A stack-up diagram of a dual-polarized millimeter-wave on-chip antenna provided in an embodiment of the present invention; Figure 2 This is a schematic diagram of the structure of a dual-polarized millimeter-wave on-chip antenna provided in an embodiment of the present invention; Figure 3 This is an exploded structural diagram of a dual-polarized millimeter-wave on-chip antenna provided in an embodiment of the present invention; Figure 4 This is a schematic diagram illustrating the principle of coupling microstrip line baluns in an embodiment of the present invention; Figure 5 The figure shows the simulation results of return loss in an embodiment of the present invention. Figure 6This is a simulation result diagram of the isolation degree in an embodiment of the present invention; Figure 7 This is a simulation curve of the gain and efficiency of the transmitting antenna in an embodiment of the present invention; Figure 8 This is a simulation curve of the gain and efficiency of the receiving antenna in an embodiment of the present invention; Figure 9 This is the far-field radiation pattern of the transmitting antenna at 140 GHz according to an embodiment of the present invention; Figure 10 This is the far-field radiation pattern of the receiving antenna at 140 GHz in an embodiment of the present invention. Detailed Implementation

[0018] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] This invention provides a dual-polarized millimeter-wave on-chip antenna with an overall size of 0.55mm × 0.57mm; specifically, it employs a 40nm CMOS process, such as... Figure 1 As shown, the antenna consists of a metal ground layer 1 (to improve gain and efficiency), a silicon substrate layer 2, and a metal-on-sheet antenna layer 3, stacked sequentially from bottom to top. The metal ground layer 1 reflects the energy radiated downwards by the antenna. The silicon substrate layer 2 has a resistivity of 10 Ω·cm and a relative permittivity of 11.9. A special silicon-shaving process is used to thin the silicon substrate to 100 μm, approximately one-quarter of the wavelength of the dielectric medium at the antenna's center frequency. The metal-on-sheet antenna layer 3 is the main structural component of the antenna and employs a symmetrical design.

[0020] like Figure 2 , 3As shown, the antenna layer 3 on the metal sheet includes a metal ground coplanar layer 4, a metal plate layer 5, a metal center patch 6, a first ground coplanar waveguide transmission line 7, a second ground coplanar waveguide transmission line 8, a third ground coplanar waveguide transmission line 9, and a coupled microstrip balun 10. The metal ground coplanar layer 4 and the metal plate layer 5 share a common center, and both have a central cutout. The metal ground coplanar layer 4 is stacked on the silicon substrate layer 2, and the metal plate layer 5 is stacked on the metal ground coplanar layer 4. The metal center patch 6 is located at the central cutout of the metal plate layer 5, and a gap 11 is provided between it and the metal plate layer 5. The first grounded coplanar waveguide transmission line 7 is connected at one end to the metal center patch 6, and the other end serves as the antenna transmitting port P1. The second grounded coplanar waveguide transmission line 8 is connected at one end to the metal center patch 6, and the other end serves as the first input terminal P4 of the coupled microstrip balun 10. The third grounded coplanar waveguide transmission line 9 is connected at one end to the metal center patch 6, and the other end serves as the second input terminal P5 of the coupled microstrip balun 10. The first output terminal P2 and the second output terminal P3 of the coupled microstrip balun 10 serve as the first and second receiving ports of the antenna, respectively. The first and second receiving ports are adjacent to each other and are located opposite the antenna transmitting port P1. Both the transmitting and receiving ends of the antenna are fed by grounded coplanar waveguide transmission lines 7, 8, and 9.

[0021] In specific implementation, the outer perimeter of the metal plate layer 5 is square, and the inner perimeter is an octagonal central hollow. The metal plate layer 5 is also provided with a first hollow 51, a second hollow 52, ​​a third hollow 53, and a fourth hollow 54. The first hollow 51 matches the shape of the first grounded coplanar waveguide transmission line 7 and is used to place the first grounded coplanar waveguide transmission line 7. The second hollow 52 matches the shape of the second grounded coplanar waveguide transmission line 8 and is used to place the second grounded coplanar waveguide transmission line 8. The third hollow 53 matches the shape of the third grounded coplanar waveguide transmission line 9 and is used to place the third grounded coplanar waveguide transmission line 9. The fourth hollow 54 matches the shape of the coupled microstrip line balun 10 and is used to place the coupled microstrip line balun 10. Furthermore, there is a gap between the first grounded coplanar waveguide transmission line 7, the second grounded coplanar waveguide transmission line 8, the third grounded coplanar waveguide transmission line 9, and the coupled microstrip line balun 10 and the metal plate layer 5.

[0022] In order to isolate the surface waves generated by the antenna radiation from the radio frequency front-end circuit and eliminate the influence of the antenna on the circuit, a metal isolation wall 12 is also provided on the antenna layer 3 on the metal sheet. The metal isolation wall 12 is arranged around the periphery of the metal plate layer 5 and is connected to the metal plate layer 5 at the first receiving port, the second receiving port, and the transmitting port of the antenna, respectively. The metal isolation wall 12 is composed of several layers of metal stacked together, and the thickness is the same as the thickness of the metal plate layer 5.

[0023] In specific implementation, the slot 11 is octagonal, with a perimeter equal to one antenna dielectric wavelength. The corresponding metal center patch 6 is also octagonal. The first horizontal side facing the antenna transmitting port is connected to the first grounded coplanar waveguide transmission line 7, and the two vertical sides located on the first horizontal side are connected to the second grounded coplanar waveguide transmission line 8 and the third grounded coplanar waveguide transmission line 9, respectively. A first slot 61 is formed at the connection point between the metal center patch 6 and the first grounded coplanar waveguide transmission line 7, a second slot 62 is formed at the connection point between the metal center patch 6 and the second grounded coplanar waveguide transmission line 8, and a third slot 63 is formed at the connection point between the metal center patch 6 and the third grounded coplanar waveguide transmission line 9. A fourth slot 64 is formed on the metal center patch 6 opposite to the first slot 61 to achieve symmetry. The first slot 61, the second slot 62, the third slot 63, and the fourth slot 64 are all meander patterns used for impedance matching. The size and shape of the four hollow slots may not be the same, but the first hollow slot 61 and the third hollow slot 63 are the same, and the second hollow slot 62 and the fourth hollow slot 64 are the same.

[0024] In practical implementation, the outer layer of the metal grounding coplanar layer 4 is a square ring, and the inner layer is a square. The outer square ring and the inner square are connected at the antenna transmitting port P1, the first antenna receiving port P2, and the second antenna receiving port P3. The outer square ring is located below the metal isolation wall 12 and serves the same purpose as the metal isolation wall 12 for isolation. The inner square has periodically arranged gratings 13 directly below the first grounding coplanar waveguide transmission line 7, the second grounding coplanar waveguide transmission line 8, the third grounding coplanar waveguide transmission line 9, and the coupled microstrip balun 10. The gratings 13 can change the effective dielectric constant, thereby reducing the phase velocity of the electromagnetic waves on the transmission line to varying degrees to achieve a slow-wave effect and achieve antenna miniaturization. Changing the width and spacing of the gratings can adjust the effective dielectric constant.

[0025] In practice, metal plate 5 can be composed of 11 stacked metal layers. The metal center patch 6 has the same thickness as the top metal layer of metal plate 5 and is coplanar, meaning the metal center patch 6 is located on the top layer. The first ground coplanar waveguide transmission line 7, the second ground coplanar waveguide transmission line 8, and the third ground coplanar waveguide transmission line 9 are also located on the top layer. The coupling microstrip balun 10 is located on the layer below the top layer, and the metal ground coplanar layer 4 is located on the bottom layer. The top metal layer is wrapped with a passivation layer composed of silicon nitride and silicon dioxide derivatives to isolate it from external environmental influences and prevent oxidation of the top metal layer.

[0026] In specific implementation, the coupled microstrip balun 10 includes a straight microstrip line 101, a first L-shaped microstrip line 102, and a second L-shaped microstrip line 103. The straight microstrip line 101, the first L-shaped microstrip line 102, and the second L-shaped microstrip line 103 form an inverted T-shaped structure. The two ends of the straight microstrip line 101 serve as the first input terminal P4 and the second input terminal P5, respectively connected to the first grounded coplanar waveguide transmission line 7 and the second grounded coplanar waveguide transmission line 8, specifically through vertical interconnection via metal vias. One end P6 of the first L-shaped microstrip line 102 is connected to the metal grounded coplanar layer 4 through a metal via, and the other end serves as the first output terminal P2 of the coupled microstrip balun 10. One end of the second L-shaped microstrip line is connected to the metal grounded coplanar layer 4 through a metal via, and the other end serves as the second output terminal P3 of the coupled microstrip balun 10. The coupled microstrip balun 10 feeds the differential-mode signal received by the antenna into the RF front-end receiving circuit, suppressing the common-mode signal leaked from the transmitting antenna and improving antenna isolation.

[0027] Figure 4 This is a schematic diagram of a coupled microstrip balun. P4 and P5 are the input terminals of the coupled microstrip balun; P2 and P3 are the output terminals. The differential-mode signal received by the antenna is fed into the input ports P4 and P5, and then coupled out to ports P2 and P3 via the microstrip line. Meanwhile, the common-mode interference signal leaking from the antenna transmit port P1 to the receiver is suppressed by the coupled microstrip balun after passing through ports P4 and P5.

[0028] Figure 5 The simulation results show the relationship between return loss of the transmitting and receiving antennas and frequency. When the return loss is greater than 10dB, the frequency range covered by the transmitting antenna is 134.3GHz~145.6GHz, and the frequency range covered by the receiving antenna is 133.4GHz~147.2GHz.

[0029] Figure 6 Simulation results show the relationship between isolation and frequency between transmit and receive antenna ports. In the entire D-band (110GHz~170GHz), the isolation between ports is greater than 68dB, achieving a high level of isolation that can be applied to full-duplex communication systems.

[0030] Figure 7 and Figure 8 Simulation results of the gain and radiation efficiency of the on-chip transmit and receive antennas as a function of frequency are shown. As shown in the figure, the gain and radiation efficiency of the transmit antenna at 140 GHz are -4.1 dBi and 8.1%, respectively; the gain and radiation efficiency of the receive antenna at 140 GHz are -4.0 dBi and 10%, respectively; both transmit and receive antennas maintain relatively stable gain and radiation efficiency within the operating frequency band.

[0031] Figure 9 and Figure 10 The far-field radiation patterns of the on-chip transmitting and receiving antennas at 140 GHz are shown respectively. Both the transmitting and receiving antennas show high polarization purity and excellent cross-polarization ratio.

Claims

1. A dual-polarized millimeter-wave on-chip antenna, characterized by: The device comprises, from bottom to top, a metal ground layer, a silicon substrate layer, and a metal-on-a-sheet antenna layer. The metal-on-a-sheet antenna layer includes a metal ground coplanar layer, a metal plate layer, a metal center patch, a first ground coplanar waveguide transmission line, a second ground coplanar waveguide transmission line, a third ground coplanar waveguide transmission line, and a coupled microstrip balun. The metal ground coplanar layer and the metal plate layer share a common center and both have a central cutout. The metal ground coplanar layer is stacked on the silicon substrate layer, and the metal plate layer is stacked on top of the metal ground coplanar layer. The metal center patch is located at the central cutout of the metal plate layer and is positioned between itself and the metal plate layer. The gap has a first grounded coplanar waveguide transmission line with one end connected to the metal center patch and the other end serving as an antenna transmitting port. The second grounded coplanar waveguide transmission line has one end connected to the metal center patch and the other end connected to the first input terminal of the coupled microstrip line balun. The third grounded coplanar waveguide transmission line has one end connected to the metal center patch and the other end connected to the second input terminal of the coupled microstrip line balun. The first and second output terminals of the coupled microstrip line balun serve as the first and second receiving ports of the antenna, respectively. The first and second receiving ports of the antenna are arranged adjacent to each other and are both located on the opposite side of the antenna transmitting port. The coupled microstrip balun includes a straight microstrip line, a first L-shaped microstrip line, and a second L-shaped microstrip line. The straight microstrip line, the first L-shaped microstrip line, and the second L-shaped microstrip line form an inverted T-shaped structure. The two ends of the straight microstrip line are respectively connected to a second grounded coplanar waveguide transmission line and a third grounded coplanar waveguide transmission line. One end of the first L-shaped microstrip line is connected to a metal grounded coplanar layer through a metal via, and the other end serves as the first output terminal of the coupled microstrip balun. One end of the second L-shaped microstrip line is connected to a metal grounded coplanar layer through a metal via, and the other end serves as the second output terminal of the coupled microstrip balun.

2. The dual-polarized millimeter-wave on-chip antenna according to claim 1, wherein: The antenna layer on the metal sheet also includes a metal isolation wall, which is arranged around the periphery of the metal plate layer and is connected to the metal plate layer at the first receiving port, the second receiving port, and the transmitting port of the antenna, respectively.

3. The dual-polarized millimeter-wave on-chip antenna according to claim 1, wherein: The metal plate layer is further provided with a first hollow, a second hollow, a third hollow, and a fourth hollow. The first hollow matches the shape of the first grounded coplanar waveguide transmission line and is used to place the first grounded coplanar waveguide transmission line. The second hollow matches the shape of the second grounded coplanar waveguide transmission line and is used to place the second grounded coplanar waveguide transmission line. The third hollow matches the shape of the third grounded coplanar waveguide transmission line and is used to place the third grounded coplanar waveguide transmission line. The fourth hollow matches the shape of the coupled microstrip line balun and is used to place the coupled microstrip line balun. There are gaps between the first grounded coplanar waveguide transmission line, the second grounded coplanar waveguide transmission line, the third grounded coplanar waveguide transmission line, and the coupled microstrip line balun and the metal plate layer.

4. The dual-polarized millimeter-wave on-chip antenna according to claim 1, wherein: The outer perimeter of the metal plate is square, and the inner perimeter is an octagonal hollow. The gap is octagonal, and its circumference is one antenna medium wavelength.

5. The dual-polarized millimeter-wave on-chip antenna according to claim 1, characterized in that: The metal center patch is octagonal, with the first horizontal side facing the antenna transmitting port connected to the first grounded coplanar waveguide transmission line, and the two vertical sides located on the first horizontal side connected to the second grounded coplanar waveguide transmission line and the third grounded coplanar waveguide transmission line, respectively.

6. The dual-polarized millimeter-wave on-chip antenna according to claim 1, wherein: A first hollowed-out groove is formed at the connection point between the metal center patch and the first grounded coplanar waveguide transmission line. A second hollowed-out groove is formed at the connection point between the metal center patch and the second grounded coplanar waveguide transmission line. A third hollowed-out groove is formed at the connection point between the metal center patch and the third grounded coplanar waveguide transmission line. A fourth hollowed-out groove is formed on the metal center patch opposite to the first hollowed-out groove. The first, second, third, and fourth hollowed-out grooves are all meander patterns.

7. The dual-polarized millimeter-wave on-chip antenna according to claim 2, wherein: The outer layer of the metal grounding coplanar layer is a square ring, and the inner layer is a square. The outer square ring and the inner square are connected at the antenna transmitting port, the first antenna receiving port, and the second antenna receiving port. The outer square ring is located below the metal isolation wall. The inner square has periodically arranged grids directly below the first grounding coplanar waveguide transmission line, the second grounding coplanar waveguide transmission line, the third grounding coplanar waveguide transmission line, and the coupled microstrip balun.

8. The dual-polarized millimeter-wave on-chip antenna according to claim 1, wherein: The metal plate layer is composed of several stacked metal layers, and the metal center patch has the same thickness as the topmost metal layer of the metal plate layer and is coplanar.

9. The dual-polarized millimeter-wave on-chip antenna according to claim 2, wherein: The metal partition wall is composed of several layers of metal stacked together, and the thickness is the same as the thickness of the metal plate layer.

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