Phase shifter feed network based on multi-cavity coaxial transmission line and base station antenna thereof

Abstract

The invention provides a phase shifter feed network based on a multi-cavity coaxial transmission line and a base station antenna thereof, and relates to the field of communication antennae, the phase shifter feed network comprises a phase shifter, a multi-cavity metal profile and N + 1 signal transmission lines arranged in the multi-cavity metal profile; the multi-cavity metal profile is an integrally-formed part, a plurality of cylindrical cavities parallel to one another are formed in the multi-cavity metal profile, and the cylindrical cavities penetrate through the multi-cavity metal profile in the Y-axis direction and are sequentially arranged side by side in the X-axis direction. Each signal transmission line comprises a plurality of sections of metal tubes which are connected in sequence, and the plurality of sections of metal tubes are distributed in the same or different cylindrical cavities; each section of metal pipe is supported in the cylindrical cavity through a supporting connecting piece and is coaxial with the cylindrical cavity. According to the invention, the flexibility and applicability of the feed network are improved, and the production cost and transmission loss of the antenna feed network are reduced.

Description

Technical Field

[0001] The present invention relates to the field of communication antennas, and particularly to a phase shifter feeding network based on a multi-cavity coaxial transmission line and a base station antenna thereof. Background Art

[0002] The feeding network is an important component in a base station antenna. It is connected between the antenna port and the radiation element array to form a path for RF signal transmission, and realizes functions such as impedance matching, amplitude and phase distribution. The feeding network is closely related to the performance of the base station antenna. Its main function is to transmit the high-frequency current from the transmitter to the radiation element, or transmit the high-frequency current from the radiation element to the transmitter.

[0003] In existing feeding networks, the main transmission methods of feeding signals are stripline transmission and microstrip line transmission. Among them, the feeding network based on stripline transmission usually includes an aluminum profile cavity with a rectangular cross-section and a PCB board disposed in the aluminum profile cavity. Circuit structures such as a power divider and a phase shifter formed by a stripline network are printed on the PCB board; by grounding the aluminum profile cavity, its upper and lower side walls are equivalent to two parallel ground planes, thereby realizing stripline transmission. The feeding network based on microstrip line transmission is mainly composed of a PCB board. Circuit structures such as a power divider and a phase shifter formed by a microstrip line network are printed on one side of the PCB board, and a metal floor is printed on the other side of the PCB board.

[0004] However, the feeding networks using these two transmission methods all have some defects more or less.

[0005] First, both feeding networks have the problems of excessive customization and insufficient flexibility. Specifically, both striplines and microstrip lines need to be printed on the PCB board, making the distribution and design indexes of the feeding network relatively fixed and difficult to reuse; when the application scenario and design requirements of the feeding network change, it is necessary to redesign and print different PCB boards.

[0006] Second, both feeding networks have the problem of relatively high production costs. On the one hand, the cost of the PCB board used for printing striplines and microstrip lines is relatively high, resulting in a high overall production cost of related structures. On the other hand, when wiring the feeding network based on striplines, welding and electroplating need to be performed on the aluminum profile cavity, increasing the labor cost and process cost, and the manual participation is relatively high, which is not conducive to automated production.

[0007] Thirdly, there are varying degrees of transmission losses in both types of feeding networks. On the one hand, in the feeding network based on stripline transmission, the main mode of stripline transmission is the TEM (Transverse Electromagnetic) mode, and the directions of its electric field and magnetic field are both perpendicular to the wave propagation direction. Since all striplines are encapsulated in the same closed aluminum profile cavity through the PCB board, the electromagnetic waves generated by each stripline during signal transmission oscillate repeatedly between the upper and lower ground planes and affect each other, resulting in inevitable interference between each branch, introducing transmission losses and reducing transmission efficiency. On the other hand, in the feeding network based on microstrip line transmission, the main mode of microstrip line transmission is the quasi-TEM mode, and its electric field and magnetic field are mainly transverse, but there are small longitudinal components. This causes surface waves to form at the edges of the microstrip line during signal transmission, resulting in partial energy radiation and radiation losses. In addition, since the main mode of the coaxial cable used to introduce external feeding signals is the TEM mode, there is a conversion of different transmission modes at the connection between the coaxial cable and the microstrip line, which leads to transmission discontinuity and thus generates discontinuity losses. The more times of conversion between different transmission modes, the greater the losses generated.

[0008] It can be seen from this that the feeding networks in the prior art have the defects of poor flexibility, high cost, and large losses, and need to be improved and perfected. Summary of the Invention

[0009] The purpose of the present invention is to provide a phase shifter feeding network based on a multi-cavity coaxial transmission line and its base station antenna for the problems existing in the prior art, so as to improve the flexibility and applicability of the feeding network and reduce the production cost and transmission losses of the antenna feeding network.

[0010] To achieve the above purpose, the present invention adopts the following technical solutions: A phase shifter feeding network based on a multi-cavity coaxial transmission line includes a phase shifter, a multi-cavity metal profile, and N + 1 signal transmission lines arranged in the multi-cavity metal profile; The multi-cavity metal profile is an integrally formed part, and the interior of the multi-cavity metal profile is provided with a plurality of cylindrical cavities that are parallel to each other. The plurality of cylindrical cavities penetrate the multi-cavity metal profile along the Y-axis direction and are arranged side by side in sequence along the X-axis direction; Each signal transmission line includes a plurality of metal tubes connected in sequence. The plurality of metal tubes are distributed in the same or different cylindrical cavities; among them, each metal tube is supported in the cylindrical cavity by a support connecting piece and is coaxially arranged with the cylindrical cavity; the support connecting piece is made of an insulating medium, so that the metal tube is not in contact with and not electrically connected to the multi-cavity metal profile; the multi-cavity metal profile is grounded, so that the metal tube can transmit the feeding signal in the cylindrical cavity in the TEM mode; The phase shifter is fixedly connected to the bottom surface of the multi-cavity metal profile. The phase shifter has one input end and N output ends, and the N + 1 signal transmission lines are respectively connected to one input end and N output ends of the phase shifter in one-to-one correspondence.

[0011] Further, a feeding probe is provided at each input end and output end of the phase shifter. The phase shifter is connected to the signal transmission line in the cylindrical cavity by passing the feeding probe through the side wall of the multi-cavity metal profile. The input end of the phase shifter is connected to an external feeding signal source through the signal transmission line, and the output ends of the phase shifter are respectively connected to the antenna units through the signal transmission lines to distribute feeding signals with phase differences to the antenna units.

[0012] Further, in a signal transmission line, several sections of metal tubes included are sequentially connected by a bridging member or a connecting column; among them, two sections of metal tubes distributed in different cylindrical cavities are connected by a bridging member, and two sections of metal tubes distributed in the same cylindrical cavity are connected by a connecting column.

[0013] Further, the connecting column is made of the same material as the metal tube; when two sections of metal tubes arranged in the same cylindrical cavity are connected by a connecting column, the outer diameters of both ends of the connecting column respectively match the inner diameters of the two sections of metal tubes to be connected, and both ends of the connecting column are respectively inserted into the ends of the two sections of metal tubes to connect and conduct the two sections of metal tubes to each other.

[0014] Further, the bridging member includes a bridging plug and a metal conductive sheet fixed in the bridging plug; a bridging window hole communicating with the outside is provided on the top surface or bottom surface side wall of the cylindrical cavity; when two sections of metal tubes distributed in two different cylindrical cavities are connected by a bridging member, the bridging plug of the bridging member is plugged into the bridging window holes connecting the two cylindrical cavities from the outside of the multi-cavity metal profile, so that the metal conductive sheet is respectively in contact with the two sections of metal tubes at the bridging window holes of the two cylindrical cavities to connect and conduct the two sections of metal tubes to each other.

[0015] Further, the phase shifter includes a main circuit board, a coupling sliding piece, a fixed pressing piece, a rotating shaft and a transmission rack; The main circuit board, the coupling sliding piece and the fixed pressing piece are sequentially stacked on the bottom surface of the multi-cavity metal profile; the main circuit board is fixedly connected to the multi-cavity metal profile, the rotating shaft sequentially penetrates through the multi-cavity metal profile, the main circuit board, the coupling sliding piece and the fixed pressing piece along the Z-axis direction, the rotating shaft is rotatably connected to the main circuit board, and is fixedly connected to the coupling sliding piece and the fixed pressing piece, so that the coupling sliding piece and the fixed pressing piece can rotate relative to the main circuit board; The transmission rack is slidably and limitedly connected to the bottom surface of the multi-cavity metal profile through a limiting connecting piece. The transmission rack is in gear transmission connection with the fixed pressing piece and is used to adjust the rotation angle of the fixed pressing piece. On one side of the main circuit board facing the coupling sliding piece, a transmission microstrip line and several phase delay microstrip lines are printed. One end of the transmission microstrip line is the input end of the phase shifter, and the other end of the transmission microstrip line is an output end of the phase shifter. The several phase delay microstrip lines are arranged in parallel with each other. A phase adjustment section in an arc shape is provided in the middle of each phase delay microstrip line, and the phase adjustment sections are all centered on the rotating shaft. The two ends of each phase delay microstrip line are respectively two output ends of the phase shifter. On one side of the coupling sliding piece facing the main circuit board, a coupling microstrip line is printed. The fixed pressing piece is fixedly connected to the coupling sliding piece and presses the coupling sliding piece against the main circuit board, so that the coupling microstrip line on the coupling sliding piece is coupled with the transmission microstrip line and the phase delay microstrip lines on the main circuit board at the same time, so as to conduct the input end of the phase shifter to each output end. When the transmission rack drives the fixed pressing piece to rotate, it synchronously drives the coupling sliding piece to rotate, so that the coupling microstrip line on the coupling sliding piece slides synchronously in the circumferential direction within the phase adjustment sections of each phase delay microstrip line, so as to adjust the phase difference between the input end and each output end of the phase shifter.

[0016] Further, the multi-cavity metal profile is an aluminum profile and is made by an integrated pultrusion process.

[0017] Further, the metal tube is a metal copper tube.

[0018] A single-polarization base station antenna includes the phase shifter feeding network described above, and also includes a radio frequency connector and N single-polarization antenna elements. The radio frequency connector is fixedly connected to the bottom surface of the multi-cavity metal profile and is used to connect to an external coaxial cable to introduce a feeding signal. The N single-polarization antenna elements are arranged in an array and fixedly connected to the middle of the top surface of the multi-cavity metal profile. In the phase shifter feeding network, the input end of the phase shifter is connected to the radio frequency connector through a signal transmission line to receive the feeding signal. The N output ends of the phase shifter are respectively connected to the N single-polarization antenna elements in one-to-one correspondence through signal transmission lines to distribute feeding signals with a phase difference to the N single-polarization antenna elements. Feeding probes are respectively provided at the top of the radio frequency connector and the bottom of the single-polarization antenna element. The radio frequency connector and the single-polarization antenna element are respectively connected to the phase shifter feeding network through the feeding probes passing through the side wall of the multi-cavity metal profile.

[0019] A dual-polarized base station antenna includes the phase shifter feeding network described above, and also includes a first RF connector, a second RF connector, and N dual-polarized antenna units; There are two phase shifter feeding networks, namely a first phase shifter feeding network and a second phase shifter feeding network; the first phase shifter feeding network and the second phase shifter feeding network are symmetrically arranged and share the same multi-cavity metal profile; The first RF connector and the second RF connector are fixedly connected to the bottom surface of the multi-cavity metal profile. The first RF connector is used to connect to an external first coaxial cable to introduce a first polarization feeding signal, and the second RF connector is used to connect to an external second coaxial cable to introduce a second polarization feeding signal; the N dual-polarized antenna units are arranged in an array and fixedly connected to the middle of the top surface of the multi-cavity metal profile; In the first phase shifter feeding network, the input end of the phase shifter is connected to the first RF connector through a signal transmission line to receive the first polarization feeding signal; the N output ends of the phase shifter are respectively connected to the N dual-polarized antenna units through signal transmission lines in one-to-one correspondence to distribute the first polarization feeding signals with a phase difference to the N dual-polarized antenna units; In the second phase shifter feeding network, the input end of the phase shifter is connected to the second RF connector through a signal transmission line to receive the second polarization feeding signal; the N output ends of the phase shifter are respectively connected to the N dual-polarized antenna units through signal transmission lines in one-to-one correspondence to distribute the second polarization feeding signals with a phase difference to the N dual-polarized antenna units; Feeding probes are respectively provided at the tops of the first RF connector and the second RF connector. The first RF connector is connected to the first phase shifter feeding network through the feeding probe, and the second RF connector is connected to the second phase shifter feeding network through the feeding probe; A first polarization feeding probe and a second polarization feeding probe are respectively provided at the bottom of each dual-polarized antenna unit; the N dual-polarized antenna units are respectively connected to the first phase shifter feeding network through the first polarization feeding probes, and the N dual-polarized antenna units are respectively connected to the second phase shifter feeding network through the second polarization feeding probes.

[0020] A phase shifter feeding network based on a multi-cavity coaxial transmission line provided by the present invention forms a signal transmission line through a metal tube arranged in a multi-cavity metal profile, does not require the use of a PCB board, and does not require welding and electroplating during wiring of the multi-cavity metal profile, which not only reduces the production cost but also improves the intermodulation stability of the circuit; at the same time, it is more suitable for automated production and improves the production efficiency.

[0021] In each signal transmission line of the present invention, the cylindrical cavity of the multi-cavity metal profile is used as the outer conductor, and the metal tube is used as the inner conductor, realizing a transmission mode with the TEM mode as the main mode, reducing the radiation loss of the feeding signal during transmission, and being almost unaffected by external signals. In addition, since each cylindrical cavity is completely isolated from each other, the coupling between the cylindrical cavities is zero, which can effectively avoid the mutual influence of the electromagnetic waves generated by each signal transmission line, reduce the transmission loss of the feeding signal, and greatly improve the transmission efficiency.

[0022] On this basis, the present invention connects multiple metal tubes in sequence through connecting columns and bridging members to form multiple independent signal transmission lines, providing sufficient freedom for the arrangement of the signal transmission lines. Different lengths of metal tubes can be combined with connecting columns and bridging members to flexibly build signal transmission lines with different orientations, which can better meet the design requirements of different engineering applications, and has sufficient flexibility and applicability, with broad application prospects.

[0023] The antenna base station of the present invention adopts a modular design method. The phase shifter, RF connector, and antenna unit are all quickly connected to the signal transmission line through feeding probes, enabling convenient, fast installation, construction, disassembly, and replacement, and can flexibly adapt to the design requirements of different base station antenna systems, with broad applicability.

[0024] In summary, the phase shifter feeding network and its base station antenna based on multi-cavity coaxial transmission lines provided by the present invention improve the flexibility and applicability of the feeding network, and reduce the production cost and transmission loss of the antenna feeding network. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 FIG. is an exploded view of a phase shifter feeding network based on multi-cavity coaxial transmission lines provided in Embodiment 1 of the present invention.

[0026] Figure 2 FIG. is a schematic structural diagram of the multi-cavity metal profile in Embodiment 1 of the present invention.

[0027] Figure 3 FIG. is a schematic structural diagram of the first signal transmission line in Embodiment 1 of the present invention.

[0028] Figure 4 FIG. is a schematic structural diagram of the second signal transmission line in Embodiment 1 of the present invention.

[0029] Figure 5 FIG. is an exploded view of the phase shifter in Embodiment 1 of the present invention.

[0030] Figure 6 FIG. is another exploded view of the phase shifter in Embodiment 1 of the present invention.

[0031] Figure 7It is a schematic diagram of the overall structure of a dual-polarized antenna base station provided in the second embodiment of the present invention.

[0032] Figure 8 It is a schematic side view of a dual-polarized antenna base station provided in the second embodiment of the present invention.

[0033] Figure 9 It is an exploded view of a dual-polarized antenna base station provided in the second embodiment of the present invention.

[0034] Figure 10 It is a schematic diagram of the bottom structure of a dual-polarized antenna base station provided in the second embodiment of the present invention. Detailed implementation manners

[0035] Hereinafter, the technical solutions of the present invention will be described in detail with reference to the accompanying drawings and specific embodiments.

[0036] Embodiment 1

[0037] As Figure 1 shown, a phase shifter feeding network based on a multi-cavity coaxial transmission line provided in an embodiment of the present invention includes a phase shifter 3, a multi-cavity metal profile 1, and six signal transmission lines disposed in the multi-cavity metal profile 1. The six signal transmission lines are respectively a first signal transmission line 21, a second signal transmission line 22, a third signal transmission line 23, a fourth signal transmission line 24, a fifth signal transmission line 25, and a sixth signal transmission line 26.

[0038] Combined with Figure 2 shown, the multi-cavity metal profile 1 is an integrally formed part, and the interior of the multi-cavity metal profile 1 is provided with a plurality of cylindrical cavities 10 that are parallel to each other. The plurality of cylindrical cavities 10 penetrate the multi-cavity metal profile along the Y-axis direction and are arranged side by side in sequence along the X-axis direction.

[0039] The phase shifter 3 is fixedly connected to the bottom surface of the multi-cavity metal profile 1. The phase shifter 3 has one input end and five output ends. The input end of the phase shifter 3 is connected to the first signal transmission line 21, and the five output ends of the phase shifter are respectively connected to the second signal transmission line 22, the third signal transmission line 23, the fourth signal transmission line 24, the fifth signal transmission line 25, and the sixth signal transmission line 26. Specifically, a plurality of feeding holes are provided on the side wall of the bottom surface of the multi-cavity metal profile 1. A feeding probe is provided at each input end and output end of the phase shifter 3. The phase shifter 3 is connected to the signal transmission line in the cylindrical cavity 10 by passing the feeding probe through the feeding hole on the side wall of the multi-cavity metal profile 1. The input end of the phase shifter 3 is connected to an external feeding signal source through a signal transmission line, and the output ends of the phase shifter 3 are respectively connected to the antenna unit through a signal transmission line to distribute feeding signals with a phase difference to the antenna unit.

[0040] Each signal transmission line in the present invention respectively includes a plurality of metal tubes 2 connected in sequence, and the plurality of metal tubes 2 are distributed in the same or different cylindrical cavities 10; wherein, each metal tube 2 is respectively supported in the cylindrical cavity 10 by a support connecting member 20 and is coaxially arranged with the cylindrical cavity 10; the support connecting member 20 is made of an insulating medium, so that the metal tube 2 is not in contact with and not electrically connected to the multi-cavity metal profile 1; the multi-cavity metal profile 1 is grounded, so that the metal tube 2 can transmit a feeding signal in the cylindrical cavity 10 in TEM mode.

[0041] In a signal transmission line, the plurality of metal tubes 2 included are sequentially connected by a bridging member 42 or a connecting column 41; wherein, two metal tubes 2 distributed in different cylindrical cavities 10 are connected by a bridging member 42, and two metal tubes 2 distributed in the same cylindrical cavity 10 are connected by a connecting column 41.

[0042] Among them, the multi-cavity metal profile 1 can be made of an aluminum profile or a copper profile, and the metal tube can be made of a metal copper tube, an electroplated aluminum tube or an electroplated die-cast aluminum alloy tube. Preferably, the multi-cavity metal profile 1 in the embodiment of the present invention is an aluminum profile and is made by an integrated pultrusion process; the metal tube 2 in the embodiment of the present invention is a metal copper tube.

[0043] The support connecting member 20 is an integrally formed part and can be made of an insulating material with high temperature resistance characteristics and a low dielectric constant such as PTFE, PPS, etc., so as to minimize the transmission loss of the feeding signal.

[0044] Next, taking the first signal transmission line 21 and the second signal transmission line 22 as examples, the specific structure of the signal transmission line will be described.

[0045] Combined Figure 3 As shown, the first signal transmission line 21 includes three metal tubes 2 arranged in the same cylindrical cavity 10, and the three metal tubes 2 are respectively supported in the cylindrical cavity 10 by a support connecting member 20, and the three metal tubes 2 are sequentially connected by a connecting column 41.

[0046] Among them, the support connecting member 20 is in a circular ring shape, its inner diameter matches the outer diameter of the metal tube 2, and its outer diameter matches the inner diameter of the cylindrical cavity 10; the support connecting member 20 is sleeved outside the metal tube 2 to support the metal tube 2 in the cylindrical cavity 10 of the multi-cavity metal profile 1 and make the axis of the metal tube 2 coincide with the axis of the cylindrical cavity 10.

[0047] The connecting column 41 is arranged between two adjacent sections of metal pipes 2, and the connecting column 41 is made of the same material as the metal pipe 2. When two sections of metal pipes 2 arranged in the same cylindrical cavity 10 are connected by the connecting column 41, the outer diameters of both ends of the connecting column 41 respectively match the inner diameters of the two sections of metal pipes 2 to be connected, and both ends of the connecting column 41 are respectively inserted into the ends of the two sections of metal pipes 2 to connect and conduct the two sections of metal pipes 2 to each other. As an improvement, a radially sunken annular groove is arranged in the middle of the connecting column 41, and a fixing ring 410 is arranged in the annular groove. The fixing ring 410 is directly formed in the annular groove of the connecting column 41 by an integral injection molding process; the outer diameter of the fixing ring 410 matches the inner diameter of the cylindrical cavity 10 and is used to support the connecting column 41 in the cylindrical cavity 10.

[0048] Combined Figure 4 As shown, the second signal transmission line 22 includes four sections of metal pipes 2, and the four sections of metal pipes 2 are respectively supported and arranged in four different cylindrical cavities 10 through support connectors 20. The four sections of metal pipes 2 are sequentially connected through a bridging member 42.

[0049] Specifically, the bridging member 42 includes a bridging plug 421 and a metal conductive sheet 422 fixed in the bridging plug 421. A bridging window hole 11 communicating with the outside is provided on the top surface or the bottom surface side wall of the cylindrical cavity 10. When two sections of metal pipes distributed in two different cylindrical cavities are connected by a bridging member, the bridging plug 421 of the bridging member 42 is plugged into the bridging window holes 11 connecting the two cylindrical cavities 10 from the outside of the multi-cavity metal profile 1, so that the metal conductive sheet 422 is respectively in contact with the two sections of metal pipes 2 at the bridging window holes 11 of the two cylindrical cavities 10 to connect and conduct the two sections of metal pipes 2 to each other.

[0050] As an improvement, since in the second signal transmission line 22, the two sections of metal pipes 2 connected to each other are both distributed in adjacent cylindrical cavities 10, when arranging the bridging window holes 11, the bridging window holes 11 of two adjacent cylindrical cavities 10 can be directly communicated as a whole. Thereby reducing the opening cost of the bridging window holes 11 and improving the convenience and stability when installing the bridging member 42.

[0051] Through the above structure, the signal transmission line in the embodiment of the present invention adopts the multi-cavity metal profile 1 and the metal pipe 2 to realize a transmission structure equivalent to a coaxial line, and the main mode of its signal transmission is the TEM mode, and both the electric field and the magnetic field are in the plane perpendicular to the propagation direction.

[0052] Specifically, each cylindrical cavity 10 inside the multi-cavity metal profile 1 in this embodiment can be equivalent to the outer conductor of a coaxial line, while the metal tube 2 disposed inside the cylindrical cavity 10 is equivalent to the inner conductor of the coaxial line. The metal tube 2 transmits the feeding signal in the cylindrical cavity 10 in the TEM mode. The electric field of the TEM mode points from the outer wall of the inner conductor to the inner wall of the outer conductor, and the magnetic field is distributed around the inner conductor. This mode has no radiation loss during transmission and is hardly affected by external signals. On the other hand, since each cylindrical cavity 10 is completely isolated from each other, the coupling between the cylindrical cavities 10 is zero, which can effectively avoid the mutual influence of the electromagnetic waves generated by each signal transmission line and helps to greatly improve the transmission efficiency.

[0053] On this basis, the present invention connects multiple metal tubes 2 in sequence through the connecting posts 41 and the bridging members 42 to form multiple independent signal transmission lines, providing sufficient freedom for the arrangement of the signal transmission lines. Different lengths of metal tubes 2 can be combined with the connecting posts 41 and the bridging members 42 to flexibly build signal transmission lines with different orientations, which can better meet the requirements of different engineering designs, have sufficient flexibility and applicability, and have broad application prospects.

[0054] At the same time, the feeding network of the phase shifter in this embodiment can achieve unified grounding through the multi-cavity metal profile 1, so that all cylindrical cavities 10 have a common ground. For the current distribution, having a common ground can not only achieve the consistency of the current distribution density but also reduce the current density at local positions, thereby ensuring the consistency of the overall circuit performance and improving the intermodulation index.

[0055] Combined Figure 5 and Figure 6 As shown, the phase shifter in this embodiment includes a main circuit board 31, a coupling sliding piece 32, a fixed pressing piece 33, a rotating shaft 34, and a transmission rack 35. The main circuit board 31, the coupling sliding piece 32, and the fixed pressing piece 33 are sequentially stacked on the bottom surface of the multi-cavity metal profile 1; the main circuit board 31 is fixedly connected to the bottom surface of the multi-cavity metal profile 1 by screws. The rotating shaft 34 sequentially penetrates the multi-cavity metal profile 1, the main circuit board 31, the coupling sliding piece 32, and the fixed pressing piece 33 along the Z-axis direction. The rotating shaft 34 is rotatably connected to the main circuit board 31 and fixedly connected to the coupling sliding piece 32 and the fixed pressing piece 33, so that the coupling sliding piece 32 and the fixed pressing piece 33 can rotate relative to the main circuit board 1.

[0056] Both ends of the transmission rack 35 are slidably and limitedly connected to the bottom surface of the multi-cavity metal profile 1 through the limit connecting pieces 350. The transmission rack 35 is in gear transmission connection with the fixed pressing piece 33 and is used to adjust the rotation angle of the fixed pressing piece 33.

[0057] On one side of the main circuit board 31 facing the coupling sliding plate 32, a transmission microstrip line 311 and two phase delay microstrip lines 312 are printed. One end of the transmission microstrip line 311 is the input end of the phase shifter 3, and the other end of the transmission microstrip line 311 is an output end of the phase shifter 3. The two phase delay microstrip lines 312 are arranged in parallel with each other. A phase adjustment section in an arc shape is provided in the middle of each phase delay microstrip line 312, and each phase adjustment section takes the rotating shaft 34 as the center of the circle. The two ends of each phase delay microstrip line 312 are respectively two output ends of the phase shifter 3. Thus, one end of the transmission microstrip line 311 and the two ends of the two phase delay microstrip lines 312 respectively form an input end and five output ends of the phase shifter 3.

[0058] On one side of the coupling sliding plate 32 facing the main circuit board 31, a coupling microstrip line 320 is printed. The fixed pressing plate 33 is fixedly connected to the coupling sliding plate 32 and presses the coupling sliding plate 32 against the main circuit board 31, so that the coupling microstrip line 320 on the coupling sliding plate 32 is simultaneously coupled with the transmission microstrip line 311 and the two phase delay microstrip lines 312 on the main circuit board 31 to conduct the input end of the phase shifter 3 and each output end.

[0059] When the driving rack 35 drives the fixed pressing plate 33 to rotate, it simultaneously drives the coupling sliding plate 32 to rotate, so that the coupling microstrip line 320 on the coupling sliding plate 32 slides synchronously along the circumferential direction within the phase adjustment section of the two phase delay microstrip lines 312 to adjust the phase difference between the input end of the phase shifter 3 and each output end.

[0060] The phase shifter 3 in this embodiment adopts a highly integrated modular design and uses a feeding probe to realize the connection with the signal transmission line, which can be installed, built, disassembled and replaced conveniently and quickly. At the same time, the phase difference of each output end can be quickly and synchronously adjusted through the driving rack 35, which can meet different phase adjustment requirements.

[0061] Embodiment Two

[0062] As Figures 7 to 10 shown, a dual-polarized base station antenna provided in this embodiment includes the phase shifter feeding network described in Embodiment One, and also includes a first RF connector 61, a second RF connector 62 and five dual-polarized antenna units 5.

[0063] Among them, in order to realize the dual polarization of the antenna unit, two phase shifter feeding networks are required to respectively provide the feeding signals of the two polarizations to the dual-polarized antenna unit 5. The two phase shifter feeding networks are respectively a first phase shifter feeding network 71 and a second phase shifter feeding network 72. The first phase shifter feeding network 71 and the second phase shifter feeding network 72 are symmetrically arranged and share the same multi-cavity metal profile 1.

[0064] The first RF connector 61 and the second RF connector 62 are fixedly connected to the bottom surface of the multi-cavity metal profile 1. The first RF connector 61 is used to connect to an external first coaxial cable to introduce a first polarization feed signal, and the second RF connector 62 is used to connect to an external second coaxial cable to introduce a second polarization feed signal; the five dual-polarization antenna units 5 are arranged in an array and fixedly connected to the middle of the top surface of the multi-cavity metal profile 1.

[0065] In the first phase shifter feeding network 71, the input end of the phase shifter 3 is connected to the first RF connector 61 through a signal transmission line to receive the first polarization feed signal; the five output ends of the phase shifter 3 are respectively connected to the five dual-polarization antenna units 5 through signal transmission lines in one-to-one correspondence to distribute the first polarization feed signal with a phase difference to the five dual-polarization antenna units 5; In the second phase shifter feeding network 72, the input end of the phase shifter 3 is connected to the second RF connector 62 through a signal transmission line to receive the second polarization feed signal; the five output ends of the phase shifter 3 are respectively connected to the five dual-polarization antenna units 5 through signal transmission lines in one-to-one correspondence to distribute the second polarization feed signal with a phase difference to the five dual-polarization antenna units 5.

[0066] Specifically, feeding probes are respectively provided at the tops of the first RF connector 61 and the second RF connector 62. The first RF connector 61 is connected to the first phase shifter feeding network 71 by passing the feeding probe at the top through the side wall of the multi-cavity metal profile 1, and the second RF connector 62 is connected to the second phase shifter feeding network 72 by passing the feeding probe at the top through the side wall of the multi-cavity metal profile 1; A first polarization feeding probe and a second polarization feeding probe are respectively provided at the bottom of each dual-polarization antenna unit 5 for receiving the first polarization feed signal and the second polarization feed signal; the five dual-polarization antenna units 5 are respectively connected to the first phase shifter feeding network through the first polarization feeding probes, and the five dual-polarization antenna units 5 are respectively connected to the second phase shifter feeding network through the second polarization feeding probes.

[0067] Combined Figure 10 As shown, as an improvement, the phase shifters 3 of the first phase shifter feeding network 71 and the second phase shifter feeding network 72 share the same driving rack 35. The driving rack 35 is arranged in the middle of the bottom surface of the multi-cavity metal profile 1. The two phase shifters 3 are symmetrically arranged on both sides of the driving rack 35, and the fixed pressing pieces 33 of the two phase shifters are connected to the driving rack 35 by synchronous tooth transmission. Through the driving rack 35, the phases of the first phase shifter feeding network 71 and the second phase shifter feeding network 72 can be adjusted synchronously with equal amplitude.

[0068] Furthermore, a plurality of mounting seats 12 are fixedly connected to the bottom of the multi-cavity metal profile 1. The multi-cavity metal profile 1 is fixed in the working environment through the mounting seats 12 and connected to the ground. Reflective side plates 13 are fixedly connected to both sides of the top surface of the multi-cavity metal profile 1 respectively. The reflective side plates 13 are inclined, so that the top of the dual-polarized base station antenna forms a horn-shaped structure with an upward opening, which is used to form the reflection boundary of the base station antenna and adjust the pattern beamwidth convergence.

[0069] Embodiment III

[0070] This embodiment provides a single-polarized base station antenna, which includes the phase shifter feeding network described in Embodiment I, and also includes a radio frequency connector and five single-polarized antenna elements. Taking the dual-polarized base station antenna in Embodiment II as a reference, this embodiment is equivalent to removing a phase shifter feeding network and a radio frequency connector on the basis of Embodiment II, and at the same time replacing the dual-polarized antenna element with a single-polarized antenna element.

[0071] Specifically, in this embodiment, the radio frequency connector is fixedly connected to the bottom surface of the multi-cavity metal profile, and is used to connect with an external coaxial cable to introduce a feeding signal; the five single-polarized antenna elements are arranged in an array and fixedly connected to the middle of the top surface of the multi-cavity metal profile; In the phase shifter feeding network, the input end of the phase shifter is connected to the radio frequency connector through a signal transmission line to receive the feeding signal; the five output ends of the phase shifter are respectively connected to the five single-polarized antenna elements through signal transmission lines in one-to-one correspondence to distribute feeding signals with a phase difference to the five single-polarized antenna elements.

[0072] Specifically, feeding probes are respectively provided at the top of the radio frequency connector and the bottom of the single-polarized antenna element. The radio frequency connector and the single-polarized antenna element are respectively connected to the phase shifter feeding network by passing the feeding probes through the side wall of the multi-cavity metal profile.

[0073] The above embodiments only represent several implementation manners of the present invention. The description is relatively specific and detailed, but it should not be construed as a limitation on the scope of the patent of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several deformations and improvements can still be made, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention should be subject to the appended claims.

Claims

1. A phase shifter feeding network based on a multi-cavity coaxial transmission line, characterized in that: It includes a phase shifter, a multi-cavity metal profile, and N+1 signal transmission lines arranged in the multi-cavity metal profile; The multi-cavity metal profile is an integrally formed part, and a plurality of cylindrical cavities parallel to each other are arranged inside the multi-cavity metal profile. The plurality of cylindrical cavities penetrate the multi-cavity metal profile along the Y-axis direction and are arranged side by side in sequence along the X-axis direction; Each signal transmission line comprises a plurality of metal tube segments connected in sequence, and the plurality of metal tube segments are distributed in the same or different cylindrical cavities; wherein each metal tube segment is supported in the cylindrical cavity by a supporting connector and is coaxially arranged with the cylindrical cavity; the supporting connector is made of an insulating medium, so that the metal tube and the multi-cavity metal profile do not contact and conduct with each other; the multi-cavity metal profile is grounded, so that the metal tube can transmit the feeding signal in the cylindrical cavity in a TEM mode; The phase shifter is fixedly connected to the bottom surface of the multi-cavity metal profile, and has an input end and N output ends; the N+1 signal transmission lines are connected to the input end and the N output ends of the phase shifter in a one-to-one correspondence.

2. The phase shifter feeding network based on multi-cavity coaxial transmission line according to claim 1, characterized in that: A feeding probe is provided at each input and output end of the phase shifter. The phase shifter passes through the side wall of the multi-cavity metal profile through the feeding probe to be connected to the signal transmission line in the cylindrical cavity. The input end of the phase shifter is connected to the external feeding signal source through the signal transmission line, and the output end of the phase shifter is connected to the antenna unit through the signal transmission line to distribute the feeding signal with a phase difference to the antenna unit.

3. The phase shifter feeding network based on multi-cavity coaxial transmission line according to claim 2, characterized in that: In a signal transmission line, several sections of metal tubes are connected in sequence through bridges or connecting columns; among them, two sections of metal tubes distributed in different cylindrical cavities are connected through bridges, and two sections of metal tubes distributed in the same cylindrical cavity are connected through connecting columns.

4. The phase shifter feeding network based on multi-cavity coaxial transmission line according to claim 3, characterized in that: The connecting column is made of the same material as the metal tube; when two sections of metal tubes arranged in the same cylindrical cavity are connected through the connecting column, the outer diameters at both ends of the connecting column respectively match the inner diameters of the two sections of metal tubes to be connected, and the two ends of the connecting column are respectively inserted into the ends of the two sections of metal tubes to connect the two sections of metal tubes to each other and conduct them.

5. The phase shifter feeding network based on multi-cavity coaxial transmission line according to claim 3, characterized in that: The bridging member includes a bridging plug and a metal conductive sheet fixed in the bridging plug; a bridging window hole connected to the outside is provided on the top or bottom side wall of the cylindrical cavity; when two sections of metal pipes distributed in two different cylindrical cavities are connected through the bridging member, the bridging plug of the bridging member is sealed and connected to the bridging window holes of the two cylindrical cavities from the outside of the multi-cavity metal profile, so that the metal conductive sheet contacts the two sections of metal pipes at the bridging window holes of the two cylindrical cavities respectively, so as to connect the two sections of metal pipes to each other and conduct electricity.

6. The phase shifter feeding network based on multi-cavity coaxial transmission line according to claim 2, characterized in that: The phase shifter comprises a main circuit board, a coupling slide, a fixed pressing plate, a rotating shaft and a transmission rack; The main circuit board, the coupling slide and the fixed pressing sheet are sequentially stacked on the bottom surface of the multi-cavity metal profile; the main circuit board is fixedly connected to the multi-cavity metal profile, and the rotating shaft sequentially penetrates the multi-cavity metal profile, the main circuit board, the coupling slide and the fixed pressing sheet along the Z-axis direction. The rotating shaft is rotatably connected to the main circuit board and is fixedly connected to the coupling slide and the fixed pressing sheet, so that the coupling slide and the fixed pressing sheet can rotate relative to the main circuit board; The transmission rack is slidably connected to the bottom surface of the multi-cavity metal profile through a limiting connection piece, and the transmission rack is drivingly connected to the fixed pressing plate teeth to adjust the rotation angle of the fixed pressing plate; A transmission microstrip line and a plurality of phase-delay microstrip lines are printed on one side of the main circuit board facing the coupling slide, one end of the transmission microstrip line is the input end of the phase shifter, and the other end of the transmission microstrip line is an output end of the phase shifter; the plurality of phase-delay microstrip lines are arranged in parallel with each other, and a circular arc-shaped phase adjustment section is provided in the middle of each phase-delay microstrip line, and the phase adjustment section takes the rotating shaft as the center of the circle, and the two ends of each phase-delay microstrip line are respectively two output ends of the phase shifter; A coupling microstrip line is printed on one side of the coupling slide facing the main circuit board, and the fixed pressing sheet is fixedly connected to the coupling slide and presses the coupling slide against the main circuit board, so that the coupling microstrip line on the coupling slide is coupled with the transmission microstrip line and the phase delay microstrip line on the main circuit board at the same time, so as to conduct the input end of the phase shifter with each output end; When the transmission rack drives the fixed pressing plate to rotate, it synchronously drives the coupling slide to rotate, so that the coupling microstrip line on the coupling slide synchronously slides along the circumferential direction within the phase adjustment interval of each phase delay microstrip line to adjust the phase difference between the input end and each output end of the phase shifter.

7. The phase shifter feeding network based on multi-cavity coaxial transmission line according to claim 1, characterized in that: The multi-cavity metal profile is an aluminum profile and is made through an integrated pultrusion process.

8. The phase shifter feeding network based on multi-cavity coaxial transmission line according to claim 1, characterized in that: The metal tube is a metal copper tube.

9. A single-polarized base station antenna, comprising the phase shifter feeding network according to any one of claims 1 to 8, characterized in that: Also includes a radio frequency connector and N single-polarized antenna units; The RF connector is fixedly connected to the bottom surface of the multi-cavity metal profile and is used to connect to an external coaxial cable to introduce a feeding signal; the N single-polarized antenna units are arranged in an array and fixedly connected to the middle of the top surface of the multi-cavity metal profile; In the phase shifter feeding network, the input end of the phase shifter is connected to the RF connector via a signal transmission line to receive a feeding signal; The N output ends of the phase shifter are connected to the N single-polarized antenna units one by one through signal transmission lines, so as to distribute feeding signals with phase differences to the N single-polarized antenna units; The top of the RF connector and the bottom of the single-polarized antenna unit are respectively provided with feeding probes, and the RF connector and the single-polarized antenna unit are respectively connected to the phase shifter feeding network by passing through the side walls of the multi-cavity metal profile through the feeding probes.

10. A dual-polarized base station antenna, comprising the phase shifter feeding network according to any one of claims 1 to 8, characterized in that: Also includes a first radio frequency connector, a second radio frequency connector and N dual-polarized antenna units; There are two phase shifter feeding networks, namely a first phase shifter feeding network and a second phase shifter feeding network; The first phase shifter feeding network and the second phase shifter feeding network are symmetrically arranged and share the same multi-cavity metal profile; The first RF connector and the second RF connector are fixedly connected to the bottom surface of the multi-cavity metal profile, the first RF connector is used to connect to an external first coaxial cable to introduce a first polarized feeding signal, and the second RF connector is used to connect to an external second coaxial cable to introduce a second polarized feeding signal; the N dual-polarized antenna units are arranged in an array and fixedly connected to the middle of the top surface of the multi-cavity metal profile; In the first phase shifter feeding network, an input end of the phase shifter is connected to a first RF connector via a signal transmission line to receive a first polarized feeding signal; The N output ends of the phase shifter are connected to the N dual-polarization antenna units one by one through signal transmission lines, so as to distribute the first polarization feeding signal with phase difference to the N dual-polarization antenna units; In the second phase shifter feeding network, the input end of the phase shifter is connected to the second RF connector through a signal transmission line to receive a second polarized feeding signal; The N output ends of the phase shifter are connected to the N dual-polarization antenna units one by one through signal transmission lines, so as to distribute the second polarization feeding signal with phase difference to the N dual-polarization antenna units; A feeding probe is provided on the top of the first RF connector and the second RF connector, respectively. The first RF connector is connected to the first phase shifter feeding network through the feeding probe, and the second RF connector is connected to the second phase shifter feeding network through the feeding probe. A first polarization feeding probe and a second polarization feeding probe are provided at the bottom of each dual-polarization antenna unit; the N dual-polarization antenna units are respectively connected to the first phase shifter feeding network through the first polarization feeding probe, and the N dual-polarization antenna units are respectively connected to the second phase shifter feeding network through the second polarization feeding probe.

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