CN118099776A - Transmit-receive common-caliber dual-polarized microstrip planar array antenna based on mixed feed network - Google Patents

Abstract

The invention discloses a receiving and transmitting common-caliber dual-polarized microstrip planar array antenna based on a hybrid feed network, which comprises a dual-polarized microstrip radiation array, a vertical polarization feed network and a horizontal polarization feed network. The dual-polarized microstrip radiation array is formed by two-dimensional array of microstrip radiation units, each microstrip radiation unit is a double-layer microstrip patch antenna with a longitudinal power division structure, a feed mode of slot coupling is adopted, and input ports are respectively a vertical polarization input port and a horizontal polarization input port; the vertical polarization feed network and the horizontal polarization feed network both comprise a waveguide feed network and a microstrip feed network; the waveguide feed network and the microstrip feed network are connected through a waveguide-microstrip line transition structure, and the output port of the vertical polarization feed network is connected to the vertical polarization input port of the microstrip radiation unit; the horizontal polarization feed network output port is connected to the horizontal polarization input port of the microstrip radiating element.

Description

Transmit-receive co-aperture dual-polarized microstrip planar array antenna based on hybrid feeding network

Technical Field

The invention relates to the field of antenna feed sources, and in particular to a transmitting and receiving co-aperture dual-polarized microstrip planar array antenna based on a hybrid feeding network.

Background technique

With the development of wireless communication technology, the demand for wireless broadband channels for high-speed data transmission is growing, especially in the field of mobile satellite communications, which lacks antennas that can meet the requirements of mobile use, specifically antennas with high gain, small size and light weight. The growing demand for high-throughput communications has led to the widespread application of millimeter waves in modern wireless communication systems. The millimeter wave frequency band is between microwaves and infrared light waves. Compared with traditional microwave systems, millimeter waves not only have the advantage of all-weather operation, but also can provide a wider range of available spectrum resources and more compact design size; compared with infrared light, millimeter waves not only inherit the advantages of large information capacity and high resolution, but are also less affected by the climate environment and can better utilize the atmospheric window for communication. For directional wireless data communication with satellites (for example, in the Ku or Ka band), since interference between adjacent satellites must be reliably prevented, extremely high requirements are placed on the transmission characteristics of the antenna. In mobile communication applications, the weight and size of the antenna are very important because they can reduce the payload of the mobile carrier and reduce the corresponding operating costs. In the field of satellite communications, management regulations stipulate that no interference will be generated between adjacent satellites during the directional transmission operation of mobile satellites. For this reason, the antenna that needs to be designed cannot exceed the value of a specific lobe width. This leads to strict requirements on antenna characteristics according to this indicator. As the beam width decreases, the separation angle between the antenna and the target satellite decreases, and the antenna gain increases accordingly. Usually, parabolic antennas with these characteristics are used. However, for most mobile applications, especially for aircraft, parabolic antennas are not suitable due to their large size. For example, in the case of commercial aircraft, the antenna is installed on the fuselage, and the large size of the parabolic antenna brings additional air resistance. Flat panel antennas, as an antenna that propagates electromagnetic waves in a specific direction, have different applications in many fields.

The most commonly used satellite communication flat antenna at present is the horn array antenna, which has the characteristics of high bandwidth, high efficiency, easy dual polarization, and common aperture for transmission and reception. However, since the antenna is an all-metal structure, the horn array antenna has a considerable weight and profile height, which is not conducive to portable storage. The microstrip antenna has a lower profile and lighter weight, which can better fit the application of satellite communication in motion. However, microstrip array antennas mostly use microstrip line power division networks. When the application frequency increases, the loss of the power division network will increase, resulting in a decrease in the gain of the antenna. In addition, in the high frequency band, the uplink and downlink frequency bands of satellite communication flat antennas have a large span, and the ratio of the center frequencies of the two bands is close to 1.5, which increases the design difficulty of the unit array of the flat antenna. Therefore, a satellite communication microstrip planar array antenna that can meet both the low profile requirements and the high gain and high efficiency requirements is needed.

Summary of the invention

In order to overcome the shortcomings of the prior art, the present invention proposes a dual-polarized microstrip planar array antenna with co-aperture for transmission and reception based on a hybrid feeding network. The antenna achieves high efficiency, low profile, and co-aperture characteristics of dual-polarized transmission and reception, and has the characteristics of high cross-polarization isolation and compact structure.

The object of the present invention is achieved through the following technical solutions: a transmitting and receiving co-aperture dual-polarized microstrip planar array antenna based on a hybrid feeding network, comprising: a dual-polarized microstrip radiating array, a vertically polarized feeding network and a horizontally polarized feeding network;

The dual-polarized microstrip radiating array is composed of a two-dimensional array of microstrip radiating units, each of which is a double-layer microstrip patch antenna with a longitudinal power division structure, adopts a slot-coupled feeding method, and has input ports that are a vertical polarization input port and a horizontal polarization input port respectively;

The vertical polarization feeding network comprises a first waveguide feeding network and a first microstrip feeding network; the first waveguide feeding network and the first microstrip feeding network are connected via a waveguide-microstrip line transition structure, and the vertical polarization feeding network output port is connected to the vertical polarization input port of the microstrip radiation unit;

The horizontally polarized feeding network includes a second waveguide feeding network and a second microstrip feeding network; the second waveguide feeding network and the second microstrip feeding network are connected through a waveguide-microstrip line transition structure, and the vertically polarized feeding network output port is connected to the vertically polarized input port of the microstrip radiating unit.

Furthermore, the microstrip radiation unit is composed of a radiation layer, a driving layer, a coupling layer, a vertical polarization feeding layer, an isolation layer and a horizontal polarization feeding layer connected in sequence.

Furthermore, the radiation layer is formed by printing a radiation patch on the first dielectric substrate.

Furthermore, the driving layer includes a second dielectric substrate for exciting vertically polarized waves and horizontally polarized waves, and its driving function is realized by a driving patch printed on the second dielectric substrate or a coupling window of the coupling layer.

Furthermore, the coupling layer is composed of a third dielectric substrate and a metal ground plane with a coupling window, and the coupling window is rectangular or cross-shaped. The driving layer, the radiation layer and the coupling layer form a longitudinal power division structure.

Further, the vertical polarization feeding layer is composed of a fourth dielectric substrate and a vertical polarization microstrip line, and the vertical polarization feeding layer and the dielectric substrates above and below it constitute a vertical polarization microstrip line port of the microstrip radiation unit;

The vertically polarized microstrip line is inserted under the coupling layer, and its head end is at the edge of the fourth dielectric substrate, and the end length exceeds the coupling center by 1-4 mm, and the coupling layer excites the driving patch to generate electromagnetic waves in a vertically polarized mode.

Furthermore, the isolation layer is composed of a fifth dielectric substrate and a metal ground plane with a horizontal polarization coupling slot; the coupling window of the metal ground plane is rectangular and is used to couple the electromagnetic waves of the horizontal polarization feeding layer while ensuring the isolation of the two input ports.

Furthermore, the horizontally polarized feeding layer is composed of a sixth dielectric substrate and a horizontally polarized microstrip line; the horizontally polarized feeding layer and the dielectric substrates above and below it constitute a horizontally polarized input port of a microstrip radiation unit; the ends of the microstrip lines all exceed the center of the rectangular slot of the isolation layer, and the driving patch is stimulated to generate electromagnetic waves in a horizontally polarized mode; the horizontally polarized microstrip line can be transformed into a T-type structure from a single feed line structure to a dual feed line structure, thereby increasing the coupling amount.

Furthermore, the microstrip radiation unit has a dual polarization mode, namely a vertical polarization mode and a horizontal polarization mode;

The operating frequencies of the vertical polarization mode and the horizontal polarization mode include single-band operation and dual-band operation;

When the single-band operation is performed, the operating frequency of the vertical polarization mode and the operating frequency of the horizontal polarization mode correspond to the receiving frequency or the transmitting frequency respectively; when the dual-band operation is performed, the operating frequency of the vertical polarization mode and the operating frequency of the horizontal polarization mode include both the receiving frequency and the transmitting frequency.

Further, in the vertical polarization feeding network, the first microstrip power division network covers all the final 1-to-4 structures of the vertical polarization feeding network, and the first waveguide power division feeding network covers the remaining power division structures of the vertical polarization feeding network;

In the horizontal polarization feeding network, the second microstrip power division network covers all the final 1-to-4 structures of the horizontal polarization feeding network, and the second waveguide power division feeding network covers the remaining power division structures of the horizontal polarization feeding network.

Compared with the prior art, the present invention has the following advantages:

1. The present invention adopts a double-layer microstrip patch antenna with a longitudinal power division structure as a microstrip radiation unit. This structure can not only expand the bandwidth of the antenna, but also expand the arrangement period of the antenna unit.

2. The present invention adopts a hybrid feeding network, which has the characteristics of low profile and low loss, and realizes the compact arrangement of the array. Compared with the waveguide feeding network, the hybrid power division feeding network makes full use of the vertical space, avoiding the problem of large waveguide power division network arrangement and grating lobes in the radiation pattern. And the use of microstrip line structure as the final 1-to-4 structure effectively controls its own profile height; compared with the microstrip line feeding network, the hybrid power division feeding network uses a waveguide structure in the front stage, which effectively reduces the loss of the feeding network and provides a guarantee for the high efficiency of the antenna.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a schematic diagram of a three-dimensional structure of a transmitting and receiving co-aperture dual-polarization microstrip planar array based on hybrid power division feeding implemented in an example of the present invention;

FIG2 is an exploded schematic diagram of a three-dimensional structure of a radiating element of a transmit-receive co-aperture dual-polarization microstrip planar array based on hybrid power division feeding implemented in an example of the present invention;

3 is a schematic diagram of a two-dimensional structure of a radiating element of a transmit-receive co-aperture dual-polarization microstrip planar array based on hybrid power division feeding implemented in an example of the present invention;

FIG4 is a schematic diagram of a three-dimensional structure of a hybrid feeding structure of a transmitting and receiving co-aperture dual-polarization microstrip planar array based on hybrid power division feeding implemented in an example of the present invention;

5 is a diagram showing the simulation results of the radiating elements of the transmitting and receiving co-aperture dual-polarized microstrip planar array based on hybrid power division feeding implemented in an example of the present invention;

6 is a simulation directional diagram of a transmit-receive co-aperture dual-polarization microstrip planar array based on hybrid power division feeding implemented in an example of the present invention at 19.45 GHz;

7 is a simulation directional diagram of a transmit-receive co-aperture dual-polarization microstrip planar array based on hybrid power division feeding implemented in an example of the present invention at 29.025 GHz;

8 is a comparison diagram between the simulated gain and the theoretical gain of the transmit-receive co-aperture dual-polarization microstrip planar array based on hybrid power division feeding implemented in an example of the present invention;

9 is a schematic diagram of a two-dimensional structure of a radiating element driving layer patch removed from a transmit-receive co-aperture dual-polarization microstrip planar array based on hybrid power division feeding implemented in an example of the present invention.

Detailed ways

The invention discloses a dual-polarized microstrip planar array antenna with co-aperture for transmission and reception based on a hybrid feeding network. The antenna realizes high efficiency, low profile, and co-aperture characteristics of dual-polarized transmission and reception, and has the characteristics of high cross-polarization isolation and compact structure.

Referring to Figure 1, the transmit-receive co-aperture dual-polarized microstrip planar array antenna based on a hybrid feeding network implemented in the present invention includes: a dual-polarized microstrip radiating array 1, a vertically polarized feeding network 2 and a horizontally polarized feeding network 3; the vertically polarized feeding network 2 includes a first waveguide feeding network 21 and a first microstrip feeding network 22; the horizontally polarized feeding network 3 includes a second waveguide feeding network 31 and a second microstrip feeding network 32.

The dual-polarized microstrip radiation array is composed of a two-dimensional array of microstrip radiation units. Referring to FIG2 , it is an exploded schematic diagram of the microstrip radiation unit. Each microstrip radiation unit is a dual-frequency dual-polarized antenna, which adopts a slot-coupled feeding form and has two input ports, namely a vertical polarization input port 17 and a horizontal polarization input port 18, which are dielectric microstrip line structures. It is composed of a six-layer structure, including a radiation layer 11, a driving layer 12, a coupling layer 13, a vertical polarization feeding layer 14, an isolation layer 15, and a horizontal polarization feeding layer 16.

Referring to FIG. 3 , it is a schematic plan view of each layer of the radiation unit of the dual-polarization microstrip radiation array 1 .

The radiation layer 11 is composed of a first dielectric substrate 111 and four radiation patches 112. The radiation patches 112 are printed on the first dielectric substrate 111.

The driving layer 12 is composed of a second dielectric substrate 121 and a driving patch 122. The driving patch 122 is printed on the second dielectric substrate to excite vertically polarized waves and horizontally polarized waves. The patches of the radiation layer and the patches of the driving layer form a longitudinal power division structure, which is used to uniformly drive the electromagnetic waves radiated by the driving layer to ensure that the radiation pattern does not have grating lobes.

The coupling layer 13 is composed of a third dielectric substrate 131 and a metal ground plane 132 with a coupling window. The coupling window of the metal ground plane can be rectangular or cross-shaped, and is used to couple electromagnetic waves of the vertical polarization feeding layer and the horizontal polarization feeding layer.

The vertical polarization feeding layer 14 is composed of a fourth dielectric substrate 141 and a vertical polarization microstrip line 142. The vertical polarization microstrip line 142 and the dielectric substrates above and below it constitute a vertical polarization microstrip line port 17 of the microstrip radiation unit. The vertical polarization microstrip line 142 is inserted under the coupling layer 13, and its head end is at the edge of the fourth dielectric substrate 141, and the end length exceeds the center of the coupling layer 13 by 1-4 mm, and the coupling layer 13 excites the driving patch 122 to generate electromagnetic waves in a vertical polarization mode.

The isolation layer 15 is composed of a fifth dielectric substrate 151 and a metal ground plane 152 with a horizontal polarization coupling slot. The coupling window of the metal ground plane is rectangular and is used to couple the electromagnetic waves of the horizontal polarization feeding layer while ensuring the isolation of the two input ports.

The horizontal polarization feeding layer 16 is composed of a sixth dielectric substrate 161 and a horizontal polarization microstrip line 162. The horizontal polarization feeding layer 16 and the dielectric substrates above and below it constitute the horizontal polarization input port 18 of the microstrip radiation unit. The ends of the microstrip lines are 1 to 4 mm beyond the center of the rectangular slot of the isolation layer 15, and the radiation patch 112 is stimulated to generate electromagnetic waves in a horizontal polarization mode. The horizontal polarization microstrip line can also be T-transformed from a single feed line structure to a dual feed line structure to increase the coupling amount.

Referring to FIG. 4 , there is a schematic diagram of the structures of the vertical polarization feeding network 2 and the horizontal polarization feeding network 3 .

The input port of the first waveguide feeding network 21 is a rectangular waveguide structure, and the vertical polarization feeding network output port 211 is connected to the first microstrip feeding network 22 through a waveguide suspension strip line transition structure to form a hybrid feeding structure. The first microstrip feeding network 22 is then connected to the vertical polarization input port 17 of the radiating array element through a microstrip power splitter line. The first microstrip power splitter network covers all the final 1-to-4 structures of the vertical polarization feeding network, and the first waveguide power splitter feeding network covers the remaining power splitter structures of the vertical polarization feeding network.

The input port of the second waveguide feeding network 31 is a rectangular waveguide structure, and the output port 311 of the horizontal polarization feeding network is connected to the second microstrip feeding network 32 through a waveguide suspension strip line transition structure to form a hybrid feeding structure. The second microstrip feeding network 32 is then connected to the horizontal polarization input port 18 of the radiating array element through a microstrip power splitter line. The second microstrip power splitter network covers all the last-stage 1-to-4 structures of the horizontal polarization feeding network, and the second waveguide power splitter feeding network covers the remaining power splitter structures of the horizontal polarization feeding network.

Refer to Figure 5, which is the reflection coefficient simulation result of the microstrip radiating unit. From the results, it can be seen that the reflection coefficients of the vertical polarization input port and the horizontal polarization input port of the microstrip radiating unit are both less than -10dB in the frequency bands of 17.7GHz~21.2GHz and 27.5GHz~31GHz, realizing the characteristics of dual-frequency operation.

Referring to Figure 6, the array simulation results of the transmit-receive co-aperture dual-polarized microstrip planar array antenna based on the hybrid feeding network are shown, which basically demonstrates the availability of the antenna. Figures 6 and 7 show the simulated radiation patterns of the antenna at 19.45GHz and 29.25GHz. At each frequency, whether it is fed by the vertical polarization port or the horizontal polarization port, the radiation pattern has good consistency, and the first sidelobe level is around -13.6dB; the main lobe beam width is 12° at 19.45GHz; the main lobe beam width is 8° at 29.25GHz, which proves that the antenna has good dual-frequency dual-polarization radiation characteristics. Figure 8 shows the comparison between the simulated gain and the theoretical gain of the antenna. The antenna gain is 0.1-0.3dBi lower than the theoretical value, and the antenna efficiency is above 95%, which proves the high efficiency and low loss characteristics of the antenna.

The design reference example is a satellite communication microstrip planar array antenna that meets both the low profile requirements and the high gain and high efficiency requirements.

Embodiment 2:

The radiation unit of the dual-polarized microstrip radiation array 1 can also have another implementation. Referring to Figure 9, an exploded schematic diagram of the second implementation is given, which adopts the form of slot-coupled radiation and has two input ports, namely a vertical polarization input port 17 and a horizontal polarization input port 18, which is a dielectric microstrip line structure. It is composed of a six-layer structure, including a radiation layer 11, a driving layer 12, a coupling layer 13, a vertical polarization feeding layer 14, an isolation layer 15 and a horizontal polarization feeding layer 16. The vertical polarization feeding network output port 211 is connected to the vertical polarization input port 17, and the horizontal polarization feeding network output port 311 is connected to the horizontal polarization input port 18. The patch of the driving layer 12 is removed, and the coupling gap of the coupling layer 13 plays the role of a driving layer patch.

It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, horizontal, vertical, etc.), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

The above is a specific implementation of the present invention. Those skilled in the art can produce a dual-polarized common-aperture horn array antenna by applying the method disclosed in the present invention and some alternative methods without creative labor. The structure of the present invention has the characteristics of low profile, low loss, simple design and easy processing.

The above embodiments are used to illustrate the present invention rather than to limit the present invention. Any modification and change made to the present invention within the spirit of the present invention and the protection scope of the claims shall fall within the protection scope of the present invention.

Claims (10)

1. The receiving and transmitting common-caliber dual-polarized microstrip planar array antenna based on the mixed feed network is characterized by comprising: a dual polarized microstrip radiating array, a vertical polarization feed network, and a horizontal polarization feed network;

The dual-polarized microstrip radiation array is formed by two-dimensional array of microstrip radiation units, each microstrip radiation unit is a double-layer microstrip patch antenna with a longitudinal power division structure, a feed mode of slot coupling is adopted, and input ports are respectively a vertical polarization input port and a horizontal polarization input port;

The vertical polarization feed network comprises a first waveguide feed network and a first microstrip feed network; the first waveguide feed network is connected with the first microstrip feed network through a waveguide-microstrip line transition structure, and the output port of the vertical polarization feed network is connected to the vertical polarization input port of the microstrip radiation unit;

The horizontal polarization feed network comprises a second waveguide feed network and a second microstrip feed network; the second waveguide feed network and the second microstrip feed network are connected through a waveguide-microstrip line transition structure, and the output port of the horizontal polarization feed network is connected to the horizontal polarization input port of the microstrip radiating element.

2. The receiving and transmitting co-aperture dual-polarized microstrip planar array antenna based on the mixed feed network as claimed in claim 1, wherein the microstrip radiating element is formed by sequentially connecting a radiating layer, a driving layer, a coupling layer, a vertical polarization feed layer, an isolation layer and a horizontal polarization feed layer.

3. The co-aperture dual-polarized microstrip planar array antenna based on the mixed feed network of claim 2, wherein said radiation layer is formed by printing a radiation patch on a first dielectric substrate.

4. The co-aperture dual-polarized microstrip planar array antenna of claim 3, wherein said driving layer comprises a second dielectric substrate for exciting vertical polarized waves and horizontal polarized waves, and the driving function is realized by a driving patch printed on the second dielectric substrate or a coupling window of the coupling layer.

5. The receiving and transmitting co-aperture dual-polarized microstrip planar array antenna based on the mixed feed network as claimed in claim 2, wherein said coupling layer is composed of a third dielectric substrate and a metal ground plane with a coupling window, said coupling window is rectangular or cross-shaped for coupling a vertically polarized wave with a horizontally polarized wave; the driving layer, the radiation layer and the coupling layer form a longitudinal power division structure.

6. The receiving and transmitting co-aperture dual-polarized microstrip planar array antenna based on a mixed feed network as claimed in claim 2, wherein said vertical polarization feed layer is composed of a fourth dielectric substrate and a vertical polarization microstrip line, and said vertical polarization feed layer and its upper and lower dielectric substrates compose a vertical polarization microstrip line port of a microstrip radiation unit;

The vertical polarization microstrip line is inserted below the coupling layer, the head end of the vertical polarization microstrip line is arranged at the edge position of the fourth dielectric substrate, the tail end of the vertical polarization microstrip line exceeds the coupling center by 1-4 mm, and the driving patch is excited by the coupling layer to generate electromagnetic waves in a vertical polarization mode.

7. The receiving and transmitting co-aperture dual-polarized microstrip planar array antenna based on the mixed feed network as claimed in claim 2, wherein said isolation layer is composed of a fifth dielectric substrate and a metal ground plane with a horizontal polarization coupling slot; the coupling window of the metal ground plane is rectangular and is used for coupling electromagnetic waves of the horizontal polarization feed layer and guaranteeing isolation of two input ports.

8. The receiving and transmitting co-aperture dual-polarized microstrip planar array antenna based on the mixed feed network as claimed in claim 7, wherein said horizontal polarization feed layer is composed of a sixth dielectric substrate and a horizontal polarization microstrip line; the horizontal polarization feed layer and the upper and lower dielectric substrates form a horizontal polarization input port of the microstrip radiation unit; the tail ends of the microstrip lines exceed the center of the rectangular groove of the isolation layer, and the driving patch is excited to generate electromagnetic waves in a horizontal polarization mode; the horizontal polarization microstrip line can perform T-type conversion, and the coupling amount is increased from a single feeder line structure to a double feeder line structure.

9. The co-aperture dual-polarized microstrip planar array antenna based on the mixed feed network as claimed in claim 1, wherein said microstrip radiating element has dual polarization modes, i.e., a vertical polarization mode and a horizontal polarization mode;

the working frequencies of the vertical polarization mode and the horizontal polarization mode comprise single-frequency operation and double-frequency operation;

When the single-band works, the working frequency of the vertical polarization mode and the working frequency of the horizontal polarization mode respectively correspond to the receiving frequency or the transmitting frequency; when the dual-band is in operation, the operating frequency of the vertical polarization mode and the operating frequency of the horizontal polarization mode simultaneously comprise a receiving frequency and a transmitting frequency.

10. The receiving and transmitting common-caliber dual-polarized microstrip planar array antenna based on the mixed feed network according to claim 1, wherein in the vertical polarization feed network, a first microstrip power division network covers all final-stage 1-division 4 structures of the vertical polarization feed network, and a first waveguide power division feed network covers the rest of the power division structures of the vertical polarization feed network;

In the horizontal polarization feed network, the second microstrip power division network covers all final stage 1-4 structures of the horizontal polarization feed network, and the second waveguide power division feed network covers the other stage power division structures of the horizontal polarization feed network.