Multi-transmission line morphing phase shifter and base station antenna device

Abstract

The application discloses a multi-transmission line mode fused phase shifter and a base station antenna device. The multi-transmission line mode fused phase shifter comprises a phase shifter cavity, a plurality of inner cavities separated by an inner cavity wall, and a cavity window arranged on the side of the inner cavity. A plurality of PCB feed lines are inserted into the guide rail on the inner side of the inner cavity along the longitudinal opening direction of the inner cavity to form a suspended strip line. An adapter circuit is arranged on the PCB feed line and is arranged opposite the cavity window to form an air microstrip line. A coaxial cable is arranged outside the phase shifter cavity. The cable core at one end of the coaxial cable is connected with the adapter circuit through the cavity window. The coaxial cable, the PCB feed line and the phase shifter cavity are electrically connected to form a coaxial transmission line. The application uses the air microstrip line as a transition structure to realize the adapter design of the suspended strip line and the coaxial transmission line, which can effectively reduce the energy loss of the signal in the transmission process and improve the transmission efficiency of the overall system.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of communication antennas, in particular to a multi-transmission line form integrated phase shifter and a base station antenna device. BACKGROUND

[0002] At present, the internal key devices of a base station antenna mainly include phase shifters, power dividers, couplers, filters and combiners, and the performance of these antenna devices directly affects the radiation performance of the base station antenna. In these devices, the most commonly used transmission line forms include strip lines, microstrip lines, coaxial transmission lines and waveguide designs, and the main function of the transmission line is to transmit high-frequency energy from the transmitter to the input end of the antenna with minimum loss, or to transmit it to the receiver in the opposite direction. Different types of transmission lines play different roles in the design of base station antennas due to their unique physical characteristics and applicable scenarios.

[0003] However, in actual engineering applications, base station antenna devices designed with different transmission line forms have different problems: although waveguide design has the lowest loss, its high cost and large weight limit its application in civilian fields; strip line has low loss, but its complexity and difficulty in implementation result in low versatility; microstrip line is widely used in civilian base station antennas due to its small size, light weight and low cost, but its biggest disadvantage is relatively large loss and small power capacity; due to impedance matching problems, the use frequency of coaxial transmission line in wideband base stations is gradually decreasing. Therefore, in order to solve the above problems, a base station antenna device combining the advantages of multiple transmission line forms is needed to solve various problems in the current design process of base station antenna devices. SUMMARY

[0004] The present application aims to at least solve one of the technical problems in the prior art, and provides a multi-transmission line form integrated phase shifter and a base station antenna device, which can effectively reduce the energy loss of signals in the transmission process and improve the transmission efficiency of the overall system through the transition structure of the air microstrip line to complete the structure design of the transition part of the suspended strip line and the coaxial transmission line.

[0005] In a first aspect, the embodiments of the present application provide a multi-transmission line form integrated phase shifter, comprising: a phase shifter cavity including a plurality of inner cavities separated by an inner cavity wall, the side of the inner cavity being provided with a cavity window; a plurality of PCB feed lines inserted into the guide rail on the inner side of the inner cavity along the longitudinal opening direction of the inner cavity, the PCB feed line being provided with a transition line, and the transition line being disposed opposite the cavity window; a coaxial cable provided outside the phase shifter cavity, the cable core of one end of the coaxial cable being connected with the transition line through the cavity window, and the coaxial cable, the PCB feed line and the phase shifter cavity being electrically conductive.

[0006] In some embodiments, the multi-transmission line mode fusion phase shifter further comprises a plurality of sliding insertion phase shifting medium structures in the inner cavity, the phase shifting medium structure comprises upper and lower phase shifting medium layers, the upper and lower phase shifting medium layers are respectively arranged on the upper and lower sides of the corresponding PCB feed line, and a corresponding plug is arranged between the upper and lower phase shifting medium layers, the plug slides longitudinally in the hollow track of the PCB feed line to limit the sliding position of the phase shifting medium structure in the phase shifter cavity.

[0007] In some embodiments, the phase shifting medium layer is provided with a first rectangular window and a second rectangular window of different sizes, and the upper surface and the lower surface of the phase shifting medium layer are both provided with a plurality of hemispherical protrusions.

[0008] In some embodiments, the front surface and the back surface of the PCB feed line are both provided with the same metal trace layer, and the metal trace layer is realized by a plurality of metal vias, the part of the metal trace layer without phase shifting medium layer covering is in contact with air to form a suspended strip line structure.

[0009] In some embodiments, the phase shifter cavity is integrally formed by pultrusion of a profiled body of metal aluminum material, the inner cavity of the phase shifter cavity comprises a first inner cavity and a second inner cavity separated by an inner cavity wall, and two U-shaped wiring grooves are respectively arranged on the outer sides of the first inner cavity and the second inner cavity in a mirror image manner, the U-shaped wiring grooves are arranged vertically to the side surface of the profiled body and are integrated with the outer cavity of the profiled body, and the U-shaped wiring grooves are used to fix the coaxial cable.

[0010] In some embodiments, the cavity window comprises a top surface window and a side surface window respectively arranged on the top surface and the side surface of the phase shifter cavity, the top surface window and the side surface window are through, the side surface window is smaller than the top surface window, the U-shaped wiring grooves are respectively arranged on the left and right sides of the side surface window, and a preset gap is left between the U-shaped wiring grooves on the left and right sides.

[0011] In some embodiments, the coaxial cable comprises a metal shielding layer, a cable medium and a cable core, one end of the coaxial cable connected with the adapter circuit is stripped of the metal shielding layer, is bent by 90° at the junction of the metal shielding layer and the cable medium, is stripped of a preset length of the cable core at the top end of the cable medium, and the cable core is welded with the adapter circuit.

[0012] In some embodiments, the coaxial cable passes through the top surface window and the side surface window, the cable core of the coaxial cable is connected with the PCB feed line by forming a tin pile through welding, the metal shielding layer of the coaxial cable is held by the U-shaped wiring groove of the cavity side surface, and the metal shielding layer of the coaxial cable is welded with the U-shaped wiring groove through tin soldering to ensure electrical connection.

[0013] In some embodiments, the multi-transmission line form integrated phase shifter further comprises a fixed pin arranged on the top of the phase shifter cavity, the fixed pin passes through the special-shaped hole on the top surface of the phase shifter cavity, the circular hole on the PCB feed line substrate, and the circular hole on the inner cavity wall and the bottom surface of the phase shifter cavity, and the circular protrusion on the fixed pin is embedded into the circular hole on the top surface of the phase shifter cavity by rotating 90° to fix the PCB feed line.

[0014] In the second aspect, the embodiments of the present application provide a base station antenna device, comprising the multi-transmission line form integrated phase shifter according to any one of the embodiments of the first aspect.

[0015] According to the embodiments of the present application, a multi-transmission line form integrated phase shifter and a base station antenna device are provided, which have at least the following beneficial effects: the multi-transmission line form integrated phase shifter comprises a phase shifter cavity including a plurality of inner cavities separated by an inner cavity wall, the side surface of the inner cavity is provided with a cavity windowing; a plurality of PCB feed lines are inserted into the guide rail located on the inner side of the inner cavity along the longitudinal opening direction of the inner cavity, the PCB feed line is provided with a switching line, and the switching line is arranged opposite to the cavity windowing; a coaxial cable is arranged outside the phase shifter cavity, the cable core at one end of the coaxial cable is connected with the switching line through the cavity windowing, and the coaxial cable, the PCB feed line and the phase shifter cavity are electrically conducted. It can be understood that the plurality of PCB feed lines are inserted into the guide rail located on the inner side of the inner cavity along the longitudinal opening direction of the inner cavity, the part of the metal trace layer not covered by the phase shifting medium contacts the air to form a suspended strip line structure; the switching line of the PCB feed line is arranged opposite to the cavity windowing and uses the metal wall between the upper and lower inner cavities as a reference ground to form an air microstrip line structure with air as the medium; the coaxial cable is arranged outside the phase shifter cavity, the cable core at one end of the coaxial cable is connected with the switching line through the cavity windowing to realize electrical conduction, and corresponds to a coaxial transmission line; wherein the air microstrip line structure as a transition structure can realize the switching between the suspended strip line and the coaxial transmission line, so that the present application can use the suspended strip line as the main body of the phase shifter, use the coaxial transmission line as the port, and use the air microstrip line as the connection transition between the two, effectively reducing the energy loss of the signal in the transmission process, improving the transmission efficiency of the overall system, reducing noise and interference, and improving the signal-to-noise ratio, so as to complement the advantages of multiple transmission line forms, have the characteristics of low loss and high efficiency.

[0016] Other features and advantages of the present application will be set forth in the descriptions below, and in part will become apparent to those skilled in the art upon examination of the following or can be learned by practice of the present application. The objects and other advantages of the present application can be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings. BRIEF DESCRIPTION OF DRAWINGS

[0017] The accompanying drawings are used to provide further understanding of the technical solutions of the present application, and constitute a part of the specification, and are used to explain the technical solutions of the present application together with embodiments of the present application, and do not constitute a limitation on the technical solutions of the present application.

[0018] The present application is further illustrated below in conjunction with the drawings and embodiments.

[0019] Figure 1 is a schematic view of the oblique upper direction of the multi-transmission line form fusion phase shifter provided by the embodiments of the present application;

[0020] Figure 2 is a schematic view of the longitudinal opening direction of the multi-transmission line form fusion phase shifter provided by the embodiments of the present application;

[0021] Figure 3 is a schematic view of the connection between the phase shifter cavity and the coaxial cable provided by the embodiments of the present application;

[0022] Figure 4 is a schematic view of the profile embryo corresponding to the phase shifter cavity provided by the embodiments of the present application;

[0023] Figure 5 is a partial schematic view of the U-shaped wiring groove provided by the embodiments of the present application;

[0024] Figure 6 is a top view and a sectional view of the phase shifter cavity provided by the embodiments of the present application;

[0025] Figure 7 is a schematic view of the PCB feed line provided by the embodiments of the present application;

[0026] Figure 8 is a schematic view of the phase shifter medium structure provided by the embodiments of the present application;

[0027] Figure 9 is a curve graph of the voltage standing wave ratio (VSWR) changing with frequency provided by the embodiments of the present application;

[0028] Figure 10 is a curve graph of the characteristic impedance (Z0) changing with frequency provided by the embodiments of the present application.

[0029] Reference signs:

[0030] 100, multi-transmission line form fusion phase shifter; 1, phase shifter cavity; 2, PCB feed line; 3, coaxial cable; 4, phase shifter medium structure; 5, fixed bolt; 10, profile embryo. DETAILED DESCRIPTION

[0031] The specific embodiments of the present application will be described in detail below, the preferred embodiments of the present application are shown in the accompanying drawings, the role of the drawings is to supplement the description of the text part of the description, so that people can intuitively and visually understand each technical feature and the overall technical solution of the present application, but it cannot be understood as a limitation on the scope of protection of the present application.

[0032] In the description of the present application, the meaning of one or more is one or more, the meaning of multiple is more than two, greater than, less than, more than, etc. are understood as not including the number, above, below, within, etc. are understood as including the number, "any one" means one or more, "at least one of the following" and the like means any combination of these items, including any combination of single or multiple items. If the first, second is described, it is only used for the purpose of distinguishing technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features or the order of indicated technical features.

[0033] It should be noted that the terms such as setting, installing and connecting in the embodiments of the present application should be understood broadly, and those skilled in the art can determine the specific meaning of the above terms in the embodiments of the present application in combination with the specific content of the technical solution. For example, the term "connection" can be mechanical connection, electrical connection or can communicate with each other; it can be directly connected, or indirectly connected through an intermediate medium.

[0034] It should be noted that the technical features involved in each embodiment of the present application described below can be combined with each other as long as there is no conflict between them.

[0035] Currently, the base station antenna mainly contains phase shifters, power dividers, couplers, filters and combiners and other key devices inside, the performance of these antenna devices directly affects the radiation performance of the base station antenna, among these devices, the most commonly used transmission line forms include strip line, microstrip line, coaxial transmission line and waveguide design, the main function of the transmission line is to transmit high-frequency energy from the transmitter to the antenna input end or to the receiver in reverse direction with minimum loss, different types of transmission lines play different roles in the design of base station antenna due to their unique physical characteristics and applicable scenarios. However, in actual engineering application, base station antenna devices designed by different transmission line forms have different problems: although the waveguide design has the lowest loss, its high cost and large weight limit its application in the civil field; although the strip line has low loss, its complexity and difficulty in implementation result in low universality; the microstrip line is widely used in civil base station antenna due to its small size, light weight and low cost, but its biggest disadvantage is relatively large loss and small power capacity; due to the problem of impedance matching, the use frequency of coaxial transmission line in wideband base station is gradually reduced. Therefore, in order to solve the above problems, a base station antenna device combining the advantages of various transmission line forms is needed to solve various problems in the current design process of base station antenna device.

[0036] Based on this, reference Figures 1 to 8 , Figure 1 is a schematic view of the inclined upward direction of the multi-transmission line form fusion phase shifter provided by the embodiment of the application; Figure 2 is a schematic view of the longitudinal opening direction of the multi-transmission line form fusion phase shifter provided by the embodiment of the application; Figure 3 is a schematic view of the connection between the phase shifter cavity and the coaxial cable provided by the embodiment of the application; Figure 4 is a schematic view of the profile embryo corresponding to the phase shifter cavity provided by the embodiment of the application; Figure 5 is a partial schematic view of the U-shaped wiring groove provided by the embodiment of the application; Figure 6 is a top view and sectional view of the phase shifter cavity provided by the embodiment of the application; Figure 7 is a schematic view of the PCB feed line provided by the embodiment of the application; Figure 8 is a schematic view of the phase shift medium structure provided by the embodiment of the application.

[0037] In a first aspect, the embodiments of the present application provide a multi-transmission line mode fusion phase shifter 100, comprising: a phase shifter cavity 1, comprising a plurality of inner cavities separated by an inner cavity wall, the side of the inner cavity is provided with a cavity window; a plurality of PCB feed lines 2, inserted into the guide rail on the inner side of the inner cavity along the longitudinal opening direction of the inner cavity, the PCB feed line 2 is provided with a switching line, and the switching line is deployed opposite to the cavity window; a coaxial cable 3 is arranged outside the phase shifter cavity 1, and the cable core at one end of the coaxial cable 3 is connected with the switching line through the cavity window, and the coaxial cable 3, the PCB feed line 2 and the phase shifter cavity 1 are electrically conductive.

[0038] The phase shifter cavity 1 is the shell of the entire device, made of metal material, used to accommodate and protect the internal components, and the phase shifter cavity 1 is internally divided into a plurality of independent inner cavities, which are separated by an inner cavity wall to reduce electromagnetic interference between different signal paths, and the side of the inner cavity is provided with a cavity window for connecting the coaxial cable 3.

[0039] In some embodiments, the inner cavity wall is a metal wall, and the phase shifter cavity 1 is internally divided into a plurality of independent inner cavities, such as a first inner cavity and a second inner cavity, by the metal wall, which provides physical isolation to ensure minimal mutual interference between different signal paths, and the side of the inner cavity is provided with a cavity window for mounting and connecting the coaxial cable 3.

[0040] The PCB feed line 2 is a transmission line on a printed circuit board, used to transmit signals from one point to another, and the PCB feed line 2 is inserted into the guide rail on the inner side of the inner cavity along the longitudinal opening direction of the inner cavity to ensure its stability in the cavity, and the PCB feed line 2 is provided with switching lines, which are deployed opposite to the cavity window for electrical connection with the coaxial cable 3.

[0041] The coaxial cable 3 is a signal transmission cable with a four-layer structure of center conductor, insulating layer, shielding layer and outer sheath, and one end of the coaxial cable 3 is stripped of the metal shielding layer to expose the internal cable core for welding with the switching line on the PCB feed line 2, and the metal shielding layer of the coaxial cable 3 is used to prevent external electromagnetic interference and is fixed on the phase shifter cavity 1 through a U-shaped wiring groove.

[0042] It can be understood that the plurality of PCB feed lines 2 are inserted into the guide rail on the inner side of the inner cavity along the longitudinal opening direction of the inner cavity, and the part of the metal trace layer not covered by the phase-shifting medium contacts the air to form a suspended stripline structure; the transfer line of the PCB feed line 2 is arranged opposite to the cavity window, and the metal wall between the upper and lower inner cavities is used as a reference ground to form an air microstrip line structure with air as the medium; the coaxial cable 3 is arranged outside the phase shifter cavity 1, and the cable core at one end thereof is connected with the transfer line through the cavity window to realize electrical conduction and correspond to the coaxial transmission line; the air microstrip line structure as a transition structure can realize the transition between the suspended stripline and the coaxial transmission line, so that the present application can use the suspended stripline as the phase shifter main body, use the coaxial transmission line as the port, and use the air microstrip line as the connection transition between the two, effectively reduce the energy loss of the signal in the transmission process, improve the transmission efficiency of the overall system, reduce noise and interference, and improve the signal-to-noise ratio, so as to complement the advantages of various transmission line forms, have the characteristics of low loss and high efficiency.

[0043] It can be understood that the suspended stripline is used as the phase shifter main body, the suspended stripline is a form of microwave transmission line in which the signal line is placed "suspended" in the air or other low dielectric constant medium instead of directly contacting the metal cavity, the front and back surfaces of the substrate of the PCB feed line 2 are provided with the same metal trace layer, and are connected through multiple metal vias, the part of the metal trace layer not covered by the phase-shifting medium contacts the air to form a suspended stripline structure, and air as the medium has a low dielectric constant, which significantly reduces the energy loss in signal transmission, and the suspended stripline avoids direct contact of the signal line with the metal surface, reduces reflection and interference, and improves the purity and efficiency of signal transmission.

[0044] It can be understood that one end of the coaxial cable 3 is stripped to expose the internal cable core, and is connected with the transfer line on the PCB feed line 2 through welding, the transfer line on the PCB feed line 2 is arranged opposite to the cavity window, and the metal wall between the upper and lower inner cavities is used as a reference ground to form a microstrip line structure with air as the medium, and the air microstrip line as a transition structure between the suspended stripline and the coaxial transmission line ensures smooth conversion of the signal from one transmission line form to another transmission line form, reduces transmission loss, and through the transfer line and the cavity window in the present application, unnecessary reflection and interference are reduced, and the efficiency of signal transmission is further improved.

[0045] In some embodiments, the multi-transmission line mode fusion phase shifter 100 further comprises a plurality of sliding insertion phase shifting medium structures 4 in the inner cavity, the phase shifting medium structure 4 comprises upper and lower phase shifting medium layers, and the upper and lower phase shifting medium layers are respectively arranged on the upper and lower sides of the corresponding PCB feed line 2. A corresponding plug is arranged between the two phase shifting medium layers, and the corresponding plug slides longitudinally in the hollow track of the PCB feed line 2 to limit the sliding position of the phase shifting medium structure 4 in the phase shifter cavity 1.

[0046] The phase shifting medium structure 4 is a medium for adjusting the phase of the signal, made of low-loss material, and the phase shifting medium structure 4 comprises upper and lower phase shifting medium layers, respectively arranged on the upper and lower sides of the corresponding PCB feed line 2.

[0047] In some embodiments, as shown in Figure 8 The upper surface and the lower surface of the phase shifting medium layer are provided with a plurality of hemispherical protrusions, the first rectangular window and the second rectangular window of different sizes are used to optimize the signal transmission characteristics in different frequency bands, and the upper surface and the lower surface of the phase shifting medium layer are provided with a plurality of hemispherical protrusions to reduce the friction generated when the phase shifting medium slides in the cavity.

[0048] It can be understood that the phase shifting medium structure 4 can be injection molded by using low-loss PPE material, the dielectric constant is 4.4, the tangent angle loss is 0.0008, two first rectangular windows 4b1 and second rectangular windows 4b2 of different sizes are arranged on the phase shifting medium structure 4, which can ensure good matching in a wide frequency band, and a plurality of hemispherical protrusions 4a are arranged on the upper surface and the lower surface of the phase shifting medium, which can reduce the friction generated when the phase shifting medium structure 4 slides in the cavity. In addition, a corresponding plug 4c is arranged between the upper and lower phase shifting media, which can slide longitudinally in the hollow track 2d of the PCB feed line 2, and can prevent the phase shifter medium from falling off during sliding in the cavity.

[0049] In some embodiments, the front surface and the back surface of the PCB feed line 2 are provided with the same metal trace layer, and the metal trace layer is realized by a plurality of metal vias; the part of the metal trace layer not covered by the phase shifting medium layer is in contact with air to form a suspended strip line structure; it can be understood that the PCB feed line 2 is inserted into the guide rail 1g in the inner cavity along the longitudinal opening direction of the cavity, and then the PCB feed line 2 and the inner cavity form a suspended strip line, and the metal trace layer not covered by the phase shifting medium structure 4 has air as the transmission medium, so that the other parts of the cavity except the area covered by the phase shifting medium structure 4 can have lower transmission loss.

[0050] In some embodiments, as shown in Figure 4As shown, the phase shifter cavity 1 is integrally pultruded from a profiled body 10 of aluminum material, the inner cavity of the phase shifter cavity 1 includes a first inner cavity and a second inner cavity separated by an inner cavity wall, and corresponding U-shaped wiring slots are arranged on the mirror image sides of the first inner cavity and the second inner cavity, the U-shaped wiring slots are arranged perpendicular to the side of the profiled body 10 and are integrated with the outer cavity of the profiled body 10, and the U-shaped wiring slots are used to fix the coaxial cable 3; wherein the phase shifter cavity 1 of the multi-transmission line form integrated phase shifter 100 is a profiled body integrally pultruded from aluminum material, which is open in the longitudinal direction to facilitate the realization of the pultrusion process, and is closed in other directions, and when the feed line is arranged inside the cavity, the closed outer cavity can function as a reference ground, for example, Figure 4 The profiled body 10 of the aluminum material inside the cavity is arranged with two inner cavities 10a and 10b, and two U-shaped wiring slots 10c and 10d are arranged on the sides of the outer cavity, the U-shaped wiring slots are arranged perpendicular to the side of the profiled body 10, one side of the U-shaped wiring slot is integrated with the outer cavity of the profiled body 10, and the contact area between the U-shaped wiring slot and the cavity itself is reduced as much as possible to reduce the heat dissipation of the metal cavity during welding and improve the welding quality. The two U-shaped wiring slots 10c and 10d are respectively arranged in mirror image on the two inner cavities 10a and 10b, as shown in Figure 6 As shown, guide rails 1g protruding 1mm from the inner cavity wall are arranged on the left and right sides of the inner cavities 10a and 10b.

[0051] In some embodiments, as shown in Figure 7 The PCB feed line 2 uses low-loss PTFE material as the substrate 2a, the substrate thickness is 0.762mm, the dielectric constant is 2.2, the tangent angle loss is 0.0009, the same metal trace layer 2b1 and metal trace layer 2b2 are provided on the front and back surfaces of the substrate 2a, the metal trace layer 2b1 and the metal trace layer 2b2 are connected by multiple metal vias 2c, multiple metal vias 2c are arranged between the two metal trace layers, which strengthens the overall hardness of the PCB feed line 2, and at the same time, the upper and lower metal trace layers are connected to form a whole, which is equivalent to increasing the thickness of the feed line and reducing the heat loss. The surface of the metal trace layer is subjected to a silver plating process, and the silver plating thickness is 0.005mm, the silver plating process improves the conductivity of the metal trace layer, and the cost is moderate, which further reduces the transmission loss.

[0052] In some embodiments, the cavity window includes a top window and a side window provided on the top surface and the side surface of the phase shifter cavity 1 respectively, the top window and the side window are through, the side window is smaller than the top window, and the U-shaped wiring slots are arranged on the left and right sides of the side window.

[0053] Specifically, as shown in Figure 5As shown, two windows of different sizes are arranged on the top surface and side surface of the cavity, the top surface window is located on the top surface of the cavity, the side surface window is located on the side surface of the cavity, the top surface window and the side surface window are through, and the side surface window is smaller than the top surface window. The side surface window has two structural features, a main window 1b1 and a chamfer 1b2. Two U-shaped wiring grooves 1c with a length of 10 mm are arranged on the left and right sides of the side surface window respectively, and a gap 1d is left between the two U-shaped wiring grooves.

[0054] In some embodiments, the coaxial cable 3 includes a metal shielding layer, a cable medium and a cable core. The end of the coaxial cable 3 connected with the adapter line is stripped of the metal shielding layer, bent 90° along the junction of the metal shielding layer and the cable medium, and the cable core with a preset length is stripped at the top end of the cable medium. The cable core is welded with the adapter line. Specifically, as shown in Figure 3 As shown, the coaxial transmission line adopts the form of a low-loss coaxial cable 3 with an impedance of 50Ω, a low-density polytetrafluoroethylene medium, a relative dielectric constant of 1.56 and a propagation rate of 80%. One end of the coaxial cable 3 is stripped of the metal shielding layer, bent 90° along the junction of the metal shielding layer and the cable medium, and the cable core with a length of 3 mm is stripped at the top end of the cable medium.

[0055] In some embodiments, the coaxial cable 3 passes through the top surface window and the side surface window. The cable core of the coaxial cable 3 is connected with the PCB feed line 2 by forming a tin pile through welding. The metal shielding layer of the coaxial cable 3 is supported by the U-shaped wiring groove on the side surface of the cavity, and the metal shielding layer of the coaxial cable 3 is welded with the U-shaped wiring groove by adding tin, so as to ensure electrical conduction.

[0056] In some embodiments, as shown in Figure 3 and Figure 7 As shown, the coaxial cable 3 passes through the window 1a on the top surface of the cavity and the window 1b on the side surface of the cavity. The cable core of the coaxial cable 3 is placed on the adapter line 2e of the PCB feed line 2 and connected with the PCB feed line 2 by forming a tin pile 3a through welding. The metal shielding layer 3c of the coaxial cable 33 can be supported by the U-shaped wiring groove 1c on the side surface of the cavity. The metal shielding layer 3c of the coaxial cable 33 and the U-shaped wiring groove 1c can be welded together by adding tin to the U-shaped wiring groove 1c, thereby realizing electrical conduction between the coaxial cable 3 and the phase shifter. The coaxial cable 3 can be arranged in the left and right directions.

[0057] The gap 1d between the two U-shaped wiring grooves 1c can reduce the heat dissipation speed of the metal cavity during welding and improve the welding quality. At the same time, the window on the side surface of the metal cavity is chamfered 1b2, which can hold the medium 3b of the coaxial cable 33, so that the coaxial cable 3 is not easy to fall off from the multi-transmission line integrated phase shifter 100. At the same time, it can also avoid introducing other auxiliary structural members to realize the fixation of the coaxial cable 3, thereby reducing the intermodulation failure point.

[0058] In some embodiments, the multi-transmission line mode fusion phase shifter 100 further comprises a fixed pin arranged at the top of the phase shifter cavity 1, the fixed pin passes through the special-shaped hole on the top surface of the phase shifter cavity 1, the round hole on the substrate of the PCB feed line 2, and the round hole on the inner cavity wall and the bottom surface of the phase shifter cavity 1, and by rotating 90°, the round protrusion on the fixed pin is embedded into the round hole on the top surface of the phase shifter cavity 1 to fix the PCB feed line 2, so that the PCB feed line 2 does not shake in the cavity, thereby improving the stability of the PCB feed line 2.

[0059] In some embodiments, as shown in Figure 6 , the top surface of the cavity is provided with a round hole 1f and a combined hole 1e, the round hole 1f is arranged only on the top surface of the phase shifter cavity 1, and the combined hole 1e penetrates the whole cavity. It can be understood that the round hole 1f is a special-shaped hole on the top surface of the phase shifter cavity 1, which is large in the middle and small at both ends. The interface between the two inner cavities and the bottom surface of the phase shifter cavity 1 are provided with round holes.

[0060] In summary, in the present application, part of the metal trace layer of the PCB feed line 2 is not covered by the phase shifting medium, directly contacts the air, and forms a suspended strip line structure. The air as a low dielectric constant medium significantly reduces the energy loss in signal transmission. The different size rectangular windows on the phase shifting medium layer optimize the signal transmission characteristics under different frequency bands, further reducing the transmission loss. Using air as the main transmission medium reduces the energy loss of the signal in the transmission process, improves the transmission efficiency of the overall system, and the low loss characteristic helps to maintain the integrity of the signal, reduces noise and interference, and improves the signal-to-noise ratio. Furthermore, the present application deploys the adapter line directly opposite the cavity window, realizes electrical conduction through welding, reduces unnecessary reflection and interference, and forms an air microstrip line transition structure. Through the air microstrip line transition structure, smooth conversion between the suspended strip line and the coaxial transmission line can be realized, ensuring efficient transmission of signals from one transmission line form to another, and realizing the conversion of the three transmission line forms.

[0061] In addition, the conversion between the three transmission line forms in the present application does not introduce additional structural parts for fixation, has few electrical failure points, and is stable in intermodulation.

[0062] In some embodiments, the present application can use a 50-ohm standard impedance coaxial cable 3 to be suitable for various application scenarios and allow the coaxial cable 3 to be deployed in left and right directions, so that the present application can use the suspended strip line as the phase shifter main body, use the 50-ohm low-loss coaxial transmission line as the port, and use the air microstrip line as the connection transition between the two, avoiding the shortcomings of various transmission lines in traditional solutions, integrating the three different transmission line forms together, realizing the design of antenna devices, and having universality and expansibility.

[0063] Referring to Figures 9 to 10 ,Figure 9 is a curve graph of voltage standing wave ratio (VSWR) changing with frequency provided by an embodiment of the present application; Figure 10 is a curve graph of characteristic impedance (Z0) changing with frequency provided by an embodiment of the present application; Figure 9 In the figure, the horizontal axis (X axis) represents the frequency range, the unit is GHz (gigahertz), and the frequency range is from 1.69 GHz to 2.69 GHz; the vertical axis (Y axis) represents the VSWR value, which is less than 1.1; Figure 10 In the figure, the horizontal axis (X axis) represents the frequency range, the unit is GHz (gigahertz), and the vertical axis (Y axis) represents the characteristic impedance value, the unit is ohm (Ω), and is stable at 50 ohms; it can be seen that the application completes the transition structure design of the suspended strip line and the coaxial transmission line by using the air microstrip line, that is, using the suspended strip line as the main body of the phase shifter, using the 50-ohm low-loss coaxial transmission line as the port, and using the air microstrip line as the connection transition between the two, through the corresponding specific size settings in the above embodiments, the communication effect of meeting the standing wave less than 1.1 and the output port impedance value stable at 50 ohms in the working frequency range of 1690-2690 MHz is realized, and the application has universality.

[0064] In a second aspect, an embodiment of the present application provides a base station antenna device, comprising the multi-transmission line form integrated phase shifter of any one of the first aspect.

[0065] The above has made a detailed description of the embodiments of the present application in combination with the drawings, but the present application is not limited to the above embodiments, and various changes can be made within the knowledge range of ordinary skilled in the art without departing from the purpose of the present application.

Claims

1. A multi-transmission-line fusion phase shifter, characterized in that, include: The phase shifter cavity includes multiple inner cavities separated by an inner cavity wall, and cavity windows are provided on the sides of the inner cavities; Multiple PCB feed lines are inserted into guide rails located inside the inner cavity along the longitudinal opening direction of the inner cavity. The PCB feed lines are equipped with adapter lines, which are deployed facing the opening of the cavity and with the metal wall between the upper and lower inner cavities as the reference ground to form an air microstrip line structure with air as the medium. A coaxial cable is disposed outside the phase shifter cavity. The cable core at one end of the coaxial cable is connected to the adapter line through the cavity opening. The coaxial cable, the PCB feed line, and the phase shifter cavity are electrically connected. in: The multi-transmission-line fusion phase shifter also includes multiple phase-shifting dielectric structures that are slidably inserted into the inner cavity. Each phase-shifting dielectric structure includes upper and lower phase-shifting dielectric layers, which are respectively disposed on the upper and lower sides of the corresponding PCB feed line. The PCB feed line has the same metal trace layer on both the front and back sides of the substrate, and conduction is achieved through multiple metal vias. The part of the metal trace layer not covered by the phase-shifting dielectric layer is exposed to air to form a suspended strip structure.

2. The multi-transmission-line fusion phase shifter according to claim 1, characterized in that, A mating pin is provided between the two phase-shifting dielectric layers. The mating pin slides longitudinally in the hollow track of the PCB feed line to limit the sliding position of the phase-shifting dielectric structure in the phase shifter cavity.

3. The multi-transmission-line fusion phase shifter according to claim 2, characterized in that, The phase-shifting dielectric layer is provided with a first rectangular window and a second rectangular window of different sizes, and the upper and lower surfaces of the phase-shifting dielectric layer are provided with multiple hemispherical protrusions.

4. The multi-transmission-line fusion phase shifter according to claim 1, characterized in that, The phase shifter cavity is integrally pultruded from a profile blank of aluminum metal. The inner cavity of the phase shifter cavity includes a first inner cavity and a second inner cavity separated by an inner cavity wall. Two U-shaped wiring grooves are respectively deployed in mirror image to the outer sides of the first inner cavity and the second inner cavity. The U-shaped wiring grooves are deployed perpendicular to the side of the profile blank and are integrated with the outer cavity of the profile blank. The U-shaped wiring grooves are used to fix the coaxial cable.

5. The multi-transmission-line morphology fusion phase shifter according to claim 4, characterized in that, The cavity opening includes a top window and a side window respectively provided on the top surface and side surface of the phase shifter cavity. The top window and the side window are connected. The side window is smaller than the top window. The left and right sides of the side window are respectively provided with U-shaped wiring grooves, and a preset gap is left between the left and right sides of the U-shaped wiring grooves.

6. The multi-transmission-line fusion phase shifter according to claim 5, characterized in that, The coaxial cable includes a metal shielding layer, a cable medium, and the cable core. At one end of the coaxial cable connected to the adapter line, the metal shielding layer is stripped, and the cable core is bent at 90° at the junction of the metal shielding layer and the cable medium. A predetermined length of the cable core is stripped from the top of the cable medium, and the cable core is welded to the adapter line.

7. The multi-transmission-line fusion phase shifter according to claim 6, characterized in that, The coaxial cable passes through the top and side windows. The cable cores of the coaxial cable are soldered to form a solder pile and are connected to the PCB feed line. The metal shielding layer of the coaxial cable is supported by the U-shaped wiring groove on the side of the cavity, and the metal shielding layer of the coaxial cable is soldered to the U-shaped wiring groove by adding solder to ensure electrical continuity.

8. The multi-transmission-line fusion phase shifter according to claim 1, characterized in that, The multi-transmission line fusion phase shifter also includes a fixing pin disposed on the top of the phase shifter cavity. The fixing pin passes through the irregular hole on the top surface of the phase shifter cavity, the circular hole on the PCB feeder substrate, and the circular holes on the inner cavity wall and the bottom surface of the phase shifter cavity. By rotating 90°, the circular protrusion on the fixing pin is embedded into the circular hole on the top surface of the phase shifter cavity to fix the PCB feeder.

9. A base station antenna device, characterized in that, Including the multi-transmission-line fusion phase shifter as described in any one of claims 1 to 8.

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