Power divider feed network based on multi-cavity coaxial transmission line and base station antenna thereof

Abstract

The invention provides a power divider 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 power divider feed network based on the multi-cavity coaxial transmission line comprises a multi-cavity metal profile and a power divider arranged in the multi-cavity metal profile; a plurality of cylindrical cavities which are parallel to one another are formed in the multi-cavity metal profile; a plurality of sections of metal pipes are distributed in a plurality of cylindrical cavities of the multi-cavity metal profile; wherein each section of metal pipe is supported in the cylindrical cavity through a supporting connecting piece, and the metal pipe and the cylindrical cavity are coaxially arranged; and the plurality of sections of metal tubes are connected with each other through the bridging pieces and the connecting columns to form the power divider with one input end and N output ends. 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 in particular to a power divider feeding network based on a multi-cavity coaxial transmission line and a base station antenna thereof. Background Art

[0002] The feed network is an important component of the base station antenna. It is connected between the antenna port and the radiating element array, forming a path for RF signal transmission and realizing impedance matching, amplitude and phase distribution and other functions. The feed 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 radiating element, or to transmit the high-frequency current from the radiating element to the transmitter.

[0003] In the existing feeding network, the main transmission modes of the feeding signal 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 arranged in the aluminum profile cavity, and the PCB board is printed with circuit structures such as power dividers and phase shifters formed by the stripline network; the stripline transmission is achieved by grounding the aluminum profile cavity so that its upper and lower side walls are equivalent to two parallel grounding plates. The feeding network based on microstrip line transmission is mainly composed of a PCB board, one side of the PCB board is printed with circuit structures such as power dividers and phase shifters formed by the microstrip line network, and the other side of the PCB board is printed with a metal floor.

[0004] However, the feeding networks using these two transmission modes have some defects to a greater or lesser extent.

[0005] First, both feed networks have the problem of too much customization and insufficient flexibility. Specifically, both stripline and microstrip lines need to be printed on PCB boards, which makes the distribution and design indicators of the feed network relatively fixed and difficult to reuse; when the application scenario and design requirements of the feed network change, it is necessary to redesign and print different PCB boards.

[0006] Second, both feed networks have the problem of high production costs. On the one hand, the PCB board cost for printing strip lines and microstrip lines is high, resulting in high overall production costs for related structures. On the other hand, when wiring the stripline-based feed network, the aluminum profile cavity needs to be welded and electroplated, which increases labor costs and process costs, and the high degree of manual participation is not conducive to automated production.

[0007] Third, both feeding networks have different degrees of transmission loss. On the one hand, in the feeding network based on stripline transmission, the main mode of stripline transmission is TEM (transverse electromagnetic wave) mode, and its electric field and magnetic field directions are perpendicular to the propagation direction of the wave. Since all striplines are encapsulated in the same closed aluminum profile cavity through PCB boards, the electromagnetic waves generated by each stripline during signal transmission repeatedly oscillate between the upper and lower ground planes and affect each other, resulting in inevitable interference between the branches, which will introduce transmission loss and reduce transmission efficiency. On the other hand, in the feeding network based on microstrip line transmission, the main mode of microstrip line transmission is quasi-TEM mode, and its electric field and magnetic field are mainly transverse, but there is a small longitudinal component, which causes the microstrip line to form surface waves at the edge of the microstrip line during signal transmission, resulting in radiation loss caused by the external radiation of part of the energy. In addition, since the main mode of the coaxial cable used to introduce the external feeding signal is the TEM mode, there is a conversion of different transmission modes at the connection between the coaxial cable and the microstrip line, which will cause discontinuity in transmission and thus produce discontinuity loss. The more times the different transmission modes are converted, the greater the loss generated.

[0008] It can be seen that the feeding network in the prior art has the defects of poor flexibility, high cost and large loss, and needs to be improved and perfected. Summary of the invention

[0009] The purpose of the present invention is to provide a power divider feeding network based on a multi-cavity coaxial transmission line and a base station antenna thereof, in order to address the problems existing in the prior art, improve the flexibility and applicability of the feeding network, and reduce the production cost and transmission loss of the antenna feeding network.

[0010] To achieve the above object, the present invention adopts the following technical solutions: A power divider feeding network based on a multi-cavity coaxial transmission line, comprising a multi-cavity metal profile and a power divider 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; Several sections of metal tubes are distributed in the multiple cylindrical cavities of the multi-cavity metal profile; wherein each section of the metal tube 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 a feeding signal in the cylindrical cavity in a TEM mode; The several sections of metal tubes are connected to each other through bridges and connecting columns to form a power divider with one input end and N output ends; wherein 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.

[0011] Further, the power splitter includes at least one one-to-two power splitter unit; The one-to-two power splitter unit comprises five sections of metal tubes connected to each other, and the five sections of metal tubes are respectively an input signal transmission tube, an impedance matching tube, a power distribution tube, a first output signal transmission tube, and a second output signal transmission tube; wherein the input signal transmission tube is used as the input end of the one-to-two power splitter unit, the impedance matching tube is used for input impedance matching, the power distribution tube is used for power distribution and output impedance matching, and the first output signal transmission tube and the second output signal transmission tube are respectively used as two output ends of the one-to-two power splitter unit; The impedance matching tube and the power distribution tube are respectively arranged in two different cylindrical cavities, the input signal transmission tube is arranged in the cylindrical cavity where the impedance matching tube is located, and the first output signal transmission tube and the second output signal transmission tube are arranged in the cylindrical cavity where the power distribution tube is located; One end of the input signal transmission tube is connected to one end of the impedance matching tube through a connecting column, the other end of the impedance matching tube is connected to the midpoint of the power distribution tube through a bridge, and the two ends of the power distribution tube are respectively connected to the first output signal transmission tube and the second output signal transmission tube through a connecting column.

[0012] Furthermore, the power divider includes at least three one-to-two power divider units, and the at least three one-to-two power divider units are cascaded to each other to form a power divider with one input end and N output ends.

[0013] Furthermore, 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.

[0014] Furthermore, 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 tubes 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 is respectively in contact with the two sections of metal tubes at the bridging window holes of the two cylindrical cavities to connect the two sections of metal tubes to each other and conduct electricity.

[0015] Further, in the one-to-two power splitter unit, the outer diameters of the input signal transmission tube, the first output signal transmission tube and the second output signal transmission tube are the same, and are different from the outer diameters of the impedance matching tube and the power distribution tube; By using impedance matching tubes with different outer diameters, the characteristic impedance of the impedance matching tube is adjusted to achieve input impedance matching; by using power distribution tubes with different outer diameters, the characteristic impedance of the power distribution tube is adjusted to achieve output impedance matching; by using impedance matching tubes and power distribution tubes with different lengths, the operating frequency of the one-to-two power divider unit is adjusted.

[0016] Furthermore, the multi-cavity metal profile is an aluminum profile, which is made by an integrated pultrusion process, and the metal tube is a metal copper tube; the inner diameter of the cylindrical cavity is 8 mm, and the outer diameter of the metal tube is 1.5~4.5 mm.

[0017] Furthermore, in the one-to-two power splitter unit, the outer diameters of the input signal transmission tube, the first output signal transmission tube and the second output signal transmission tube are 3.5 mm, the outer diameter of the impedance matching tube is 3.0 mm, and the outer diameter of the power distribution tube is 4.0 mm.

[0018] A single-polarized base station antenna, comprising the power divider feeding network described above, and also comprising 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; a feeding probe is provided on the RF connector, and the RF connector passes through the side wall of the multi-cavity metal profile through the feeding probe to connect to the input end of the power divider; 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; a feeding probe is provided at the bottom of each single-polarized antenna unit, and the N single-polarized antenna units are respectively connected to the N output ends of the power divider through the side walls of the multi-cavity metal profile through the feeding probe.

[0019] A dual-polarized base station antenna, comprising the power divider feeding network described above, and further comprising a first radio frequency connector, a second radio frequency connector and N dual-polarized antenna units; There are two power divider feeding networks, namely a first power divider feeding network and a second power divider feeding network; the first power divider feeding network includes a first multi-cavity metal profile and a first power divider arranged in the first multi-cavity metal profile, and the second power divider feeding network includes a second multi-cavity metal profile and a second power divider arranged in the second multi-cavity metal profile; the first multi-cavity metal profile and the second multi-cavity metal profile are arranged side by side and connected in one piece, and the first power divider and the second power divider have the same structure and are symmetrical to each other; The first RF connector is fixedly connected to the bottom surface of the first multi-cavity metal profile and is used to connect to an external first coaxial cable to introduce a first polarized feeding signal; a feeding probe is provided on the first RF connector, and the first RF connector passes through the side wall of the first multi-cavity metal profile through the feeding probe to connect to the input end of the first power divider; The second RF connector is fixedly connected to the bottom surface of the second multi-cavity metal profile and is used to connect to an external second coaxial cable to introduce a second polarized feeding signal; a feeding probe is provided on the second RF connector, and the second RF connector passes through the side wall of the second multi-cavity metal profile through the feeding probe to connect to the input end of the second power divider; The N dual-polarized antenna units are arranged in an array and fixedly connected to the top surface connection of the first multi-cavity metal profile and the second multi-cavity metal profile; the bottom of each dual-polarized antenna unit is provided with a first polarized feeding probe and a second polarized feeding probe, the N dual-polarized antenna units are respectively connected to the N output ends of the first power divider through the side wall of the first multi-cavity metal profile through the first polarized feeding probe, and the N dual-polarized antenna units are respectively connected to the N output ends of the second power divider through the side wall of the second multi-cavity metal profile through the second polarized feeding probe.

[0020] The present invention provides a power divider feeding network based on a multi-cavity coaxial transmission line, which uses a cylindrical cavity of a multi-cavity metal profile as an outer conductor and a metal tube as an inner conductor, thereby realizing a transmission mode with a TEM mode as the main mode. On the one hand, since each cylindrical cavity is completely isolated from each other and the coupling between each cylindrical cavity is zero, it is possible to effectively avoid the electromagnetic waves generated by each signal transmission line from influencing each other, thereby reducing the transmission loss and radiation loss of the feeding signal during the transmission process. On the other hand, since the main mode of the power divider feeding network is consistent with the main mode of the coaxial cable used to introduce the external feeding signal, both are TEM modes, which can avoid discontinuity losses at the connection point. Therefore, the present invention has almost no loss during signal transmission, and greatly improves the signal transmission efficiency of the feeding network.

[0021] On this basis, the power divider feeding network of the present invention uses connecting columns and bridge pieces to connect multiple sections of metal pipes into power dividers with different numbers of ports and different line distribution directions, which provides sufficient freedom for the structural design and line arrangement of the power divider, and can flexibly meet different engineering design requirements in terms of structural distribution and working characteristics. It has sufficient flexibility and applicability and has broad application prospects.

[0022] Based on the above characteristics, the power divider feeding network of the present invention does not require the use of a PCB board, nor does it require welding and electroplating of aluminum profiles during wiring; it not only reduces production costs, but also improves the intermodulation stability of the circuit, is more suitable for automated production, and improves production efficiency.

[0023] The antenna base station of the present invention adopts a modular combined design. The RF connector and the antenna unit are quickly connected to the input and output ends of the power divider through a feeding probe. It can be installed, constructed, disassembled and replaced conveniently and quickly, and can flexibly adapt to the design requirements of different base station antenna systems. It has a wide range of applicability.

[0024] In summary, the power divider feeding network based on multi-cavity coaxial transmission lines and the base station antenna thereof 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 It is a schematic diagram of the overall structure of a power divider feeding network based on a multi-cavity coaxial transmission line provided in Example 1 of the present invention.

[0026] Figure 2 It is an exploded diagram of a power divider feeding network based on a multi-cavity coaxial transmission line provided in the first embodiment of the present invention.

[0027] Figure 3 It is an exploded diagram of the power divider in the first embodiment of the present invention.

[0028] Figure 4 It is a schematic structural diagram of the supporting connecting member in the first embodiment of the present invention.

[0029] Figure 5 It is an exploded diagram of a power divider feeding network based on a multi-cavity coaxial transmission line provided in the second embodiment of the present invention.

[0030] Figure 6 It is a schematic diagram of the structure of a one-to-four power divider in Embodiment 2 of the present invention.

[0031] Figure 7 It is a schematic diagram of the top structure of a dual-polarized antenna base station provided in Embodiment 3 of the present invention.

[0032] Figure 8 It is a schematic diagram of the bottom structure of a dual-polarized antenna base station provided in Embodiment 3 of the present invention.

[0033] Fig. 9 It is an exploded diagram of a dual-polarized antenna base station provided in Embodiment 3 of the present invention.

[0034] Fig.10It is a schematic diagram of the top structure of a dual-polarized antenna base station provided in Embodiment 5 of the present invention.

[0035] Fig.11 It is a schematic diagram of the bottom structure of a dual-polarized antenna base station provided in Embodiment 5 of the present invention.

[0036] Fig.12 It is an exploded diagram of a dual-polarized antenna base station provided in Embodiment 5 of the present invention. DETAILED DESCRIPTION

[0037] The technical solution of the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0038] Embodiment 1

[0039] like Figures 1 to 3 As shown, an embodiment of the present invention provides a power divider feeding network based on a multi-cavity coaxial transmission line, comprising a multi-cavity metal profile 1 and a power divider 2 arranged in the multi-cavity metal profile 1.

[0040] The multi-cavity metal profile 1 is an integrally formed part, and a plurality of cylindrical cavities 10 parallel to each other are arranged inside the multi-cavity metal profile 1. The plurality of cylindrical cavities 10 penetrate the multi-cavity metal profile 1 along the Y-axis direction and are arranged side by side in sequence along the X-axis direction.

[0041] Several sections of metal tubes are distributed in the multiple cylindrical cavities 10 of the multi-cavity metal profile 1; wherein each section of the metal tube is supported in the cylindrical cavity 10 by a supporting connector 3 and is coaxially arranged with the cylindrical cavity 10; the supporting connector 3 is made of an insulating medium, so that the metal tube and the multi-cavity metal profile 1 do not contact and conduct with each other; the multi-cavity metal profile 1 is grounded, so that the metal tube can transmit the feeding signal in the cylindrical cavity 10 in the TEM mode.

[0042] The several sections of metal tubes are interconnected through a bridge 42 and a connecting column 41 to form a power divider 2 with one input end and N output ends; wherein, two sections of metal tubes distributed in different cylindrical cavities 10 are connected through a bridge 42, and two sections of metal tubes distributed in the same cylindrical cavity 10 are connected through a connecting column 41.

[0043] The multi-cavity metal profile 1 can be made of aluminum profile or copper profile, and the metal tube can be made of metal copper tube, electroplated aluminum tube or electroplated die-cast aluminum alloy tube. Preferably, the multi-cavity metal profile 1 in the embodiment of the present invention is an aluminum profile, which is made by an integrated pultrusion process; the metal tube 2 in the embodiment of the present invention is a metal copper tube.

[0044] The supporting connector 3 is an integrally formed part and can be made of insulating materials such as PTFE and PPS that have high temperature resistance and low dielectric constant, so as to minimize the transmission loss of the feeding signal.

[0045] Through the above structure, the embodiment of the present invention adopts a multi-cavity metal profile 1 and a metal tube to realize a transmission structure equivalent to a coaxial line, and the main mode of signal transmission is the TEM mode, and the electric field and the magnetic field are both in a plane perpendicular to the propagation direction. Specifically, each cylindrical cavity 10 inside the multi-cavity metal profile 1 can be equivalent to the outer conductor of a coaxial line, and the metal tube arranged in the cylindrical cavity 10 is equivalent to the inner conductor of the coaxial line. This enables the metal tube to transmit the feeding signal in the cylindrical cavity 10 in the TEM mode, and its electric field 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 the transmission process and is almost not affected by external signals.

[0046] At the same time, since the internal space of each cylindrical cavity 10 is independent and completely isolated from each other, the coupling between the cylindrical cavities 10 is zero, which can effectively avoid the mutual influence of electromagnetic waves generated during signal transmission, help reduce transmission loss, and greatly improve transmission efficiency.

[0047] In addition, all cylindrical cavities 10 are uniformly grounded through the multi-cavity metal profile 1, so that each cylindrical cavity 10 is isolated from each other in the internal space while having a common ground. For current distribution, having a common ground can not only reduce the current density at a local position, but also achieve consistency in current distribution density, thereby ensuring consistency in overall circuit performance and improving intermodulation indicators.

[0048] On this basis, the embodiment of the present invention further uses connecting rods 41 and bridges 42 to connect multiple sections of metal pipes to form a splitter 2 to achieve transmission and power distribution of feed signals in the antenna feed network. Figure 3 As shown, the power divider 2 in the embodiment of the present invention is composed of a one-to-two power divider unit, having an input end and two output ends. Specifically, the one-to-two power divider unit includes five sections of metal tubes connected to each other, and the five sections of metal tubes are input signal transmission tube 21, impedance matching tube 22, power distribution tube 23, first output signal transmission tube 24 and second output signal transmission tube 25 according to different functions. Among them, the input signal transmission tube 21 is used as the input end of the one-to-two power divider unit, the impedance matching tube 22 is used for input impedance matching, the power distribution tube 23 is used for power distribution and output impedance matching, and the first output signal transmission tube 24 and the second output signal transmission tube 25 are respectively used as the two output ends of the one-to-two power divider unit.

[0049] The impedance matching tube 22 and the power distribution tube 23 are respectively arranged in two different cylindrical cavities 10, the input signal transmission tube 21 is arranged in the cylindrical cavity 10 where the impedance matching tube 22 is located, and the first output signal transmission tube 24 and the second output signal transmission tube 25 are arranged in the cylindrical cavity 10 where the power distribution tube 23 is located.

[0050] One end of the input signal transmission tube 21 is connected to one end of the impedance matching tube 22 through a connecting column 41, and the other end of the impedance matching tube 22 is connected to the midpoint of the power distribution tube 23 through a bridge 42. The two ends of the power distribution tube 23 are respectively connected to the first output signal transmission tube 24 and the second output signal transmission tube 25 through a connecting column 41.

[0051] Furthermore, the connecting column 41 is made of the same material as the metal tube; when two sections of metal tubes arranged in the same cylindrical cavity 10 are connected through the connecting column 41, the outer diameters at both ends of the connecting column 41 respectively match the inner diameters of the two sections of metal tubes to be connected, and the two ends of the connecting column 41 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.

[0052] Furthermore, 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 connected to the outside is provided on the top or bottom side wall of the cylindrical cavity 10; when two sections of metal pipes distributed in two different cylindrical cavities 10 are connected through the bridging member 42, the bridging plug 421 of the bridging member 42 is sealed in the bridging window holes 11 of 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 at the bridging window holes 11 of the two cylindrical cavities 10, so as to connect the two sections of metal pipes to each other and conduct electricity.

[0053] As an improvement, since the impedance matching tube 22 and the power distribution tube 23 in this embodiment are distributed in two adjacent cylindrical cavities 10, when the bridge window 11 is provided, the bridge window 11 of the two adjacent cylindrical cavities 10 can be directly connected as one, thereby reducing the hole opening cost of the bridge window 11 and improving the convenience and stability when installing the bridge member 42.

[0054] Combination Figure 4As shown, the support connector 3 includes two arc-shaped support arms 31 located on both sides and a fixing pin 32 located in the middle; one ends of the two arc-shaped support arms 31 are connected to each other, and the middle parts are bent outward respectively, so that a circular arc buckle is formed between the two arc-shaped support arms 31, and the other ends of the two arc-shaped support arms 31 are arranged oppositely to form an opening of the circular arc buckle; one end of the fixing pin 32 is connected to the connection of one end of the two arc-shaped support arms 31, and the other end of the fixing pin 32 extends radially to the opening of the circular arc buckle. The metal tube is provided with a fixing hole that penetrates in the radial direction, and the fixing hole matches the fixing pin 32. When installing the metal tube, the fixing pin 32 of the support connector 3 is passed through the fixing hole on the metal tube in the radial direction, and then placed into the cylindrical cavity 10 together in the axial direction. The inner diameter of the arc-shaped buckle matches the outer diameter of the metal tube, and the overall outer contour diameter of the supporting connector 3 matches the inner diameter of the cylindrical cavity 10, so as to support the metal tube in the cylindrical cavity 10 and make the axis of the metal tube coincide with the axis of the cylindrical cavity 10.

[0055] Figure 4 The structural advantage of the support connector 3 shown is that it is easy to install. The support connector 3 can be fixed on the metal pipe by a simple press-and-snap installation method. It should be noted that in other embodiments, the support connector 3 can also adopt other feasible simplified structures. For example, a circular ring-shaped support connector 3 (not shown) can also be used, and the metal pipe is passed through several support connectors 3 in the axial direction, so that the circular ring-shaped support connector 3 is sleeved on the outside of the metal pipe, the inner diameter of the support connector 3 matches the outer diameter of the metal pipe, and the outer diameter of the support connector 3 matches the inner diameter of the cylindrical cavity 10, so as to support the metal pipe in the cylindrical cavity 10.

[0056] In the process of signal distribution by the power divider 2, impedance matching is required to ensure efficient signal transmission, reduce power loss and signal reflection. When the inner diameter of the cylindrical cavity 10 remains unchanged, the characteristic impedance of each metal tube can be adjusted by using metal tubes with different outer diameters, thereby achieving different impedance matching requirements.

[0057] In this embodiment, the outer diameters of the input signal transmission tube 21, the first output signal transmission tube 24 and the second output signal transmission tube 25 are the same, and are different from the outer diameters of the impedance matching tube 22 and the power distribution tube 23; by using impedance matching tubes 22 with different outer diameter specifications, the characteristic impedance of the impedance matching tube 22 is adjusted, thereby achieving input impedance matching; by using power distribution tubes 23 with different outer diameter specifications, the characteristic impedance of the power distribution tube 23 is adjusted, thereby achieving output impedance matching.

[0058] Specifically, the inner diameter of the cylindrical cavity 10 is 8 mm, and the outer diameter of the metal tube is 1.5-4.5 mm. Among them, the outer diameters of the input signal transmission tube 21, the first output signal transmission tube 24, and the second output signal transmission tube 25 are 3.5 mm, corresponding to the most commonly used 50 ohm transmission line in the communication field; the outer diameter of the impedance matching tube 22 is set to 3.0 mm to achieve input impedance matching; the outer diameter of the power distribution tube 23 is set to 4.0 mm to achieve output impedance matching.

[0059] Furthermore, the operating frequency of the power divider 2 can be adjusted by using impedance matching tubes 22 and power distribution tubes 23 of different lengths. Specifically, the length of the impedance matching tube 22 is about one-fourth of the operating frequency of the power divider 2, and the length of the power distribution tube 23 is about twice that of the impedance matching tube 22.

[0060] It should be noted that the input signal transmission tube 21, the impedance matching tube 22, the power distribution tube 23, the first output signal transmission tube 24 and the second output signal transmission tube 25 in this embodiment actually divide the one-to-two power divider unit into five signal transmission intervals according to their respective functions, and each signal transmission interval is formed by an independent and complete metal tube. It is foreseeable that in other embodiments of the present invention, each signal transmission interval can also be formed by connecting multiple sections of metal tubes with the same diameter in sequence. For example, the power distribution tube 23 can be composed of multiple sections of metal tubes with an outer diameter of 4.0 mm connected in sequence. At this time, the total length of the power distribution tube 23 actually refers to the sum of the lengths of these sections of metal tubes with an outer diameter of 4.0 mm; the same is true for the other signal transmission intervals. These simple splits and changes in the number of metal tubes do not substantially change the structure of the present invention and should be included in the protection scope of the present invention.

[0061] Based on the above structure, the present invention can use multiple sections of metal tubes in conjunction with connecting columns 41 and bridge members 42 to form a power divider 2 with different numbers of ports and different line distribution directions, which provides sufficient freedom for the structural design and line arrangement of the power divider 2, and can flexibly meet different engineering design requirements from the perspective of structural distribution. Furthermore, the present invention can also adjust the impedance matching characteristics and operating frequency of the power divider 2 by changing the outer diameter and length of each metal tube, and can flexibly meet different engineering design requirements from the perspective of operating characteristics. It can be seen that the power divider feeding network of the present invention has sufficient flexibility and applicability, and has broad application prospects.

[0062] Embodiment 2

[0063] Based on the first embodiment, the present invention can also cascade multiple one-to-two power splitter units to form a power splitter with more output ends to meet more complex engineering applications. The second embodiment will be used as an example for detailed description.

[0064] like Figure 5 As shown, the present embodiment provides a power divider feeding network based on a multi-cavity coaxial transmission line, comprising a multi-cavity metal profile 1 and a one-to-four power divider 20 disposed in the multi-cavity metal profile 1. The one-to-four power divider 20 has an input end and four output ends, and is composed of three one-to-two power divider units cascaded to each other.

[0065] Specifically, Figure 6 As shown, the three one-to-two power splitter units are respectively a first one-to-two power splitter unit 2001, a second one-to-two power splitter unit 2002 and a third one-to-two power splitter unit 2003; the input end of the first one-to-two power splitter unit 2001 is the input end of the one-to-four power splitter 20, the two output ends of the first one-to-two power splitter unit 2001 are respectively connected to the input ends of the second one-to-two power splitter unit 2002 and the third one-to-two power splitter unit 2003, and the output ends of the second one-to-two power splitter unit 2002 and the third one-to-two power splitter unit 2003 respectively form four output ends of the one-to-four power splitter 20.

[0066] As an improvement, the connection between the first one-to-two power divider unit 2001 and the second one-to-two power divider unit 2002 can share the same section of metal tube (i.e., the same section of metal tube is used as both the first output signal transmission tube 24 of the first one-to-two power divider unit 2001 and the input signal transmission tube 21 of the second one-to-two power divider unit 2002); the connection between the first one-to-two power divider unit 2001 and the third one-to-two power divider unit 2003 can also share the same section of metal tube (i.e., the same section of metal tube is used as both the second output signal transmission tube 25 of the first one-to-two power divider unit 2001 and the input signal transmission tube 21 of the second one-to-two power divider unit 2002). In this way, the number of connection nodes and metal tubes is reduced, and the effect of simplifying the structure and saving costs is achieved.

[0067] The other structural features of this embodiment are basically the same as those of the first embodiment and will not be described in detail here.

[0068] It is foreseeable that in other embodiments of the present invention, a cascade method similar to that of the present embodiment can also be adopted to connect and combine more one-to-two power splitter units into a power splitter with more output terminals. For example, one more level can be added on the basis of the present embodiment, and one more one-to-two power splitter unit is respectively connected to each output terminal of the second one-to-two power splitter unit 2002 and the third one-to-two power splitter unit 2003, and finally a one-to-eight power splitter and its corresponding power splitter feeding network are formed. These derivative structures that can be obtained through simple association and reasonable deduction should be included in the protection scope of the present invention.

[0069] Embodiment 3

[0070] like Figures 7 to 9 As shown, a dual-polarization base station antenna provided in this embodiment is a dual-unit base station antenna, including the power divider feeding network described in the first embodiment, and also including a first RF connector 61, a second RF connector 62 and two dual-polarization antenna units 5.

[0071] In order to realize the dual polarization of the antenna unit, it is necessary to provide two polarized feeding signals to the dual polarization antenna unit 5 through two power divider feeding networks. The two power divider feeding networks are respectively a first power divider feeding network and a second power divider feeding network; the first power divider feeding network includes a first multi-cavity metal profile 101 and a first power divider 201 arranged in the first multi-cavity metal profile 101, and the second power divider feeding network includes a second multi-cavity metal profile 102 and a second power divider 202 arranged in the second multi-cavity metal profile 102; the first multi-cavity metal profile 101 and the second multi-cavity metal profile 102 are arranged side by side and connected by welding as an integral part, and the first power divider 201 and the second power divider 202 have the same structure and are symmetrical to each other; The first RF connector 61 is fixedly connected to the bottom surface of the first multi-cavity metal profile 101, and is used to connect to an external first coaxial cable to introduce a first polarized feeding signal; a feeding probe is provided on the top of the first RF connector 61, and the first RF connector 61 passes through the side wall of the first multi-cavity metal profile 101 through the feeding probe to connect to the input end of the first power divider 201; The second RF connector 62 is fixedly connected to the bottom surface of the second multi-cavity metal profile 102, and is used to connect to an external second coaxial cable to introduce a second polarized feeding signal; a feeding probe is provided on the top of the second RF connector 62, and the second RF connector 62 passes through the side wall of the second multi-cavity metal profile 102 through the feeding probe to connect to the input end of the second power divider 202; The two dual-polarized antenna units 5 are arranged in an array and fixedly connected to the top surface connection of the first multi-cavity metal profile 101 and the second multi-cavity metal profile 102; the bottom of each dual-polarized antenna unit 5 is provided with a first polarized feeding probe and a second polarized feeding probe, and the two dual-polarized antenna units 5 are respectively connected to the two output ends of the first power divider 201 through the side wall of the first multi-cavity metal profile 101 through the first polarized feeding probe, and the two dual-polarized antenna units 5 are respectively connected to the two output ends of the second power divider 202 through the side wall of the second multi-cavity metal profile 102 through the second polarized feeding probe.

[0072] Furthermore, the bottoms of the first multi-cavity metal profile 101 and the second multi-cavity metal profile 102 are respectively fixedly connected with a plurality of mounting seats 12, and the first multi-cavity metal profile 101 and the second multi-cavity metal profile 102 are fixed in the working environment and connected to the ground through the mounting seats 12. The outer sides of the top surfaces of the first multi-cavity metal profile 101 and the second multi-cavity metal profile 102 are respectively fixedly connected with reflective side plates 13, and the reflective side plates 13 are tilted so that the top of the dual-polarization base station antenna forms a trumpet-shaped structure with an opening upward, which is used to form a reflection boundary of the base station antenna and adjust the wave width convergence of the directional pattern.

[0073] Embodiment 4

[0074] This embodiment provides a single-polarized base station antenna, including the power splitter feeding network described in Embodiment 1, and also including a radio frequency connector and two single-polarized antenna units. Taking the dual-polarized base station antenna in Embodiment 3 as a reference, this embodiment is equivalent to removing a power splitter feeding network and a radio frequency connector on the basis of Embodiment 3, and replacing the dual-polarized antenna unit with a single-polarized antenna unit.

[0075] Specifically, in this embodiment, the RF connector is fixedly connected to the bottom surface of the multi-cavity metal profile and is used to introduce a feeding signal with an external coaxial cable; a feeding probe is provided on the top of the RF connector, and the RF connector passes through the side wall of the multi-cavity metal profile through the feeding probe to connect to the input end of the power divider; The two 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; a feeding probe is provided at the bottom of each single-polarized antenna unit, and the two single-polarized antenna units are respectively connected to the two output ends of the power divider through the side wall of the multi-cavity metal profile through the feeding probe.

[0076] Embodiment 5

[0077] like Figures 10 to 12As shown, the dual-polarization base station antenna provided in this embodiment is a four-unit base station antenna, including the power divider feeding network described in the second embodiment, and also including a first RF connector 61, a second RF connector 62 and four dual-polarization antenna units 5.

[0078] In order to realize the dual polarization of the antenna unit, it is necessary to provide two polarized feeding signals to the dual polarization antenna unit 5 through two power divider feeding networks. The two power divider feeding networks are respectively a first power divider feeding network and a second power divider feeding network; the first power divider feeding network includes a first multi-cavity metal profile 101 and a first one-to-four power divider 201 arranged in the first multi-cavity metal profile 101, and the second power divider feeding network includes a second multi-cavity metal profile 102 and a second one-to-four power divider 202 arranged in the second multi-cavity metal profile 102; the first multi-cavity metal profile 101 and the second multi-cavity metal profile 102 are arranged side by side and connected by welding as an integral part, and the structures of the first one-to-four power divider 201 and the second one-to-four power divider 202 are the same and symmetrical to each other; The first RF connector 61 is fixedly connected to the bottom surface of the first multi-cavity metal profile 101, and is used to connect to an external first coaxial cable to introduce a first polarized feeding signal; a feeding probe is provided on the top of the first RF connector 61, and the first RF connector 61 passes through the side wall of the first multi-cavity metal profile 101 through the feeding probe to connect to the input end of the first one-to-four power divider 201; The second RF connector 62 is fixedly connected to the bottom surface of the second multi-cavity metal profile 102, and is used to connect to an external second coaxial cable to introduce a second polarized feeding signal; a feeding probe is provided on the top of the second RF connector 62, and the second RF connector 62 passes through the side wall of the second multi-cavity metal profile 102 through the feeding probe to connect to the input end of the second one-to-four power divider 202; The four dual-polarized antenna units 5 are arranged in an array and fixedly connected to the top surface connection of the first multi-cavity metal profile 101 and the second multi-cavity metal profile 102; the bottom of each dual-polarized antenna unit 5 is provided with a first polarized feeding probe and a second polarized feeding probe, and the four dual-polarized antenna units 5 are respectively connected to the four output ends of the first one-to-four power divider 201 through the side wall of the first multi-cavity metal profile 101 through the first polarized feeding probe, and the four dual-polarized antenna units 5 are respectively connected to the four output ends of the second one-to-four power divider 202 through the side wall of the second multi-cavity metal profile 102 through the second polarized feeding probe.

[0079] Furthermore, the bottoms of the first multi-cavity metal profile 101 and the second multi-cavity metal profile 102 are respectively fixedly connected with a plurality of mounting seats 12, and the first multi-cavity metal profile 101 and the second multi-cavity metal profile 102 are fixed in the working environment and connected to the ground through the mounting seats 12. The outer sides of the top surfaces of the first multi-cavity metal profile 101 and the second multi-cavity metal profile 102 are respectively fixedly connected with reflective side plates 13, and the reflective side plates 13 are tilted so that the top of the dual-polarization base station antenna forms a trumpet-shaped structure with an opening upward, which is used to form a reflection boundary of the base station antenna and adjust the wave width convergence of the directional pattern.

[0080] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the patent of the present invention. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A power divider feeding network based on a multi-cavity coaxial transmission line, characterized in that: It includes a multi-cavity metal profile and a power divider 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; Several sections of metal tubes are distributed in the multiple cylindrical cavities of the multi-cavity metal profile; wherein each section of the metal tube 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 a feeding signal in the cylindrical cavity in a TEM mode; The several sections of metal tubes are connected to each other through bridges and connecting columns to form a power divider with one input end and N output ends; wherein 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.

2. The power divider feeding network according to claim 1, characterized in that: The power splitter comprises at least one one-to-two power splitter unit; The one-to-two power splitter unit comprises five sections of metal tubes connected to each other, and the five sections of metal tubes are respectively an input signal transmission tube, an impedance matching tube, a power distribution tube, a first output signal transmission tube, and a second output signal transmission tube; wherein the input signal transmission tube is used as the input end of the one-to-two power splitter unit, the impedance matching tube is used for input impedance matching, the power distribution tube is used for power distribution and output impedance matching, and the first output signal transmission tube and the second output signal transmission tube are respectively used as two output ends of the one-to-two power splitter unit; The impedance matching tube and the power distribution tube are respectively arranged in two different cylindrical cavities, the input signal transmission tube is arranged in the cylindrical cavity where the impedance matching tube is located, and the first output signal transmission tube and the second output signal transmission tube are arranged in the cylindrical cavity where the power distribution tube is located; One end of the input signal transmission tube is connected to one end of the impedance matching tube through a connecting column, the other end of the impedance matching tube is connected to the midpoint of the power distribution tube through a bridge, and the two ends of the power distribution tube are respectively connected to the first output signal transmission tube and the second output signal transmission tube through a connecting column.

3. The power divider feeding network according to claim 2, characterized in that: The power divider comprises at least three one-to-two power divider units, and the at least three one-to-two power divider units are cascaded to each other to form a power divider with one input end and N output ends.

4. The power divider feeding network according to claim 2, 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 power divider feeding network according to claim 2, 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 power divider feeding network according to claim 2, characterized in that: In the one-to-two power splitter unit, the outer diameters of the input signal transmission tube, the first output signal transmission tube and the second output signal transmission tube are the same, and are different from the outer diameters of the impedance matching tube and the power distribution tube; By using impedance matching tubes with different outer diameters, the characteristic impedance of the impedance matching tube is adjusted to achieve input impedance matching; by using power distribution tubes with different outer diameters, the characteristic impedance of the power distribution tube is adjusted to achieve output impedance matching; by using impedance matching tubes and power distribution tubes with different lengths, the operating frequency of the one-to-two power divider unit is adjusted.

7. The power divider feeding network according to claim 6, characterized in that: The multi-cavity metal profile is an aluminum profile, which is made by an integrated pultrusion process, and the metal tube is a metal copper tube; the inner diameter of the cylindrical cavity is 8 mm, and the outer diameter of the metal tube is 1.5-4.5 mm.

8. The power divider feeding network according to claim 6, characterized in that: In the one-to-two power splitter unit, the outer diameters of the input signal transmission tube, the first output signal transmission tube and the second output signal transmission tube are 3.5 mm, the outer diameter of the impedance matching tube is 3.0 mm, and the outer diameter of the power distribution tube is 4.0 mm.

9. A single-polarized base station antenna, comprising the power divider 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; a feeding probe is provided on the RF connector, and the RF connector passes through the side wall of the multi-cavity metal profile through the feeding probe to connect to the input end of the power divider; 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; a feeding probe is provided at the bottom of each single-polarized antenna unit, and the N single-polarized antenna units are respectively connected to the N output ends of the power divider through the side walls of the multi-cavity metal profile through the feeding probe.

10. A dual-polarized base station antenna, comprising the power divider 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 power divider feeding networks, namely a first power divider feeding network and a second power divider feeding network; the first power divider feeding network includes a first multi-cavity metal profile and a first power divider arranged in the first multi-cavity metal profile, and the second power divider feeding network includes a second multi-cavity metal profile and a second power divider arranged in the second multi-cavity metal profile; the first multi-cavity metal profile and the second multi-cavity metal profile are arranged side by side and connected in one piece, and the first power divider and the second power divider have the same structure and are symmetrical to each other; The first RF connector is fixedly connected to the bottom surface of the first multi-cavity metal profile and is used to connect to an external first coaxial cable to introduce a first polarized feeding signal; a feeding probe is provided on the first RF connector, and the first RF connector passes through the side wall of the first multi-cavity metal profile through the feeding probe to connect to the input end of the first power divider; The second RF connector is fixedly connected to the bottom surface of the second multi-cavity metal profile and is used to connect to an external second coaxial cable to introduce a second polarized feeding signal; A feeding probe is provided on the second RF connector, and the second RF connector passes through the side wall of the second multi-cavity metal profile through the feeding probe to be connected to the input end of the second power divider; The N dual-polarized antenna units are arranged in an array and fixedly connected to the top surface connection of the first multi-cavity metal profile and the second multi-cavity metal profile; the bottom of each dual-polarized antenna unit is provided with a first polarized feeding probe and a second polarized feeding probe, the N dual-polarized antenna units are respectively connected to the N output ends of the first power divider through the side wall of the first multi-cavity metal profile through the first polarized feeding probe, and the N dual-polarized antenna units are respectively connected to the N output ends of the second power divider through the side wall of the second multi-cavity metal profile through the second polarized feeding probe.

Images