Directional coupler

Abstract

The application discloses a directional coupler, relates to the technical field of satellite navigation antennas, and comprises a plurality of coupling channels, a power distribution network, a shielding structure and an edge intelligent processing unit. The plurality of coupling channels are separated by metal isolation structures. The power distribution network is composed of a plurality of power distributors. The shielding structure covers the plurality of coupling channels and the power distribution network. A temperature-sensitive capacitor is arranged outside the plurality of coupling channels. A distributed heat dissipation substrate is arranged outside the power distribution network. An EBG shielding cover is arranged outside the shielding structure. A hierarchical electromagnetic suppression system is formed based on the EBG shielding cover and the distributed heat dissipation substrate. A dynamic linkage is formed based on the temperature-sensitive capacitor and the plurality of coupling channels, the capacitor parameters are adjusted in real time to compensate for temperature drift, and the phase consistency is optimized. The edge intelligent processing unit performs physical relationship modeling according to data obtained by a multi-physical field sensing network integrated by the plurality of coupling channels, the power distribution network and the shielding structure.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of satellite navigation antennas, and particularly relates to a directional coupler. BACKGROUND

[0002] Directional couplers are widely used in wireless communication systems for signal distribution, power monitoring, antenna feed networks, etc. In the field of testing and measurement, directional couplers are used to extract signals from transmission paths for monitoring power levels or analyzing signals without affecting the performance of the entire system. In the military and aerospace fields, directional couplers are indispensable components in radar and satellite communication systems for signal routing and power control.

[0003] Traditional directional couplers adopt a stripline structure. The stripline high-coupling coupler is a three-layer structure with a dielectric layer in the middle and ground layers on both sides. The conductive strip in the middle dielectric layer transmits signals. The directional coupler of this structure has good directivity because the upper and lower layers are the same uniform medium. However, the amplitude and phase parameters of the stripline coupler cannot be adjusted because the transmission line is buried in the dielectric layer. When multiple coupler channels are connected to one channel, the amplitude and phase of each channel cannot be consistent. Moreover, compared with microstrip lines, the processing cost of stripline lines is higher. A microstrip directional coupler uses two or more closely spaced conductive paths on the same substrate to achieve coupling. Because the microstrip line is below the dielectric plate and above the air, the upper and lower media of the coupler are not uniform, causing differences in the odd and even mode phase velocities, which degrades the directivity of the microstrip directional coupler. To compensate for the above shortcomings of the microstrip directional coupler and meet the requirements of actual engineering tasks and reduce costs, a high-directivity coupler with a microstrip line structure is designed. This microstrip high-directivity coupler adopts a two-stage coupling structure. By utilizing the protrusions and recesses of the coupled microstrip lines, the microstrip high-directivity coupler effectively solves the problem of changing the odd and even mode phase velocities due to the non-uniformity of the upper and lower media, forming a high-directivity microstrip line coupler. SUMMARY

[0004] The present application provides a directional coupler, which solves the problem of unadjustable structure and poor consistency of multiple channels in the prior art, and achieves the technical effects of low cost, high directivity, and support for amplitude and phase adjustment of multiple channels.

[0005] A directional coupler, characterized in that it comprises:

[0006] A plurality of coupling channels, a power distribution network, a shielding structure, and an edge intelligent processing unit. The plurality of coupling channels are separated by a metal isolation structure. The power distribution network is composed of multiple power distributors. The shielding structure covers the plurality of coupling channels and the power distribution network.

[0007] A temperature-sensitive capacitor is arranged outside the multi-path coupling channel; a distributed heat dissipation substrate is arranged outside the power distribution network; an EBG shielding cover is arranged outside the shielding structure;

[0008] The EBG shielding cover and the distributed heat dissipation substrate form a hierarchical electromagnetic suppression system; the temperature-sensitive capacitor and the multi-path coupling channel form a dynamic linkage, and the capacitance parameter is adjusted in real time to compensate for temperature drift and optimize phase consistency.

[0009] The edge intelligent processing unit performs physical relationship modeling by integrating the data obtained by the multi-physical field sensing network arranged in the multi-path coupling channel, the power distribution network and the shielding structure.

[0010] Further, each channel in the multi-path coupling channel contains a microstrip high-directivity coupling unit, which is composed of an input port, an output port, a coupling port, an isolation port, a 50-ohm resistor 105 and a two-stage coupler.

[0011] Isolation resistors are used to connect each distributor in the power distribution network to combine the coupling signals of the multi-path coupling channel into one output.

[0012] The shielding structure is used to suppress external interference and inter-channel crosstalk.

[0013] Further, the temperature-sensitive capacitor is a temperature-sensitive capacitor connected outside the combining port, which automatically adjusts the output phase of the coupler through a feedback circuit to compensate for the phase deviation caused by temperature drift.

[0014] The combining port is the output port after signal combination.

[0015] The distributed heat dissipation substrate is a high-thermal-conductivity insulating gasket attached to the bottom of the PCB of the power distributor, and an aluminum heat dissipation substrate is externally connected to conduct the resistance heat out of the external heat sink through the gasket.

[0016] The EBG shielding cover is nested outside the coupler metal cavity, and the unit period corresponds to the suppression frequency band of 5.3-5.5GHz, which is used to suppress external electromagnetic interference and internal inter-channel radiation leakage.

[0017] Further, the hierarchical electromagnetic suppression system, wherein the period unit size of the EBG shielding cover and the multi-path coupling channel spacing satisfy the matching relationship The filling density of the wave-absorbing material is reduced to [30%, 50%] while maintaining the inter-channel mutual coupling not greater than -40dB.

[0018] Further, the temperature-sensitive capacitor and the multi-path coupling channel constitute a dynamic linkage, which means that the temperature sensor in the temperature-sensitive capacitor array collects real-time environmental temperature data and inputs the temperature parameters into the closed-loop feedback control system to dynamically adjust the varactor capacitance of each coupling channel to offset the dielectric constant deviation of the medium caused by temperature changes and maintain the phase consistency of the multi-path coupling channel.

[0019] Further, the two-stage coupler includes a first-stage coupling length branch 101 and a second-stage coupling length branch 104, and the input port and the output port of the two-stage coupler are connected in series with an adjustable capacitor and in parallel with an adjustable inductor; the impedance of the coupler port is changed by adjusting the values of the capacitor and the inductor to indirectly adjust the odd-even mode phase velocity and compensate for the phase difference caused by medium non-uniformity.

[0020] An externally mounted adjustable matching network is arranged to perform odd-even mode phase velocity adjustment and phase compensation on the transmission signals of the input port and the output port of the two-stage coupler of the coupling unit, the equivalent dielectric constant of the transmission line is changed by adjusting the element parameters of the series adjustable capacitor and the parallel adjustable inductor, and compensation data for the phase consistency of the multi-path coupling channel is obtained.

[0021] Further, the adjustable capacitor and the adjustable inductor further include: decoupling control of the adjustable capacitor and the adjustable inductor to establish an independent mapping relationship between the capacitor, the inductor, and the amplitude and phase, and the target capacitor and inductor are calculated in real time to drive the adjustable capacitor actuator to independently adjust each element.

[0022] Further, the externally mounted adjustable matching network further includes:

[0023] The capacitor and the inductor are packaged in a separate low-temperature co-fired ceramic module, connected to the coupler microstrip line through gold wire bonding, and the module bottom is integrated with a micro heat sink; the low-temperature co-fired ceramic module is embedded with copper pillars for heat conduction, and the heat dissipation efficiency is improved to 5W / cm²;

[0024] The low-temperature co-fired ceramic module is a high-performance electronic component based on a multi-layer ceramic technology.

[0025] Further, the multi-physical field sensor network integration includes: arranging sensors in the temperature field, vibration field, humidity field, and electromagnetic field to obtain data;

[0026] The physical relationship modeling includes: establishing the interaction relationship between the temperature field, the vibration field, the humidity field, and the electromagnetic field, and dynamically mapping the phase consistency of the multi-path coupling channel, the signal loss of the power distribution network, and the electromagnetic suppression efficiency of the EBG shield.

[0027] Further, the edge intelligent processing unit further includes:

[0028] The dynamic modeling analysis module is based on the physical relationship modeling, and calculates the phase compensation amount and shielding efficiency correction value of each coupling channel in real time; the phase compensation amount is used to adjust the equivalent dielectric constant offset of the transmission line; and the shielding efficiency correction value is used to dynamically adjust the EBG unit period and the filling density of the wave-absorbing material to compensate for the band gap frequency drift caused by vibration deformation.

[0029] The cross-field collaborative control module synchronously applies the compensation parameters output by the dynamic modeling analysis module to the amplitude adjuster of the multi-path coupling channel, the impedance matching node of the power distribution network and the electromagnetic suppression parameter of the shielding structure; and the electromagnetic suppression parameter is used to compensate for the signal attenuation caused by the dielectric loss.

[0030] The one or more technical solutions provided in the application have at least the following technical effects or advantages:

[0031] By using the directional coupler integrating the multi-path temperature-sensitive compensation coupling channel, the EBG hierarchical shielding structure and the multi-physical field intelligent collaborative control system, the multi-channel phase consistency, temperature stability and anti-interference capability are significantly improved through dynamic phase correction, hierarchical electromagnetic suppression and edge computing modeling, and the directional coupler is suitable for the field of high-precision satellite navigation. BRIEF DESCRIPTION OF DRAWINGS

[0032] Figure 1 A flowchart of the directional coupler in the embodiment of the application;

[0033] Figure 2 A PCB structure diagram of the microstrip high-directivity coupler of channel 1 and channel 2 in the embodiment of the application;

[0034] Figure 3 A PCB structure diagram of the microstrip high-directivity coupler of channel 3 and channel 4 in the embodiment of the application;

[0035] Figure 4 A PCB structure diagram of the microstrip high-directivity coupler of channel 5 and channel 6 in the embodiment of the application;

[0036] Figure 5 A PCB structure diagram of the microstrip high-directivity coupler of channel 7 and channel 8 in the embodiment of the application;

[0037] Figure 6 A structure diagram of the directional coupler in the embodiment of the application;

[0038] Figure 7 A return loss diagram of the power combiner at the port in the embodiment of the application;

[0039] Figure 8 A multi-channel coupling degree diagram in the embodiment of the application;

[0040] Figure 9A multi-channel isolation degree diagram in an embodiment of the present application;

[0041] Figure 10 A multi-channel phase consistency diagram in an embodiment of the present application;

[0042] Reference signs:

[0043] 101: first-stage coupling length stub; 102: first-stage coupling; 103: second-stage coupling; 104: second-stage coupling length stub; 105: 50-ohm resistor; 201: first power divider; 202: second power divider; 203: third power divider; 204: fourth power divider; 205: fifth power divider; 206: sixth power divider; 207: seventh power divider. DETAILED DESCRIPTION

[0044] For the purpose of facilitating the understanding of the present application, a more comprehensive description of the present application will be given below with reference to the relevant drawings; the drawings show a preferred embodiment of the present application, however, the present application can be realized in many different forms and is not limited to the embodiments described herein; on the contrary, the purpose of providing these embodiments is to make the disclosure of the present application more thorough and comprehensive.

[0045] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present application belongs; the terms used herein in the specification of the present application are only for the purpose of describing the specific embodiments and are not intended to limit the present application; the term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0046] Embodiment one: as Figure 2 、 3 , 4, 5, a directional coupler, comprising:

[0047] comprising a plurality of coupling channels, a power distribution network, a shielding structure and an edge intelligent processing unit; the plurality of coupling channels are separated by a metal isolation structure; the power distribution network is composed of multiple power dividers; the shielding structure covers the plurality of coupling channels and the power distribution network;

[0048] Each channel in the plurality of coupling channels contains a microstrip high-directivity coupling unit, the coupling unit is composed of an input port, an output port, a coupling port, an isolation port, a 50-ohm resistor 105 and a two-stage coupler;

[0049] Specifically, the multi-path coupling channel includes channels 1-8; the power divider is composed of a first power divider 201, a second power divider 202, a third power divider 203, a fourth power divider 204, a fifth power divider 205, a sixth power divider 206, and a seventh power divider 207; all use 50-ohm resistors as isolation resistors; the multi-path coupling channels are separated by a metal isolation structure, each channel contains a microstrip high-directivity coupling unit, which is composed of an input port (port 1), an output port (port 2), a coupling port (port 3), an isolation port (port 4), a 50-ohm resistor 105, a first-stage coupling 102, and a second-stage coupling 103; the directional coupler adopts a microstrip line structure.

[0050] When the input signal enters from port 1, more than 90% of the signal is output to port 2, and less than 10% of the signal is shunted to port 3 through electromagnetic coupling mechanism, and port 4 has no signal or very weak signal, and in an ideal case, it is completely isolated; one-way coupling of the signal is realized; the microstrip high-directivity coupling unit can realize adjustment of the amplitude of the high-directivity coupler by adjusting the lengths of the two-stage couplers.

[0051] Specifically, after the input signal enters from port 1, part of the energy is transferred to the auxiliary line through electromagnetic coupling of the main transmission line and the auxiliary transmission line (first-stage coupling 102), and the remaining signal of the main transmission line continues to be transmitted and part of the energy is again transferred to the auxiliary line through electromagnetic coupling (second-stage coupling 103), and the length of the transmission line between the two-stage couplings is half a wavelength (λ / 2) ), which ensures that the energies of the two couplings are opposite in phase at port 4, realizing destructive interference.

[0052] The distance between the two-stage couplings is half a wavelength, and the phase difference between the first-stage coupling 102 and the second-stage coupling 103 in the auxiliary line during the transmission of the signal from the first-stage coupling 102 to the second-stage coupling 103 is 180°, and when the energies of the two paths meet at port 4, the amplitudes are equal and the phases are opposite, resulting in complete destructive interference, and in an ideal case, no energy is output from port 4:

[0053] ,

[0054] wherein, is the total electric field of the isolation port, represents the superposition result of the two signals at this point, and if , then ;

[0055] is the absolute phase delay of the first-stage coupling 102 when transmitted to port 4; is in the form of a complex exponential, representing the phase rotation accumulated by the signal of the first-stage coupling 102 during transmission; The first stage coupling ensures a fixed phase difference for the second stage coupling 103, which ensures that the two signals are in phase opposition at port 4; by adjusting the coupling strength (C1, C2) ) and the distance, the isolation of port 4 is greater than 56dB.

[0056] When the two-stage coupling reaches port 3, due to the symmetry of the transmission path, the phases are the same, constructive interference is achieved, and the coupling signal strength is maximized:

[0057] ,

[0058] wherein, is the total electric field at port 3, which represents the synthesis of the two coupling signals at this point, and the amplitude and phase determine the output power of port 3; is the common phase delay of the two-stage coupling signals at port 3, which represents the absolute phase of the two paths; is the phase delay accumulated by the signal in the transmission path; is the electric field amplitude transmitted to port 3 through the first coupling; is the electric field amplitude transmitted to port 3 through the second coupling; if the coupling strengths of the two stages are equal (C1=C2) ), the energy of port 3 is 2 times that of single-stage coupling, and the coupling degree is improved by 3dB.

[0059] The power distribution network uses isolation resistors between each distributor to combine the coupling signals of multiple coupling channels into one output.

[0060] Specifically, the coupling ports of each channel are connected to one road using a one-to-two power divider (201, 202, 203, 204, 205, 206, 207), and the combined coupling port is connected using a radio frequency connector; the input port (port 1) of the coupler is connected using a contact radio frequency connector (port 1); the output port (port 2) of the coupler is connected to the antenna port; the coupling port (port 3) of the coupler is connected to the power divider; the isolation port (port 4) of the coupler is connected to a 50 ohm resistor 105.

[0061] The directional coupler is simulated by Ansys standard three-dimensional electromagnetic simulation tool, as shown in Figure 7 , the return loss at the combined port of the power divider (203) after the combination of the multiple coupling channels is less than -20dB in the entire frequency band, 5.3GHz-5.5GHz frequency band; as shown in Figure 8 , the coupling degree of channel 1-channel 8 coupling to the combined port of the power divider (204) is 25dB, and after passing through three one-to-four power dividers to the combined port, there is a 9dB attenuation, and the coupling port to the power divider after combination is 34.5dB±0.25dB.

[0062] Reserve the half-wavelength distance difference between two-stage coupling structure, so that the isolation of the isolation port is increased; as Figure 6 As shown in the figure, a certain length branch (101) is added between the two-stage couplers, and the phase difference of each channel can be adjusted by the distance between the two-stage couplers in each coupling channel, so that the phase consistency of each channel is maintained.

[0063] The shielding structure is used to suppress external interference and inter-channel crosstalk.

[0064] Specifically, to avoid the influence of external electromagnetic environment on the coupler, a metal shielding cover is added above the metal cavity, so that the multi-channel coupler is completely isolated from the outside world, as shown in Figure 7 As shown in the figure, the return loss of the combining coupler is below 25dB; as shown in Figure 8 As shown in the figure, the coupling degree of each coupling channel is 34.5dB±0.25dB, and the amplitude difference of each channel after combining through the power divider is within 0.3dB; as shown in Figure 9 As shown in the figure, the isolation of each coupling channel is more than 56dB, and the directivity is greater than 20dB; as shown in Figure 10 As shown in the figure, the phase difference of each channel after combining through the power divider is within 3°.

[0065] For example, without using a metal isolation structure, the multi-channel phase difference is ±5°; after using the structure of embodiment one, the actual measured phase difference is ≤±3. The microstrip line structure reduces the processing cost by 62% compared to the traditional stripline, and the production cost of a single piece is reduced from 85 to 32.

[0066] The technical solutions in the above embodiments of the application have at least the following technical effects or advantages:

[0067] The application designs a multi-channel microstrip line structure directional coupler, each channel of the directional coupler adjusts the phase through a two-stage coupling structure, and adjusts the amplitude and phase inconsistency after processing; the microstrip line structure is used, so that the production cost is reduced; the isolation walls are used to isolate each channel, so that the signal crosstalk between each channel is effectively prevented; in the frequency band of 5.3GHz-5.5GHz, the directivity of each channel is more than 20dB; a low-cost, high-directivity, multi-channel amplitude and phase adjustment supporting microstrip line structure directional coupler is provided, which solves the problem of poor consistency of traditional structure and non-adjustable multi-channel.

[0068] Embodiment two: in embodiment one, by designing a low-cost, high-directional, supporting multi-channel amplitude and phase adjustment of microstrip line structure directional coupler, solve the problem of traditional structure unadjustable, poor consistency of multi-channel, but use metal partition wall and shielding cover, there may be leakage at high frequency, resulting in insufficient isolation; the resistance of the power divider may have overheating risk, affecting the reliability; this embodiment further improves embodiment one.

[0069] The temperature-sensitive capacitor is arranged outside the multi-coupling channel; a distributed heat dissipation substrate is arranged outside the power distribution network; and an EBG shielding cover is arranged outside the shielding structure.

[0070] The temperature-sensitive capacitor is a temperature-sensitive capacitor connected outside the combining port, which automatically adjusts the phase of the coupler output through a feedback circuit to compensate for the phase deviation caused by temperature drift; and the combining port is an output port after signal combination.

[0071] Specifically, the capacitor array is externally connected to the combining port through an SMA (radio frequency coaxial connector) joint, and the FPGA (a semiconductor device that can reconfigure hardware logic through programming) is embedded in the side wall of the cavity and independently powered; the temperature-sensitive element adopts an NTC (negative temperature coefficient) thermistor (precision ±0.5℃) and a MEMS (micro-electro-mechanical system) variable capacitance diode (capacitance 0.5-2pF) array; temperature data is collected in real time through the FPGA to adjust the capacitance value and compensate for the phase temperature drift, and the compensation model is:

[0072] ,

[0073] Among them, is the amount of capacitance change that needs to be compensated; is the initial capacitance value; is the temperature coefficient, =50ppm / ℃; T is the current temperature, is the reference temperature, usually 25℃; the phase consistency is optimized from ±3° to ±1.8°, and the temperature drift coefficient is reduced by 40%.

[0074] The distributed heat dissipation substrate is a high-thermal-conductivity insulating pad attached to the bottom of the power divider PCB, and an aluminum heat dissipation substrate is externally connected, so that the resistance heat is conducted to the external heat sink through the pad;

[0075] A high-thermal-conductivity insulating pad is attached to the back of the power divider PCB (printed circuit board), and an aluminum heat dissipation substrate is externally connected and fixed to the cavity bottom plate by bolts; during heat dissipation, the heat is sequentially transmitted to the high-thermal-conductivity insulating pad and the heat dissipation substrate and finally conducted to the external heat sink; by externally connecting the heat dissipation substrate, the power capacity is increased from 5W to 15W, and the resistance area temperature rise ΔT≤30℃.

[0076] The EBG shield is a detachable EBG structure shield nested outside the metal cavity, the unit period of which corresponds to the suppression frequency band of 5.3-5.5 GHz, and is used for suppressing electromagnetic interference outside the cavity and radiation leakage between internal channels.

[0077] A low-cost FR4 (a commonly used substrate type in electronic circuit boards) board (thickness 1.6 mm) is used, and a mushroom-shaped EBG unit is etched on the surface as an EBG (electromagnetic bandgap) shield, which is connected with the original metal cavity through a buckle-type conductive spring to form a double-layer shielding structure. The EBG unit generates a bandgap effect (stopband attenuation ≥20 dB) at the target frequency band to suppress the propagation of surface waves. The back of the FR4 substrate is coated with a flexible ferrite wave-absorbing layer (thickness 0.2 mm) to absorb near-field radiation. The isolation degree is improved from 56 dB to 62 dB, and the insertion loss fluctuation is ≤0.1 dB.

[0078] A hierarchical electromagnetic suppression system is formed based on the EBG shield and the distributed heat dissipation substrate. A dynamic linkage is formed based on the temperature-sensitive capacitor and the multiple coupling channels to adjust the capacitor parameters in real time to compensate for temperature drift and optimize the phase consistency.

[0079] The hierarchical electromagnetic suppression system, wherein the period unit size of the EBG shield and the spacing between the multiple coupling channels satisfy the matching relationship , so that the filling density of the wave-absorbing material is reduced to [30%, 50%] while the mutual coupling between channels is still not greater than -40 dB.

[0080] Specifically, the period unit size of the EBG shield and the spacing between the multiple coupling channels need to satisfy:

[0081] ,

[0082] wherein d is the period unit size, is the center wavelength of the working frequency band, such as the wavelength = 56.6 mm corresponding to 5.4 GHz, is the relative dielectric constant of the substrate material, such as = 4.3 for FR4; so as to ensure that the bandgap of the EBG structure is accurately matched with the crosstalk frequency band between channels, and the periodic structure absorbs or reflects the interference electromagnetic waves through the resonance effect.

[0083] The wave-absorbing material supplements the high-frequency stray interference not covered by the EBG. If the channel spacing s = 12 mm and the substrate = 4.3, then the EBG period unit size is:

[0084] ,

[0085] At this time, the filling density of the wave-absorbing material can be reduced to 35%, and the mutual coupling is still ≤-40 dB.

[0086] Using EBG shield and 30% wave-absorbing material can suppress mutual coupling to -42dB, reduce the weight of wave-absorbing material from 120g to 50g, and achieve lightweight, high suppression and low cost hierarchical electromagnetic shielding.

[0087] The temperature-sensitive capacitor and the multiple coupling channels constitute a dynamic linkage, which means that the temperature sensor in the temperature-sensitive capacitor array collects real-time environmental temperature data and inputs the temperature parameter into a closed-loop feedback control system to dynamically adjust the capacitance diode capacitance of each coupling channel to offset the dielectric constant deviation of the medium caused by temperature change and maintain the phase consistency of the multiple coupling channels.

[0088] Specifically, the temperature-sensitive capacitor directly acts as a sensor to read the capacitance value or temperature value in real time through an analog-to-digital converter with a sampling frequency ≥10Hz. According to the collected capacitance value or temperature value, a temperature-phase mapping model is established:

[0089] ,

[0090] wherein, is the phase change amount, is the temperature change amount, k is the phase offset amount caused by each degree Celsius temperature change, which is measured as +0.2℃; compensation requires reverse adjustment of the coupling length to offset the temperature drift, , is the phase change compensation amount.

[0091] The relationship between the phase change compensation amount and the electrical length is:

[0092] ,

[0093] wherein, is the equivalent electrical length change amount, c is the speed of light in vacuum, and f is the working frequency; when =0.1mm / pF· C, f=28Ghz, C is the capacitance adjustment amount, and substitution can obtain the corresponding phase compensation amount .

[0094] Fast continuous adjustment (response time: <100ns) uses varactor diodes; high-precision discrete adjustment (adjustment step: 0.1pF) uses MOS (a type of semiconductor material) switch to switch capacitor combination; PID controller (feedback control algorithm) is adopted to adjust the capacitance value according to the real-time phase error to ensure that the steady-state error is <0.1°.

[0095] For example, the temperature drift inhibition effect of the compensation model verification is that the phase shift is optimized from ±3° to ±1.8° in the temperature variation test of-40°C to +85°C, the temperature drift coefficient is reduced by 43%, the power divider resistance area temperature rise is reduced from 52°C to 28°C when working continuously for 15W, the EBG shield makes the isolation of the 5.4GHz frequency point increase from 56dB to 62dB in the vector network analyzer test, and the insertion loss fluctuation is less than or equal to 0.1dB.

[0096] The technical solutions in the embodiments of the application have at least the following technical effects or advantages:

[0097] The application adopts the external EBG shield to simplify the production complexity and reduce the precision machining cost; the wave-absorbing material filling density is low, and the material cost is further compressed; the heat dissipation substrate does not need an active temperature control system, and the hardware cost is reduced; the hierarchical electromagnetic suppression system effectively suppresses the mutual coupling between channels and external interference, and maintains high directivity; the temperature-sensitive compensation network reduces the influence of temperature drift on phase consistency, and indirectly improves the directivity.

[0098] Embodiment three: Embodiment two realizes performance improvement in a static environment by external hardware, but cannot cope with dynamic changes; this embodiment further improves embodiment two.

[0099] The two-stage coupler includes a first-stage coupling length branch 101 and a second-stage coupling length branch 104, and the input port and the output port of the two-stage coupler are both in series with an adjustable capacitor and in parallel with an adjustable inductor; the values of the capacitor and the inductor are adjusted to change the port impedance of the coupler, indirectly adjust the odd / even mode phase velocity, and compensate for the phase difference caused by the non-uniformity of the medium; an external adjustable matching network is arranged to adjust the odd / even mode phase velocity of the transmission signal of the input port and the output port of the two-stage coupler of the coupling unit, change the equivalent dielectric constant of the transmission line by adjusting the element parameters of the series adjustable capacitor and the parallel adjustable inductor, and obtain compensation data for the phase consistency of multiple coupling channels.

[0100] Specifically, the input / output end of the original two-stage coupler is in series with an adjustable capacitor and in parallel with an adjustable inductor; the values of the capacitor / inductor are adjusted to change the port impedance of the coupler, indirectly adjust the odd / even mode phase velocity, and compensate for the phase difference caused by the non-uniformity of the medium, and the formula is:

[0101] ,

[0102] wherein, is the equivalent dielectric constant, which is affected by the adjustment of the series capacitor (C) and the parallel inductor (L), is the change amount of the electrical length of the coupler.

[0103] The adjustable capacitor and the adjustable inductor further comprise: decoupling control based on the adjustable capacitor and the adjustable inductor, establishing an independent mapping relationship of the capacitor, the inductor, and the amplitude and the phase, and driving the adjustable capacitor actuator to independently adjust each element by real-time solving of the target capacitor and the inductor.

[0104] Specifically, in the directional coupler, the capacitor and By adjusting the impedance matching of the input / output end, the signal coupling efficiency is affected. For example, increasing and will reduce the series impedance, allowing more signal energy to be coupled from port 1 to port 3, thereby improving While and Parallel inductive resistance will shunt high-frequency signal energy and suppress amplitude; an amplitude adjustment model is established:

[0105] ,

[0106] Among them, is the amplitude of the transmission coefficient from port 3 to port 1 of the coupler, reflecting the energy transmission efficiency from the input to the coupling port; and are adjustable capacitors in series at the input and output ports. Increasing the capacitance value will enhance the electric field coupling, thereby improving the amplitude of ; and are adjustable inductors in parallel on both sides of the transmission line. Increasing the inductance will increase the inductive reactance, suppress high-frequency signal transmission, and reduce ; and are coefficients determined by the characteristic impedance of the transmission line and the working frequency, The value range is [ , ], The value range is [01, 40].

[0107] The phase delay is related to the ratio of the inductive reactance and the capacitive reactance. By adjusting the difference between L and C, the phase velocity of the odd and even modes can be controlled, and then is adjusted; if and Inductive dominance leads to negative; if and Capacitive dominance leads to positive; a phase adjustment model is established:

[0108] ,

[0109] Among them, The difference in inductance introduces inductive phase shift for the inductance located in the two arms of the coupler. The difference in capacitance introduces capacitive phase shift for the capacitance connected in parallel to the coupling arms. The ratio of the inductance difference to the capacitance difference is converted into a phase angle to reflect the quadrature modulation relationship.

[0110] The capacitance and inductance are packaged in independent low-temperature co-fired ceramic modules, connected to the coupler microstrip line through gold wire bonding, and the module bottom is integrated with a micro heat sink; the low-temperature co-fired ceramic module is embedded with a copper column for heat conduction, and the heat dissipation efficiency is improved to 5W / cm²; the low-temperature co-fired ceramic module is a high-performance electronic component based on a multilayer ceramic process.

[0111] Specifically, the low-temperature co-fired ceramic module independently packages the adjustable capacitance / inductance in a multilayer ceramic structure, and realizes electrical isolation through internal copper column embedding and vertical interconnection. This design can reduce parasitic capacitance / inductance, such as less than 0.05pF / 0.1nH, allowing the capacitance and inductance to be adjusted independently, avoiding electromagnetic coupling between elements in traditional PCB layout; the module bottom is integrated with a micro heat sink and internal copper column heat conduction structure, ensuring that the decoupling control algorithm can stabilize the junction temperature of the adjustable capacitance actuator below 85°C when frequently adjusting elements, avoiding parameter drift caused by thermal runaway; compared with traditional solder joint connection, gold wire bonding connection has a 30% reduction in path impedance and a 0.3ps reduction in signal transmission delay.

[0112] For example, through vector network analyzer sweep data, the adjustable capacitance and inductance realize amplitude adjustment ±2dB and phase compensation ±15°; a high-speed oscilloscope captures the dynamic compensation response time <100ns, and real-time correction of 0.5° phase jitter caused by vibration.

[0113] The technical solutions in the above embodiments of the application have at least the following technical effects or advantages:

[0114] The external adjustable matching network realizes parameter adjustment through adjustable capacitance / inductance, reduces the cost of customized design; the decoupling control algorithm reduces the cost of manual debugging, reduces the production complexity through automation optimization, eliminates the mutual coupling effect in amplitude / phase adjustment in real time, and ensures high directivity; the adjustable capacitance / inductance array supports dynamic adjustment of the amplitude and phase of each channel, and realizes multi-channel independent control in combination with the algorithm.

[0115] Embodiment four: Embodiment three only considers a single factor, such as temperature, but in actual application, changes in multiple physical fields will simultaneously affect system performance. For example, temperature changes will affect the dielectric constant, vibration will cause mechanical deformation, and humidity may affect loss; this embodiment further improves embodiment three.

[0116] The multi-physical field sensor network integration includes arranging sensors in temperature field, vibration field, humidity field and electromagnetic field to acquire data;

[0117] Specifically, the temperature field uses a micro thin film platinum resistor to be attached to the surface of the dielectric plate; the vibration field uses a MEMS three-axis accelerometer; the humidity field uses a capacitive humidity sensor; and the electromagnetic field uses a micro directional coupler. The temperature sensor is distributedly arranged at the coupling line, resistor and power divider. The accelerometer is installed at the four corners and center of the cavity to capture six-degree-of-freedom vibration modes.

[0118] The physical relationship modeling includes establishing the interaction relationship among the temperature field, vibration field, humidity field and electromagnetic field, and dynamically mapping the phase consistency of the multi-path coupling channel, the signal loss of the power distribution network and the electromagnetic suppression efficiency of the EBG shield.

[0119] The edge intelligent processing unit performs physical relationship modeling by integrating the data acquired by the multi-physical field sensor network arranged in the multi-path coupling channel, power distribution network and shielding structure.

[0120] Specifically, the sensor network is used to collect the physical field data in real time, and a cross-field domain collaborative model is established, which is dynamically mapped to the performance parameters.

[0121] ,

[0122] wherein, is the total phase shift, is the phase shift caused by temperature change, is the phase shift caused by mechanical deformation caused by vibration, is the phase shift caused by the change of dielectric constant caused by humidity change, which can be adjusted in real time by temperature-sensitive capacitor and adjustable inductance to offset the phase shift:

[0123] ,

[0124] wherein, is the compensation capacitor; is the capacitor-phase adjustment coefficient, such as By adjusting the compensation capacitor , the equivalent electrical length of the transmission line is changed, so as to offset the total phase shift.

[0125] The power distribution network loss is jointly affected by temperature and humidity, and the heat dissipation substrate heat conduction efficiency and impedance matching network dynamic optimization:

[0126] , ​

[0127] wherein, is the heat dissipation efficiency, is the reference heat dissipation efficiency, is the temperature correction coefficient, the value range is [0.001, 0.01], is the temperature variation, i.e. the difference between the current temperature and the reference temperature, is the humidity correction coefficient, the value range is [-0.005, 0.001], H is the relative humidity of the current environment; dynamically adjust the heat dissipation efficiency according to the temperature and humidity changes to ensure that the resistance temperature rise in the power distribution network is controllable.

[0128] ,

[0129] wherein, is the matching impedance, is the reference matching impedance, is the loss correction coefficient, the value range is [0.05, 0.2], is the signal loss caused by temperature and humidity; by dynamically adjusting the impedance , compensate for the signal attenuation caused by the rise of temperature and humidity, maintain the transmission efficiency of the power distribution network.

[0130] By dynamically adjusting the density of the wave-absorbing material or the EBG unit period, the electromagnetic suppression efficiency is maintained, and the formula is obtained:

[0131] ,

[0132] wherein, p is the filling density of the wave-absorbing material, is the initial filling density of the wave-absorbing material, is the band gap frequency offset, is the band gap center frequency; when the vibration causes the band gap frequency of the EBG shielding cover to shift, the electromagnetic suppression performance is compensated by adjusting the filling density p of the wave-absorbing material.

[0133] The edge intelligent processing unit further comprises:

[0134] A dynamic modeling analysis module, based on the physical relationship modeling, real-time calculates the phase compensation amount and shielding efficiency correction value of each coupling channel; based on the phase compensation amount, adjusts the equivalent dielectric constant offset of the transmission line; based on the shielding efficiency correction value, dynamically adjusts the EBG unit period and the filling density of the wave-absorbing material to compensate for the band gap frequency drift caused by vibration deformation;

[0135] A cross-field domain collaborative control module synchronously applies the compensation parameters output by the dynamic modeling and analysis module to the amplitude adjuster of the multi-path coupling channel, the impedance matching node of the power distribution network, and the electromagnetic suppression parameter of the shielding structure; and compensates for signal attenuation caused by medium loss based on the electromagnetic suppression parameter. Specifically, a multi-physical field data interface module integrates multi-source environmental data of temperature, vibration, humidity, and electromagnetic field sensors to construct a real-time monitoring network;

[0136] A dynamic modeling and analysis module maps environmental changes to phase compensation parameters and electromagnetic shielding efficiency correction values, such as temperature drift phase deviation and vibration-induced deformation compensation, based on physical relationship modeling.

[0137] A cross-field domain collaborative control module links and controls the amplitude adjuster of the coupling channel, the impedance matching node of the power distribution network, and the EBG shielding parameter, to realize multi-system adaptive collaborative optimization under environmental disturbance.

[0138] For example, a laser interferometer measures deformation compensation, and under the condition of 5g / 100Hz vibration, the phase fluctuation is suppressed from ±2° to ±0.5°; a vector network analyzer tests, and when the relative humidity is 90%, the power distribution loss increases from 1.2dB to 0.5dB; a power analyzer monitors for 72 hours, and the edge intelligent unit reduces the system power consumption by 38%, from 8.5W to 5.3W.

[0139] In the scenario of actively enabling high-power applications, an overload mode is added to allow the temperature to break through the regular value within a certain time; when the directional coupler is used in a transient high-power scenario, the edge intelligent processing unit activates a three-level overload control strategy to realize first-level heat stress deformation prevention, second-level local ablation prevention, and third-level medium breakdown prevention, forming a complete failure protection chain:

[0140] The first-level strategy targets the heat shock buffering stage (0-30 seconds), switches the heat-conducting gasket of the distributed heat dissipation substrate to the phase change material working mode, and the instantaneous heat absorption capacity is increased to 8W / cm²; the EBG shielding cover starts the piezoelectric actuator to reduce the unit cycle by 12% to match the frequency offset; the temperature-sensitive capacitor is switched to the negative temperature coefficient mode, the compensation rate is increased to 200ppm / ℃, and the instantaneous heat shock buffering and frequency stability maintenance are realized;

[0141] The second-level strategy targets the power redistribution stage (30-120 seconds), and through the MOSFET (a kind of switching network used for dynamic power redistribution and redundant path switching) array of the adjustable matching network, 50% of the power is transferred to the redundant channel to reduce the single-point heat density, realize heat distribution balance and power bearing optimization;

[0142] The third-level strategy targets the emergency cooling stage (>120 seconds). Nitrogen microflows are injected into the copper column heat conduction channel of the low-temperature co-fired ceramic module to form forced convection cooling, generating a plasma sheath on the inner surface of the shielding cavity to achieve emergency heat dissipation and arc protection.

[0143] The technical solutions in the above embodiments of the present application have at least the following technical effects or advantages:

[0144] This application uses a multi-physics field sensing network to integrate temperature / pressure / electromagnetic sensors and a low-power edge computing unit to reduce data processing costs; physical relationship modeling corrects the impact of environmental changes on directionality in real time to maintain high directionality; and the adaptive adjustment mechanism suppresses dynamic interference through dynamic shielding and phase compensation.

[0145] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Various modifications and variations are readily apparent to those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A directional coupler, characterized by, The application relates to a multi-channel coupling channel, a power distribution network, a shielding structure and an edge intelligent processing unit. The multi-channel coupling channels are separated by a metal isolation structure; the power distribution network is composed of multi-stage power distributors; and the shielding structure covers the multi-channel coupling channels and the power distribution network. A temperature-sensitive capacitor is externally connected to a multi-channel coupling channel; and a distributed heat dissipation substrate is arranged outside the power distribution network. An EBG shielding cover is arranged outside the shielding structure. A hierarchical electromagnetic suppression system is formed based on the EBG shielding cover and the distributed heat dissipation substrate; and a dynamic linkage is formed based on the temperature-sensitive capacitor and the multi-channel coupling channel, temperature sensor in the temperature-sensitive capacitor array collects environmental temperature data in real time, and temperature parameters are input into a closed-loop feedback control system to dynamically adjust the capacitance of the variable capacitance diode of each coupling channel, so as to offset the dielectric constant deviation of the medium caused by temperature change and maintain the phase consistency of the multi-channel coupling channel. The edge intelligent processing unit performs physical relationship modeling according to the data obtained by the multi-channel coupling channel, the power distribution network and the shielding structure; the multi-physical field sensing network arranges sensors in a temperature field, a vibration field, a humidity field and an electromagnetic field to obtain data; and the physical relationship modeling includes establishing the interaction relationship among the temperature field, the vibration field, the humidity field and the electromagnetic field, and dynamically mapping the phase consistency of the multi-channel coupling channel, the signal loss of the power distribution network and the electromagnetic suppression efficiency of the EBG shielding cover.

2. A directional coupler as claimed in claim 1, characterized in that Each channel in the multi-channel coupling channel comprises a microstrip high-directivity coupling unit, which is composed of an input port, an output port, a coupling port, an isolation port, a 50-ohm resistor (105) and a two-stage coupler. Isolation resistors are used to connect the distributors in the power distribution network, which are used to combine the coupling signals of the multi-channel coupling channels into one output. The shielding structure is used to suppress external interference and channel crosstalk.

3. A directional coupler as recited in claim 1, wherein, The temperature-sensitive capacitor is externally connected to the combining port, and the output phase of the coupler is automatically adjusted through a feedback circuit to compensate for the phase deviation caused by temperature drift. The combining port is an output port after signal combination. The distributed heat dissipation substrate is a high-thermal-conductivity insulating gasket attached to the bottom of the PCB of the power distributor, and an aluminum heat dissipation substrate is externally connected to the gasket to conduct the resistance heat out of the gasket to an external heat sink. The EBG shielding cover is nested outside the metal cavity of the coupler, and the unit period corresponds to the suppression frequency band of 5.3-5.5 GHz, which is used to suppress the electromagnetic interference outside the cavity and the radiation leakage between the internal channels.

4. A directional coupler as recited in claim 1, wherein, The hierarchical electromagnetic suppression system, wherein the period unit size of the EBG shield cover and the multi-path coupling channel spacing satisfy The matching relationship, so that the filling density of the wave-absorbing material is reduced to [30%, 50%] while maintaining the inter-channel mutual coupling not greater than -40dB.

5. A directional coupler as recited in claim 2, wherein, The two-stage coupler comprises a first-stage coupling length branch (101) and a second-stage coupling length branch (104), and the input port and the output port of the two-stage coupler are connected in series with adjustable capacitors and in parallel with adjustable inductors; the values of the capacitors and the inductors are adjusted to change the port impedance of the coupler and indirectly adjust the odd-even mode phase velocity to compensate for the phase difference caused by the medium inhomogeneity. An external adjustable matching network is arranged to adjust and compensate the phase of the transmission signal of the input port and the output port of the two-stage coupler of the coupling unit by adjusting the element parameters of the series adjustable capacitor and the parallel adjustable inductor to change the equivalent dielectric constant of the transmission line and obtain compensation data of the phase consistency of the multiple coupling channels.

6. A directional coupler as claimed in claim 5, characterised in that, The adjustable capacitor and the adjustable inductor further comprise: decoupling control of the adjustable capacitor and the adjustable inductor, establishment of an independent mapping relationship of the capacitor, the inductor, the amplitude and the phase, real-time calculation of the target capacitor and the inductor, and independent adjustment of each element by driving the adjustable capacitor actuator.

7. A directional coupler as recited in claim 5, wherein, The external adjustable matching network further comprises: The capacitor and the inductor are packaged in an independent low-temperature co-fired ceramic module, connected with the microstrip line of the coupler through gold wire bonding, and integrated with a micro heat sink at the bottom of the module; the low-temperature co-fired ceramic module is embedded with a copper column for heat conduction, and the heat dissipation efficiency is improved to 5W / cm²; The low-temperature co-fired ceramic module is a high-performance electronic component based on a multilayer ceramic technology.

8. A directional coupler as recited in claim 1, wherein, The edge intelligent processing unit further comprises: A dynamic modeling analysis module, based on the physical relationship modeling, real-time calculation of the phase compensation amount and the shielding efficiency correction value of each coupling channel; adjustment of the equivalent dielectric constant offset of the transmission line based on the phase compensation amount; dynamic adjustment of the EBG unit period and the wave-absorbing material filling density based on the shielding efficiency correction value to compensate for the bandgap frequency drift caused by vibration deformation; A cross-field domain cooperative control module, the compensation parameters output by the dynamic modeling analysis module are synchronously applied to the amplitude adjuster of the multiple coupling channels, the impedance matching node of the power distribution network and the electromagnetic suppression parameters of the shielding structure; compensation of the signal attenuation caused by the dielectric loss based on the electromagnetic suppression parameters.

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