CN116325363B

CN116325363B - Multi-band common-caliber antenna and communication equipment

Info

Publication number: CN116325363B
Application number: CN202080105245.4A
Authority: CN
Inventors: 邓长顺; 樊磊; 杨昌兴; 王江
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2020-10-12
Filing date: 2020-10-12
Publication date: 2025-02-21
Anticipated expiration: 2040-10-12
Also published as: EP4220864A1; JP7581503B2; JP2023544437A; KR20230085169A; KR102760353B1; WO2022077185A1; CN116325363A; EP4220864A4

Abstract

A multi-band common aperture antenna and communication equipment, the multi-band common aperture antenna comprises a coupling array element, a frequency division and combining unit, a low-frequency feeding unit, and a high-frequency feeding unit; the coupling array element is arranged on a reflector; the frequency division and combining unit is connected to the coupling array element, the frequency division and combining unit comprises a frequency division and combining layer, the frequency division and combining layer comprises a frequency division and combining device, the frequency division and combining device comprises an antenna port, a high-frequency port, and a low-frequency port, when there is one layer, the antenna port is connected to the coupling array element, the low-frequency port is connected to the low-frequency feeding unit, and the high-frequency port is connected to the high-frequency feeding unit; when there are at least two layers, between two adjacent layers, the upper low-frequency port is connected to the lower antenna port, the first antenna port is connected to the coupling array element, the first high-frequency port is connected to the high-frequency feeding unit, the last low-frequency port is connected to the low-frequency feeding unit, and the last high-frequency port is connected to the high-frequency feeding unit. By using the above technical solution, the antenna has multi-frequency expansion capability and has a wide beam scanning capability in each frequency band.

Description

Multi-band common-caliber antenna and communication equipment

Technical Field

The present application relates to the field of base station antennas, and in particular, to a multiband common-caliber antenna and a communication device.

Background

In the evolution process of the base station antenna network, the number of the antenna surfaces is increased, the physical space for arranging the antenna surfaces on the iron tower is also reduced, and the antenna surfaces are platforms for the positions of the antennas. Therefore, the multi-frequency base station antenna is the mainstream of the current antenna design. Under the condition of limited antenna caliber, the improvement of the integration level of the antenna frequency as much as possible is a trend of the development of antenna technology. At present, most 4G multi-frequency base station antennas do not have wide-angle beam scanning capability, while 5G MIMO (multiple-in multipleout, multiple-in and multiple-out) array antennas have flexible 3D-M-MIMO beam forming, wide-angle beam scanning capability and high frequency spectrum efficiency, and can effectively improve the coverage range of the antennas.

In the multi-frequency array antenna, wide-angle beam scanning is a difficulty and a challenge of the design of the array antenna, and it is difficult to design the array antenna which combines cost scanning and multi-frequency coverage at present, and the array antenna is difficult to be used in large scale and commercial use. Thus, phased array antennas and 5G MIMO antennas that currently enable wide angle beam scanning are still single frequency, narrowband designs. For the newly established 5G low frequency band, although the 5G high speed can not be supported, the high frequency coverage can be provided, so that the high frequency band is favored by operators, but the low frequency band is a plurality of octaves from the high frequency band, the low frequency band is difficult to integrate on the existing high frequency antenna, and if the base station is required to meet the requirement of the 5G low frequency band, the antenna meeting the 5G low frequency band needs to be rearranged. But there is no extra space on the pylon to rearrange the new antennas and the rearrangement of the antennas also requires additional costs. Therefore, it is currently difficult to design an array antenna that can achieve both wide angle beam scanning and satisfies multiple frequencies, particularly non-integer frequency ratios in multiple frequencies.

Disclosure of Invention

The multi-band common-caliber antenna and the communication equipment provided by the application are used for enabling the antenna array to have good multi-band expansion capability and keeping good wide-angle beam scanning capability in different frequency bands.

In a first aspect, a multiband common aperture antenna is provided, including a plurality of coupling array elements, a frequency division combining unit, a low frequency feeding unit, and a high frequency feeding unit, wherein:

Each coupling array element is arranged on the reflecting plate;

The frequency division and combination unit is connected with the plurality of coupling array elements, the frequency division and combination unit comprises at least one layer of frequency division and combination layer, each layer of frequency division and combination layer comprises at least one frequency division and combination device, each frequency division and combination device comprises an antenna port, at least one high-frequency port and at least one low-frequency port, the plurality of high-frequency ports form at least one high-frequency port group, and the plurality of low-frequency ports form at least one low-frequency port group;

When the frequency division and combination unit comprises one layer of frequency division and combination layer, the antenna ports of the frequency division and combination unit are connected with the coupling array elements, the plurality of low-frequency ports are connected with the low-frequency feed unit, and the plurality of high-frequency ports are connected with the high-frequency feed unit;

When the frequency division and combination unit comprises at least two layers of frequency division and combination layers, a plurality of low-frequency ports of an upper layer are connected with antenna ports of a lower layer between every two adjacent layers, the antenna ports of a first layer frequency division and combination unit are connected with the coupling array elements, a plurality of high-frequency ports of a first layer frequency division and combination unit are connected with the high-frequency feed unit, a plurality of low-frequency ports of a last layer frequency division and combination unit are connected with the low-frequency feed unit, and the high-frequency ports of a last layer frequency division and combination unit are connected with the high-frequency feed unit;

A low frequency feeding unit for providing a low frequency signal feed;

and a high frequency feeding unit for feeding at least one frequency signal higher than the low frequency signal.

In the scheme, the antenna has good multi-frequency expansion capability and can keep good wide-angle beam scanning capability in different frequency bands through the combination of different low-frequency ports and high-frequency ports. The number of feed ports is reduced due to the reconfiguration of the feed unit structure, so that hardware overhead and power consumption are also reduced. In addition, grating lobes can be avoided in the beam scanning process. In addition, the number of the feed ports is reduced due to the reconfiguration of the feed unit structure, so that the hardware cost and the power consumption are also reduced.

In a specific embodiment, the coupling array elements are grouped according to different ports to form reconstruction units of different frequency bands, the coupling array elements corresponding to the low-frequency ports in the low-frequency port group jointly form the low-frequency reconstruction unit, and the coupling array elements corresponding to the high-frequency ports in the high-frequency port group jointly form the high-frequency reconstruction unit.

In the scheme, the low-frequency ports and the high-frequency ports are recombined to form units with different physical apertures, the scanning capability of wide-angle beams of each frequency band is improved, and meanwhile, the cost and the complexity of the antenna can be effectively reduced, so that the antenna has good spread spectrum characteristics, and the scheme for constructing the multi-frequency band common-aperture antenna with integer ratio and non-integer frequency ratio is provided.

In a specific embodiment, the distance d between the centers of every two adjacent coupled array elements may be such that:

n₁*d≤0.5λ₁;

Wherein n ₁ is the number of the high-frequency ports in the high-frequency port group, lambda ₁ is the wavelength corresponding to the high-frequency signal input by the high-frequency feed unit, and n ₁ is a positive integer.

By determining the distance d between the centers of every two adjacent coupling array elements, the grating lobes can be prevented from occurring in the beam scanning process of the high-frequency band.

In a specific embodiment, if the maximum scan angle of the multiband common aperture antenna is θ _max, the distance d between the centers of every two adjacent coupled array elements may be satisfied:

By setting the distance d between the centers of every two adjacent coupling array elements, the grating lobes can be avoided under the condition that the high-frequency band has better wide-angle beam scanning capability.

In a specific embodiment, the number n ₂ of low-frequency ports in the low-frequency port group may satisfy:

n₂*d≤0.5λ₂;

wherein lambda ₂ is the wavelength corresponding to the low-frequency signal input by the low-frequency feed unit, n ₂ is a positive integer, and d is the distance between the centers of every two adjacent coupling array elements.

Because the distance d between the centers of every two adjacent coupling array elements is determined, the grating lobes can be avoided in the beam scanning process of the low frequency band by setting the number n ₂ of the low frequency ports in the low frequency port group.

In a specific embodiment, if the maximum scan angle of the multiband common aperture antenna is θ _max, the number n ₂ of low frequency ports in the low frequency port group may satisfy:

by setting the number n ₂ of the low-frequency ports in the low-frequency port group, the grating lobes can be avoided under the condition that the low-frequency band has better wide-angle beam scanning capability.

In a specific embodiment, the low-frequency feeding unit and the high-frequency feeding unit can be provided with phase shifting units, each phase shifting unit is used for adjusting the phase lag/lead of electromagnetic waves radiated by the low-frequency feeding unit and the high-frequency feeding unit to the set phase corresponding to the coupling array element, and the phase shifting units can be any one or a plurality of structures including a digital phase shifter, an analog phase shifter and a hybrid phase shifter.

And by utilizing the various phase shifting units, the phase lag/lead of the electromagnetic waves radiated by the low-frequency power supply unit and the high-frequency power supply unit is regulated to the set phase corresponding to the coupling array element so as to form beams in different directions, thereby completing beam scanning.

In a specific embodiment, the coupling element comprises at least one dipole element, the dipole element is parallel to the polarization direction of the coupling element, and coupling capacitors are arranged at two sides of the tail end of the dipole element. By setting the direction of the dipole array elements, the coupling array elements can have at least one polarization direction to compose more polarization types.

In a specific embodiment, when the coupling element comprises two dipole elements, the dipole elements are orthogonally disposed. By arranging dipole array elements in an orthogonal mode, the coupling array elements can have dual polarization characteristics in different directions such as vertical and horizontal directions, +/-45 degrees directions and the like.

In a specific embodiment, the frequency division combiner may comprise any one or more of a frequency divider, a diplexer, a filter.

The number of the low-frequency and high-frequency ports of the frequency division combiner can be expanded by setting the number of interfaces of the frequency divider, the frequency divider and the filter, and different modes of connection can be carried out, and the frequency divider is not limited to a double-frequency type, and can also use a frequency division device of a three-frequency or multi-frequency type, so that the cost and the complexity of the antenna can be reduced more effectively, and the antenna has good frequency expansion characteristics.

In a second aspect, a communication device is provided, where the communication device includes any of the above multi-band co-aperture antennas, and the above design enables the antenna to have good multi-band expansion capability, and to maintain good wide-angle beam scanning capability in different frequency bands. In addition, grating lobes can be avoided in the beam scanning process. In addition, since the number of the feeding ports is reduced due to the reconfiguration of the feeding unit structure, hardware overhead and power consumption can also be reduced.

Drawings

Fig. 1 is a schematic diagram of a base station;

FIGS. 2a and 2b are schematic diagrams of a coaxial design of a multiband common aperture antenna;

FIGS. 2c and 2d are schematic diagrams of a multi-band common aperture antenna designed in a flower arrangement manner;

Fig. 2e is a schematic diagram of a feeding structure corresponding to the structure shown in fig. 2a to 2 d;

FIG. 2f is a schematic diagram of a multi-band common-aperture antenna designed by using a reflector separation technique;

FIG. 2g is a schematic diagram of a multi-band common aperture antenna designed using broadband element sharing technology;

FIG. 2h is a schematic diagram of a feed structure corresponding to the structure shown in FIG. 2 g;

FIG. 2i is a schematic diagram of a multi-band co-aperture antenna designed using a tightly coupled phased array technique;

FIG. 2j is a schematic diagram illustrating the isolation of the structure shown in FIG. 2i in different frequency bands;

FIG. 2k is a schematic diagram of a feed structure corresponding to the structure shown in FIG. 2 i;

FIG. 3a is a schematic diagram of a multi-band common aperture antenna;

FIG. 3b is a schematic diagram of a multi-band co-aperture antenna structure including a phase shifting element;

Fig. 4a is a beam forming schematic of an analog phase shifter;

fig. 4b is a beam forming schematic of the digital phase shifter;

fig. 4c is a beam forming schematic of a hybrid phase shifter;

FIGS. 5 a-5 d are schematic diagrams of a dual band antenna;

fig. 6 is a schematic diagram of a tri-band antenna;

FIGS. 7 a-7 i are schematic diagrams of planar array type multi-band co-aperture antennas;

FIG. 8a is a schematic diagram of a periodic array of elements;

FIG. 8b is a schematic diagram of an aperiodic array;

FIG. 8c is a schematic diagram of an array element arrangement including dummy elements;

FIGS. 9a to 9b are schematic diagrams of dual polarization coupling array elements;

FIG. 10 is a schematic diagram of a four-band monopole planar array;

FIG. 11 is a schematic diagram of a reflective array antenna;

FIG. 12 is a schematic view of a smart reflective surface;

Fig. 13 is a schematic view of a reflection unit.

Detailed Description

In order to make the objects, technical solutions and advantages of the present application more apparent, the present application will be further described in detail with reference to the accompanying drawings.

The following explains the words to which the present application relates or may relate:

1. at least one, means one, or more than one, i.e., including one, two, three and more than one;

2. Plural means two, or more than two, i.e., including two, three, four and more than two;

3. Connected, meaning coupled, includes directly connected or indirectly connected via other devices to achieve electrical communication;

4. Grating lobes refer to lobes generated by the same-direction superposition in multiple directions when the unit interval of the array antenna is large enough besides the main lobe;

5. Phased array radar (PHASED ARRAY RADAR, PAR) is a phased array radar in which a large number of individually controlled small antenna elements are arranged in an array, each antenna element being controlled by an independent phase shift switch, and by controlling the phase of the transmissions of each antenna element, beams of different phases can be synthesized. Electromagnetic waves emitted by all antenna units of the phased array are synthesized into a nearly straight radar main lobe by an interference principle;

6. The microwave wireless energy transmission technology is a mode of energy transmission, has good application prospect in the fields of satellite energy transmission, directional energy weapons, biomedicine, two-place power transmission and the like, and a receiving antenna and a rectifying circuit in the microwave wireless energy transmission technology are two key research technical points;

7. the direction backtracking antenna is an antenna array, and particularly relates to an antenna which preferentially returns power to a source direction when receiving an incoming wave direction signal;

8. a tightly coupled phased array (tightly coupled PHASED ARRAY, TCPA), an array antenna that uses strong coupling between elements to boost the phased array bandwidth;

9. The common port surface works by adopting the same caliber with different frequency bands of the antenna, and compared with a non-common port surface antenna, the common port surface antenna can reasonably design a plurality of antennas with different frequency and polarization characteristics in the same caliber, has the performance of multi-frequency and multi-polarization work while keeping the compact structure of the antenna, and is a development trend of future antennas.

In order to facilitate understanding of the multi-band co-aperture antenna provided by the embodiments of the present application, application scenarios thereof will be described first, and the multi-band co-aperture antenna provided by the embodiments of the present application is suitable for use in a mobile communication system, where the mobile communication system includes, but is not limited to, a global system for mobile communication (global system of mobile communication, GSM) system, a code division multiple access (code division multiple access, CDMA) system, a wideband code division multiple access (wideband code division multiple access, WCDMA) system, a general packet radio service (GENERAL PACKET radio service, GPRS), a long term evolution (long term evolution, LTE) system, an LTE frequency division duplex (frequency division duplex, FDD) system, an LTE time division duplex (time division duplex, TDD), a universal mobile communication system (universal mobile telecommunication system, UMTS), a worldwide interoperability for microwave access (worldwide interoperability for microwave Access, wiMAX) communication system, a fifth generation (5th generation,5G) system or a New Radio (NR), and future (6th generation,6G) system, etc.

The multi-band co-aperture antenna of the present application can also be used in phased array radar applications, for example. The multi-band common-caliber antenna is used as a phased array antenna of the phased array radar, so that the scanning angle of the radar can be increased, the scanning flexibility can be improved, and the performance is more reliable.

The multi-band common-caliber antenna can also be applied to the field of microwave wireless energy transmission. The multi-band common-caliber antenna is used as a receiving antenna for microwave wireless energy transmission and is used for adding a reflector function, and energy is received and converted by connecting a microwave rectifying circuit, so that the reflection surface characteristics of other frequency bands can be reconstructed under the condition that the receiving characteristics of the energy transmission frequency bands are not affected, and the advantages of the reflecting reconstruction unit array/reflector antenna are considered while the wireless energy transmission is realized.

The multi-band common-caliber antenna design can also be applied to the field of directional backtracking antennas. The working mode of the direction backtracking antenna determines that the array antenna needs to have a wider wave speed scanning angle and frequency bandwidth, but based on the traditional direction backtracking antenna, the complexity and cost of the system are greatly increased due to the huge radio frequency transceiver component of the wave beam of the traditional direction backtracking antenna, and the application in the direction backtracking antenna is limited. The application can be extended onto an antenna array of a directional trace-back antenna, takes the multi-band common-caliber antenna in the embodiment as an array antenna, realizes the multi-band directional trace-back antenna, expands the bandwidth, loads a coupler on the multi-band common-caliber antenna, connects the coupling array element on the multi-band common-caliber antenna with absorption load, automatically tracks and aligns interference signals through the calibration of the coupler, reduces the array RCS (radar cross section), and improves the signal safety.

The multi-band co-aperture antenna provided by the embodiment of the application can also be applied to a wireless network system, wherein the multi-band co-aperture antenna can be applied to a base station subsystem (base btation bubsystem, BBS), a terrestrial radio access network (UMTS terrestrial radio access network, UTRAN, UMTS, universal mobile telecommunications system, universal mobile communication system) or an evolved terrestrial radio access network (evolved universal terrestrial radio access, E-UTRAN), and is further used for covering a cell of a wireless signal to realize the connection between UE and a radio frequency end of the wireless network.

The multi-band common-caliber antenna related to the embodiment can also be arranged in the wireless access network equipment to realize signal receiving and transmitting. In particular, the radio access network device may include, but is not limited to, a base station 100 as shown in fig. 1. The base station 100 may be a base station (base transceiver station, BTS) in a GSM or CDMA system, a base station (NodeB, NB) in a WCDMA system, an evolved base station (evolutional NodeB, eNB or eNodeB) in an LTE system, a radio controller in a cloud radio access network (cloud radio access network, CRAN) scenario, or the base station 100 may be a relay station, an access point, a vehicle-mounted device, a wearable device, a base station in a 5G network, or a base station in a PLMN network for future evolution, etc. For example, the new wireless base station, embodiments of the present application are not limited. The base station 100 may provide wireless cell signal coverage and serve terminal devices in one or more cells.

Fig. 1 is a possible structure of a base station 100, where the base station 100 may include a base station antenna 101, a Transceiver (TRX) 102, and a baseband processing unit 103, where the TRX 102 is connected to an antenna port of the base station antenna 101, so that the antenna port may be used to receive a signal to be transmitted sent by the TRX 102 and a radiation unit of the base station antenna 101 radiates the signal to be transmitted, or send a received signal received by the radiation unit to the TRX 102, where the TRX 102 may be a radio remote unit (radio remote unit, RRU), and the baseband processing unit 103 may be a baseband unit (BBU).

The baseband unit may be configured to process a baseband optical signal to be sent and transmit the processed baseband optical signal to the RRU, or receive a received baseband signal sent by the RRU (that is, a baseband signal obtained by converting a received radio frequency signal received by the base station antenna 101 in a signal receiving process by the RRU) and process the received baseband optical signal, where the RRU may convert the baseband optical signal to be sent and sent by the BBU into a radio frequency signal to be sent (including performing necessary signal processing on the baseband signal, such as signal amplification, etc.), and then the RRU may send the radio frequency signal to be sent to the base station antenna 101 through an antenna port, so that the radio frequency signal radiates through the base station antenna 101, or the RRU may receive the received radio frequency signal sent by the antenna port of the base station antenna 101, convert the received radio frequency signal to the received baseband signal and send the received radio frequency signal to the BBU.

The base station antenna 101 may include an array antenna 1011, a feed network 1012, and antenna ports 1013, the array antenna 1011 may be formed of radiation units arranged in a geometric rule for receiving and/or radiating radio waves, an output end of the feed network 1012 is connected to the array antenna 1011 for feeding each radiation unit in the array antenna 1011 so that the array antenna 1011 radiates a plurality of beams, wherein different beams may cover different ranges, the feed network 1012 may include a phase shifter for changing a radiation direction of the radiation beam of the array antenna 1011, the feed network 1012 may include a vertical dimension feed network for adjusting a beam width and a vertical dimension beam direction of the beam, and a horizontal dimension feed network for performing horizontal dimension beam shaping on a transmitted signal to change the beam width, shape, and beam direction of the beam, and an input end of the feed network 1012 is connected to the antenna ports 1013 to form a transmit-receive channel, wherein each antenna port 1013 corresponds to one transmit-receive channel, and the antenna port 1013 may be connected to the TRX 102.

In some embodiments, the number of antenna ports 1013 of each base station antenna 101 may be plural, and the number of TRXs 102 may be plural, where each antenna port 1013 is connected to one TRX 102, and the baseband processing unit 103 may be connected to one or more TRXs 102.

Current communication base stations need to achieve 2G, 3G, 4G and 5G full band coverage, which requires antennas with radiating elements matching different bands. Current antennas mainly include, but are not limited to, the following structures to achieve multi-band beam scanning:

The first structure is a multi-band common-caliber antenna designed by using a coaxial (overlap-coaxial) method.

Fig. 2a is a front view of a multi-band co-aperture antenna designed using a coaxial method, and fig. 2b is a top view of a multi-band co-aperture antenna designed using a coaxial method. The low-frequency array element 2011 adopts a bowl-shaped unit, and consists of two pairs of dipoles, wherein the middle of the bowl-shaped unit is hollowed out and is used for placing the high-frequency array element 2012, the high-frequency array element 2012 in the bowl is called as a bowl-in unit, and the high-frequency array elements 2012 outside the rest bowl are called as bowl-out units. The low frequency array elements 2011 are larger in caliber than the high frequency array elements 2012. The in-bowl high frequency array element 2012 forms a dual polarized unit using conventional cross dipoles.

And a second structure is that the multi-band common-caliber antenna is designed by using an overlap-interleave method.

Fig. 2c is a front view of a multi-band co-aperture antenna designed by the flower arrangement method, and fig. 2d is a top view of the multi-band co-aperture antenna designed by the flower arrangement method. The multi-frequency antenna is formed by staggering and crossing the low-frequency array element 2021 and the high-frequency array element 2022. Fig. 2e is a schematic diagram of a feeding structure corresponding to the structure shown in fig. 2a to 2 d. The base station antenna may include a low frequency array element and a high frequency array element, where the low frequency array element is configured to receive a signal f _L sent by the low frequency feed network, and the high frequency array element is configured to receive a signal f _H sent by the high frequency feed network.

And thirdly, a multi-band common-caliber antenna designed by adopting a reflecting plate separation technology.

Fig. 2f is a schematic diagram of a multi-band co-aperture antenna designed using a reflector separation technique. The multi-band common-caliber antenna is composed of a low-frequency array element 2031 and a high-frequency array element 2032, wherein the radiation structure of the low-frequency array element 2031 is transparent to the low-frequency array element 2031 and is used as a part of the low-frequency array element 2031 and is used as the radiation ground of the high-frequency array element 2032.

And fourthly, a multi-band common-caliber antenna designed by adopting a broadband unit sharing technology.

Fig. 2g is a schematic diagram of a multi-band co-aperture antenna designed using broadband element sharing technology. The multiband common aperture antenna is composed of a broadband antenna unit 2051, and the same broadband antenna unit 2051 is shared by multiple frequency bands. Referring to fig. 2h, a schematic diagram of a feeding structure corresponding to the structure shown in fig. 2g is shown. The antenna may include a wideband antenna unit, where the wideband antenna unit is configured to receive a signal f _L sent by the low frequency feed network and a signal f _H sent by the high frequency feed network.

And fifthly, adopting a tightly coupled phased array technology to design the multi-band common-caliber antenna.

Fig. 2i is a schematic diagram of a multi-band co-aperture antenna designed using a tightly coupled phased array technique. The tightly coupled phased array includes a plurality of tightly coupled units 2061, and generally, the electrical size of each tightly coupled unit 2061 of the tightly coupled phased array is relatively small, so that in order to implement separate beamforming in different frequency bands, the input ports of each array element are respectively connected with the output ports of phase shifters in different frequencies through a frequency division network, so as to implement a common-port plane array. Referring to fig. 2j, a schematic diagram of isolation of the structure shown in fig. 2i in different frequency bands is shown, and referring to fig. 2k, a schematic diagram of a feed structure corresponding to the structure shown in fig. 2i is shown. The base station antenna may include tight coupling units 2061, where each tight coupling unit 2061 is configured to receive a signal f _L sent by the low-frequency feeding network and a signal f _H sent by the high-frequency feeding network.

The high-frequency array element and the low-frequency array element are layered three-dimensional structures, and are complex in structure and high in cost and difficult to practically apply, in the fourth structure, when broadband design is performed, wide-angle beam scanning is difficult to achieve in a bandwidth range, and when narrowband design is performed, frequency expansion cannot be performed, in the fifth structure, because the size of a tight coupling unit is smaller than that of a conventional antenna unit, the size of a feed port is larger, cost is increased due to the fact that the number of phase shifters or baseband processing modules are increased, and in addition, isolation in the low frequency band is poor.

In summary, it is still difficult to provide a multi-band common-caliber antenna that can perform multi-band expansion, especially non-integer frequency ratio in multi-band, and can realize that grating lobes are not generated in large-angle beam scanning, and simultaneously, low cost is satisfied, and isolation of each band is good.

In view of the above problems, the embodiment of the application provides a multi-band common-caliber antenna, which designs different frequency bands on a coupling array element with the same caliber, so that the antenna has a common-port structure, has good multi-band expansion capability, and can maintain good wide-angle beam scanning capability in different frequency bands. In addition, grating lobes can be avoided in the beam scanning process. In addition, the number of the feed ports is reduced due to the reconfiguration of the feed unit structure, so that the hardware cost and the power consumption are also reduced.

The multi-band common-caliber antenna provided by the embodiment of the application can meet the following conditions that the working bandwidth is covered above 10 times of frequency, and the voltage standing wave ratio of the full frequency band is smaller than 2. In the following, the structure shown in fig. 3a is described in detail, and fig. 3a is a schematic structural diagram of a multiband common aperture antenna according to the present application, where the multiband common aperture antenna 101 may include a plurality of coupling array elements 301, and each of the coupling array elements 301 is disposed on a reflective plate 302;

the frequency division multiplexing unit 303 is connected with the plurality of coupling array elements 301, the frequency division multiplexing unit 303 comprises at least one layer of frequency division multiplexing layers 304, each layer of frequency division multiplexing layers 304 comprises at least one frequency division multiplexing device 305, each frequency division multiplexing device 305 comprises an antenna port 306, at least one high-frequency port 307 and at least one low-frequency port 308, the high-frequency ports 307 form at least one high-frequency port group, and the low-frequency ports 308 form at least one low-frequency port group;

When the frequency division multiplexing unit 303 includes one layer of the frequency division multiplexing layer 304, the antenna ports 306 of the frequency division multiplexing unit 305 are connected to the coupling array element 301, the plurality of low-frequency ports 308 are connected to the low-frequency feeding unit 309, and the plurality of high-frequency ports 307 are connected to the high-frequency feeding unit 310;

When the frequency division and combining unit 303 includes at least two layers of the frequency division and combining layers 304, between every two adjacent layers, a low-frequency port 308 of an upper layer is connected to an antenna port 306 of a lower layer, the antenna port 306 of a first layer frequency division and combining unit 305 is connected to the coupling array element 301, the high-frequency port 307 of the first layer frequency division and combining unit 305 is connected to the high-frequency feeding unit 310, the low-frequency port 308 of a last layer frequency division and combining unit 305 is connected to the low-frequency feeding unit 309, and the high-frequency port 307 of the last layer frequency division and combining unit 305 is connected to the high-frequency feeding unit 310;

A low frequency feeding unit 309 for providing a low frequency signal feed;

a high frequency feeding unit 310 for feeding at least one frequency signal higher than the low frequency signal.

In some embodiments, the coupling array elements 301 form reconstruction units of different frequency bands according to different port groups, the coupling array elements 301 corresponding to the low-frequency ports 308 in the low-frequency port group together form a low-frequency reconstruction unit 311, and the coupling array elements 301 corresponding to the high-frequency ports 307 in the high-frequency port group together form a high-frequency reconstruction unit 312.

By utilizing the mode, different frequency bands can be reasonably designed in the same coupling array element 301 to form a common-port surface structure, and through flexible reconstruction of the coupling array element 301, units with different physical apertures are formed, the wide-angle beam scanning capability of each frequency band is improved, meanwhile, the cost and the complexity of the antenna can be effectively reduced, the base station antenna 101 has good spread spectrum characteristics, and the scheme for constructing the multi-frequency band common-aperture antenna with integer ratio and non-integer frequency ratio is provided. In addition, the coupling array element 301 is reconstructed, so that the isolation degree of the array antenna can meet the requirement, and the number of feed ports can be reduced when beam scanning is performed.

In some embodiments, a phase shift unit 313 is also present on the low frequency feed unit 309 and the high frequency feed unit 310;

Referring to fig. 3b, a schematic diagram of a multi-band co-aperture antenna including a phase shifting unit is shown. Each phase shifting unit 313 is configured to adjust the phase lag/lead of the electromagnetic wave radiated by the low frequency feeding unit 309 and the high frequency feeding unit 310 to a set phase corresponding to the coupled array element, where the phase shifting unit 313 is any one or more of a digital phase shifter, an analog phase shifter, and a hybrid phase shifter. And by utilizing the various phase shifting units, the phase lag/lead of the electromagnetic waves radiated by the low-frequency power supply unit and the high-frequency power supply unit is regulated to the set phase corresponding to the coupling array element so as to form beams in different directions, thereby completing beam scanning.

Specifically, the phase shift unit 313 is configured to adjust a weight coefficient of each antenna unit in the antenna array to generate a beam with directivity, which is called beamforming, and the beamforming technology is mainly based on three technical schemes of analog beamforming (analog beamforming, ABF), digital beamforming (digital beamforming, DBF), hybrid beamforming (hybrid-digital precoding beamforming, HBF), and for simplicity of explanation, the following three beamforming methods are introduced by taking one-dimensional array as an example to perform beamforming scanning to generate beamforming. It should be noted that the present application is not limited to scanning of one-dimensional beams, and the antenna array can also scan two-dimensional beams in a two-dimensional plane through reasonable coupling array element reconstruction and feed unit layout, and directional beams with directivity can be generated by adjusting the weighting coefficient of each unit in the antenna array.

Corresponding to the analog phase shifter is an analog beamforming technique, and referring to fig. 4a, a schematic diagram of beamforming of the analog phase shifter is shown. The phase shifter principle is largely divided into a phase shifter of varying physical length and a phase shifter of varying dielectric constant, the analog phase shifter part of which is usually continuously adjustable at the rear end of the antenna, which applies weights to the analog signal. At the transmitting end, the digital signals are firstly decomposed into multiple paths of analog signals by the power divider after passing through the DAC, then the multiple paths of analog signals are subjected to wave beam forming by the analog phase shifter, and at the receiving end, the analog signals received by the multiple antennas are combined and then enter the DAC through the phase shifter.

The digital beamforming technique corresponding to the digital phase shifter is shown in fig. 4b, which is a schematic diagram of the digital phase shifter. The digital phase shifter is used to apply the amplitude Xiang Quan values to the front end of the baseband signal, i.e. the transmit end is operated before entering the DAC and the receive end is operated after the ADC. The number of antenna arrays corresponds to the number of radio frequency chains (RF), namely, each RF link needs a set of independent DAC/ADC, mixer, filter and power amplifier, and when the number of ports increases, the number of radio frequency links also needs to increase.

The hybrid beamforming technique corresponds to the hybrid phase shifter, and is shown in fig. 4c, which is a beamforming schematic diagram of the hybrid phase shifter. The hybrid phase shifter integrates the characteristics of the digital phase shifter and the analog phase shifter, realizes balance on the number, cost, performance and system design complexity of the radio frequency channels, and realizes the phase encoding function through cascade conversion of the digital-to-analog converter. The number of radio frequency channels can be effectively reduced through the hybrid phase shifter, and the cost and the beam scanning performance are both considered.

In some embodiments, the frequency division combiner 305 comprises any one or more of a frequency divider, a diplexer, and a filter.

The frequency divider is not limited to a double-frequency type, and a frequency divider of a three-frequency or multi-frequency type can be used;

That is, the frequency division combiner 305 may have other frequency ports except the low frequency port 308 and the high frequency port 307, and by setting the number of interfaces of the frequency divider, the diplexer and the filter, the number of the low frequency and the high frequency ports of the frequency division combiner can be expanded to perform connection in different modes, so that the cost and the complexity of the antenna are more effectively reduced, and the antenna has good spread spectrum characteristics. The specific connection manner between the low frequency ports and the other frequency ports except the high frequency ports on the frequency division combiner 305 and the combiner structure will be known to those skilled in the art, and will not be described herein in detail.

In some embodiments, the distance d between the centers of every two adjacent coupled array elements 301 may satisfy n ₁*d≤0.5λ₁, where λ ₁ is a wavelength corresponding to the high-frequency signal input by the high-frequency feeding unit 310, and n ₁ is a positive integer, and by determining the distance d between the centers of every two adjacent coupled array elements, the grating lobes may be avoided during the beam scanning in the high-frequency band.

In some embodiments, if the maximum scan angle of the multiband common aperture antenna 101 is θ _max, the distance d between the centers of every two adjacent coupled array elements 301 may be as follows: By setting the distance d between the centers of every two adjacent coupling array elements, grating lobes can be avoided under the condition that the high-frequency band has better wide-angle beam scanning capability.

Specifically, when the beam is scanned, the interval between the low-frequency or high-frequency reconstruction units satisfies the following formula:

Lambda is the wavelength to which the signal corresponds and theta _max is the maximum scan angle of the beam scan.

Therefore, when the coupling array elements 301 are arranged, the distance D between the centers of the coupling array elements 301 needs to be set according to the distance D between the reconstruction units and the number n ₁ of the high-frequency ports in the high-frequency port group.

Alternatively, if the number of the high-frequency ports in the high-frequency port group is 1, the distance d1 between the centers of the high-frequency reconstruction units 312 is the same as the distance d between the centers of the coupling array elements 301.

If the number of the high frequency ports in the high frequency port group is m, the set distance D between the centers of the coupling array elements 301 is equal to the distance D/m between the high frequency reconstruction units 312.

In other embodiments, the number n ₂ of the low-frequency ports 308 in the low-frequency port group satisfies:

n₂*d≤0.5λ₂;

Wherein lambda ₂ is the wavelength corresponding to the low-frequency signal input by the low-frequency feed unit, d is the distance between the centers of every two adjacent coupled array elements, n ₂ is a positive integer, and the occurrence of grating lobes can be avoided in the beam scanning process of the low-frequency band by setting the number n ₂ of the low-frequency ports in the low-frequency port group because the distance d between the centers of every two adjacent coupled array elements is determined.

In other embodiments, if the maximum scan angle of the multiband common aperture antenna is θ _max, the number n ₂ of low frequency ports in the low frequency port group satisfies:

Specifically, after the coupling array elements 301 are arranged, the distance d between the centers of each coupling array element 301 is already determined, and the distance d2 between the centers of the low-frequency reconstruction units 311 is determined according to the wavelength λ ₂ corresponding to the low-frequency signal input by the low-frequency feeding unit 309 and the known d value.

The number of the low frequency ports 308 in the low frequency port group is d2, which is the interval between the centers of the low frequency reconstruction units 311. The number of low frequency ports 308 in the low frequency port group needs to satisfy:

the low frequency reconstruction units 311 are made to generate no grating lobes even when the maximum scanning angle θ _max is satisfied (the pitch between the low frequency reconstruction units 311 is smaller than )。

In some embodiments of the present application, after reconstruction, the coupling array element 301 on the multi-band co-aperture antenna can satisfy an integer frequency ratio between a high frequency and a low frequency, and beam scanning of the high frequency and the low frequency has no grating lobes, and in the following embodiments, beam scanning angles of the multi-band co-aperture antenna satisfy scanning under a maximum scanning angle of ±60°, and no grating lobes are generated.

Fig. 5a is a schematic diagram of a dual band antenna. The coupling array elements 301 in the figure are used for being connected with the antenna ports of the frequency division combiner 305, while the high-frequency port of each frequency division combiner 305 is connected with the high-frequency feeding unit 310, each two of the low-frequency ports 308 are connected with the low-frequency feeding unit 309, wherein the high frequency is f _H, the low frequency is f _L,f_H：f_L and is 2:1, the low-frequency reconstruction unit 311 is formed by reconstructing 2 coupling array elements 301, and the high-frequency reconstruction unit 312 is formed by 1 coupling array element 301, so as to realize a dual-band antenna with the frequency ratio of 2:1. The space d1 between the centers of the high-frequency reconstruction units 312 after reconstruction and the space d2 between the centers of the low-frequency reconstruction units 311 after reconstruction each satisfy the grating lobe-free condition of beam scanning.

In some embodiments of the present application, after reconstruction, the coupling array element 301 on the multiband common-caliber antenna can also satisfy the non-integer frequency ratio between the high frequency and the low frequency, and the beam scanning of the high frequency and the low frequency has no grating lobes.

Example 1, referring to fig. 5b, is a schematic diagram of a dual band antenna. The low frequency reconstruction unit 311 is reconstructed from 5 coupled array elements 301, and the high frequency reconstruction unit 312 is reconstructed from 2 coupled array elements 301, so as to realize a dual-band antenna with a frequency ratio of 2.5:1. The space d1 between the centers of the high-frequency reconstruction units 312 after reconstruction and the space d2 between the centers of the low-frequency reconstruction units 311 after reconstruction each satisfy the beam scanning grating lobe-free condition.

Example 2, referring to fig. 5c, is a schematic diagram of a dual band antenna. The low frequency reconstruction unit 311 is reconstructed from 3 coupled array elements 301, and the high frequency reconstruction unit 312 is reconstructed from 2 coupled array elements 301, so as to realize a dual-band antenna with a frequency ratio of 1.5:1. The space d1 between the centers of the high-frequency reconstruction units 312 after reconstruction and the space d2 between the centers of the low-frequency reconstruction units 311 after reconstruction each satisfy the beam scanning grating lobe-free condition.

In addition, the coupled array element reconstruction can be performed by combining the integer ratio and the non-integer ratio, so as to realize the dual-band antenna, and referring to fig. 5d, some low-frequency reconstruction units 311 are reconstructed from 4 coupled array elements 301, other low-frequency reconstruction units 311 are reconstructed from 3 coupled array elements 301, and the high-frequency reconstruction unit 312 is reconstructed from 2 coupled array elements 301. The spacing d1 between the centers of the high-frequency reconstruction units 312 after reconstruction, the spacing d21 (4 coupling array elements) and d22 (3 coupling array elements) between the centers of the low-frequency reconstruction units 311 after reconstruction all satisfy the grating lobe-free condition of beam scanning.

The reconstruction of the coupling array elements 301 only needs to satisfy the precondition of scanning without grating lobes, the adjacent coupling array elements can be arbitrarily combined within the interval range of the condition of scanning without grating lobes of the beam, and the reconstruction number of the coupling array elements is not limited in the same frequency, that is, the number of the low-frequency ports in the low-frequency port group can be arbitrarily combined and set on the premise of satisfying the condition of scanning without grating lobes, and the method is not limited.

In some embodiments, the high frequency feeding unit 310 is configured to provide at least two frequency signal feeds higher than the low frequency signal to the frequency division combiner high frequency port group. For example, in the present embodiment, the high-frequency feeding unit 310 is configured to provide two frequency signal feeds higher than the low-frequency signal, and the highest frequency signal is taken as a high-frequency signal f _H, the next highest frequency signal is taken as an intermediate-frequency signal f _M, and the low-frequency signal is taken as an example f _L. Referring to fig. 6, a schematic diagram of a tri-band antenna is shown, in which the low frequency reconstruction unit 311 is reconstructed from 4 coupling array elements 301, the intermediate frequency reconstruction unit 314 is reconstructed from 2 coupling array elements 301, and the high frequency reconstruction unit 312 is formed from 1 coupling array element 301. The space d1 between the centers of the high-frequency reconstruction units 312 after reconstruction, the space d2 between the centers of the low-frequency reconstruction units 311 after reconstruction, and the space d3 between the centers of the intermediate-frequency reconstruction units 314 after reconstruction all satisfy the grating lobe-free condition of beam scanning.

In addition, similarly, the design scheme of the application can be expanded to four-frequency-band or even N-frequency-band antennas, N is a positive integer, and multiple frequency bands share one coupling array element 301 to form a common-port surface array, so that the directional patterns of all frequency bands in the multi-frequency-band common-caliber antenna have good consistency, ultra-wideband flexible reconstruction capability and frequency expansion can be realized, and the scanning grating lobe-free condition is still met under different frequencies, so that a quite wide-angle beam scanning capability is formed, the number of active channels and the complexity of the array antenna can be effectively reduced through the reconstruction of the coupling array element 301, the feed network complexity and the antenna cost are reduced, and finally the comprehensive competitiveness of the antenna is improved.

In some embodiments, in order to improve the radiation effect of the antenna, the reconstruction method of the array antenna is not limited to the above-described reconstruction and frequency expansion of the one-dimensional coupled array element 301, and may be the reconstruction of the two-dimensional planar coupled array element 301. Fig. 7a is a schematic diagram of an area array type dual band antenna. On the array antenna, the coupled array elements are generally arranged in a two-dimensional area array type. Two rows of coupled array elements 301 are illustrated in fig. 7 a. The coupling array elements 301 are used for being connected to the antenna ports of the frequency division combiner 305, while the high frequency port of each frequency division combiner 305 is connected to the high frequency feeding unit 310, the low frequency ports 308 are grouped in groups of four, and are connected to the low frequency feeding unit 309, wherein the high frequency is f _H, the low frequency is f _L, the connection diagram of the low frequency reconstruction unit is shown in fig. 7b, the low frequency reconstruction unit 311 is reconstructed from 2×2 coupling array elements 301, the connection diagram of the high frequency reconstruction unit is shown in fig. 7c, and the high frequency reconstruction unit 312 is formed from 1 coupling array element 301. The center-to-center distance d1 of the high-frequency reconstruction unit 312 after reconstruction and the center-to-center distance d2 of the low-frequency reconstruction unit 311 after reconstruction each satisfy the grating lobe-free condition of beam scanning. The number of the channels of the feed port is effectively reduced, so that the cost is reduced.

In addition, the above-mentioned reconstruction method of the array antenna is not limited to the above-mentioned one-dimensional and two-dimensional reconstruction, and the array antenna may be of a conformal-plane antenna array type, and referring to fig. 7d, which is a schematic diagram of an antenna of a conformal-plane antenna array type, fig. 7e is a schematic diagram of feeding an antenna of a conformal-plane antenna array type, and the reconstruction method of the coupling array element on the specific conformal plane is based on the same concept as the above-mentioned reconstruction method, and will not be repeated here.

In some embodiments, array element reconstruction may be performed on a single polarized planar array, where the reconstruction of a single polarization may include the following:

In a first embodiment, referring to fig. 7f, a planar array is schematically formed by reconstructing a coupling array element in a horizontal direction. In the left diagram, the low-frequency reconstruction unit 311 is horizontally reconstructed by 2 coupling array elements 301 in the horizontal direction, and the high-frequency reconstruction unit 312 is formed by 1 coupling array element 301, so as to realize a dual-band antenna reconstructed in the horizontal direction. In the middle diagram, the low-frequency reconstruction unit 311 is vertically reconstructed by 2 coupling array elements 301 in the horizontal direction, and the high-frequency reconstruction unit 312 is formed by 1 coupling array element 301, so as to realize the vertical direction reconstruction of the dual-band antenna. In the right diagram, the low-frequency reconstruction unit 311 is vertically and horizontally reconstructed by 2×2 coupling array elements 301 in the horizontal direction, and the high-frequency reconstruction unit 312 is formed by 1 coupling array element 301, so as to realize the vertical and horizontal direction reconstruction of the dual-band antenna.

Mode two, referring to fig. 7g, is a schematic diagram of a planar array formed by reconstructing a coupling array element in a vertical direction. In the left diagram, the low-frequency reconstruction unit 311 is horizontally reconstructed by 2 coupling array elements 301 in the vertical direction, and the high-frequency reconstruction unit 312 is formed by 1 coupling array element 301, so as to realize a dual-band antenna reconstructed in the horizontal direction. In the middle diagram, the low-frequency reconstruction unit 311 is vertically reconstructed by 2 coupling array elements 301 in the vertical direction, and the high-frequency reconstruction unit 312 is formed by 1 coupling array element 301, so as to realize the dual-band antenna reconstructed in the vertical direction. In the right diagram, the low-frequency reconstruction unit 311 is vertically and horizontally reconstructed by 2 x2 coupling array elements 301 in the vertical direction, and the high-frequency reconstruction unit 312 is formed by 1 coupling array element 301, so as to realize a dual-band antenna reconstructed in the vertical and horizontal directions.

In a third mode, referring to fig. 7h, a planar array schematic diagram of a non-integer ratio formed by reconstructing a coupling array element in a horizontal direction is shown. In the left diagram, the low-frequency reconstruction unit 311 is horizontally reconstructed from 3 horizontal coupling array elements 301, and the high-frequency reconstruction unit 312 is horizontally reconstructed from 2 horizontal coupling array elements 301, so as to realize a horizontally reconstructed dual-band antenna. In the right diagram, the low-frequency reconstruction unit 311 is vertically and horizontally reconstructed by 3*3 coupling array elements 301 in the horizontal direction, and the high-frequency reconstruction unit 312 is vertically and horizontally reconstructed by 2 coupling array elements 301 in the horizontal direction, so as to realize a vertically and horizontally reconstructed dual-band antenna.

Mode four, referring to fig. 7i, is a schematic diagram of a three-band planar array formed by reconstructing coupling array elements in a horizontal direction. In the left diagram, the low-frequency reconstruction unit 311 is horizontally reconstructed from 4 horizontal coupling array elements 301, the intermediate-frequency reconstruction unit 314 is horizontally reconstructed from 2 horizontal coupling array elements 301, and the high-frequency reconstruction unit 312 is formed from 1 horizontal coupling array element 301, so as to realize a horizontally reconstructed tri-band antenna. In the middle diagram, the low-frequency reconstruction unit 311 is horizontally and vertically reconstructed from 2 x 4 horizontal coupling array elements 301, the intermediate-frequency reconstruction unit 314 is horizontally and vertically reconstructed from 2 x2 horizontal coupling array elements 301, and the high-frequency reconstruction unit 312 is formed from 1 horizontal coupling array element 301, so as to realize a vertically and horizontally reconstructed tri-band antenna. In the right diagram, the low-frequency reconstruction unit 311 is horizontally and vertically reconstructed by 4*4 horizontal coupling array elements 301, the intermediate-frequency reconstruction unit 314 is horizontally and vertically reconstructed by 2 x2 horizontal coupling array elements 301, and the high-frequency reconstruction unit 312 is formed by1 horizontal coupling array element 301, so as to realize a vertically and horizontally reconstructed tri-band antenna.

After the coupling array element 301 is periodically reconfigured, the planar array after reconfiguration belongs to a periodic array, while the coupling array element 301 is non-periodically reconfigured, and the array after reconfiguration is equivalent to a sparse array. Specifically, flexible arrangement can be performed according to the requirements of the array antenna. Alternatively, the coupling array elements 301 may be arranged in a periodic sequence or an aperiodic sequence on the planar array:

Mode one, the planar array is arranged periodically, and referring to fig. 8a, a schematic diagram of periodically arranged array elements is shown. And (3) reconstructing one frequency band by using the coupling array element 301 (other frequency bands are similar), configuring different excitation assignments for the ports connected with the reconstructed coupling array element 301, and finally realizing the directional diagram characteristic of specific performance, wherein the left diagram is a reconstruction schematic diagram of the coupling array element 301, the middle diagram is a distribution schematic diagram of the reconstructed equivalent antenna unit, the right diagram is an excitation amplitude distribution schematic diagram, and different excitation amplitude values are represented by different patterns.

In the second mode, the planar arrays are arranged in a non-periodic manner, as shown in fig. 8b, the left graph is a schematic diagram of reconstruction of the coupled array elements 301, the middle graph is a schematic diagram of distribution of the reconstructed equivalent antenna units, and the right graph is a schematic diagram of excitation amplitude distribution.

In the third mode, a dummy area may be configured on the planar array to implement a sparse array, referring to fig. 8c, each reconstruction unit may be reconstructed from the same number of coupled array elements 301 or different numbers of coupled array elements 301, for a sparse array antenna, the performance of the array may be optimized by an algorithm, a left graph is shown as a reconstruction schematic diagram of the coupled array elements 301, a dummy shown by a dashed frame may be configured in the planar array, and a feeding configuration is not performed on the dummy, thereby implementing an equivalent sparse array, a middle graph is a reconstructed equivalent array distribution schematic diagram, and a right graph is a magnitude distribution schematic diagram of the equivalent array.

In some embodiments, the coupling element 301 comprises at least one dipole element;

The dipole array element is parallel to the polarization direction of the coupling array element 301, and coupling capacitors are present at two sides of the end of the dipole array element, so that the coupling array element has at least one polarization direction by setting the direction of the dipole array element, so as to form more polarization types.

In the above embodiment, the coupling array elements 301 are provided in all monopole directions, and optionally, the multi-band co-aperture antenna may also support multi-polarization directions, and by setting dipole array elements in an orthogonal manner, the coupling array elements may have dual polarization characteristics in different directions such as vertical and horizontal directions, ±45°, and so on.

When the coupling array element 301 is designed with dual polarization, when the coupling array element 301 includes two dipole array elements, the dipole array elements are orthogonally arranged, and the coupling array element 301 includes but is not limited to orthogonally arranged in the following manner:

In the first embodiment, two dipole elements are designed in the vertical and horizontal directions, as shown in fig. 9a, wherein the low-frequency reconstruction unit 311 in the left side is formed by horizontally reconstructing 2 coupling elements 301 including the dipole elements in the vertical and horizontal directions, and the high-frequency reconstruction unit 312 includes the coupling elements 301 including the dipole elements in the vertical and horizontal directions. In the middle diagram, the low-frequency reconstruction unit 311 is vertically reconstructed from 2 coupling array elements 301 including dipole array elements in the vertical and horizontal directions, and the high-frequency reconstruction unit 312 includes coupling array elements 301 including dipole array elements in the vertical and horizontal directions. In the right side, the low frequency reconstruction unit 311 is vertically and horizontally reconstructed from 2×2 coupling elements 301 including dipole elements in the vertical and horizontal directions, and the high frequency reconstruction unit 312 is formed from 1 coupling element 301 including dipole elements in the vertical and horizontal directions.

In the second mode, two dipole elements are designed in the ±45° direction, as shown in fig. 9b, wherein the low-frequency reconstruction unit 311 in the left side view is horizontally reconstructed from 2 coupling elements 301 including the ±45° dipole elements, and the high-frequency reconstruction unit 312 is formed from 1 coupling element 301 including the ±45° dipole elements. In the middle diagram, the low-frequency reconstruction unit 311 is vertically reconstructed from 2 coupling array elements 301 including ±45° direction dipole array elements, and the high-frequency reconstruction unit 312 is formed from 1 coupling array element 301 including ±45° direction dipole array elements. In the right side diagram, the low frequency reconstruction unit 311 is vertically and horizontally reconstructed from 2×2 coupling array elements 301 including ±45° direction dipole array elements, and the high frequency reconstruction unit 312 is formed from 1±45° direction dipole array element coupling array elements 301.

In addition, fig. 10 is a schematic diagram of a four-Band monopole planar array, where the schematic diagram includes 12×12 coupling array elements 301, the physical apertures of the coupling array elements 301 are 19mm×19mm, and the array element spacing is also 19mm, and the co-planar array antenna includes Band3, band41, band42 and LAA frequency Band, where the standing wave bandwidth of the four-Band antenna can cover 1.5-6 ghz. And finally, each frequency band is kept with reasonable channel quantity, the quantity of antenna feed ports is reduced, the cost is saved, and the comprehensive competitiveness of the antenna is improved. Specifically, according to the array scanning grating lobe-free formula, the distance between the coupling array elements is about 0.5λ _LAA, if the distance between the coupling array elements 301 is set to be 0.5λ _LAA, the frequency of the LAA frequency Band is highest, the coupling array elements 301 are antenna elements of the LAA frequency Band, 3.5G (Band 42) can use 4 coupling array elements 301 at most for reconstruction, 2.6G (Band 41) can use 9 coupling array elements 301 at most for reconstruction, 1.7G (Band 3) can use 16 coupling array elements 301 at most for reconstruction, the number of feed ports can be reduced by using the antenna structure, the cost is reduced, and reconstruction units of different frequency bands composed of different antenna elements can be flexibly configured within the maximum number range of reconfigurable coupling array elements.

Alternatively, referring to table 1 below, the lower the frequency, the more the number of coupling array elements available for reconstruction, so the more flexible the reconstruction mode, the dark color part in table 1 is the reconstruction scale of the coupling array elements with different frequency bands, and when the distance between the reconstructed antenna units after reconstruction is not more than about 0.5 times of the wavelength of the corresponding frequency band, the grating lobe-free scanning with the beam scanning angle reaching ±60 degrees can be satisfied. In addition, the number of the reconfigurable antenna units existing on the array antenna is different due to different reconfiguration modes, wherein for the 12×12-scale array antenna, at least 144 reconfigurable antenna units of the LAA frequency Band can be designed on the array antenna, at least 36 reconfigurable antenna units of the Band42 frequency Band can be designed on the array antenna, at least 16 reconfigurable antenna units of the Band42 frequency Band can be designed on the array antenna, and at least 9 reconfigurable antenna units of the Band3 frequency Band can be designed on the array antenna. Referring to table 2 below, compared with the traditional four-frequency-band antenna array, the four-frequency-band antenna provided by the application can save the number of feed ports on different frequency bands and reduce the cost.

The number of the feed ports of Band3 frequency Band can be saved (144-9), the number of the feed ports of Band41 frequency Band can be saved (144-16), and the number of the feed ports of Band42 frequency Band can be saved (144-36), so that the number of the feed ports is reduced compared with the traditional scheme for a four-frequency Band antenna with 12×12 coupling array element scale: Thereby effectively reducing the complexity of the antenna and the number of beam forming feed port channels. The large-scale sparse antenna array can be reconstructed by flexibly adjusting the number of the coupling array elements of each reconstruction unit, and the antenna array with higher performance or special requirements is realized.

TABLE 1

TABLE 2

The multi-band common-caliber antenna provided by the application is used for reconstructing the coupling array elements based on the tightly-coupled phased array technology, and the coupling array elements are flexibly reconstructed to the physical apertures of units in different frequency bands, so that the multi-band common-caliber antenna array is realized, the scanning capability of beams in different frequency ratios in common aperture and in wide angles in each frequency band can be realized, the cost and complexity of the antenna can be effectively reduced, the good multi-frequency expansion capability can be realized, the scheme of integer and non-integer frequency ratios can be further constructed, the port isolation between the reconstructed units is improved by at least 6dB compared with that of the conventional tightly-coupled units, and the same coupling array elements are shared due to the design of the multi-band common-caliber antenna in common aperture, so that the antenna has good manufacturability, has good directional diagram consistency in each frequency band, can keep a corresponding beam scanning angle in different frequency bands, the problem of grating lobes caused by overlarge spacing is solved, the number of feed ports is further reduced, and the cost is reduced.

In some embodiments, the multi-band co-aperture antenna of the present application may also be applied to the design of a reflective array antenna. Referring to fig. 11, a schematic diagram of a reflective array antenna is shown, where the reflective array antenna is composed of a feed source 1101 and a reflective surface 1102, the reflective surface 1102 is generally in a planar structure, and the planar arrangement of units irradiated by the feed source 1101 makes the antenna have parabolic characteristics, and the main principle is that by adjusting the sizes of the unit structures on the reflective surface 1102 at different positions, the reflective surface 1102 has different values of phase delays, and by precise design, the beam focusing and pointing of the antenna can be regulated. But the traditional reflective array antenna has narrow-band characteristic, and the bandwidth of the reflective array antenna formed by the traditional microstrip patch units is less than 5 percent due to the fact that the spatial phase delay difference changes along with the frequency, and the same size is changed, so that the defect of high gain bandwidth is difficult to maintain.

The reflecting surface 1102 may be configured as a smart reflecting surface (INTELLIGENT REFLECTOR SURFACE, IRS), as shown in fig. 12, the smart reflecting surface IRS includes:

The application relates to a multi-band common-caliber antenna design, which comprises a reflecting unit 1204, a copper plate 1203, a PIN diode, a variable resistance load and a variable resistance load, wherein the IRS controller 1201 is used for receiving reflection amplitude/phase shift information, the control circuit board 1202 is triggered by the IRS controller 1201 and is used for adjusting the reflection amplitude/phase shift of each reflecting unit 1204, the copper plate 1203 is used for avoiding signal energy leakage, the PIN diode is embedded in the reflecting unit 1204, the bias voltage is controlled through a DC feeder line, the PIN diode is switched between an on state and an off state, pi phase difference is generated, in order to effectively control the reflection amplitude, a variable resistance load can be applied in the design of the reflecting unit 1204, different parts of incident signal energy are consumed by changing resistance values in each reflecting unit 1204, and therefore controllable reflection amplitude is realized in [0,1], but the bandwidth of the intelligent reflecting surface is limited by a patch unit form, the bandwidth of the multi-band common-caliber antenna design is narrow, and each reflecting unit 1204 of the reflecting surface can be equivalent to a coupling array element. Referring to fig. 13, a schematic diagram of a reflection unit is shown, and a diode or a MEMS (micro-electro-MECHANICAL SYSTEM) switch or the like is loaded on each patch unit to implement reflection beam modulation of the operating frequency. After the patch unit 1301 receives the load and performs reconstruction and combination, a control diode 1302 is loaded to equivalently expand the unit physical aperture of the reflective array antenna, so that new frequency is added on the reflective surface, the characteristic of the multi-frequency shared aperture reflective surface is realized, and the bandwidth expansion of the reflective array antenna is also realized. Or the reconstruction unit can be loaded with an absorption resistor 1303, wave absorption characteristics are generated in a specific frequency band, a radar scattering interface is reduced, stealth characteristics of the reflection array are realized, and safety is improved.

In addition, the embodiment of the application also provides communication equipment which comprises the multi-band common-caliber antenna. The design ensures that the communication equipment comprising the multi-band common-caliber antenna has good multi-band expansion capability and can keep good wide-angle beam scanning capability in different frequency bands. In addition, grating lobes can be avoided in the beam scanning process. In addition, since the number of the feeding ports is reduced due to the reconfiguration of the feeding unit structure, hardware overhead and power consumption can also be reduced.

According to the scheme, the multi-band common-caliber antenna and the communication equipment are adopted, the coupling array elements are reconstructed based on the tight coupling phased array technology, the coupling array elements are flexibly reconstructed to the physical apertures of units in different frequency bands, the multi-band common-port type antenna array is realized, the beam scanning capability of different frequency ratios of the common aperture and the wide angles of each frequency band can be realized, the antenna cost and complexity can be effectively reduced, the good multi-frequency expansion capability can be realized, the scheme of integer and non-integer frequency ratio can be further constructed, the port isolation between the reconstructed units is improved by at least 6dB compared with that of the traditional tight coupling units, the multi-band common-caliber antenna is designed to be a common-port surface, the same coupling array elements are shared, good manufacturability is realized, the directional diagram consistency of each frequency band is good, the corresponding beam scanning angle can be kept in different frequency bands, the problem of grating lobes caused by overlarge spacing is solved, the number of feed ports is further reduced, and the cost is reduced.

It will be appreciated by those skilled in the art that embodiments of the present application may be provided as a method, system, or computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.

The present application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems) and computer program products according to the application. It will be understood that each flow and/or block of the flowchart illustrations and/or block diagrams, and combinations of flows and/or blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

It will be apparent to those skilled in the art that various modifications and variations can be made to the present application without departing from the scope of the application. Thus, it is intended that the present application also include such modifications and alterations insofar as they come within the scope of the appended claims or the equivalents thereof.

Claims

1. The multi-band common-caliber antenna is characterized by comprising a plurality of coupling array elements, a frequency division and combination unit, a low-frequency feed unit and a high-frequency feed unit, wherein:

Each coupling array element is arranged on the reflecting plate;

The frequency division and combination unit is connected with the plurality of coupling array elements, the frequency division and combination unit comprises at least one layer of frequency division and combination layer, each layer of frequency division and combination layer comprises at least one frequency division and combination device, each frequency division and combination device comprises an antenna port, a plurality of high-frequency ports and a plurality of low-frequency ports, the high-frequency ports form at least one high-frequency port group, and the low-frequency ports form at least one low-frequency port group;

A low frequency feeding unit for providing a low frequency signal feed;

2. The multi-band co-aperture antenna of claim 1, wherein the coupling array elements are grouped according to different ports to form reconstruction units of different frequency bands, the coupling array elements corresponding to the low frequency ports in the low frequency port group together form a low frequency reconstruction unit, and the coupling array elements corresponding to the high frequency ports in the high frequency port group together form a high frequency reconstruction unit.

3. A multiband common aperture antenna according to claim 1 or 2, wherein the distance d between the centers of every adjacent two coupled elements is such that:

n₁*d≤0.5λ₁;

4. A multi-band co-aperture antenna as claimed in claim 3, wherein if the maximum scan angle of the multi-band co-aperture antenna is θ _max, the distance d between the centers of every two adjacent coupled array elements is:

5. the multi-band co-aperture antenna of any of claims 1-4 wherein the number n ₂ of the low-frequency ports in the low-frequency port group satisfies:

n₂*d≤0.5λ₂;

6. The multi-band co-aperture antenna of claim 5 wherein the number n ₂ of the low frequency ports in the low frequency port group satisfies:

7. The multi-band co-aperture antenna according to any one of claims 1-6, wherein phase shifting units are further provided on the low frequency feeding unit and the high frequency feeding unit;

Each phase shifting unit is used for adjusting the phase lag/lead of the electromagnetic wave radiated by the low-frequency power supply unit and the high-frequency power supply unit to the set phase corresponding to the coupling array element, and the phase shifting unit is any one or more of a digital phase shifter, an analog phase shifter and a hybrid phase shifter.

8. The multi-band co-aperture antenna of any of claims 1-7 wherein the coupling element comprises at least one dipole element, the dipole element being parallel to a polarization direction of the coupling element, and coupling capacitors being present on opposite sides of an end of the dipole element.

9. The multi-band co-aperture antenna of claim 8, wherein when the coupling element comprises two dipole elements, the dipole elements are orthogonally disposed.

10. The multi-band co-aperture antenna of any one of claims 1-9, wherein the frequency division combiner comprises any one or more of a frequency divider, a duplexer, and a filter.

11. A communications device comprising a multi-band co-aperture antenna according to any one of claims 1 to 10.