An antenna tuner based on internal damping structure

Abstract

The application discloses an antenna tuner based on an internal damping structure, which comprises a cabinet, a vibration isolator, a metal mounting plate, a super-flexible shielding channel and an internal functional module, wherein the cabinet is hung on an aviation platform, one vibration isolator is installed on each of four supporting corners in the cabinet, and the metal mounting plate is installed in the cabinet through the four vibration isolators; the internal functional module is installed on the metal mounting plate, and the internal functional module is connected with external interfaces on the cabinet through the super-flexible shielding channel. The application realizes damping of each functional module of the antenna tuner, has high integration, strong anti-vibration capacity, excellent electromagnetic compatibility, is convenient to install, has strong environmental adaptability, is high in reliability and is suitable for use requirements of a new aviation platform on air equipment.

Description

Technical Field

[0001] This invention relates to the field of communication equipment structure and electronic circuit technology, and in particular to an antenna tuner based on an internal vibration reduction structure. Background Technology

[0002] An antenna tuner is an impedance matching network connecting a transmitter and an antenna. It achieves impedance matching between the shortwave transmitter and antenna, ensuring maximum radiated power at any frequency. It is widely used in ground-based, vehicle-mounted, shipborne, and airborne shortwave radios. The internal matching network of an antenna tuner typically consists of relatively heavy discrete components such as relay groups, inductor groups, and capacitor groups. Since vehicle-mounted, shipborne, and airborne antenna tuners operate in random vibration environments, without appropriate vibration damping measures, the equipment may experience faults such as solder joint detachment, pin breakage, and loose connections.

[0003] Because airborne antenna tuners need to meet requirements such as wide operating range, high vibration levels, small size, and light weight, only vacuum relays can be selected for the matching network relay group. These vacuum relays have a wide temperature range, extremely high dielectric withstand voltage, and low contact resistance, performing excellently in high-frequency and high-power applications. However, due to the high levels and long duration of vibrations on aviation platforms, and the poor high-frequency vibration resistance of vacuum relays, breakage at the connection between the ceramic cavity and the metal housing support can occur during vibration testing. Therefore, existing airborne antenna tuners typically employ external vibration isolators for vibration reduction. With the increasing demands for high integration in communication systems on aviation platforms, traditional antenna tuners can no longer meet the installation and usage requirements of aviation platforms. Summary of the Invention

[0004] The purpose of this invention is to provide an antenna tuner based on an internal vibration reduction structure that has strong vibration resistance, good mechanical properties, high electromagnetic compatibility, high reliability, and strong environmental adaptability, making it suitable for use on various platforms and in multiple scenarios.

[0005] The technical solution to achieve the purpose of this invention is: an antenna tuner based on an internal vibration reduction structure, including a chassis, a vibration isolator, a metal mounting plate, an ultra-flexible shielding channel, and internal functional modules;

[0006] The chassis is mounted on the side of the aviation platform. A vibration isolator is installed on each of the four support corners inside the chassis. The metal mounting plate is installed inside the chassis through the four vibration isolators. The internal functional modules are mounted on the metal mounting plate and are connected to the external interfaces on the chassis through ultra-flexible shielded channels.

[0007] Furthermore, the chassis includes a shell, an upper cover plate, and a lower cover plate. The shell, upper cover plate, and lower cover plate are all equipped with local reinforcing ribs to reduce weight while ensuring rigidity. The upper and lower side walls of the shell are respectively provided with mounting grooves, and double-peak composite conductive rubber strips are installed. After being pressed together by the upper cover plate and the lower cover plate, electromagnetic shielding and salt spray corrosion resistance are achieved.

[0008] Furthermore, a vibration isolator is installed at each of the four support corners inside the chassis housing. The metal mounting plate is installed on the vibration isolator using M4 screws. The internal functional modules are installed on the metal mounting plate. The vibration isolators absorb vibration and impact energy to reduce the vibration of the internal functional modules, ensuring that the equipment weighing 4~5kg meets the vibration environment requirements of 5Hz~2000Hz, vibration magnitude not less than 12g, and each of the three orthogonal axes not less than 40h, for a total of 120h.

[0009] Furthermore, the vibration isolator is a metal vibration isolator without resonance peak, comprising a housing, a column, a base plate, a slider, a cylindrical sleeve, a collar, a first circular plate, a second circular plate, a first compression spring, a second compression spring, a spring retainer, and stainless steel hollow rivets.

[0010] A column is mounted on the central axis of the housing. The top of the column passes through an opening in the center of the housing and enters the housing. A first compression spring, a first circular plate, a cylindrical sleeve, and a second circular plate are sequentially installed on the column inside the housing. A collar is then installed at the end of the column to press the first compression spring, the first circular plate, the cylindrical sleeve, and the second circular plate onto the column. A second compression spring is then installed outside the collar. Finally, the base plate and the housing are assembled together using stainless steel hollow rivets. A spring retainer and a slider are installed between the outer side of the cylindrical sleeve and the inner wall of the housing. The slider is installed outside the spring retainer.

[0011] The shell, column, base plate, first circular plate, second circular plate and hollow rivet are made of 316L stainless steel, the first compression spring, second compression spring and spring retainer are made of stainless steel wire, the cylindrical sleeve is made of glass fiber filled polytetrafluoroethylene rod, and the slider is made of tin bronze powder-graphite filled PTFE.

[0012] The first and second compression springs convert the energy generated during the equipment vibration process into the potential energy of the first and second compression springs, which is then gradually released under the restoring force of the first and second compression springs, absorbing the vibration energy. During the movement, the slider expands under the action of the spring retainer, and the friction between the outer wall of the slider and the inner wall of the housing generates damping, converting some of the elastic potential energy into heat energy. The first and second compression springs are conical helical springs to prevent resonance.

[0013] Furthermore, the internal functional modules include an interface board, a voltage regulator board, a control board, a detection board, a relay group, an inductor group, a capacitor board, and a network baseboard;

[0014] The detection board, relay group, inductor group, capacitor board and network base plate are all directly mounted on the metal mounting plate and form a matching detection network through signal cross-linking;

[0015] The interface board consists of a transient voltage suppression circuit, a surge suppression circuit, and a level conversion circuit, which realizes interface lightning indirect effect protection, power supply compatibility protection, common-mode noise suppression, and RS485 asynchronous serial port level conversion functions.

[0016] The voltage regulator board uses a linear voltage regulator, which is installed close to the surface of the chassis and coated with thermal grease. The voltage regulator board uses a three-terminal voltage regulator to convert the input +28VDC to +5VDC to provide power to the control board and the matching detection network.

[0017] The control board is based on an MCU circuit and, according to the frequency, tuning commands, and status query commands issued by the system, realizes functions such as communication with the system, control of the vector impedance detection circuit, control of the tuning power generation circuit, control of the matching network, and storage of tuning parameters.

[0018] Furthermore, the detection board uses a directional coupler to sample the tuned radio frequency signal in the frequency range of 2MHz to 45MHz, and sends the voltage and current sampling signals to the control unit for impedance measurement; the directional coupler has 45 turns, an inductance of 80μH to 180μH at 2MHz, a standing wave ratio S11 ≤ 1.2, and a coupling degree S21 = 33dB ± 1dB;

[0019] The relay group uses high-voltage ceramic vacuum relays with a peak operating voltage of 10kVDC and an effective current carrying capacity of 25ADC.

[0020] The inductor group is made of air-core coil winding;

[0021] The capacitor bank on the capacitor plate is selected as a radio frequency high-Q capacitor.

[0022] Furthermore, the interface board, control board, and detection board are all installed in a fully shielded independent metal cavity to ensure electromagnetic compatibility and tuning performance. The interface board, control board, and network base plate are connected to the network base plate via blind mating printed circuit connectors, and all cross-linking signals are filtered. The connection between the control board and the network base plate is designed with a metal shielding channel according to the connector size, and a solder mask window is made on the top layer of the corresponding contact surface on the network base plate. After being fixed and tightened with screws, full shielding is achieved. The interface between the interface board and the network base plate uses a micro rectangular filter electrical connector. Shielding and filtering are achieved by increasing the contact area between the connector's metal flange shell and the shielding cover, and by using conductive pads.

[0023] Furthermore, the ultra-flexible shielding channel includes a wave-damping sleeve, a shielding tail clip, a metal shielding tube, an external interface connector, and a clamp;

[0024] The power lines and asynchronous serial bus between the interface board and the external interface are fully shielded 360° using an ultra-flexible shielding channel composed of a wave-shielding sleeve, a shielded tail clip, and a metal shielding tube. Meanwhile, the external interface uses a C-type circuit-type square flange filter connector, and capacitors of different capacities are combined according to the signal characteristics to achieve filtering, shielding, and grounding, preventing common-mode interference and stray noise from the power lines and asynchronous serial bus from entering the RF path.

[0025] Furthermore, the anti-surge sleeve is made of tin-plated copper foil wire; the external interface uses a threaded shielding tail clip with a maximum outer diameter of 20mm and an internal thread of M18×1-6H-6; the flexible cable interface of the interface board uses a metal shielding tube with a flange structure, with a flange diameter of 18mm and a thickness of 1.5mm; a positioning flange is set on the shielding tail clip and the metal shielding tube 7mm from the tail, with a flange diameter of 17.5mm and a thickness of 1mm; the clamp is a circular clamp with an outer diameter of 17.5mm, an inner diameter of 15.5mm, and a thickness of 5mm; the shielding tail clip, shielding tube, and clamp housing are all made of aluminum alloy with a 15μm electroless nickel plating on the surface.

[0026] Furthermore, before installation, prepare anti-surge sleeves of matching length according to the distance between the shielding tail clip of the external interface connector and the metal shielding tube of the interface board. During installation, first fix the external interface connector to the chassis housing with four M3 screws, then screw the shielding tail clip into the tail end of the external interface connector, then put the anti-surge sleeve onto the flexible cable and wrap it 7mm around the shielding tail clip, then press the clamp into the shielding tail clip, and finally weld the shielding tail clip, clamp, and anti-surge sleeve together to achieve a 360° ring connection and reliably ground to the cavity; on the other end, use two M2.5 screws to press the flange of the metal shielding tube with flange structure onto the interface board, then put the anti-surge sleeve onto the metal shielding tube and wrap it 7mm around, then press the clamp into the metal shielding tube, and finally weld the metal shielding tube, clamp, and anti-surge sleeve together to achieve a 360° ring connection and reliably ground to the cavity, ultimately achieving a full shielding effect for all interface signals.

[0027] Compared with the prior art, the present invention has the following significant advantages: (1) By setting up a vibration damping device inside the device, the vibration damping of each functional module of the antenna tuner is realized. It has high integration and strong vibration resistance, and is suitable for use in various platforms and scenarios. (2) The ultra-flexible shielding channel composed of tin-plated copper foil wire anti-wave sleeve, shielding tail clip and shielding tube is used to realize the rigid-flexible connection of the internal and external interfaces. At the same time, the sensitive modules are all placed in independent cavities and can be blindly plugged in to achieve connection. It can work reliably in harsh mechanical environments and has excellent electromagnetic compatibility performance. It is easy to install, has strong environmental adaptability, and high reliability. It is suitable for the use of air-use equipment on new aviation platforms. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of an antenna tuner based on an internal vibration reduction structure according to the present invention.

[0029] Figure 2 This is a schematic diagram of the installation structure of the vibration isolator in this invention.

[0030] Figure 3 This is a schematic diagram of the vibration isolator in this invention.

[0031] Figure 4 This is a schematic diagram of the ultra-flexible shielding channel in this invention.

[0032] Figure 5 This is a schematic diagram of the structure of the shielding tail clip, shielding tube, and clamp in this invention.

[0033] Figure 6 This is a schematic diagram of the structure of the control board shielding cavity in this invention. Detailed Implementation

[0034] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0035] like Figure 1 As shown, the present invention provides an antenna tuner based on an internal vibration reduction structure, comprising a chassis, a vibration isolator, a metal mounting plate, an ultra-flexible shielding channel, and an internal functional module.

[0036] The chassis is mounted on the side of the aviation platform. A vibration isolator is installed on each of the four support corners inside the chassis. The metal mounting plate is installed inside the chassis through the four vibration isolators. The internal functional modules are mounted on the metal mounting plate and are connected to the external interfaces on the chassis through ultra-flexible shielded channels.

[0037] As a specific example, the chassis includes a shell, an upper cover plate, and a lower cover plate. The shell, upper cover plate, and lower cover plate are all equipped with local reinforcing ribs to reduce weight while ensuring rigidity. The upper and lower side walls of the shell are respectively provided with mounting grooves, and double-peak composite conductive rubber strips are installed. After being pressed together by the upper cover plate and the lower cover plate, electromagnetic shielding and salt spray corrosion resistance are achieved.

[0038] As a specific example, such as Figure 2 As shown, a vibration isolator is installed on each of the four support corners inside the chassis. The metal mounting plate is installed on the vibration isolator using M4 screws. The internal functional modules are installed on the metal mounting plate. The vibration isolator absorbs vibration and impact energy to reduce the vibration of the internal functional modules. This ensures that the equipment weighing 4~5kg meets the vibration environment requirements of 5Hz~2000Hz, vibration magnitude not less than 12g, and 120h for each of the three orthogonal axes for a total of 40h.

[0039] As a specific example, such as Figure 3 As shown, the vibration isolator is a metal vibration isolator without resonance peak, which consists of a shell, column, base plate, slider, cylindrical sleeve, collar, first circular plate, second circular plate, first compression spring, second compression spring, spring retainer and stainless steel hollow rivets.

[0040] A column is mounted on the central axis of the housing. The top of the column passes through an opening in the center of the housing and enters the housing. A first compression spring, a first circular plate, a cylindrical sleeve, and a second circular plate are sequentially installed on the column inside the housing. A collar is then installed at the end of the column to press the first compression spring, the first circular plate, the cylindrical sleeve, and the second circular plate onto the column. A second compression spring is then installed outside the collar. Finally, the base plate and the housing are assembled together using stainless steel hollow rivets. A spring retainer and a slider are installed between the outer side of the cylindrical sleeve and the inner wall of the housing. The slider is installed outside the spring retainer.

[0041] The shell, column, base plate, first circular plate, second circular plate and hollow rivet are made of 316L stainless steel, the first compression spring, second compression spring and spring retainer are made of stainless steel wire, the cylindrical sleeve is made of glass fiber filled polytetrafluoroethylene rod, and the slider is made of tin bronze powder-graphite filled PTFE.

[0042] The first and second compression springs convert the energy generated during equipment vibration into potential energy, which is then gradually released under the restoring force of the first and second compression springs, reducing the transmission and diffusion of vibration energy, absorbing vibration energy, and lowering the vibration level. During movement, the slider expands under the action of the spring retainer, and friction between the outer wall of the slider and the inner wall of the housing generates damping, converting some elastic potential energy into heat energy. The first and second compression springs are conical helical springs, which have greater lateral stability and can effectively prevent resonance.

[0043] The vibration isolator has a nominal load of 1kg, a load range of 0.6 to 1.2kg, a rated load static deformation of 1mm, a natural frequency of 15Hz, a limit displacement of 2mm, a resonance transmissibility of no more than 2, and a single unit weight of no more than 0.1kg.

[0044] As a specific example, the internal functional modules include an interface board, a voltage regulator board, a control board, a detection board, a relay group, an inductor group, a capacitor board, and a network baseboard;

[0045] The detection board, relay group, inductor group, capacitor board and network base plate are all directly mounted on the metal mounting plate and form a matching detection network through signal cross-linking;

[0046] The interface board consists of a transient voltage suppression circuit, a surge suppression circuit, and a level conversion circuit, which realizes interface lightning indirect effect protection, power supply compatibility protection, common-mode noise suppression, and RS485 asynchronous serial port level conversion functions.

[0047] The voltage regulator board uses a linear voltage regulator, which generates a lot of heat. It is installed close to the surface of the chassis and coated with thermal grease. It can work normally in a high-temperature environment of 70°C by using natural heat dissipation. The voltage regulator board uses a three-terminal voltage regulator to convert the input +28VDC to +5VDC to provide power to the control board and the matching detection network.

[0048] The control board is based on an MCU circuit and, according to the frequency, tuning commands, and status query commands issued by the system, realizes functions such as communication with the system, control of the vector impedance detection circuit, control of the tuning power generation circuit, control of the matching network, and storage of tuning parameters.

[0049] As a specific example, the detection board uses a directional coupler to sample the tuned radio frequency signal in the frequency range of 2MHz to 45MHz, and sends the voltage and current sampling signals to the control unit for impedance measurement; the directional coupler has 45 turns, an inductance of 80μH to 180μH at 2MHz, a standing wave ratio S11 ≤ 1.2, and a coupling degree S21 = 33dB ± 1dB;

[0050] The relay group uses high-voltage ceramic vacuum relays with a peak operating voltage of 10kVDC and an effective current carrying capacity of 25ADC.

[0051] The inductor group is made of air-core coils, which have high Q value and low loss. The inductance changes very little when there is a large current or drastic change in ambient temperature.

[0052] The capacitor bank on the capacitor board is made of radio frequency high-Q capacitors, which have high Q value, low ESR, low loss and high capacitance stability.

[0053] As a specific example, the interface board, control board, and detection board are all installed in a fully shielded independent metal cavity to ensure electromagnetic compatibility and tuning performance. The interface board and control board are blind-mating connected to the network baseboard via printed circuit connectors, and all cross-linking signals are filtered. A metal shielding channel is designed at the connection point between the control board and the network baseboard according to the connector size. Simultaneously, a solder mask window is created on the top layer of the corresponding contact surface on the network baseboard, and full shielding is achieved after being secured with screws. Figure 6 As shown; the interface board and network baseboard interfaces use micro rectangular filter electrical connectors, which achieve shielding and filtering by increasing the contact area between the connector's metal flange shell and the shielding cover and using conductive pads.

[0054] As a specific example, such as Figure 4 , Figure 5 As shown, the ultra-flexible shielding channel includes a wave-damping sleeve, a shielding tail clip, a metal shielding tube, an external interface connector, and a clamp.

[0055] The power lines and asynchronous serial bus between the interface board and the external interface are fully shielded by an ultra-flexible shielding channel consisting of a wave-proof sleeve, a shielded tail clip, and a metal shielding tube. Meanwhile, the external interface uses a C-type circuit square flange filter connector. Different capacitances are combined according to the signal characteristics to achieve filtering, shielding, and grounding, preventing common-mode interference and stray noise from the power lines and asynchronous serial bus from entering the radio frequency path.

[0056] The anti-surge sleeve is made of tin-plated copper foil wire; the external interface uses a threaded shielding tail clip with a maximum outer diameter of 20mm and an internal thread of M18×1-6H-6; the flexible cable interface of the interface board uses a metal shielding tube with a flange structure, with a flange diameter of 18mm and a thickness of 1.5mm; a positioning flange is set on the shielding tail clip and the metal shielding tube 7mm from the tail, with a flange diameter of 17.5mm and a thickness of 1mm; the clamp is a circular clamp with an outer diameter of 17.5mm, an inner diameter of 15.5mm, and a thickness of 5mm; the shielding tail clip, shielding tube, and clamp housing are all made of aluminum alloy with a 15μm electroless nickel plating on the surface;

[0057] Before installation, prepare a surge protector of appropriate length based on the distance between the shielding tail clip of the external interface connector and the metal shielding tube of the interface board. During installation, first fix the external interface connector to the chassis housing with four M3 screws. Then, screw the shielding tail clip into the tail end of the external interface connector. Next, put the surge protector onto the flexible cable and wrap it 7mm around the shielding tail clip. Then, press the clamp into the shielding tail clip. Finally, weld the shielding tail clip, clamp, and surge protector together to achieve a 360° ring connection and reliably ground the cavity. On the other end, use two M2.5 screws to press the flange of the metal shielding tube with flange structure onto the interface board. Then, put the surge protector onto the metal shielding tube and wrap it 7mm around the metal shielding tube. Then, press the clamp into the metal shielding tube. Finally, weld the metal shielding tube, clamp, and surge protector together to achieve a 360° ring connection and reliably ground the cavity. Ultimately, this achieves a complete shielding effect for all interface signals.

[0058] As a specific example, the external interface connector adopts a flange-type screw-sleeve self-locking coaxial connector to achieve shielding, grounding, and screw-sleeve locking to prevent loosening.

[0059] The above are merely preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. An antenna tuner based on an internal vibration damping structure, characterized in that, This includes the chassis, vibration isolators, metal mounting plates, ultra-flexible shielding channels, and internal functional modules; The chassis is mounted on the side of the aviation platform. A vibration isolator is installed on each of the four support corners inside the chassis. The metal mounting plate is installed inside the chassis through the four vibration isolators. The internal functional modules are mounted on the metal mounting plate and are connected to the external interfaces on the chassis through ultra-flexible shielded channels.

2. The antenna tuner based on an internal vibration reduction structure according to claim 1, characterized in that, The chassis includes a shell, an upper cover plate, and a lower cover plate. The shell, upper cover plate, and lower cover plate are all reinforced with local ribs to reduce weight while ensuring rigidity. The upper and lower side walls of the shell are respectively provided with mounting grooves and double-peak composite conductive rubber strips are installed. After being pressed together by the upper cover plate and the lower cover plate, electromagnetic shielding and salt spray corrosion resistance are achieved.

3. The antenna tuner based on an internal vibration reduction structure according to claim 1, characterized in that, One vibration isolator is installed at each of the four support corners inside the chassis. The metal mounting plate is installed on the vibration isolator with M4 screws. The internal functional modules are installed on the metal mounting plate. The vibration isolators absorb vibration and impact energy to reduce the vibration of the internal functional modules, ensuring that the equipment weighing 4~5kg meets the vibration environment requirements of 5Hz~2000Hz, vibration magnitude not less than 12g, and not less than 40h for each of the three orthogonal axes, for a total of 120h.

4. The antenna tuner based on an internal vibration reduction structure according to claim 1, characterized in that, The vibration isolator is a metal vibration isolator without resonance peak, comprising a housing, a column, a base plate, a slider, a cylindrical sleeve, a collar, a first circular plate, a second circular plate, a first compression spring, a second compression spring, a spring retainer, and stainless steel hollow rivets. A column is mounted on the central axis of the housing. The top of the column passes through an opening in the center of the housing and enters the housing. A first compression spring, a first circular plate, a cylindrical sleeve, and a second circular plate are sequentially installed on the column inside the housing. A collar is then installed at the end of the column to press the first compression spring, the first circular plate, the cylindrical sleeve, and the second circular plate onto the column. A second compression spring is then installed outside the collar. Finally, the base plate and the housing are assembled together using stainless steel hollow rivets. A spring retainer and a slider are installed between the outer side of the cylindrical sleeve and the inner wall of the housing. The slider is installed outside the spring retainer. The shell, column, base plate, first circular plate, second circular plate and hollow rivet are made of 316L stainless steel, the first compression spring, second compression spring and spring retainer are made of stainless steel wire, the cylindrical sleeve is made of glass fiber filled polytetrafluoroethylene rod, and the slider is made of tin bronze powder-graphite filled PTFE. The first and second compression springs convert the energy generated during the equipment vibration process into the potential energy of the first and second compression springs, which is then gradually released under the restoring force of the first and second compression springs, absorbing the vibration energy. During the movement, the slider expands under the action of the spring retainer, and the friction between the outer wall of the slider and the inner wall of the housing generates damping, converting some of the elastic potential energy into heat energy. The first and second compression springs are conical helical springs to prevent resonance.

5. The antenna tuner based on an internal vibration reduction structure according to claim 1, characterized in that, The internal functional modules include an interface board, a voltage regulator board, a control board, a detection board, a relay group, an inductor group, a capacitor board, and a network baseboard; The detection board, relay group, inductor group, capacitor board and network base plate are all directly mounted on the metal mounting plate and form a matching detection network through signal cross-linking; The interface board consists of a transient voltage suppression circuit, a surge suppression circuit, and a level conversion circuit, which realizes interface lightning indirect effect protection, power supply compatibility protection, common-mode noise suppression, and RS485 asynchronous serial port level conversion functions. The voltage regulator board uses a linear voltage regulator, which is installed close to the surface of the chassis and coated with thermal grease. The voltage regulator board uses a three-terminal voltage regulator to convert the input +28VDC to +5VDC to provide power to the control board and the matching detection network. The control board is based on an MCU circuit and, according to the frequency, tuning commands, and status query commands issued by the system, realizes functions such as communication with the system, control of the vector impedance detection circuit, control of the tuning power generation circuit, control of the matching network, and storage of tuning parameters.

6. The antenna tuner based on an internal vibration reduction structure according to claim 5, characterized in that, The detection board uses a directional coupler to sample the tuned radio frequency signal in the frequency range of 2MHz to 45MHz, and sends the voltage and current sampling signals to the control unit for impedance measurement; the directional coupler has 45 turns, an inductance of 80μH to 180μH at 2MHz, a standing wave ratio S11 ≤ 1.2, and a coupling degree S21 = 33dB ± 1dB; The relay group uses high-voltage ceramic vacuum relays with a peak operating voltage of 10kVDC and an effective current carrying capacity of 25ADC. The inductor group is made of air-core coil winding; The capacitor bank on the capacitor plate is selected as a radio frequency high-Q capacitor.

7. The antenna tuner based on an internal vibration reduction structure according to claim 5, characterized in that, The interface board, control board, and detection board are all installed in a fully shielded independent metal cavity to ensure electromagnetic compatibility and tuning performance. The interface board and control board are blind-mating connected to the network base plate via printed circuit connectors, and all cross-linking signals are filtered. The connection between the control board and the network base plate is designed with a metal shielding channel according to the connector size. At the same time, a window is made on the top layer of the corresponding contact surface on the network base plate to provide ground solder mask. After being fixed and tightened with screws, full shielding is achieved. The interface between the interface board and the network base plate uses a micro rectangular filter electrical connector. Shielding and filtering are achieved by increasing the contact area between the connector's metal flange shell and the shielding cover and by using conductive pads.

8. The antenna tuner based on an internal vibration reduction structure according to claim 5, characterized in that, The ultra-flexible shielding channel includes a wave-shielding sleeve, a shielding tail clip, a metal shielding tube, an external interface connector, and a clamp; The power lines and asynchronous serial bus between the interface board and the external interface are fully shielded 360° using an ultra-flexible shielding channel composed of a wave-shielding sleeve, a shielded tail clip, and a metal shielding tube. Meanwhile, the external interface uses a C-type circuit-type square flange filter connector, and capacitors of different capacities are combined according to the signal characteristics to achieve filtering, shielding, and grounding, preventing common-mode interference and stray noise from the power lines and asynchronous serial bus from entering the RF path.

9. The antenna tuner based on an internal vibration reduction structure according to claim 8, characterized in that, The anti-surge sleeve is made of tin-plated copper foil wire; the external interface uses a threaded shielding tail clip with a maximum outer diameter of 20mm and an internal thread of M18×1-6H-6; the flexible cable interface of the interface board uses a metal shielding tube with a flange structure, with a flange diameter of 18mm and a thickness of 1.5mm; a positioning flange is set on the shielding tail clip and the metal shielding tube 7mm from the tail, with a flange diameter of 17.5mm and a thickness of 1mm; the clamp is a circular clamp with an outer diameter of 17.5mm, an inner diameter of 15.5mm, and a thickness of 5mm; the shielding tail clip, shielding tube, and clamp housing are all made of aluminum alloy with a 15μm electroless nickel plating on the surface.

10. The antenna tuner based on an internal vibration reduction structure according to claim 9, characterized in that, Before installation, prepare a surge protector of matching length based on the distance between the shielding tail clip of the external interface connector and the metal shielding tube of the interface board. During installation, first fix the external interface connector to the chassis housing with four M3 screws. Then screw the shielding tail clip into the tail end of the external interface connector. Next, put the surge protector onto the flexible cable and wrap it 7mm around the shielding tail clip. Then press the clamp into the shielding tail clip. Finally, weld the shielding tail clip, clamp, and surge protector together to achieve a 360° ring connection and reliably ground the cavity. On the other end, use two M2.5 screws to press the flange of the metal shielding tube with flange structure onto the interface board. Then, put the surge protector onto the metal shielding tube and wrap it 7mm around the metal shielding tube. Then press the clamp into the metal shielding tube. Finally, weld the metal shielding tube, clamp, and surge protector together to achieve a 360° ring connection and reliably ground the cavity. Ultimately, this achieves full shielding of all interface signals.

Images