Adjustable radio frequency adapter of reconfigurable circuit

Abstract

The invention discloses an adjustable radio frequency adapter of a reconfigurable circuit, and relates to the technical field of radio frequency adapters, key function modules are integrated in a shielding cavity formed by an outer conductor, and the key function modules comprise an adjustable circuit module connected in series in a radio frequency path of an inner conductor, a detection module of the inner conductor and a control unit; the intelligent control method realizes dynamic impedance matching through closed-loop control: firstly, the control unit identifies the current resonant frequency of the antenna based on the forward and reflection power sampled by the detection module, and adjusts the parameters of the adjustable circuit module to align to the target working frequency; on a fixed target frequency, an embedded gradient descent and alternate optimization algorithm is operated, and an optimal parameter combination of an adjustable circuit module is accurately searched, so that a voltage standing wave ratio is minimized, and impedance conjugate matching is realized; the problem that a traditional adapter is fixed in function and cannot be dynamically adapted is solved, full automation, intelligence and high precision of radio frequency link tuning are achieved, and communication quality and system reliability are remarkably improved.

Description

Technical Field

[0001] This invention relates to the field of radio frequency adapter technology, and more specifically, to an adjustable radio frequency adapter with reconfigurable circuitry. Background Technology

[0002] With the large-scale commercialization of fifth-generation mobile communication technology and the launch of research into future sixth-generation communication technology, as well as the rapid development of industries such as the Internet of Things and aerospace, wireless communication systems are facing severe challenges: increasingly scarce spectrum resources, exponential growth in data transmission rates, and increasingly miniaturized and highly integrated device forms. Against this backdrop, the performance of the radio frequency front-end and interconnect components, as the nerve endings of the wireless system, directly determines the efficiency, reliability, and sophistication of the entire system.

[0003] RF adapters, as key passive components in RF circuits that enable signal transition, interface conversion, and power transmission, are widely used between antennas and RF front-end modules, between RF cables of different standards, and in test and measurement systems. Their traditional role is that of a passive conduit, with the core function of ensuring low-loss, low-reflection transmission of RF signals at both mechanical and electrical levels. However, the design and function of existing RF coaxial adapters have lagged significantly behind the needs of modern communication systems, and mainly suffer from the following inherent defects and limitations: (1) Single and rigid functions, unable to adapt to the development trend of reconfigurable RF architecture: After the design of traditional RF adapters is finalized, their electrical performance and physical structure are fixed, which means that they can only perform a single, pre-set connection task, becoming a bottleneck that limits the system's flexibility and spectrum utilization; (2) Performance is easily affected by the environment and lacks adaptive compensation capability: In practical applications, the performance of the RF front end is not constant. It will cause the circuit parameters to deviate from the design value due to changes in the external environment or internal environment, which seriously affects the communication quality and connection reliability; (3) Low system integration, hindering the miniaturization process of equipment: In order to realize the function of processing RF signals, multiple discrete functional devices must be connected in series in the RF link, which occupies valuable printed circuit board area and introduces additional connection loss and potential failure points. Meanwhile, complex wiring also increases the risk of electromagnetic interference; (4) High debugging and maintenance costs: During the system production or debugging phase, if the RF channel performance fails to meet the standards due to processing errors, it is usually necessary to redesign and replace the entire adapter or related functional modules, which is cumbersome and costly. During the maintenance phase, it is also impossible to remotely optimize and adjust the RF performance of the equipment deployed on site. Summary of the Invention

[0004] To address the above problems, the present invention provides an adjustable radio frequency adapter with a reconfigurable circuit.

[0005] This invention provides an adjustable radio frequency adapter with reconfigurable circuitry, comprising: The interface mechanism, located at both ends of the adjustable RF adapter, is used to achieve mechanical and electrical connection with external RF ports; The inner conductor, serving as the radio frequency signal transmission channel, is located at the axis of the shielded cavity formed by the outer conductor; The outer conductor forms a shielding cavity, which is used to provide electromagnetic shielding and form a loop path for radio frequency signals; The shielded cavity contains a fixed matching circuit for tuning the antenna's impedance, frequency, and bandwidth. As an optional embodiment, the fixed matching circuit (10) is a Π-type lumped parameter matching network, including a signal input port Port1, a first inductor L1, a second inductor L2, a first capacitor C1, a second capacitor C2, and a signal output port Port2; the first inductor L1 and the second inductor L2 are connected in series between the signal input port Port1 and the signal output port Port2 to form the backbone transmission path of the radio frequency signal; wherein one end of the first inductor L1 near the signal input port Port1 is connected to one end of the first capacitor C1, and the other end of the first capacitor C1 is grounded; the other end of the first inductor L1 is connected in parallel with one end of the second inductor L2 and then connected to one end of the second capacitor C2, the other end of the second capacitor C2 is grounded, and the other end of the inductor L2 is connected to the signal output port Port2.

[0006] As an optional embodiment, it also includes: A reconfigurable control signal transmission path is used to receive external commands and transmit them to the adjustable circuit module; An adjustable circuit module, integrated within a shielded cavity and connected in series or parallel in the radio frequency signal transmission path of the inner conductor, is used to receive external signals and adjust radio frequency parameters. The detection module, integrated within the shielded cavity, is used to detect the parameters of the radio frequency signal in real time. The control unit, integrated within the shielded cavity, is used to receive and process signals from the detection module and run the built-in intelligent control algorithm. Detect the signal transmission path and connect the detection module to the control unit; An adjustable control signal transmission path connects the control unit and the adjustable circuit module; The control unit is configured to dynamically adjust the parameters of the adjustable circuit module based on the signal fed back from the detection module through closed-loop control logic, so that the connected load achieves impedance matching at the target operating frequency.

[0007] As an optional embodiment, the adjustable circuit module is one or more of a varactor diode, PIN diode, RF MEMS switch, or adjustable capacitor / inductor integrated circuit.

[0008] As an optional embodiment, the detection module includes a directional coupler and a pair of detector chips respectively connected to the forward coupling port and the reverse coupling port of the directional coupler; the coupling arm of the directional coupler is arranged adjacent to the inner conductor in a capacitive or inductive coupling manner.

[0009] As an optional embodiment, the control unit performs the following intelligent control process: S1: System initialization, setting the adjustable circuit module to the preset initial state; S2: Frequency tuning stage: The control unit determines the current resonant frequency of the load by analyzing the voltage standing wave ratio-frequency curve obtained by frequency sweep measurement; if the difference between the current resonant frequency and the target operating frequency exceeds the frequency tolerance Δf, the frequency tuning process is triggered, and the parameters of the adjustable circuit module are adjusted to make the current resonant frequency approach the target operating frequency. S3: Impedance tuning stage: After frequency tuning is completed or the current resonant frequency meets the requirements, if the measured voltage standing wave ratio at the target operating frequency is greater than the maximum allowable standing wave ratio, the impedance tuning process is triggered. S4: Parameter Locking and Status Protection: When both frequency and voltage standing wave ratio requirements are met, the optimal parameters of the adjustable circuit module are locked.

[0010] As an optional embodiment, the frequency tuning process specifically includes: S2-1: Set the adjustable circuit module to an initial state covering a wide frequency range; S2-2: Send a series of step-by-step control commands to the adjustable circuit module to make its equivalent reactance change regularly, and after each control command takes effect, measure the corresponding forward power and reflected power through the detection module; S2-3: Calculate the voltage standing wave ratio (VSWR) for each capacitor setting point based on the measurement data, find the capacitor combination that minimizes the VSWR, and the frequency corresponding to this capacitor combination is the current resonant frequency; based on the preset capacitor setting-resonant frequency correspondence model, calculate and send the new capacitor value combination to the adjustable circuit module. S2-4: Verify whether the new current resonant frequency falls within the tolerance range of the target operating frequency ±Δf. If it does not, return to step S2-2 for iteration.

[0011] As an optional embodiment, the impedance tuning process specifically includes: S3-1, the RF source is set or maintained at the target operating frequency. The detection module accurately measures the forward power and reflected power at this single frequency point and calculates an accurate VSWR measured value, which is then fed back to the control unit. S3-2, the control unit has an embedded optimization algorithm to find the best combination of two variable capacitors in the adjustable circuit module (5) at a fixed target operating frequency so that the voltage standing wave ratio is minimized. The variable capacitors are C1 and C2. Then, the variable capacitors are sent to the adjustable circuit module through the adjustable control signal transmission path. S3-3, After the parameters are changed, a fixed-point measurement is performed again at the target operating frequency to obtain a new voltage standing wave ratio (VSWR). The control unit compares the newly measured VSWR with the maximum allowable VSWR: if the VSWR > the maximum allowable VSWR, the process returns to step S3 for the next iteration optimization; if the VSWR ≤ the maximum allowable VSWR, the impedance matching is considered to have reached a satisfactory state, the impedance tuning process is successfully completed, and the optimal parameters can be locked.

[0012] As an optional embodiment, the impedance tuning process in the impedance tuning stage employs a gradient descent and alternating optimization algorithm, which specifically includes: S3-2-1: Using the capacitor state after frequency tuning ends as the search starting point, measure the current voltage standing wave ratio as the reference value; S3-2-2: Gradient detection: Adjust the positive and negative ΔC of each variable capacitor in turn, measure the voltage standing wave ratio after adjustment, and determine the optimization direction of each variable capacitor by comparison; S3-2-3: Decision and Execution: Based on the optimization direction of each variable capacitor, a new set of capacitor control instructions is generated; an alternating optimization strategy is adopted, prioritizing the movement of one step along the dimension that brings the maximum improvement in voltage standing wave ratio, fixing that dimension, and then optimizing another dimension. S3-2-4: Iteration and Convergence: Repeat the above process until the voltage standing wave ratio meets the requirements, the gradient in all directions is less than the preset minimum gradient, or the maximum number of iterations is reached.

[0013] As an optional embodiment, in step S3-2-2, if the voltage standing wave ratio in both directions is greater than or equal to the reference value, it is determined that the capacitor is in the flat region at the current point, and its current value remains unchanged in this iteration. Beneficial effects

[0014] (1) Paradigm shift from “passive connection” to “active processing”: This invention breaks through the limitation of traditional adapters as only physical connection mediums. Through the built-in adjustable circuit, it makes it an active element with signal processing capabilities, realizing in-situ reconstruction and performance optimization of RF link functions.

[0015] (2) High system integration and flexibility: Integrating one or more RF functional devices into the adapter significantly saves PCB board area and simplifies system design. Through electronic control, one adapter can replace multiple fixed-function adapters or discrete devices, realizing hardware as software and greatly improving the configuration flexibility of the RF front end.

[0016] (3) Empowering advanced communication systems: This invention is particularly suitable for advanced systems that require frequent frequency band switching, beamforming, or channel awareness, such as 5G / 6G Massive MIMO antenna arrays, cognitive radio, software-defined radio, etc., providing these systems with high-density, reconfigurable RF interconnect solutions; (4) Through its unique closed-loop control mechanism, the resonant frequency of the antenna system is first coarsely adjusted to quickly align with the target operating frequency. Then, the impedance matching is finely adjusted on this basis. The embedded optimization algorithm automatically and accurately finds the best combination of variable capacitors in the adjustable circuit module. Through a systematic gradient detection and alternating optimization strategy, the minimum point of voltage standing wave ratio is searched robustly and efficiently in the two-dimensional parameter space, thereby achieving conjugate matching with the RF source impedance at the target operating frequency. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the internal structure corresponding to Embodiment 1 of the present invention; Figure 2 This is a schematic diagram of the internal structure corresponding to Embodiment 2 of the present invention; Figure 3 This is an overall schematic diagram of the application of Embodiment 1 of the present invention; Figure 4 This is a schematic diagram of the fixed matching circuit of the present invention; Figure 5 This is a flowchart of the control logic of the present invention; The attached diagram lists the components represented by each number as follows: 1. Interface mechanism; 2. Inner conductor; 3. Outer conductor; 4. Reconfigurable control signal transmission path; 5. Adjustable circuit module; 6. Detection module; 7. Detection signal transmission path; 8. Adjustable control signal transmission path; 9. Control unit; 10. Fixed matching circuit. Detailed Implementation

[0018] Application Scenarios: In practical applications, RF adapters, as key passive components in RF circuits that enable signal transition, interface conversion, and power transmission, are widely used between antennas and RF front-end modules, between RF cables of different standards, and in test and measurement systems. Their traditional role is that of a passive conduit, with the core function of ensuring low-loss, low-reflection transmission of RF signals at both mechanical and electrical levels. However, the design and function of existing RF coaxial adapters have lagged significantly behind the needs of modern communication systems, and mainly suffer from the following inherent defects and limitations: (1) Single and rigid functions, unable to adapt to the development trend of reconfigurable RF architecture: After the design of traditional RF adapters is finalized, their electrical performance and physical structure are fixed, which means that they can only perform a single, pre-set connection task, becoming a bottleneck that limits the system's flexibility and spectrum utilization; (2) Performance is easily affected by the environment and lacks adaptive compensation capability: In practical applications, the performance of the RF front end is not constant. It will cause the circuit parameters to deviate from the design value due to changes in the external environment or internal environment, which seriously affects the communication quality and connection reliability; (3) Low system integration, hindering the miniaturization process of equipment: In order to realize the function of processing RF signals, multiple discrete functional devices must be connected in series in the RF link, which occupies valuable printed circuit board area and introduces additional connection loss and potential failure points. Meanwhile, complex wiring also increases the risk of electromagnetic interference; (4) High debugging and maintenance costs: During the system production or debugging phase, if the RF channel performance fails to meet the standards due to processing errors, it is usually necessary to redesign and replace the entire adapter or related functional modules, which is cumbersome and costly. During the maintenance phase, it is also impossible to remotely optimize and adjust the RF performance of the equipment deployed on site.

[0019] In the first preferred embodiment, such as Figure 1The following is a simplified implementation of a reconfigurable RF adapter based on a fixed matching circuit. The adapter includes an interface mechanism 1, an inner conductor 2, an outer conductor 3, and a fixed matching circuit 10 located at both ends. The interface mechanism 1 uses a standard RF interface, such as SMA, 2.92mm, or N-type, for mechanical and electrical connection with external RF cables or ports. The interface mechanism 1 can be male or female to ensure compatibility. The inner conductor 2, as the core channel for RF signal transmission, is located at the geometric axis of the shielded cavity formed by the outer conductor 3 and is supported by high-performance insulation. The support component provides fixation and support, and its main function is to efficiently transmit radio frequency signals. The outer conductor 3 forms the external shielding cavity of the adapter, usually made of brass plated with gold or other high-conductivity metal materials, to provide electromagnetic shielding, prevent signal interference and leakage, and form the loop path for radio frequency signals. By using fixed matching circuits 10 with specific topologies and component parameters built into the shielding cavities of different adapters, a series of adapters of different specifications can be fabricated to achieve system reconfiguration. Each such adapter is preset as a dedicated impedance transformer, which can achieve impedance, frequency, and bandwidth tuning. Specifically: By carefully designing the parameters of the reactive components (inductors and capacitors) of the fixed matching circuit 10, the detuning reactance of the antenna at the target frequency can be compensated. Therefore, replacing the adapter can effectively pull the natural resonant frequency of the antenna system to the preset target operating frequency (such as a specific 5G band), achieving precise frequency alignment. By designing fixed matching circuits 10 with different quality factors (Q values), the operating bandwidth of the antenna system can be preset. High Q value circuits can achieve narrowband, high-selectivity matching, which is suitable for fixed channel scenarios; while low Q value circuits can achieve wideband matching, covering the entire target frequency band, thus flexibly adapting to different communication standards and testing requirements. By changing the transformation ratio of the matching circuit, the complex impedance of the antenna under different conditions (such as due to manufacturing errors or environmental changes) can be transformed into a standard 50 ohms, achieving conjugate matching and maximizing power transmission. like Figure 3As shown, in practical applications, such as in the antenna subsystem of a test instrument, when the performance of the RF channel (i.e., impedance, frequency, and bandwidth) fails to meet standards due to manufacturing errors, operators do not need to perform complex electronic tuning. They only need to manually replace the currently connected adapter with another adapter that has a different built-in fixed matching circuit 10. This physical switching method essentially switches the matching circuit from one preset state to another discretely. This solution can quickly and reliably enable the antenna to operate in a good matching state in the target 5G frequency band, thereby ensuring efficient transmission and reception of RF signals and ultimately improving the accuracy of the test instrument in signal measurement and transmission, as well as the overall stability of the communication link. At the same time, this solution has outstanding engineering application advantages due to its simple structure, low cost, and high reliability.

[0020] like Figure 4 As shown, a specific matching circuit implementation scheme for an adjustable RF adapter is provided. The fixed matching circuit 10 is a Π-type lumped parameter matching network, which is integrated into a shielded cavity composed of an outer conductor 3 and connected in series in the RF signal transmission path of the inner conductor 2. The two ends of the inner conductor 2 correspond to Port1 (signal input port) and Port2 (signal output port), respectively. The fixed matching circuit 10 is composed of a first inductor L1, a second inductor L2, a first capacitor C1, and a second capacitor C2. Its topology is as follows: A first inductor L1 and a second inductor L2 are connected in series between the signal input port Port1 and the signal output port Port2, forming the backbone transmission path of the radio frequency signal. The end of the first inductor L1 closest to the signal input port Port1 is connected to one end of a first capacitor C1, and the other end of the first capacitor C1 is grounded. The other end of the first inductor L1 is connected in parallel with one end of the second inductor L2 and then connected to one end of the second capacitor C2, the other end of the second capacitor C2 is grounded, and the other end of the inductor L2 is connected to the signal output port Port2. This specific topology and its component parameter combination, after precise simulation and optimization, is configured to provide optimal impedance transformation for a specific antenna load at a predetermined target operating frequency (e.g., the 3.5GHz 5G band). Its function is to effectively convert the complex impedance of the antenna into a state conjugate-matched with the impedance of the radio frequency source (typically 50 ohms), thereby significantly reducing the voltage standing wave ratio (VSWR) and achieving efficient transmission of the radio frequency signal. Those skilled in the art should understand that the specific parameter values ​​of the above-mentioned components can be adaptively adjusted according to different target frequencies, antenna impedances and bandwidth requirements, and such matching network designs based on the Π-shaped topology disclosed in this invention all fall within the protection scope of this invention.

[0021] In the second preferred embodiment, such as Figure 2As shown: An adjustable RF adapter with reconfigurable circuitry, its core lies in upgrading the traditional passive adapter structure into an intelligent active system integrating detection, control, and execution functions. The adapter includes an interface mechanism 1 at both ends, an inner conductor 2, an outer conductor 3, a reconfigurable control signal transmission path 4, an adjustable circuit module 5, a detection module 6, a detection signal transmission path 7, an adjustable control signal transmission path 8, and a control unit 9. The interface mechanism 1 adopts a standard RF interface form, such as SMA, 2.92mm, or N-type, for mechanical connection and electrical interface with external RF cables or ports. The interface mechanism 1 can be male or female to ensure compatibility. The inner conductor 2, as the core channel for RF signal transmission, is located at the geometric axis of the shielded cavity formed by the outer conductor 3. The adapter is fixed and supported by high-performance insulating supports, whose main function is to efficiently transmit radio frequency signals. The outer conductor 3 forms the external shielding cavity of the adapter, usually made of brass plated with gold or other high-conductivity metal materials, to provide electromagnetic shielding, prevent signal interference and leakage, and form the loop path of radio frequency signals. The reconfigurable control signal transmission path 4 is a miniaturized flexible circuit board or miniature coaxial cable, used to receive external commands and transmit them to the adjustable circuit module 5, to realize the switching of functions of the external adjustable circuit module 5. The adjustable circuit module 5 is integrated into the sealed cavity formed by the outer conductor 3 and is connected in series or parallel in the radio frequency signal transmission path of the inner conductor 2. In practical applications, the adjustable circuit module 5 can be a combination of one or more functional circuits. Specifically, it can be implemented in any of the following ways: (1) Implementation based on a single type of adjustable element: a. All varactor diode structure: All adjustable reactance elements of the adjustable circuit module are composed of varactor diodes. Its advantage is that it can achieve continuous, analog fine tuning with high tuning accuracy; b. All-switching structure: All adjustable reactance elements are composed of PIN diodes or RF MEMS switches. Their common advantage is that the switching speed is extremely fast, which is suitable for scenarios such as rapid channel transitions; among them, the RF MEMS switch solution also has the unique advantages of extremely low insertion loss, high linearity and quality factor; c. All-integrated circuit structure: All adjustable reactance elements are composed of one or more adjustable capacitor / inductor integrated circuits. Its advantage is that it has the highest integration, the smallest size and is most convenient for digital control, and the system complexity is low. Implementation methods based on hybrid components: a) Combination of adjustable and fixed components: In a Π-type network, adjustable reactive components (varactor diodes, PIN diodes, MEMS switches) and fixed inductors and capacitors together form a matching circuit. This is the most common and efficient engineering implementation. b) Cooperative combination of dissimilar adjustable components: Different types of adjustable components are mixed in the same matching circuit to achieve complementary performance. Example 1: Combination of continuous tuning and fast switching: One branch uses varactor diodes for continuous fine tuning, while another branch uses PIN diodes for fast coarse tuning of frequency bands or states, achieving both high precision and high speed. Example 2: Combination of low-loss coarse tuning and fine tuning: Low-loss coarse tuning is performed using RF MEMS switches (e.g., switching the basic matching circuit), and then fine tuning is performed using varactor diodes based on the coarse tuning, achieving both low loss and high precision. The detection module 6 is also integrated into the shielded cavity. Its input terminal is connected to the inner conductor 2 in a coupled manner. It is used to detect the parameters of the radio frequency signal in real time, such as the impedance matching status of the circuit and frequency changes. The detection signal transmission path 7 is a miniaturized flexible circuit board or a miniature coaxial line, which is used to transmit the analog or digital signals collected by the detection module 6 to the control unit 9 for decision-making. The adjustable control signal transmission path 8 is a flexible circuit board or a miniature coaxial line, which is used to receive the signal transmitted from the detection module 6 to the control unit 9. The control unit 9 is integrated into the cavity formed by the outer conductor 3. It is a miniaturized module containing a microprocessor or dedicated logic circuit. It is responsible for receiving and processing the signals from the detection module 6, running the built-in intelligent algorithm, and sending precise control signals to the adjustable circuit module 5. This invention presents a schematic diagram of the internal structure of an adjustable RF adapter with reconfigurable circuitry. The diagram clearly reveals the spatial layout and interconnection of each functional module within a cylindrical shielded cavity formed by the outer conductor 3. Specifically: the inner conductor 2 serves as the core RF channel, running through the axial center of the adapter; the adjustable circuit module 5 is integrated in series with the inner conductor 2 via a microstrip line and fixed tightly against the inner wall of the cavity to ensure good heat dissipation and mechanical stability; the detection module 6 adopts a directional coupler structure, with its coupling arms arranged adjacent to the inner conductor 2 in a weak capacitive or inductive coupling manner to achieve non-invasive, highly directional detection of forward and reflected power, while minimizing the impact on the main RF path; the control unit 9 is a control board integrating a microprocessor, analog-to-digital converter, and digital interface, installed in a reserved mounting area at one end of the cavity; the detection signal transmission path 7 and the adjustable control signal transmission path 8 are both precision-designed miniature flexible circuit boards, achieving low-noise, high-isolation electrical interconnection between the control unit 9, the detection module 6, and the adjustable circuit module 5.

[0022] In the third preferred embodiment, the adjustable circuit module 5 is a Π-type adjustable matching circuit, which consists of two parallel variable capacitor units and a series inductor unit. The variable capacitor unit adopts a silicon-based digital adjustable capacitor chip. By receiving instructions from the control unit 9, it realizes precise and discrete step adjustment of the capacitance value, thereby achieving adjustment of the antenna frequency and impedance.

[0023] In the fourth preferred embodiment, the detection module 6 includes a directional coupler and a pair of detector chips respectively connected to its positive and negative ports. The detectors convert the coupled radio frequency signal power into a DC voltage signal and transmit it to the control unit 9 through the detection signal transmission path 7; In the fifth preferred embodiment, such as Figure 5 As shown, the intelligent control process applied to the adjustable RF adapter is as follows: S1: The control unit 9 is powered on, the default operating parameters are loaded, and the adjustable circuit module 5 is set to the preset initial operating state (such as frequency and impedance adjustable mode) through the reconfigurable control signal transmission path 4. S2: The detection module 6 continuously samples the radio frequency signal transmitted on the inner conductor 2 and transmits the voltage signal characterizing the forward power and reflected power to the control unit 9. A performance target is preset, including the target operating frequency and the maximum allowable VSWR. In practical applications, the maximum allowable VSWR is set to 2.0. The control unit 9 commands the connected radio frequency signal source to scan within a preset frequency range and sequentially output point-frequency signals of different frequencies. At each frequency point during the frequency sweep, the signal source emits a signal of a specific frequency fi, where i is the index of the specific frequency. Simultaneously, the control unit 9 reads two DC voltage signals transmitted from the detection module 6 through the detection signal transmission path 7: the forward power voltage and the reflected power voltage. Based on these two voltage values, the control unit 9 uses a built-in calibration formula to calculate the voltage standing wave ratio at that frequency point fi in real time, denoted as VSWRi. The calibration formula is: VSWRi = (1 + η) / (1 - η), where η is the forward power and reflected power. The reflection coefficient, specifically η = sqrt(forward power voltage / reflected power voltage); after the entire frequency range is scanned, the control unit 9 can obtain a series of data pairs, specifically represented as: (f1,VSWR1), (f2,VSWR2), ... (fi,VSWRi) ..., (fn,VSWRn), and plot a voltage standing wave ratio-frequency curve accordingly. In practical applications, the voltage standing wave ratio-frequency curve usually has a significant dip or valley. The frequencies corresponding to the dip and valley are the points where the antenna reflection is minimal and the efficiency is highest in the current state; identify the lowest point in the voltage standing wave ratio-frequency curve and extract the frequency corresponding to the lowest point as the current resonant frequency; if |current resonant frequency - target operating frequency| > Δf, where Δf is the frequency tolerance, then frequency detuning is determined, and frequency tuning is triggered to optimize the parameters of the adjustable circuit module 5 so that the current resonant frequency approaches the target operating frequency; the specific frequency tuning process is as follows: S2-1, The control unit 9 first sets the adjustable circuit module 5 (a Π-type matching circuit in this embodiment) to a known initial state that covers a wide frequency range. In practical applications, the initial state of the Π-type matching circuit is to set all digital adjustable capacitors to the intermediate value. S2-2, the control unit 9 sends a series of step-by-step control commands to the adjustable circuit module 5 through the adjustable control signal transmission path, causing its equivalent reactance to change regularly. This is equivalent to scanning within a certain frequency tuning range. The specific step-by-step control commands are digital control words that change in a preset order. The sequence covers the effective operating range of the digital adjustable capacitor, and each change is a fixed minimum step or a preset step. Each time a control command is sent, the equivalent reactance of the adjustable circuit module 5 undergoes a discrete and quantized change. The continuous execution of this series of commands is equivalent to a systematic scan within the frequency tuning range of the adapter. Under the capacitor setting at each step, that is, within the stable time after each control command takes effect, the detection module 6 continuously samples the radio frequency signal on the inner conductor 2, measures the forward power and reflected power respectively, and converts them into DC voltage signals, which are then transmitted back to the control unit 9 in real time through the detection signal transmission path 7. S2-3, the internal analog-to-digital converter (ADC) of control unit 9 digitizes the received voltage signal. Based on each set of forward and reflected power data, it quickly calculates the voltage standing wave ratio (VSWR) corresponding to each capacitor setting point. Among all tested capacitor settings, it finds and determines the capacitor combination that minimizes the VSWR value. The frequency corresponding to this minimum VSWR point is the current resonant frequency of the antenna system in the current tuning state. Control unit 9 calculates the new capacitor value combination required to move the resonant point from the current resonant frequency to the target operating frequency using a preset capacitor setting-resonant frequency correspondence model. The calculated new capacitor value is sent to the digital adjustable capacitor chip in the adjustable circuit module 5 through the adjustable control signal transmission path 8. The digital adjustable capacitor chip precisely adjusts its capacitance value according to the digital instructions. S2-4: After the parameters of the adjustable circuit module 5 are updated, the frequency tuning process is not immediately exited. Instead, a rapid frequency sweep measurement is performed again to confirm whether the new current resonant frequency has entered the tolerance range of the target operating frequency ±Δf. If so, the frequency tuning process is successfully completed and automatically enters the next stage, i.e., step S3 is executed; if not, it returns to step S2 and performs a new round of more refined frequency sweep and adjustment until the frequency condition is met. In practical applications, the current resonant frequency usually converges after 1-2 iterations. S3: After frequency tuning is completed, or when the current resonant frequency meets the requirements, extract the measured VSWR at the target operating frequency. If the measured VSWR at the target operating frequency is greater than the maximum allowable VSWR, then determine the impedance mismatch, trigger impedance tuning, and further optimize the parameters of the adjustable circuit module (5) to reduce VSWR. The impedance tuning process is as follows: S3-1, the radio frequency source is set or maintained at the target operating frequency. The detection module 6 accurately measures the forward power and reflected power at this single frequency point and calculates an accurate VSWR measured value, which is then fed back to the control unit 9. S3-2, the control unit 9 has an embedded optimization algorithm that finds the optimal combination of two variable capacitors (C1, C2) in the adjustable circuit module 5 (i.e., the Π-type matching circuit) at a fixed target operating frequency to minimize the voltage standing wave ratio; then it sends this optimal combination to the adjustable circuit module 5 through the adjustable control signal transmission path 8; the specific process of outputting the optimal variable capacitor combination is as follows: S3-2-1, the algorithm will use the capacitor state (C1) after the frequency tuning is completed. current C2 current This serves as the starting point for the current search, as it is already in a relatively good state, ensuring rapid convergence for subsequent optimizations. Control unit 9 commands the RF source to transmit a signal at the target operating frequency and reads the data returned by detection module 6 to calculate the current voltage standing wave ratio (VSWR). baseline This will serve as the benchmark for subsequent optimization decisions; S3-2-3, Control unit 9 sends a small incremental command to capacitor C1 via adjustable control signal transmission path 8, for example, C1 new =C1 current +ΔC (ΔC is a preset, small capacitance step value), keep capacitor C2 unchanged, and immediately measure the voltage standing wave ratio (VSWR) again after adjusting capacitor C1, and record it as VSWR. C1plus Comparison of VSWR C1plus With VSWR baseline If VSWR C1plus ≤VSWR baseline This indicates that adjusting in the direction of increasing C1 is effective and generates a positive gradient; therefore, the direction of increasing C1 is recorded as the optimization direction for capacitor C1; if VSWR C1plus >VSWR baseline This indicates that the direction is incorrect; therefore, a negative probe is performed, resetting C1 as the search starting point, i.e., C1. current Then, it adjusts in the opposite direction; that is, control unit 9 sends a small reduction command to C1 through adjustable control signal transmission path 8, and C1... new =C1 current -ΔC, and then measure VSWR again. C1minus Comparison of VSWR C1minus With VSWR baseline If VSWR C1minus ≤VSWR baselineThis indicates that decreasing C1 is the correct optimization direction, so record the direction of C1 reduction as the optimization direction for C1. If the voltage standing wave ratio (VSWR) in both directions is greater than or equal to the reference value, it means that the current point is in a flat region, so mark C1 as not needing adjustment at the current point. Similarly, after determining the optimization direction of C1, restore the capacitor to the search starting point, i.e., (C1) current C2 current Keeping C1 unchanged, we perform the same exploratory adjustments and direction judgments on C2 to obtain the optimal direction of C2; S3-2-3, based on the optimization directions of C1 and C2, through (1) C1 next =C1 current +Direction C1 *StepSize C1 (2) C2 next =C2 current +Direction C2 *StepSize C2 Generate a new set of capacitors, where Direction C1 and Direction C2 The sign (+1, -1, or 0) is derived from the trial results, indicating the optimization direction. StepSize is a fixed ΔC. The improvement in voltage standing wave ratio (VSWR) brought about by adjusting C1 and C2 is compared. Prioritizing the movement along the dimension that brings the greatest improvement (e.g., C1), a step size is moved. This new C1 is then fixed, and gradient probing optimization is performed again on C2, forming an alternating optimization process. This approach is more robust during regulation and less prone to oscillations on complex response surfaces. (C1...) next C2 next The new and precise capacitor control commands are encapsulated as capacitor control instructions. The control unit 9 sends these new and precise capacitor control commands to the adjustable circuit module 5 for execution through the adjustable control signal transmission path 8. After S3-2-4 executes the new instruction, the process returns to step S3-1. Under the new capacitor setting, the voltage standing wave ratio (VSWR) of V is measured, forming a loop process of detection, decision-making, execution, and measurement. The process converges successfully when one of the following conditions is met: (1) The measured VSWR is ≤ the maximum allowable VSWR; (2) The gradients of all optimization directions are close to zero (i.e., less than the preset minimum gradient). No matter which direction C1 and C2 are finely adjusted, the VSWR cannot be significantly reduced. At this point, it is considered that the local optimum under the current environment has been found and the parameter is locked; (3) The preset maximum number of iterations is reached to prevent infinite loops. Through a systematic, data-driven closed-loop search process, the unknown impedance response surface is explored by actively and regularly perturbing the data. The next search direction is intelligently determined based on real-time feedback performance indicators, forming a fully automatic, high-precision, and repeatable digital algorithm execution, which fundamentally realizes the intelligence and self-adaptation of RF matching.

[0024] S3-3, After the parameters are changed, a fixed-point measurement is performed again at the target operating frequency (i.e., step S2) to obtain a new voltage standing wave ratio (VSWR). The control unit 9 compares the newly measured VSWR with the maximum allowable VSWR: if the VSWR > the maximum allowable VSWR, the process returns to step S3 for the next iteration optimization; if the VSWR ≤ the maximum allowable VSWR, the impedance matching is considered to have reached a satisfactory state, the impedance tuning process is successfully completed, and the optimal parameters can be locked. Specifically, locking the optimal parameters is as follows: the control unit 9 will lock the capacitor combination of the current adjustable circuit module 5 to the optimal operating state and record it in the non-volatile memory for direct recall next time. By further fine-tuning the parameters of the adjustable circuit module 5 based on the current resonant frequency already aligned with the target operating frequency, an impedance that is conjugate matched with the RF source impedance is presented at the antenna port, thereby reducing the voltage standing wave ratio to below the preset target at the target operating frequency point. S4, the above process can be iterated until the frequency and VSWR requirements are met simultaneously. After stabilization, the control unit 9 enters a low-power monitoring mode to periodically check the system status in order to cope with possible environmental changes and achieve full life cycle self-adaptation. Through the deep integration of the above hardware architecture and control logic, this invention successfully transforms a traditional RF adapter into an adaptive RF control node with real-time sensing, intelligent decision-making and precise execution capabilities, fundamentally solving the industry problem that traditional solutions have fixed functions and cannot cope with dynamic changes. Based on the deep integration of the aforementioned hardware architecture and control logic, the intelligent control module implemented in this invention brings multiple significant benefits: it successfully transforms a traditional passive RF adapter into an adaptive RF control node with real-time sensing, intelligent decision-making, and precise execution capabilities. Through its unique closed-loop control mechanism, it first coarsely adjusts the resonant frequency of the antenna system to quickly align it with the target operating frequency. Then, based on this, it finely adjusts the impedance matching, automatically and accurately finding the optimal combination of variable capacitors in the adjustable circuit module using an embedded optimization algorithm. Through a systematic gradient probing and alternating optimization strategy, it achieves robustness and high efficiency in the two-dimensional parameter space. By effectively searching for the minimum voltage standing wave ratio (VSWR) point, a conjugate match with the RF source impedance is achieved at the target operating frequency. This fully automatic, data-driven process fundamentally overcomes the inherent defects of traditional solutions that rely on engineer experience and manual operation, have fixed functions, and cannot respond to dynamic changes. It not only improves the accuracy, efficiency, and repeatability of tuning and ensures the quality of RF signal transmission and the stability of the communication link, but also endows the system with the ability to autonomously adapt to environmental changes (such as impedance changes caused by temperature drift or the proximity of objects) throughout its entire life cycle. Ultimately, this results in a significant improvement in the performance of communication equipment, a substantial reduction in maintenance costs, and a comprehensive enhancement of the overall system reliability.

[0025] The above are merely preferred embodiments of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions falling within the scope of the present invention's concept are within the scope of protection of the present invention. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principles of the present invention should also be considered within the scope of protection of this template.

Claims

1. A reconfigurable circuit adjustable radio frequency switch, comprising: Interface mechanism (1) is arranged at both ends of the adjustable radio frequency adapter; inner conductor (2) is arranged at the center of the shielding cavity formed by outer conductor (3) as a radio frequency signal transmission channel; outer conductor (3) forms a shielding cavity for providing electromagnetic shielding and forming a loop path of the radio frequency signal; characterized in that the shielding cavity is internally provided with a fixed matching circuit (10) for tuning the impedance, frequency and bandwidth of the antenna.

2. A reconfigurable circuit adjustable radio frequency transceiver according to claim 1, wherein, The fixed matching circuit (10) comprises a signal input port Port1, a first inductor L1, a second inductor L2, a first capacitor C1, a second capacitor C2 and a signal output port Port2; the first inductor L1 and the second inductor L2 are connected in series between the signal input port Port1 and the signal output port Port2 to form the main transmission path of the radio frequency signal; wherein one end of the first inductor L1 close to the signal input port Port1 is connected with one end of the first capacitor C1, and the other end of the first capacitor C1 is grounded; the other end of the first inductor L1 is connected with one end of the second inductor L2 after being connected in parallel, and the other end of the second inductor L2 is connected with one end of the second capacitor C2, and the other end of the second capacitor C2 is grounded.

3. A reconfigurable circuit adjustable radio frequency transceiver according to claim 1, wherein, Further comprising: Reconfigurable control signal transmission path (4) for receiving external instructions and transmitting to adjustable circuit module (5); Adjustable circuit module (5) integrated in the shielding cavity and connected in series or parallel in the radio frequency signal transmission path of the inner conductor (2) for receiving external signals and realizing adjustment of radio frequency parameters; Detection module (6) integrated in the shielding cavity for real-time detection of the parameters of the radio frequency signal; Control unit (9) integrated in the shielding cavity for receiving and processing signals of the detection module (6) and running the built-in intelligent control algorithm; Detection signal transmission path (7) connecting the detection module (6) and the control unit (9); Adjustable control signal transmission path (8) connecting the control unit (9) and the adjustable circuit module (5).

4. A reconfigurable circuit tunable RF switch according to claim 3, wherein, The interface mechanism (1) is used to realize mechanical and electrical connection with external radio frequency ports, the detection signal transmission path (7) is used to transmit detection signals, and the control unit (9) is configured to: based on the signals fed back by the detection module (6), dynamically adjust the parameters of the adjustable circuit module (5) through closed-loop control logic, so that the connected load is on the target working frequency to realize impedance matching.

5. A reconfigurable circuit tunable RF switch according to claim 4, wherein, The adjustable circuit module (5) is one or more of a varactor diode, a PIN diode, a radio frequency MEMS switch or an adjustable capacitor / inductor integrated circuit.

6. A reconfigurable circuit tunable RF switch according to claim 5, wherein, The detection module (6) comprises a directional coupler and a pair of detector chips connected to the forward coupling port and the reverse coupling port of the directional coupler respectively; the coupling arm of the directional coupler is arranged adjacent to the inner conductor (2) in a capacitive coupling or inductive coupling manner.

7. A reconfigurable circuit adjustable radio frequency switch according to claim 6, wherein, The control unit (9) executes the following intelligent control process: S1: system initialization, set the adjustable circuit module (5) to the preset initial state; S2: frequency tuning stage: the control unit (9) determines the current resonant frequency of the load by analyzing the voltage standing wave ratio-frequency curve obtained by the sweep measurement; if the difference between the current resonant frequency and the target operating frequency exceeds the frequency tolerance Δf, the frequency tuning process is triggered, and the current resonant frequency is made to approach the target operating frequency by adjusting the parameters of the adjustable circuit module (5); S3: impedance tuning stage: after the frequency tuning is completed or the current resonant frequency has met the requirements, if the measured voltage standing wave ratio at the target operating frequency is greater than the maximum allowed standing wave ratio, the impedance tuning process is triggered; S4: parameter locking and state guardianship: when the frequency and voltage standing wave ratio requirements are met at the same time, the optimal parameters of the adjustable circuit module (5) are locked.

8. A reconfigurable circuit tunable RF switch according to claim 7, wherein, The frequency tuning process specifically includes: S2-1: set the adjustable circuit module (5) to an initial state covering a wide frequency range; S2-2: send a series of step-by-step control instructions to the adjustable circuit module (5) to make the equivalent reactance change regularly, and after each step of control instruction takes effect, measure the corresponding forward power and reflected power through the detection module (6); S2-3: calculate the voltage standing wave ratio corresponding to each capacitor setting point according to the measurement data, find the capacitor combination that makes the voltage standing wave ratio minimum, and the frequency corresponding to this capacitor combination is the current resonant frequency; based on the pre-set capacitor setting-resonant frequency corresponding relationship model, calculate a new capacitor value combination and issue it to the adjustable circuit module (5); S2-4: verify whether the new current resonant frequency enters the tolerance range of target operating frequency ± Δf, if not, return to step S2-2 for iteration.

9. A reconfigurable circuit adjustable radio frequency switch according to claim 8, wherein, The impedance tuning process specifically includes: S3-1, the radio frequency source is set or maintained at the target operating frequency, the detection module (6) accurately measures the forward power and reflected power at this single frequency point, and calculates an accurate VSWR measured value, which is fed back to the control unit (9); S3-2, the control unit (9) embedded optimization algorithm finds the best combination of two variable capacitors C1 and C2 in the adjustable circuit module (5) at the fixed target operating frequency, so that the voltage standing wave ratio reaches the minimum, and then issues it to the adjustable circuit module (5) through the adjustable control signal transmission path (8); S3-3, after the parameters are changed, the fixed-point measurement is performed again at the target operating frequency to obtain a new voltage standing wave ratio, and the control unit (9) compares the newly measured voltage standing wave ratio with the maximum allowed standing wave ratio: if the voltage standing wave ratio > the maximum allowed standing wave ratio, the process returns to step S3 for next iteration optimization; if the voltage standing wave ratio ≤ the maximum allowed standing wave ratio, it is considered that the impedance matching has reached the target state, and the impedance tuning process is successfully completed, that is, the optimal parameters are locked.

10. A reconfigurable circuit adjustable radio frequency switch according to claim 9, wherein, The impedance tuning process in the impedance tuning stage adopts gradient descent and alternating optimization algorithm, which specifically includes: S3-2-1: take the capacitor state after the frequency tuning is completed as the search starting point, and measure the current voltage standing wave ratio as the reference value; S3-2-2: Gradient detection: Adjust the positive and negative ΔC of each variable capacitor in turn, measure the adjusted voltage standing wave ratio, and determine the optimization direction of each variable capacitor by comparison; S3-2-3: Decision and execution: Based on the optimization direction of each variable capacitor, a new set of capacitor control instructions is generated; an alternating optimization strategy is adopted, and a step is moved along the dimension that can bring the largest voltage standing wave ratio improvement, and after fixing this dimension, another dimension is optimized; S3-2-4: Iteration and convergence: Repeat the above process until the voltage standing wave ratio meets the requirements, all direction gradients are less than the preset minimum gradient, or the maximum number of iterations is reached.

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