Efficiency optimization method of mobile terminal antenna based on signal path separation

Abstract

The invention relates to the technical field of mobile communication, and particularly discloses a mobile terminal antenna efficiency optimization method based on signal path separation, which solves the problem of compromise of antenna transceiving performance through collaborative design of a physical domain and a circuit domain. In a physical domain, a frequency selection type artificial electromagnetic metasurface is integrated in a near field of an antenna, and the frequency selection type artificial electromagnetic metasurface presents a high wave transmission characteristic for an uplink transmitting frequency band signal so as to form a first physical signal path and presents a reflection or waveguide characteristic for a downlink receiving frequency band signal so as to form a spatially isolated second physical signal path. In a circuit domain, a reconfigurable multi-state impedance matching network controlled by a solid-state switch is connected to an antenna feed port. Acquiring a working mode instruction in real time through a control unit, and controlling a network to be switched to a first topological state in conjugate matching with a first path in a transmitting state so as to maximize transmitting efficiency; and switching the receiving state to a second topological state which is in conjugate matching with the second path so as to optimize the receiving sensitivity and the noise coefficient. According to the invention, independent dynamic optimization of physical isolation and impedance of receiving and transmitting paths is realized, and the efficiency of an antenna system is remarkably improved.

Description

Technical Field

[0001] This invention relates to the field of antenna technology, and in particular to an efficiency optimization method for mobile terminal antennas based on signal path separation. Background Technology

[0002] With the rapid development of mobile communication technology, modern mobile terminals (such as smartphones, tablets, and portable routers) need to support an increasing number of communication frequency bands and standards (such as 4G LTE, 5G NR Sub-6GHz and millimeter wave, Wi-Fi 6 / 7, etc.) and integrate multi-antenna systems (such as MIMO, carrier aggregation antennas, etc.) to improve data throughput and connection reliability. This trend poses a severe challenge to the design of terminal antennas: antennas must achieve multi-band, high-efficiency, and low-coupling radiation performance within extremely limited physical space, while also taking into account the impact of practical factors such as the overall industrial design of the device, metal frames, and human grip.

[0003] Traditional mobile terminal antenna designs (such as inverted-F antennas, monopole antennas, and slot antennas) primarily match the target frequency band by adjusting the antenna's geometry and feed position. However, in a compact space, strong mutual coupling often exists between multiple antenna elements or multiple resonant modes of a single antenna element, leading to decreased antenna efficiency and narrowed bandwidth. Furthermore, in time-division duplex (TDD) systems, the uplink (transmit) and downlink (receive) of the antenna share the same physical channel, but their optimal operating states may conflict: during transmission, maximizing power transfer efficiency is needed to reduce power consumption and RF front-end stress; during reception, optimizing noise matching is required to improve sensitivity and signal-to-noise ratio. Traditional fixed impedance matching networks can only offer a compromise, making it difficult to simultaneously optimize transmit and receive performance.

[0004] To improve antenna performance, various methods have been introduced in existing technologies:

[0005] Reconfigurable antenna technology: By dynamically changing the physical structure or resonant circuit of the antenna through switches (such as PIN diodes, RF MEMS) or variable reactance components (such as varactor diodes), the operating frequency band or radiation pattern can be switched. However, its control logic is mostly concentrated in the antenna itself, and its ability to regulate the near-field electromagnetic environment is limited.

[0006] Artificial electromagnetic metasurfaces (METS) are two-dimensional artificial structures composed of periodically arranged subwavelength units. METS enable flexible manipulation of electromagnetic wave amplitude, phase, and polarization. Existing research has applied them to radomes or near-field regions to enhance antenna gain, extend bandwidth, or reduce specific absorptivity (SAR). However, current applications largely focus on passive performance enhancements in single or wide frequency bands, lacking the ability to actively and selectively control different signal paths in complex multi-band, multi-mode scenarios.

[0007] Adaptive impedance matching technology: An adjustable matching network (such as an adjustable capacitor / inductor array) is inserted between the antenna port and the RF front end. The network state is adjusted in real time by detecting parameters such as the reflection coefficient to compensate for mismatch caused by environmental changes (such as the proximity of a person's hand or head). However, most existing solutions only perform overall impedance compensation at the circuit port and do not coordinate with the physical field distribution in the near-field region of the antenna for design and optimization.

[0008] In summary, existing technologies have their own limitations when dealing with the high efficiency and high isolation requirements of multi-band mobile terminal antennas, especially when optimizing the independent transmission and reception performance in time-division duplex systems: either they lack effective separation and control of the physical propagation path of the signal, or they fail to deeply coordinate circuit matching and near-field modulation. Summary of the Invention

[0009] In order to solve the above-mentioned technical problems, the present invention provides an efficiency optimization method for mobile terminal antennas based on signal path separation.

[0010] The technical solution of this invention is implemented as follows:

[0011] This invention provides an efficiency optimization method for mobile terminal antennas based on signal path separation, which achieves intelligent separation and matching of signal paths through collaborative design of the physical domain and the circuit domain.

[0012] The method includes the following steps:

[0013] In the physical domain signal path spatial separation stage, a specially designed frequency-selective artificial electromagnetic metasurface is integrated within the near-field radiation region of the antenna radiating element. This metasurface is composed of subwavelength-scale units arranged at a specific period. By precisely designing its unit structure and arrangement, it exhibits low-loss, high-transmission characteristics for electromagnetic waves in the first target communication frequency band where the mobile terminal operates, thus forming a first physical signal path for efficient radiation of transmitted energy. Simultaneously, it exhibits strong reflection or specific surface wave / waveguide propagation characteristics for electromagnetic waves in the second target communication frequency band where the mobile terminal operates, thereby guiding and forming a second physical signal path that is physically isolated from the first physical signal path. Preferably, this path separation can further lead to a controllable deflection or deformation of the antenna's radiation pattern in both transmitting and receiving states, which is beneficial for isolation.

[0014] During the circuit-domain dynamic impedance matching tuning stage, a reconfigurable multi-state impedance matching network is connected between the feed port of the antenna radiating element and the RF front-end circuit. This network contains at least two switchable branches composed of lumped or distributed parameter passive components, and utilizes at least one controlled solid-state switching element to change the overall topology of the network.

[0015] In the intelligent collaborative control phase based on operating modes, a control unit acquires or detects operating mode commands, which characterize the current wireless communication state, issued by the baseband processing unit in real time. The control unit pre-stores a multi-dimensional lookup table, indexed by information such as operating frequency band, communication standard, and transmit power level, storing the optimal matching network configuration code and switching control sequence.

[0016] When the command instructs the terminal to enter the transmit state, the control unit generates a first set of control signals to drive the switching elements in the matching network to switch to a first preset topology state. The network impedance in this state has been pre-optimized for the antenna input impedance of the first physical signal path in the transmit frequency band, aiming to achieve conjugate matching and thus maximize power transmission efficiency.

[0017] When the command instructs the terminal to enter the receiving state, the control unit generates a second set of control signals to drive the matching network to switch to a second preset topology state. In this state, the network impedance has been pre-optimized for the antenna input impedance of the second physical signal path in the receiving frequency band, aiming to achieve conjugate matching, thereby maximizing signal reception sensitivity and minimizing the noise figure.

[0018] As a further optimization of the method, after the matching network switching is completed, a closed-loop adaptive optimization step can also be performed: the reflection coefficient of the antenna port is measured in real time through a directional coupler or impedance sensor; if the measured value does not reach the preset optimal threshold, the control unit starts the fine-tuning algorithm to slightly adjust the parameters of the adjustable components in the network or switch to an adjacent alternative network topology until the antenna performance indicators meet the requirements.

[0019] Compared with the prior art, the technical solution provided by the present invention has the following significant advantages:

[0020] It achieves synergy between physical isolation and circuit optimization: by introducing frequency-selective metasurfaces in the near-field region, signal energy from different frequency bands (especially the transmit and receive bands) is guided to different spatial paths or field distribution regions at the physical level, fundamentally reducing mutual coupling interference between transmit and receive channels and creating conditions for independent optimization in the circuit domain.

[0021] Dynamically independent optimization of transmit and receive performance is achieved: by utilizing a reconfigurable impedance matching network, the antenna can quickly switch to an impedance matching state specifically optimized for the real-time transmit or receive operating mode. This allows the antenna to pursue the highest radiation efficiency during transmission and the best signal reception quality during reception, breaking through the performance trade-offs of traditional fixed designs.

[0022] It possesses intelligent adaptability and robustness: By combining a control unit with pre-stored strategies and real-time sensor feedback, the method can intelligently identify communication scenarios (such as time slots in Time Division Duplex (TDD), frequency points in Frequency Division Duplex (FDD), carrier aggregation configurations, etc.) and automatically execute the optimal path separation and matching tuning strategies. The closed-loop adaptive mechanism further ensures performance stability under the influence of factors such as device tolerances and environmental changes.

[0023] The overall communication efficiency of the system has been improved: the above-mentioned collaborative optimization ultimately translates into higher transmit power efficiency, lower receive noise figure, and better communication link quality, which makes a direct and positive contribution to improving the signal coverage, data transmission rate, and battery life of mobile terminals. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of an efficiency optimization method for mobile terminal antennas based on signal path separation according to the present invention. Detailed Implementation

[0025] The specific implementation process of the present invention will be described in detail below with reference to the technical solution. It should be understood that the embodiments described herein are intended to explain and illustrate the technical path of the present invention, and are not intended to limit the scope of protection of the present invention.

[0026] like Figure 1As shown, this invention aims to provide an efficiency optimization method for mobile terminal antennas based on signal path separation. Through the coordinated efforts of three stages—spatial path separation in the physical domain, dynamic impedance matching in the circuit domain, and intelligent control based on the operating mode—it fundamentally solves the efficiency trade-off problem that exists when mobile terminal antennas are used for both transmission and reception. The goal is to independently and simultaneously maximize the power transmission efficiency in the transmission state and the signal reception sensitivity in the reception state.

[0027] The method includes the following steps:

[0028] In the physical domain signal path spatial separation stage, a frequency-selective artificial electromagnetic metasurface is constructed and integrated within the radiation near-field region of the antenna radiating element. By precisely designing the subwavelength unit structure and its periodic arrangement of the metasurface, it is made to exhibit low-loss, high-transmission characteristics for signals in the first target communication frequency band where the mobile terminal operates, thereby forming a first physical signal path for energy-efficient radiation. Simultaneously, it is made to exhibit strong reflection or specific waveguide propagation characteristics for signals in the second target communication frequency band where the mobile terminal operates, thereby guiding and forming a second physical signal path that is effectively isolated from the first physical signal path in space.

[0029] During the dynamic impedance matching tuning stage in the circuit domain, a reconfigurable multi-state impedance matching network stage is connected between the feed port of the antenna radiating element and the radio frequency front-end circuit. This network includes at least two switchable branches composed of lumped or distributed passive components, and its overall network topology is changed by at least one controlled solid-state switching element.

[0030] In the intelligent collaborative control phase based on the working mode, a control unit acquires or detects in real time the working mode command representing the current wireless communication state issued by the baseband processing unit. When the command instructs the terminal to enter the transmit state, the control unit generates a first set of control signals to drive the switching elements in the reconfigurable multi-state impedance matching network to switch to a first preset topology state. The network impedance in this state is pre-optimized to achieve conjugate matching with the antenna input impedance of the first physical signal path in the transmit frequency band, thereby maximizing power transmission efficiency. When the command instructs the terminal to enter the receive state, the control unit generates a second set of different control signals to drive the matching network to switch to a second preset topology state. The network impedance in this state is pre-optimized to achieve conjugate matching with the antenna input impedance of the second physical signal path in the receive frequency band, thereby maximizing signal reception sensitivity and minimizing noise figure.

[0031] This embodiment is implemented for a mobile terminal comprising an antenna radiating element, an RF front-end circuit, and a baseband processing unit. First, in the physical domain, an artificial electromagnetic metasurface needs to be integrated or directly constructed in the near-field region of the antenna radiator surface, typically within a distance of 0.05 to 0.1 operating wavelengths. This metasurface consists of periodically arranged subwavelength metallic structural units, such as cross-shaped or open-loop units printed on a flexible polyimide substrate, with a unit period much smaller than the operating wavelength. Its structure is designed through precise electromagnetic simulation to ensure high transmittance to the uplink transmission frequency band, forming a low-loss first physical signal path; simultaneously, it exhibits strong reflectivity to the downlink reception frequency band, forming a spatially isolated second physical signal path. Second, in the circuit domain, a reconfigurable matching network needs to be inserted between the antenna feed point and the RF front-end. This network contains at least two switchable branches composed of patch inductors and capacitors or microstrip line segments, and the topology switching is controlled by solid-state switches such as PIN diodes. Finally, in the control domain, the control unit, composed of a microcontroller, needs to monitor in real-time the mode commands issued by the baseband chip through the GPIO or MIPI RFFE interface. When the command is to transmit, the control unit outputs a preset first set of digital signals, driving the switch to switch the matching network to an L-shaped topology optimized for the transmission path; when the command is to receive, it outputs a second set of signals, switching the network to a T-shaped topology optimized for the reception path, thereby achieving real-time conjugate impedance matching.

[0032] The design steps of the frequency-selective artificial electromagnetic metasurface specifically include: optimizing the shape, size, and period of the subwavelength unit using electromagnetic simulation software based on the center frequency and bandwidth of the uplink transmitting frequency band and the downlink receiving frequency band; the unit is designed to be in a non-resonant or anti-resonant state in the transmitting frequency band to achieve wave transmission, and in a strong resonant state in the receiving frequency band to achieve reflection or surface wave guidance.

[0033] In specific implementation, the design and implementation steps of the metasurface are as follows: First, determine the transmit and receive frequency bands that the system needs to support, such as the uplink 3300 MHz to 3400 MHz and downlink 3500 MHz to 3600 MHz of the 5G mobile communication n78 band. Second, use 3D full-wave electromagnetic simulation software such as CST Microwave Studio to build a model including the antenna and metasurface units. Initially, the metasurface units can be square patches or open resonant rings. Third, optimize the unit size, metal linewidth, and unit period through parametric sweep simulation. The design goal is: in the transmit frequency band, adjust the units to a non-resonant or anti-resonant state, allowing electromagnetic waves to pass through the metasurface with an insertion loss of less than 0.5 dB; in the receive frequency band, adjust the units to generate strong magnetic or electrical resonance, at which point the unit is equivalent to a high-impedance surface or supports surface wave modes, producing a reflection phase greater than 120 degrees to the incident wave, thereby confining or guiding energy in the near-field region. Finally, periodically extend the optimized unit structure to generate the metasurface layout for fabrication.

[0034] By adopting the above technical solution, the core design principles and implementation methods of frequency-selective artificial electromagnetic metasurfaces can be specified, ensuring that they can reliably achieve differentiated electromagnetic responses for the transmission and reception frequency bands.

[0035] This invention provides a precise and low-latency working mode recognition mechanism, enabling the control unit to accurately determine whether the terminal is currently in a transmitting or receiving state. This is a logical prerequisite for triggering subsequent impedance network switching and is particularly suitable for complex modern communication systems with multiple standards coexisting.

[0036] The specific steps for acquiring or detecting working mode instructions in real time are as follows: In a time-division duplex system, the uplink and downlink time slot synchronization signals provided by the baseband chip are directly parsed; in frequency-division duplex or carrier aggregation scenarios, logical judgments are made based on the carrier frequency and bandwidth information configured by the baseband, combined with a pre-stored frequency band-mode mapping table.

[0037] In specific implementations, the methods for acquiring and determining the operating mode instructions vary depending on the communication standard. For time-division duplex systems, such as terminals operating in TD-LTE or TDD mode, the implementation is as follows: the hardware interrupt pin of the control unit is directly connected to the time slot synchronization signal output pin of the baseband chip. At the beginning of each radio frame, the baseband chip outputs a pulse sequence containing uplink and downlink configuration information. The control unit parses this sequence to directly and in real-time determine whether the current time slot is an uplink transmit time slot or a downlink receive time slot, thereby achieving nanosecond-level precision synchronization control. For frequency division duplex or carrier aggregation scenarios, the implementation is as follows: the control unit periodically reads the current operating frequency information configured in the baseband processor register through a serial peripheral interface. The control unit internally stores a frequency band mode mapping table, which defines whether each licensed frequency band is an uplink band, downlink band, or duplex band. By looking up the table, the control unit can perform logical judgments to determine whether to optimize the transmit path or the receive path.

[0038] To address the problem of dynamic impedance shift caused by manufacturing tolerances, environmental changes, or user handling, this invention introduces a closed-loop feedback adjustment mechanism based on open-loop preset matching. This ensures that the system can maintain optimal performance stably under various practical application scenarios, thereby improving the robustness and practicality of the method.

[0039] The method further includes a closed-loop adaptive optimization step: after the matching network is switched, the reflection coefficient of the antenna port is measured in real time through a directional coupler or impedance sensor; if the measured value does not reach the preset optimal threshold, the control unit starts a fine-tuning algorithm to slightly adjust the value of the lumped elements in the network or switch to an adjacent alternative network topology until the antenna performance indicators meet the requirements.

[0040] In practical implementation, the closed-loop adaptive optimization step requires the addition of a sensing and decision-making module. Specifically, a miniature directional coupler is integrated at the output of the RF front-end power amplifier or the input of the low-noise amplifier to couple forward and reflected wave signals. The coupled signal is converted to DC voltage by a detector circuit and then sent to the analog-to-digital converter pin of the control unit, thereby calculating the voltage standing wave ratio (VSWR) or reflection coefficient at the antenna port in real time. A performance threshold is preset within the control unit, for example, a VSWR of 1.8 to 1. Each time the matching network topology is switched according to the operating mode command, the control unit reads and judges the current measurement value. If the measurement value is better than the threshold, the current state is maintained. If the threshold is not reached, a fine-tuning algorithm is initiated. One feasible fine-tuning algorithm is gradient descent: the control unit adjusts the bias voltage of an adjustable capacitor in the matching network in small steps according to a predetermined step size to change its capacitance value, and observes the trend of the reflection coefficient change, continuously adjusting in the direction of performance improvement. Another approach is the lookup table method: the control unit pre-stores several neighboring topology configurations and their switching control codes around the main topology state. When the main state performance is poor, it attempts to switch to these neighboring states in turn and selects the one with the best performance as the final configuration.

[0041] The first target communication frequency band and the second target communication frequency band are paired frequency bands under the same communication standard, or independent frequency bands under different communication standards; the artificial electromagnetic metasurface is configured to simultaneously realize the path separation function for multiple frequency band groups.

[0042] The first and second target communication frequency bands can be the 1710 MHz to 1785 MHz uplink band and its corresponding downlink band of Long Term Evolution (LTE) Band 3, forming a frequency division duplex (FDM) pair. Alternatively, they can be independent, unpaired frequency bands, such as the 2400 MHz to 2483 MHz transmit band of WiFi and the 1561 MHz receive band of the Global Navigation Satellite System. To achieve path separation for multiple frequency band groups, more complex designs of artificial electromagnetic metasurfaces are required. Implementation can involve using a multi-layer metasurface structure, with each layer optimized for a specific frequency band group. Alternatively, a single-layer composite unit design with multi-resonance characteristics can be used, such as a nested open-loop or multi-arm star structure, optimized through simulation to exhibit the desired transmission or reflection characteristics at multiple discrete target frequency points. In the circuit domain, the reconfigurable matching network also needs to be designed to switch between a wider range of preset topology states to cover the optimized matching requirements of all target frequency band combinations.

[0043] By adopting the above technical solution, the applicability and compatibility of the present invention can be expanded, enabling it to not only handle paired transmit and receive frequency bands under a single communication standard, but also handle multiple independent frequency bands under different standards, thereby improving the general value of the technology in modern multi-mode multi-frequency terminals.

[0044] The solid-state switching element is a PIN diode, a radio frequency microelectromechanical system switch, or a gallium nitride field-effect transistor switch.

[0045] PIN diode switches offer low implementation costs and microsecond-level switching speeds, making them suitable for mobile terminals where switching speed requirements are not extremely stringent. Their implementation circuitry includes a drive circuit providing forward conduction current and reverse cutoff bias to the PIN diode. RF MEMS switches offer extremely high isolation and linearity with very low power consumption, but may require higher control voltages and specialized packaging. Careful voltage conversion design of the drive circuitry is crucial during implementation. Gallium nitride (GaN) field-effect transistor (FET) switches, on the other hand, provide ultra-fast nanosecond-level switching speeds, high power capacity, and good integration potential, making them a preferred solution for future high-speed communication systems. Their implementation is similar to traditional silicon-based FETs, but requires adaptation to their specific gate drive voltage. In specific circuit board layouts, all switching elements should be placed as close as possible to passive matching components to minimize parasitic effects and ensure proper RF shielding.

[0046] By adopting the above technical solution, the types of solid-state switching elements that can achieve high-speed and reliable network topology switching can be limited and selected, balancing switching speed, power handling capability, linearity and integration, and ensuring that the reconfigurable impedance matching network can meet the real-time requirements of modern high-speed wireless communication.

[0047] In order to build an efficient and scalable decision query mechanism, this invention enables the control unit to quickly retrieve and execute the current optimal impedance matching strategy based on multi-dimensional context information, thereby upgrading from simple state response to intelligent context awareness.

[0048] The control unit has a pre-stored multidimensional lookup table. This table uses the operating frequency band, communication standard, transmission power level, and environmental sensor data as input indexes, and outputs the corresponding optimal matching network topology configuration code and switch control sequence.

[0049] The construction and use of the multidimensional lookup table is the core of implementing intelligent control. This lookup table is implemented in the non-volatile memory of the control unit, such as the flash memory of a microcontroller or an external EEPROM. The input index of the table includes at least: the operating frequency band number, the communication standard identifier, and the transmit power level. More advanced implementations can also incorporate data from terminal environmental sensors as indexes, such as proximity sensor signals to determine if the phone is being held, or inertial measurement unit signals to determine the device's attitude. The output of the table is the corresponding optimal matching network configuration code, a set of binary sequences that directly defines the on / off state of each switching element in the network. At the end of the production line, each terminal needs to be calibrated: in a fully anechoic chamber, the terminal traverses all important frequency bands, standards, and power level combinations, and an automated program searches for and records the switch configuration code that optimizes antenna efficiency or receiver sensitivity for each combination, ultimately burning it into the lookup table. During real-time operation, the control unit integrates the current frequency band, standard, and power level information to form a composite lookup key, quickly retrieves the corresponding configuration code through a lookup operation, and executes it.

[0050] In order to enhance the effect of physical domain path separation, this invention not only achieves near-field energy isolation, but also extends the separation effect to far-field radiation characteristics. By actively adjusting the radiation pattern of the antenna, interference is avoided in space, thereby providing additional transmit / receive isolation gain at the system level.

[0051] In the step of spatial signal path separation in the physical domain, the path separation achieved by the artificial electromagnetic metasurface allows for a controllable deflection or shape change in the spatial distribution between the antenna's primary radiation pattern in the transmitting state and its optimal reception pattern for the incoming signal in the receiving state. This further reduces the inherent coupling between the transmitting and receiving channels.

[0052] Implementation Details: Achieving controllable deflection of the radiation pattern relies on a more refined design of the metasurface spatial arrangement. The primary approach is to use non-uniform or gradient metasurfaces. For example, instead of using a periodic arrangement where all elements are identical, the element size or rotation angle at different locations on the metasurface varies linearly or as a specific function along a certain direction. This gradient design introduces an additional, spatially varying phase shift. The implementation steps are as follows: First, determine the desired transmit beam deflection angle, for example, a 15-degree upward deflection; then, calculate the required spatial phase distribution of the metasurface using the phase gradient formula; next, through electromagnetic simulation, design the element size gradient arrangement that achieves this phase distribution. After fabrication, the metasurface will bend the wavefront of the transmitted signal passing through it, thereby changing the main radiation direction. For the receiving band, its effective "receiver pattern" may also change due to the reflection or redirection of energy, becoming less sensitive to interference from the sides. In this way, more favorable spatial isolation conditions are physically created for transmitting and receiving signals.

[0053] Although alternative embodiments of this application have been described, those skilled in the art, upon learning the basic inventive concept, can make further changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this application.

[0054] The above specific embodiments further illustrate the purpose, technical solution and beneficial effects of this application. It should be understood that the above are only specific embodiments of this application and are not intended to limit the scope of protection of this application. Any modifications, equivalent substitutions, improvements, etc., made on the basis of the technical solution of this application should be included within the scope of protection of this invention.

Claims

1. A method for optimizing the efficiency of a mobile terminal antenna based on signal path separation, characterized in that, The method includes the following steps: In the physical domain signal path spatial separation stage, a frequency-selective artificial electromagnetic metasurface is constructed and integrated within the radiation near-field region of the antenna radiating element. By designing the subwavelength unit structure and its periodic arrangement of the metasurface, it is made to exhibit low-loss, high-transmission characteristics for signals in the first target communication frequency band where the mobile terminal operates, thereby forming a first physical signal path for energy-efficient radiation. Simultaneously, it is made to exhibit strong reflection or specific waveguide propagation characteristics for signals in the second target communication frequency band where the mobile terminal operates, thereby guiding and forming a second physical signal path that is effectively isolated from the first physical signal path in space. During the dynamic impedance matching tuning stage in the circuit domain, a reconfigurable multi-state impedance matching network stage is connected between the feed port of the antenna radiating element and the radio frequency front-end circuit. This network includes at least two switchable branches composed of lumped or distributed passive components, and its overall network topology is changed by at least one controlled solid-state switching element. In the intelligent collaborative control phase based on the working mode, a control unit acquires or detects in real time the working mode command representing the current wireless communication state issued by the baseband processing unit. When the command instructs the terminal to enter the transmit state, the control unit generates a first set of control signals to drive the switching elements in the reconfigurable multi-state impedance matching network to switch to a first preset topology state. The network impedance in this state is pre-optimized to achieve conjugate matching with the antenna input impedance of the first physical signal path in the transmit frequency band, thereby maximizing power transmission efficiency. When the command instructs the terminal to enter the receive state, the control unit generates a second set of different control signals to drive the matching network to switch to a second preset topology state. The network impedance in this state is pre-optimized to achieve conjugate matching with the antenna input impedance of the second physical signal path in the receive frequency band, thereby maximizing signal reception sensitivity and minimizing noise figure.

2. The method according to claim 1, characterized in that, The design steps of the frequency-selective artificial electromagnetic metasurface specifically include: optimizing the shape, size, and period of the subwavelength unit using electromagnetic simulation software based on the center frequency and bandwidth of the uplink transmitting frequency band and the downlink receiving frequency band; the unit is designed to be in a non-resonant or anti-resonant state in the transmitting frequency band to achieve wave transmission, and in a strong resonant state in the receiving frequency band to achieve reflection or surface wave guidance.

3. The method according to claim 1, characterized in that, The steps for real-time acquisition or detection of working mode instructions are as follows: in a time-division duplex system, the uplink and downlink time slot synchronization signals provided by the baseband chip are directly parsed; in frequency division duplex or carrier aggregation scenarios, logical judgment is made based on the carrier frequency and bandwidth information configured by the baseband, combined with the pre-stored frequency band-mode mapping table.

4. The method according to claim 1, characterized in that, The method further includes a closed-loop adaptive optimization step: after the matching network is switched, the reflection coefficient of the antenna port is measured in real time through a directional coupler or impedance sensor; if the measured value does not reach the preset optimal threshold, the control unit starts a fine-tuning algorithm to slightly adjust the value of the lumped elements in the network or switch to an adjacent alternative network topology until the antenna performance indicators meet the requirements.

5. The method according to claim 1, characterized in that, The first target communication frequency band and the second target communication frequency band are paired frequency bands under the same communication standard, or independent frequency bands under different communication standards; the artificial electromagnetic metasurface is configured to simultaneously realize the path separation function for multiple frequency band groups.

6. The method according to claim 1, characterized in that, The solid-state switching element is a PIN diode, a radio frequency microelectromechanical system switch, or a gallium nitride field-effect transistor switch.

7. The method according to claim 1, characterized in that, The control unit has a pre-stored multidimensional lookup table. This table uses the operating frequency band, communication standard, transmission power level, and environmental sensor data as input indexes, and outputs the corresponding optimal matching network topology configuration code and switch control sequence.

8. The method according to claim 1, characterized in that, In the physical domain signal path spatial separation stage, the path separation achieved through the artificial electromagnetic metasurface allows for a controllable deflection or shape change in the spatial distribution between the antenna's primary radiation pattern in the transmitting state and its optimal reception pattern for the incoming signal in the receiving state, thereby further reducing the inherent coupling between the transmitting and receiving channels.

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