Multi-transmission line form fusion type phase shifter and base station antenna device

Abstract

The invention discloses a multi-transmission line form fusion type phase shifter and a base station antenna device, and the phase shifter comprises a phase shifter cavity which comprises a plurality of inner cavities separated by inner cavity walls, and the side surface of each inner cavity is provided with a cavity window; the plurality of PCB feeder lines are inserted into a guide rail located on the inner side of the inner cavity in the longitudinal opening direction of the inner cavity to form a suspended strip line, switching lines are arranged on the PCB feeder lines, and the switching lines are arranged right opposite to the cavity window to form an air microstrip line; the coaxial cable is arranged on the outer side of the phase shifter cavity, a cable core at one end of the coaxial cable is connected with the switching circuit through the cavity window, and the coaxial cable, the PCB feeder line and the phase shifter cavity are electrically conducted to form a coaxial transmission line; according to the invention, the air microstrip line is used as a transition structure, so that the switching design of the suspended strip line and the coaxial transmission line is realized, the energy loss of the signal in the transmission process can be effectively reduced, and the transmission efficiency of the whole system is improved.

Description

Technical Field

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

[0002] Currently, the interior of a base station antenna mainly includes key devices such as a phase shifter, a power divider, a coupler, a filter, and a combiner. 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 stripline, microstrip line, coaxial transmission line, and waveguide design, etc. The main function of the transmission line is to transfer high - frequency energy from the transmitter to the antenna input terminal with minimum loss, or vice versa to the receiver. 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 the civilian field; Although the stripline has relatively low loss, its complex structure and high implementation difficulty result in low versatility; The microstrip line is widely used in civilian base station antennas because of its small size, light weight, and low cost, but its biggest drawback is relatively large loss and small power capacity; Due to impedance - matching problems, the use frequency of coaxial transmission lines in wide - band base stations is gradually decreasing. Therefore, to solve the above problems, it is necessary to design a base station antenna device that combines the advantages of multiple transmission - line forms to solve various problems faced in the design process of current base station antenna devices. Summary of the Invention

[0004] An object of the present invention is to solve at least one of the technical problems existing in the prior art, and to provide a multi - transmission - line - form fusion phase shifter and a base station antenna device. By completing the design of the transition part structure between the suspended stripline and the coaxial transmission line through an air - microstrip - line transition structure, the energy loss of the signal during transmission can be effectively reduced, and the transmission efficiency of the overall system can be improved.

[0005] In a first aspect, an embodiment of the present invention provides a multi - transmission - line - form fusion phase shifter, including: a phase - shifter cavity, including a plurality of inner cavities separated by inner cavity walls, and a cavity window is provided on the side surface of the inner cavity; a plurality of PCB feeders are inserted into a guide rail located inside the inner cavity along the longitudinal opening direction of the inner cavity, a transition circuit is provided on the PCB feeder, and the transition circuit is deployed opposite to the cavity window; a coaxial cable is provided outside the phase - shifter cavity, and the cable core at one end of the coaxial cable is connected to the transition circuit through the cavity window, and electrical conduction is achieved between the coaxial cable, the PCB feeder, and the phase - shifter cavity.

[0006] In some embodiments, the multi-transmission line fusion phase shifter also includes multiple phase-shifting medium structures slidably inserted into the inner cavity, the phase-shifting medium structure includes two upper and lower phase-shifting medium layers, the two phase-shifting medium layers are respectively arranged on the upper and lower sides of the corresponding PCB feeder, and a matching pin is arranged between the two phase-shifting medium layers, and the matching pin slides longitudinally in the hollow track of the PCB feeder to limit the sliding position of the phase-shifting medium structure in the phase shifter cavity.

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

[0008] In some embodiments, the front and back sides of the substrate of the PCB feed line are provided with the same metal routing layer, and conduction is achieved through multiple metal vias. The part of the metal routing layer not covered by the phase-shifting medium is in contact with the air to form a suspended stripline structure.

[0009] In some embodiments, the phase shifter cavity is formed by integral pultrusion of metal aluminum material, and the inner cavity of the phase shifter cavity includes a first inner cavity and a second inner cavity separated by an inner cavity wall from top to bottom, and corresponding U-shaped wiring grooves are deployed in mirror images on the outer sides of the first inner cavity and the second inner cavity. The U-shaped wiring grooves are deployed perpendicular to the sides of the embryo and are connected to the outer cavity as a whole, and the U-shaped wiring is used to fix the coaxial cable.

[0010] In some embodiments, the cavity window includes a top window and a side window respectively provided on the top surface and the 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, and the U-shaped wiring grooves are respectively provided on the left and right sides of the side window, and a preset gap is left between the U-shaped wiring grooves on the left and right sides.

[0011] In some embodiments, the metal shielding layer is peeled off at one end of the coaxial cable connected to the transfer line, and the cable is bent 90° along the junction between the metal shielding layer and the cable medium. The cable core of a preset length is peeled off at the top of the cable medium, and the cable core is welded to the transfer line.

[0012] In some embodiments, the coaxial cable passes through the top window and the side window, the cable core of the coaxial cable is connected to the PCB feed line by welding to form a tin pile, the metal shielding layer of the coaxial cable is supported by a U-shaped wiring groove on the side of the cavity, and the metal shielding layer of the coaxial cable is welded to the U-shaped wiring groove by adding tin to ensure electrical conduction.

[0013] In some embodiments, the multi-transmission line fusion phase shifter also includes a fixing pin arranged on the top of the phase shifter cavity, the fixing pin passes through the special-shaped 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, and the circular protrusion on the fixing pin is embedded in the circular hole on the top surface of the phase shifter cavity by rotating 90° to fix the PCB feeder.

[0014] In a second aspect, an embodiment of the present invention provides a base station antenna device, comprising a multi-transmission line fusion phase shifter as described in any one of the embodiments in the first aspect.

[0015] According to an embodiment of the present invention, a multi-transmission line fusion type phase shifter and a base station antenna device are provided, which have at least the following beneficial effects: the multi-transmission line fusion type phase shifter comprises: a phase shifter cavity, comprising a plurality of inner cavities separated by inner cavity walls, and a cavity window is arranged on the side of the inner cavity; a plurality of PCB feeders are inserted into a guide rail located on the inner side of the inner cavity along the longitudinal opening direction of the inner cavity, and a switching line is arranged on the PCB feeder, and the switching line is arranged opposite to the cavity window; a coaxial cable is arranged outside the phase shifter cavity, and a cable core at one end of the coaxial cable is connected to the switching line through the cavity window, and the coaxial cable, the PCB feeder and the phase shifter cavity are electrically conductive. It can be understood that multiple 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, and the part of the metal routing layer not covered by the phase shifting medium contacts the air to form a suspended stripline structure; the switching line of the PCB feed line is arranged opposite to the cavity window, and the metal wall between the upper and lower cavities is used 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, and the cable core at one end thereof is connected to the switching line through the cavity window to achieve electrical conduction, corresponding to the coaxial transmission line; wherein the above-mentioned air microstrip line structure as a transition structure can realize the switching between the suspended stripline and the coaxial transmission line, so that the present application can use the suspended stripline as the phase shifter body, the coaxial transmission line as the port, and the air microstrip line as the connection transition between the two, effectively reducing the energy loss of the signal during transmission, improving the transmission efficiency of the overall system, as well as reducing noise and interference, and improving the signal-to-noise ratio, thereby complementing the advantages of various transmission line forms and having the characteristics of low loss and high efficiency.

[0016] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures particularly pointed out in the description, claims and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

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

[0018] The following further describes the present invention in conjunction with the accompanying drawings and embodiments; Figure 1 is a schematic diagram of the obliquely upward direction of the multi - transmission - line - form - fused phase shifter provided by an embodiment of the present invention; Figure 2 is a schematic diagram of the longitudinal opening direction of the multi - transmission - line - form - fused phase shifter provided by an embodiment of the present invention; Figure 3 is a schematic diagram of the connection between the phase - shifter cavity and the coaxial cable provided by an embodiment of the present invention; Figure 4 is a schematic diagram of the profile blank corresponding to the phase - shifter cavity provided by an embodiment of the present invention; Figure 5 is a partial schematic diagram of the U - shaped wiring groove provided by an embodiment of the present invention; Figure 6 are the top view and cross - sectional view of the phase - shifter cavity provided by an embodiment of the present invention; Figure 7 is a schematic diagram of the PCB feeder provided by an embodiment of the present invention; Figure 8 is a schematic diagram of the phase - shifting medium structure provided by an embodiment of the present invention; Figure 9 is a curve graph of the voltage standing - wave ratio (VSWR) varying with frequency provided by an embodiment of the present invention; Figure 10 is a curve graph of the characteristic impedance (Z0) varying with frequency provided by an embodiment of the present invention.

[0019] Reference numerals: 100, multi - transmission - line - form - fused phase shifter; 1, phase - shifter cavity; 2, PCB feeder; 3, coaxial cable; 4, phase - shifting medium structure; 5, fixed pin; 10, profile blank. Detailed implementation manners

[0020] This part will describe in detail the specific embodiments of the present invention. The preferred embodiments of the present invention are shown in the accompanying drawings. The role of the accompanying drawings is to supplement the description of the text part of the specification, enabling people to intuitively and vividly understand each technical feature and the overall technical solution of the present invention, but it cannot be understood as a limitation to the protection scope of the present invention.

[0021] In the description of the present invention, "several" means one or more, "multiple" means more than two, and understandings such as "greater than", "less than", "exceeding", etc. do not include the present number, and understandings such as "above", "below", "within", etc. include the present number. "Any one" means one or more, and "at least one of the following" and its similar expressions refer to any combination of these items, including any combination of single items or plural items. If there is a description of "first" and "second", it is only for the purpose of distinguishing technical features and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features or implicitly indicating the sequence relationship of the indicated technical features.

[0022] It should be noted that words such as "set", "installed", "connected", etc. in the embodiments of the present invention should be understood in a broad sense, and those skilled in the art can reasonably determine the specific meanings of the above words in the embodiments of the present invention in combination with the specific content of the technical solution. For example, the term "connected" can be a mechanical connection, an electrical connection or can communicate with each other; it can be directly connected or indirectly connected through an intermediate medium.

[0023] It should be noted that the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0024] Currently, the inside of a base station antenna mainly includes key devices such as phase shifters, power dividers, couplers, filters, and combiners. 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 striplines, microstrip lines, coaxial transmission lines, and waveguide designs, etc. The main function of the transmission line is to transfer high-frequency energy from the transmitter to the antenna input end with the minimum loss, or transfer it in the reverse direction to the receiver. Different types of transmission lines play different roles in the design of base station antennas due to their unique physical characteristics and applicable scenarios. However, in actual engineering applications, base station antenna devices designed with 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 civilian field; Although the stripline has low loss, due to its complex structure and great implementation difficulty, its versatility is low; The microstrip line is widely used in civilian base station antennas because of 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 lines in wideband base stations is gradually decreasing. Therefore, to solve the above problems, it is necessary to design a base station antenna device that combines the advantages of multiple transmission line forms to solve various problems faced in the design process of current base station antenna devices.

[0025] Based on this, referring to Figures 1 to 8 , Figure 1 is a schematic diagram of the obliquely upward direction of the multi-transmission line form fusion type phase shifter provided by the embodiment of the present invention;Figure 2 It is a schematic diagram of the longitudinal opening direction of the multi - transmission - line - form fusion phase shifter provided by an embodiment of the present invention; Figure 3 It is a schematic diagram of the connection between the phase - shifter cavity and the coaxial cable provided by an embodiment of the present invention; Figure 4 It is a schematic diagram of the profile blank corresponding to the phase - shifter cavity provided by an embodiment of the present invention; Figure 5 It is a partial schematic diagram of the U - shaped wiring groove provided by an embodiment of the present invention; Figure 6 It is a top view and a cross - sectional view of the phase - shifter cavity provided by an embodiment of the present invention; Figure 7 It is a schematic diagram of the PCB feeder provided by an embodiment of the present invention; Figure 8 It is a schematic diagram of the phase - shifting medium structure provided by an embodiment of the present invention.

[0026] In a first aspect, an embodiment of the present invention provides a multi - transmission - line - form fusion phase shifter 100, including: a phase - shifter cavity 1, including a plurality of inner cavities separated by inner cavity walls, and cavity openings are provided on the sides of the inner cavities; a plurality of PCB feeders 2, inserted into the guide rails located inside the inner cavities along the longitudinal opening direction of the inner cavities, and transfer circuits are provided on the PCB feeders 2, and the transfer circuits are deployed facing the cavity openings; a coaxial cable 3, arranged outside the phase - shifter cavity 1, and the cable core at one end of the coaxial cable 3 is connected to the transfer circuit through the cavity opening, and electrical conduction is achieved among the coaxial cable 3, the PCB feeder 2, and the phase - shifter cavity 1.

[0027] Among them, the phase - shifter cavity 1 is the housing of the entire device, made of a metal material, used to accommodate and protect internal components. The inside of the phase - shifter cavity 1 is divided into a plurality of independent inner cavities, which are separated by inner cavity walls to reduce electromagnetic interference between different signal paths. Cavity openings are provided on the sides of the inner cavities for connecting the coaxial cable 3.

[0028] In some embodiments, the inner cavity walls are metal walls, and the inside of the phase - shifter cavity 1 is divided into a plurality of independent inner cavities by metal walls, such as a first inner cavity and a second inner cavity. These inner cavities provide physical isolation to ensure that the mutual interference between different signal paths is minimized. Cavity openings are provided on the sides of the inner cavities for installing and connecting the coaxial cable 3.

[0029] The PCB feeder 2 is a transmission line on a printed circuit board, used to transmit signals from one point to another. The PCB feeder 2 is inserted into the guide rails located inside the inner cavities along the longitudinal opening direction of the inner cavities to ensure its stability inside the cavity. Transfer circuits are provided on the PCB feeder 2, and these transfer circuits are deployed facing the cavity openings for electrical connection with the coaxial cable 3.

[0030] The coaxial cable 3 is a signal transmission cable having a four-layer structure of a central conductor, an insulating layer, a shielding layer and an outer sheath. The metal shielding layer at one end of the coaxial cable 3 is stripped to expose the internal cable core for welding with the switching line on the PCB feeder 2. The metal shielding layer of the coaxial cable 3 is used to prevent external electromagnetic interference and is fixed to the phase shifter cavity 1 through a U-shaped wiring groove.

[0031] It can be understood that multiple PCB feed lines 2 are inserted into the guide rail located on the inner side of the inner cavity along the longitudinal opening direction of the inner cavity, and the part of the metal routing layer not covered by the phase shifting medium contacts the air to form a suspended stripline structure; the switching line of the PCB feed line 2 is deployed opposite to the cavity window, and the metal wall between the upper and lower 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 on the outside of the phase shifter cavity 1, and the cable core at one end thereof is connected to the switching line through the cavity window to achieve electrical conduction, corresponding to the coaxial transmission line; the above-mentioned air microstrip line structure as a transition structure can realize the switching between the suspended stripline and the coaxial transmission line, so that the present application can use the suspended stripline as the phase shifter body, the coaxial transmission line as the port, and the air microstrip line as the connection transition between the two, effectively reducing the energy loss of the signal during transmission, improving the transmission efficiency of the overall system, as well as reducing noise and interference, and improving the signal-to-noise ratio, thereby complementing the advantages of various transmission line forms and having the characteristics of low loss and high efficiency.

[0032] It can be understood that the suspended stripline serves as the main body of the phase shifter. The suspended stripline is a form of microwave transmission line, in which the signal line is "suspended" in the air or other low dielectric constant media instead of directly contacting the metal cavity. The front and back sides of the substrate of the PCB feed line 2 are provided with the same metal routing layer, and conduction is achieved through multiple metal vias. The part of the metal routing layer not covered by the phase shifting medium contacts the air to form a suspended stripline structure. Air as a medium has a lower dielectric constant, which significantly reduces the energy loss in signal transmission. The suspended stripline avoids direct contact between the signal line and the metal surface, reduces reflection and interference, and improves the purity and efficiency of signal transmission.

[0033] It can be understood that the metal shielding layer is stripped off at one end of the coaxial cable 3 to expose the internal cable core, and is connected to the switching line on the PCB feeder 2 by welding. The switching line on the PCB feeder 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. The air microstrip line serves as a transition structure between the suspended strip line and the coaxial transmission line, ensuring a smooth conversion of the signal from one transmission line form to another, reducing transmission losses, and reducing unnecessary reflections and interference through the switching line and cavity window in the present application, thereby further improving the efficiency of signal transmission.

[0034] In some embodiments, the multi - transmission - line - form fusion phase shifter 100 further includes a plurality of phase - shift medium structures 4 slidably inserted into the inner cavity. The phase - shift medium structure 4 includes upper and lower layers of phase - shift medium layers, and the two layers of phase - shift medium layers are respectively disposed on the upper and lower sides of the corresponding PCB feeder 2. A mating pin is provided between the two layers of phase - shift medium layers, and the mating pin longitudinally slides in the hollowed - out track of the PCB feeder 2 to limit the sliding position of the phase - shift medium structure 4 within the phase - shifter cavity 1.

[0035] Among them, the phase - shift medium structure 4 is a medium for adjusting the signal phase and is made of a low - loss material. The phase - shift medium structure 4 includes upper and lower layers of phase - shift medium layers, which are respectively disposed on the upper and lower sides of the corresponding PCB feeder 2.

[0036] In some embodiments, as Figure 8 shown, the phase - shift medium layer is provided with first rectangular openings and second rectangular openings of different sizes. Hemispherical protrusions are provided on both the upper surface and the lower surface of the phase - shift medium layer. The first rectangular openings and second rectangular openings of different sizes are used to optimize the signal transmission characteristics at different frequency bands. Hemispherical protrusions are provided on both the upper surface and the lower surface of the phase - shift medium layer to reduce the frictional force generated when the phase - shift medium slides in the cavity.

[0037] It can be understood that the phase - shift medium structure 4 can be injection - molded using a low - loss PPE material with a dielectric constant of 4.4 and a tangent angle loss of 0.0008. Two first rectangular openings 4b1 and second rectangular openings 4b2 with different sizes are deployed on the phase - shift medium structure 4, which can ensure good wide - band matching during the sliding of the phase - shift medium. Hemispherical protrusions 4a are provided on both the upper surface and the lower surface of the phase - shift medium, and the hemispherical protrusions 4a can reduce the frictional force generated when the phase - shift medium structure 4 slides in the cavity. In addition, a mating pin 4c is provided between the upper and lower layers of the phase - shift medium, and the mating pin 4c can longitudinally slide in the hollowed - out track 2d of the PCB feeder 2 to prevent the phase - shift medium of the phase shifter from falling off during the sliding process in the cavity.

[0038] In some embodiments, the front and back sides of the substrate of the PCB feeder 2 are both provided with the same metal trace layer, and conduction is achieved through a plurality of metal vias. The part of the metal trace layer not covered by the phase - shift medium layer contacts air to form a suspended stripline structure. It can be understood that the PCB feeder 2 is inserted into the guide rail 1g located in the inner cavity along the longitudinal opening direction of the cavity. Then, the PCB feeder 2 and the inner cavity form a suspended stripline, and the transmission medium of the metal trace layer not covered by the phase - shift medium structure 4 is air. Thus, except for the area not covered by the phase - shift medium structure 4 in the entire cavity, other partial areas can have lower transmission losses.

[0039] In some embodiments, as Figure 4As shown, the phase shifter cavity 1 is integrally pultruded from a profile blank 10 made of metal aluminum. 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 from top to bottom. Corresponding U-shaped wiring grooves are mirror-deployed on 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 blank and are integrated with the outer cavity. The U-shaped wiring is used to fix the coaxial cable 3. Among them, the phase shifter cavity 1 of the multi-transmission-line form fusion type phase shifter 100 is a blank made of metal aluminum by integral pultrusion molding, which is open in its longitudinal direction to facilitate the realization of the pultrusion process and is closed in other directions. When a feeder is deployed inside the cavity, the closed outer cavity can act as the function of a reference ground. For example, Figure 4 In the profile blank 10 of the metal aluminum, two inner cavities 10a and 10b are deployed up and down, and two U-shaped wiring grooves 10c and 10d are respectively deployed on the side of the outer cavity. The U-shaped wiring grooves are deployed perpendicular to the side of the blank. One side of the U-shaped wiring groove is integrated with the outer cavity of the blank, minimizing the contact area between the U-shaped wiring groove and the cavity itself to reduce the heat dissipation of the metal cavity during welding and improve the welding quality. The two U-shaped wiring grooves 10c and 10d are mirror-deployed corresponding to the two inner cavities 10a and 10b respectively, as Figure 6 shown, guide rails 1g protruding 1 mm from the inner cavity wall are respectively deployed on the left and right sides of the sides of the inner cavities 10a and 10b.

[0040] In some embodiments, as Figure 7 shown, the PCB feeder 2 uses a low-loss PTFE material as the substrate 2a, the substrate thickness is 0.762 mm, its dielectric constant is 2.2, and the tangent angle loss is 0.0009. The same metal wiring layers 2b1 and 2b2 are provided on the front and back of the substrate 2a. The wiring layers 2b1 and 2b2 are conducted through multiple metal vias 2c. Multiple metal vias 2c are deployed between the two wiring layers, strengthening the overall hardness of the PCB feeder 2 while the upper and lower wiring layers are conducted to form a whole, which is equivalent to increasing the thickness of the feeder, reducing the heat loss. The surface of the metal wiring layer has undergone an immersion silver process, and the immersion silver thickness is 0.005 mm. The immersion silver process improves the conductivity of the metal wiring layer and has a moderate cost, further reducing the transmission loss.

[0041] In some embodiments, the cavity windowing includes a top window and a side window respectively provided on the top surface and the side surface of the phase shifter cavity 1. The top window and the side window are penetrated, the side window is smaller than the top window, and U-shaped wiring grooves are respectively provided on the left and right sides of the side window, and a preset gap is left between the U-shaped wiring grooves on the left and right sides.

[0042] Specifically, as Figure 5As shown, two windows of different sizes are arranged on the top and side of the cavity, the top window is located on the top of the cavity, the side window is located on the side of the cavity, the top window and the side window are connected, wherein the side window is smaller than the top window, and the side window has two structural features, the main window 1b1 and the chamfer 1b2. A 10mm long U-shaped wiring groove 1c is arranged on the left and right sides of the side window, respectively, and a gap 1d is left between the U-shaped wiring grooves on the left and right sides.

[0043] In some embodiments, the metal shielding layer is peeled off at one end of the coaxial cable 3 connected to the switching line, and the metal shielding layer and the cable medium are bent 90° along the junction of the metal shielding layer and the cable medium, and a preset length of the cable core is peeled off at the top of the cable medium, and the cable core is welded to the switching line; specifically, 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 velocity of 80%. The metal shielding layer is stripped off at one end of the coaxial cable 3, and the metal shielding layer and the cable medium are bent 90° along the junction. A 3mm length of the cable core is stripped off at the top of the cable medium.

[0044] In some embodiments, the coaxial cable 3 passes through the top window and the side window, the cable core of the coaxial cable 3 is connected to the PCB feeder 2 by welding to form a tin pile, the metal shielding layer of the coaxial cable 3 is supported by the U-shaped wiring groove on the side of the cavity, and the metal shielding layer of the coaxial cable 3 is welded to the U-shaped wiring groove by adding tin to ensure electrical conduction.

[0045] In some embodiments, 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, and the cable core is placed on the switching line 2e of the PCB feeder 2. The tin pile 3a is formed by welding to conduct with the PCB feeder 2. The metal shielding layer 3c of the coaxial cable 3 can be supported by the U-shaped wiring groove 1c on the side of the cavity. The metal shielding layer 3c of the coaxial cable 33 can be welded to the U-shaped wiring groove 1c by adding tin to the U-shaped wiring groove 1c, thereby realizing the electrical conduction between the coaxial cable 3 and the phase shifter. The coaxial cable 3 can be deployed in two directions: left and right.

[0046] Among them, 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 of the metal cavity has a chamfer 1b2, which can clamp the medium 3b of the coaxial cable 33, so that the coaxial cable 3 is not easy to fall off the phase shifter 100. At the same time, it can also avoid introducing other auxiliary structural parts to achieve the fixation of the coaxial cable 3, reducing the intermodulation failure points.

[0047] In some embodiments, the multi-transmission line fusion phase shifter 100 also includes a fixing pin arranged on the top of the phase shifter cavity 1, and the fixing pin passes through the special-shaped hole on the top surface of the phase shifter cavity 1, the circular hole on the substrate of the PCB feed line 2, and the circular holes on the inner cavity wall and the bottom surface of the phase shifter cavity 1, and the circular protrusion on the fixing pin is embedded in the circular hole on the top surface of the phase shifter cavity 1 by rotating 90° to fix the PCB feed line 2, so that the PCB feed line 2 will not shake in the cavity, thereby improving the stability of the PCB feed line 2.

[0048] In some embodiments, Figure 6 As shown, a circular hole 1f and a combination hole 1e are provided on the top surface of the cavity. The circular hole 1f is only arranged on the top surface of the phase shifter cavity 1, and the combination hole 1e runs through the entire cavity. It can be understood that the circular 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 both provided with circular holes.

[0049] In summary, part of the metal routing layer of the PCB feed line 2 in the present application is not covered by a phase-shifting medium and is in direct contact with the air to form a suspended stripline structure. Air, as a low dielectric constant medium, significantly reduces the energy loss in signal transmission. Rectangular windows of different sizes on the phase-shifting medium layer optimize the signal transmission characteristics in different frequency bands, further reducing the transmission loss. Using air as the main transmission medium reduces the energy loss of the signal during transmission, and improves the transmission efficiency of the overall system. The low-loss characteristic helps to maintain signal integrity, reduce noise and interference, and thus improve the signal-to-noise ratio. Furthermore, the present application deploys the window opening directly opposite the cavity through the switching line, achieves electrical conduction through welding, reduces unnecessary reflections and interference, and forms an air microstrip line transition structure. Through the air microstrip line transition structure, a smooth transition between the suspended stripline and the coaxial transmission line can be achieved, ensuring efficient transmission of the signal from one transmission line form to another, and realizing the conversion of the three transmission line forms.

[0050] In addition, the conversion between the three transmission line forms in the present application does not introduce additional structural parts to assist in fixation, so there are fewer electrical failure points and the intermodulation is stable.

[0051] In some embodiments, the present application can adopt a coaxial cable 3 with a standard impedance of 50 ohms to be suitable for various application scenarios, and allow the coaxial cable 3 to be deployed in the left and right directions, so that the present application can use a suspended strip line as the phase shifter body, a 50 ohm low-loss coaxial transmission line as the port, and an air microstrip line as the connection transition between the two, avoiding the shortcomings of various transmission lines in traditional solutions, integrating three different transmission line forms together, realizing the design of antenna devices, and having versatility and expansibility.

[0052] refer to Figures 9 to 10 ,Figure 9 It is a curve graph showing the variation of voltage standing wave ratio (VSWR) with frequency provided by an embodiment of the present invention; Figure 10 It is a curve graph showing the variation of characteristic impedance (Z0) with frequency provided by an embodiment of the present invention; Figure 9 In [graph], the horizontal axis (X-axis): represents the frequency range, with the unit of 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 [graph], the horizontal axis (X-axis): represents the frequency range, with the unit of GHz (gigahertz), the vertical axis (Y-axis): represents the characteristic impedance value, with the unit of ohm (Ω), and it is stable at 50 ohms; it can be seen that in this application, the transition structure between the suspended stripline and the coaxial transmission line is completed with an air microstrip line transition structure, that is, the suspended stripline is used as the main body of the phase shifter, the 50-ohm low-loss coaxial transmission line is used as the port, and the air microstrip line is used as the connection transition between the two. Through the corresponding specific detail dimension settings in the above embodiments, a communication effect is achieved where the standing wave is less than 1.1 within the working frequency range of 1690 - 2690 MHz, and the output port impedance value is stable at 50 ohms, having universality.

[0053] In a second aspect, an embodiment of the present invention provides a base station antenna device, including the multi-transmission-line form fusion type phase shifter according to any one of the embodiments in the first aspect.

[0054] The above has described the embodiments of the present invention in detail with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those of ordinary skill in the art, various changes can be made without departing from the gist of the present invention.

Claims

1. A multi - transmission - line - form fusion phase shifter, characterized in that, include: The phase shifter cavity comprises a plurality of inner cavities separated by inner cavity walls, and the side of the inner cavity is provided with a cavity window; A plurality of PCB feed lines are inserted into the guide rail located inside the inner cavity along the longitudinal opening direction of the inner cavity, and a switching circuit is arranged on the PCB feed lines, and the switching circuit is arranged facing the window of the cavity; A coaxial cable is arranged outside the phase shifter cavity, a cable core at one end of the coaxial cable is connected to the switching line through the cavity window, and electrical conduction is established between the coaxial cable, the PCB feeder and the phase shifter cavity.

2. The multi-transmission-line form fusion type phase shifter according to claim 1, characterized in that The multi-transmission line fusion phase shifter also includes a plurality of phase-shifting medium structures slidably inserted into the inner cavity, the phase-shifting medium structure includes an upper and lower phase-shifting medium layer, the two phase-shifting medium layers are respectively arranged on the upper and lower sides of the corresponding PCB feeder, and a mating pin is arranged between the two phase-shifting medium layers, and the mating pin slides longitudinally in the hollow track of the PCB feeder to limit the sliding position of the phase-shifting medium structure in the phase shifter cavity.

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

4. The multi-transmission-line form fusion type phase shifter according to claim 2, characterized in that, The front and back sides of the substrate of the PCB feeder are both provided with the same metal routing layer, and conduction is achieved through multiple metal vias. The part of the metal routing layer not covered by the phase-shifting dielectric layer contacts the air to form a suspended stripline structure.

5. The multi-transmission line form fusion type phase shifter according to claim 1, characterized in that The phase shifter cavity is formed by integral pultrusion of metal aluminum material. The inner cavity of the phase shifter cavity includes a first inner cavity and a second inner cavity separated by an inner cavity wall. The outer sides of the first inner cavity and the second inner cavity are mirror-imaged with corresponding U-shaped wiring grooves. The U-shaped wiring grooves are arranged perpendicular to the sides of the embryo body and are connected to the outer cavity as a whole. The U-shaped wiring is used to fix the coaxial cable.

6. The multi - transmission - line - form - fusion phase shifter according to claim 5, wherein The cavity window comprises a top window and a side window respectively provided on the top surface and the 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 U-shaped wiring grooves are respectively provided on the left and right sides of the side window, and a preset gap is left between the U-shaped wiring grooves on the left and right sides.

7. The multi-transmission line form fusion type phase shifter according to claim 6, wherein The metal shielding layer is stripped off at one end of the coaxial cable connected to the switching line, and the cable is bent 90° along the junction between the metal shielding layer and the cable medium. The cable core of a preset length is stripped off at the top of the cable medium, and the cable core is welded to the switching line.

8. The multi-transmission line form fusion type phase shifter according to claim 7, characterized in that The coaxial cable passes through the top window and the side window, the cable core of the coaxial cable is connected to the PCB feeder by welding to form a tin pile, 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 welded to the U-shaped wiring groove by adding tin to ensure electrical conduction.

9. The multi - transmission - line form - fusion phase shifter according to claim 1, wherein, The multi - transmission - line - form - fusion phase shifter further includes a fixed pin disposed 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 round hole on the PCB feeder substrate, the inner cavity wall, and the round hole on the bottom surface of the phase shifter cavity, and the circular bump on the fixed pin is embedded into the round hole on the top surface of the phase shifter cavity by rotating 90° to fix the PCB feeder.

10. A base station antenna device, characterized in that, It includes the multi - transmission - line - form - fusion phase shifter according to any one of claims 1 to 9.

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