Method for ocean microwave transmission based on automatic tracking mechanism

Abstract

The present application relates to the technical field of wireless communication, and discloses a high-speed offshore long-distance microwave transmission method based on an automatic tracking mechanism, comprising: obtaining a current moment ship transient attitude vector and a sea wave surface instantaneous two-dimensional elevation distribution function; inputting the same into a hydrodynamic deduction model to predict a future moment ship attitude vector and a sea wave reflection surface transient geometric topological deformation after a preset lead time step; calculating a physical layer radio frequency beam pre-alignment attitude compensation angle and microwave channel distortion parameters including a multipath phase difference, a cross-polarization depolarization crosstalk matrix and a Doppler shift component according to the same; and taking the attitude compensation angle and the distortion parameters as feedforward instructions to synchronously issue the same to the physical layer and the baseband layer before the future moment arrives for joint feedforward pre-configuration, and performing demodulation transmission of a high-speed data stream based on the same. The present application effectively overcomes the lag defect of feedback control.

Description

Technical Field

[0001] This invention relates to the field of wireless communication technology, specifically to a marine microwave transmission method based on an automatic tracking mechanism. Background Technology

[0002] High-speed microwave transmission is a crucial component in building long-distance communication networks in near-shore areas. In practical applications, ships carrying communication nodes are constantly exposed to dynamically evolving fluid environments. Sea waves not only force the hull into violent six-degree-of-freedom transient motions but also create irregular, undulating reflection interfaces, posing significant challenges to microwave propagation links due to spatial pointing offset and multipath scattering fading. To maintain data link stability, existing systems typically employ mechanical servo gimbals for beam alignment and integrate adaptive equalizers within the receiver for channel compensation.

[0003] However, existing tracking and demodulation mechanisms generally follow closed-loop feedback control logic based on error extraction. This post-compensation mode has significant physical lag defects when dealing with complex sea conditions. When a ship experiences a sudden attitude change due to transient excitation from waves, traditional servo systems rely on current sensor sampling for calculation. Limited by bus transmission delay, mechanical motor starting inertia, and algorithm processing cycle, by the time the compensation command drives the antenna array to the target position, the ship's hull has often deviated from its original calculated attitude, resulting in unavoidable spatial misses of the radio frequency beam. In this state of physical layer pointing deviation, the sea... The continuous deformation of surface wave topology further exacerbates the polarization distortion and multipath interference of electromagnetic waves, generating strong asymmetric Doppler frequency shift and cross-polarization crosstalk. Faced with sudden channel degradation, the adaptive filter and phase tracking loop in traditional baseband receivers can only rely on the received error signal to perform slow tap weight iteration. Its convergence speed is seriously lagging behind the evolution rate of the physical environment. The superposition of physical layer alignment delay and baseband layer equalization delay causes the constellation diagram decision boundary of digital signals to frequently cross the tolerance threshold under multipath interference, ultimately leading to continuous packet loss and link interruption of high-speed data streams. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a marine microwave transmission method based on an automatic tracking mechanism. This method solves the problem that existing marine microwave communication systems suffer from physical lag due to the closed-loop feedback control mechanism under complex and dynamic sea conditions, leading to antenna beam pointing deviation and slow baseband channel equalization, which in turn causes high-speed data transmission interruptions.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a marine microwave transmission method based on an automatic tracking mechanism, comprising the following steps: Obtain the ship's transient attitude vector at the current moment and the instantaneous two-dimensional elevation distribution function of the sea wave surface in the area covered by the transmission link; The ship's transient attitude vector and the instantaneous two-dimensional elevation distribution function of the wave surface are input into the ship wave coupled hydrodynamics model to predict the ship's attitude vector and the transient geometric topological deformation of the wave reflector at a future moment after a preset lead time step. Based on the predicted ship attitude vector at the future moment and the transient geometric topological deformation of the wave reflector, the attitude compensation angle for physical layer radio frequency beam pre-alignment is calculated, and the microwave channel distortion parameters for baseband compensation are mapped and calculated in the baseband digital domain; the microwave channel distortion parameters include at least one of multipath phase difference, cross-polarization depolarization crosstalk matrix, and Doppler frequency shift component. The attitude compensation angle and the microwave channel distortion parameters are used as feedforward commands and are synchronously sent to the physical layer and baseband layer control unit before the arrival of the future time to perform joint feedforward pre-configuration of radio frequency and baseband, and the demodulation and transmission of microwave high-speed data stream are performed based on the pre-configuration results.

[0006] Furthermore, the process of obtaining the ship's transient attitude vector at the current moment and the instantaneous two-dimensional elevation distribution function of the sea surface in the transmission link coverage area includes: using an inertial measurement unit to collect the ship's roll angle, pitch angle, and bow angle as the ship's transient attitude vector; using microwave radar lead-scattered echo or optical sensors to extract the elevation data corresponding to the orthogonal spatial coordinates of the sea surface around the transmission link, and constructing the instantaneous two-dimensional elevation distribution function of the sea surface.

[0007] Furthermore, the preset lead time step The sum of the mechanical servo delay and baseband processing delay of the microwave transmission system is greater than the mathematical equation for its calculation:

[0008] in, The mechanical servo delay, which represents the physical deflection of the antenna array driven by the microwave transmission system, is calibrated based on the historical test response time of the servo motor's orientation-seeking closed loop. This represents the baseband processing delay during parameter injection and signal demodulation operations performed by the baseband layer control unit, which is calculated based on the instruction execution cycle of the baseband digital signal processing device. This represents the system safety timing margin, which is used to compensate for the uncertain delays introduced by bus communication jitter and system clock asynchrony. Its value is configured as a fixed constant based on historical alignment and synchronization experience data of the microwave link's transmitting and receiving ends.

[0009] The ship wave-coupled hydrodynamic model uses fluid kinematic equations to derive the time evolution of wave elevation, combines the surface velocity vector of wave particles and gradient operators to output the transient geometric and topological deformation of the wave reflector, and synchronously outputs the ship attitude vector at the future moment based on rigid body kinematics and fluid force mapping. The model utilizes the fluid moment matrix. Solve the differential equation for the rigid body rotation of the ship:

[0010] in, Represents the angular acceleration vector of the ship. Represents the ship's angular velocity vector; Represents the angular displacement vector of the ship; The associated mass matrix is ​​obtained through static calibration based on the inherent moment of inertia parameters in the ship's three-dimensional structural design drawings. The damping matrix is ​​generated based on historical measured hydrodynamic coefficients from ship static water free decay tests. This represents the restoring moment coefficient matrix, which is determined by the ship's static stability data.

[0011] Furthermore, the microwave channel distortion parameters include the multipath phase difference. The process of calculating the multipath phase difference includes: determining the coordinates of the sea surface mirror reflection point by combining the height of the transmitting antenna, the height of the receiving antenna, and the horizontal distance between the transmitting and receiving antennas; extracting the predicted elevation of the corresponding coordinates using the transient geometric topological deformation of the wave reflector; and calculating the length of the direct path. With the length of the reflection multipath Based on the difference between the length of the reflected multipath and the length of the direct path, combined with the microwave carrier wavelength... The multipath phase difference predicted by the receiver is derived. :

[0012] Furthermore, the microwave channel distortion parameters include the cross-polarization depolarization crosstalk matrix, the calculation process of which includes: calculating the transient slope normal vector at the predicted reflection point for the wave slope corresponding to the transient geometric topological deformation of the wave reflector; obtaining the depolarization rotation angle caused by geometric deflection by calculating the inner product of the incident microwave wave vector and the transient slope normal vector; and constructing the transient cross-polarization depolarization crosstalk matrix based on the trigonometric function value of the depolarization rotation angle, which maps the interference coefficients between orthogonal polarization channels.

[0013] Furthermore, the microwave channel distortion parameters include the Doppler frequency shift component, and the calculation process includes: extracting the local vertical velocity component at the predicted reflection point to characterize the asymmetry of the deformation rate between the windward and leeward sides of the waves; for any predicted reflection point, the control unit extracts its local vertical velocity component. Combined with microwave carrier frequency speed of light constant and the incident angle of microwaves on the local inclined plane. Calculate the Doppler frequency shift component generated by the multipath signal at this point. The Doppler frequency shift component The mathematical equation is set as follows:

[0014] Furthermore, the joint feedforward pre-configuration of radio frequency and baseband includes beam pre-alignment configuration: converting the predicted ship attitude vector at the future moment into the attitude compensation angle; while the mechanical servo system starts the direction-finding motor according to the attitude compensation angle, the attitude compensation angle is calculated by subtracting the actual mechanical pointing angle of the system in real time to obtain a dynamic mechanical response residual, and the radio frequency phased array is driven to perform beam electrical deflection according to the dynamic mechanical response residual to maintain the main beam peak alignment.

[0015] Furthermore, the joint feedforward pre-configuration of radio frequency and baseband includes channel multipath phase compensation configuration: the multipath phase difference predicted by the receiver is fed forward to the phase synchronization compensation module of the baseband receiver, and a reverse phase rotation vector is preset before the channel distortion occurs to offset the multipath phase distortion caused by the abrupt change in sea surface geometry.

[0016] Furthermore, the joint feedforward pre-configuration of RF and baseband includes feedforward pre-setting of cross-polarization interference canceller coefficients: in the baseband dual-polarization receiver, the predicted cross-polarization depolarization crosstalk matrix is ​​inverted to obtain the feedforward weight matrix of the cross-polarization interference canceller; the feedforward weight matrix is ​​directly injected as the initial tap coefficient of the adaptive equalizer.

[0017] Furthermore, the joint feedforward pre-configuration of RF and baseband includes constellation diagram dynamic pre-distortion configuration: feeding the calculated Doppler frequency shift component forward to the quadrature amplitude modulation soft decision demodulator; dynamically changing the geometric center coordinates of the decision boundary in the demodulation grid according to the single-symbol phase rotation deviation angle caused by the Doppler frequency shift component, and performing asymmetric pre-distortion to suppress inter-symbol interference caused by asymmetric wave motion.

[0018] This invention provides a marine microwave transmission method based on an automatic tracking mechanism. It has the following beneficial effects: 1. This invention relies on the advance time step to extract the carrier attitude at future moments and convert it into a servo compensation angle. The feedforward command is distributed in advance to the mechanical motor and the phased array phase shifter network to perform joint deflection, which cancels the antenna beam spatial pointing deviation caused by the closed loop feedback time, so that the underlying radio frequency alignment action keeps synchronized with the external motion trajectory.

[0019] 2. This invention maps the topological geometric deformation parameters of ocean waves to multipath phase difference and asymmetric Doppler frequency shift, and injects the derived matrix as initial weights across layers into the receiver digital equalizer and soft decision network. Before the electromagnetic wave is fading due to multipath scattering, the complex plane decision boundary coordinates are corrected, thus cutting off the transmission chain from fluid undulations to communication error evolution. Attached Figure Description

[0020] Figure 1 This is a flowchart of the near-shore microwave high-speed transmission method based on an automatic tracking mechanism according to the present invention. Figure 2 This is a schematic diagram of the hardware topology of the microwave communication node system of the present invention; Figure 3 This is a schematic diagram illustrating the timing principle of the preset lead time step mechanism of the present invention; Figure 4 This is a schematic diagram of the geometric topology of the sea surface multipath reflection and microwave link of the present invention; Figure 5 This is a block diagram of the RF and baseband joint feedforward pre-configuration logic of the present invention; Figure 6 This is a schematic diagram of the constellation diagram dynamic pre-distortion decision boundary mapping of the present invention. Detailed Implementation

[0021] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] Please see the appendix Figure 1 To be continued Figure 6 This invention provides a marine microwave transmission method based on an automatic tracking mechanism, comprising the following steps: Obtain the ship's transient attitude vector at the current moment and the instantaneous two-dimensional elevation distribution function of the sea wave surface in the area covered by the transmission link; The transient attitude vector of the ship and the instantaneous two-dimensional elevation distribution function of the wave surface are input into the ship wave coupled hydrodynamic model to predict the ship attitude vector and the transient geometric topological deformation of the wave reflector at a future moment after a preset lead time step. Based on the predicted future ship attitude vector and the transient geometric topological deformation of the wave reflector, the attitude compensation angle for physical layer radio frequency beam pre-alignment is calculated, and the microwave channel distortion parameters for baseband compensation are mapped and calculated in the baseband digital domain. The microwave channel distortion parameters include at least one of multipath phase difference, cross-polarization depolarization crosstalk matrix and Doppler frequency shift component. The attitude compensation angle and microwave channel distortion parameters are used as feedforward commands and are synchronously sent to the physical layer and baseband layer control unit before the arrival of the future moment for joint feedforward pre-configuration of radio frequency and baseband. Based on the pre-configuration results, the high-speed microwave data stream is demodulated and transmitted.

[0023] To achieve feedforward synchronous execution of the above steps, the system establishes a forward prediction mechanism on the time axis. The communication node is equipped with an inertial measurement unit, microwave radar, mechanical servo system, radio frequency phased array, and baseband dual-polarized receiver. During communication, the sensor components continuously and periodically sample the local motion state and the surrounding fluid environment to generate the underlying environmental state characteristics at the current moment.

[0024] To ensure that the calculated compensation parameters accurately apply to the physical instant when channel distortion occurs, the preset lead time step is set strictly according to the lag characteristics of the system hardware processing. The preset lead time step spanned by the prediction model is... The delay is greater than the sum of the mechanical servo delay and the baseband processing delay of the microwave transmission system, and its calculation logic conforms to the following formula:

[0025] in, This parameter represents the mechanical servo delay that drives the antenna array of the microwave transmission system to physically deflect. It is calibrated based on the historical test response time of the servo motor's orientation-seeking closed loop. This represents the baseband processing delay during parametric injection and signal demodulation operations performed by the baseband layer control unit. This parameter is calculated based on the instruction execution cycle of the baseband digital signal processing device. This represents the system safety timing margin, which is used to compensate for the uncertain delays introduced by bus communication jitter and system clock asynchrony. Its value is configured as a fixed constant based on historical alignment and synchronization experience data of the microwave link's transmitting and receiving ends.

[0026] After determining the preset lead time step, the system shifts the discrete-time series forward within the computational domain. The transient attitude vector of the ship acquired by the underlying sensing hardware and the instantaneous two-dimensional elevation distribution function of the sea surface constitute the initial boundary conditions, which are then processed by the hydrodynamic extrapolation computing unit to perform time-domain evolution. This extrapolation process outputs the ship attitude vector and the transient geometric and topological deformation of the sea surface at future moments, thereby transforming the mechanical deflection and multipath abrupt changes in sea surface reflection that have not yet occurred in physical space into a priori predicted quantities in the digital domain.

[0027] After obtaining the aforementioned spatial and geometric predictions, the system's internal parameter mapping mechanism executes two calculation paths in parallel. The first calculation path points to the radio frequency physical layer, converting the ship's attitude vector at future moments into attitude compensation angles for the transmit and receive dual-end antennas, providing spatial pre-aiming basis for the mechanical motors and radio frequency phased arrays; the second calculation path points to the digital baseband layer, using the transient geometric topological deformation of the wave reflector to deduce the polarization and frequency shift state of electromagnetic waves in a multipath propagation environment, thereby generating microwave channel distortion parameters.

[0028] Before the preset lead time step is exhausted, the control bus directly distributes the attitude compensation angle to the mechanical servo system and the radio frequency phased array, and injects the microwave channel distortion parameters into the baseband digital signal processing device. This allows the physical layer array deflection and baseband layer channel equalization to be preset before the channel physical deterioration occurs, thereby maintaining the continuity of microwave high-speed data stream demodulation transmission.

[0029] In this embodiment, the control unit instructs the underlying hardware array to perform spatial and environmental physical quantity acquisition operations; the inertial measurement unit extracts the Euler angle data of the local ship, and contains a three-axis gyroscope and a three-axis accelerometer module, with the microprocessor periodically reading the components of each axis. The inertial measurement unit acquires the roll angle of the local ship. Pitch angle and bow angle As the basic data source, the control unit combines the above angular components to form the ship's transient attitude vector at the current moment. .

[0030] Simultaneously, the microwave radar transmits a preamble detection pulse toward the sea level surrounding the transmission link, and the receiving channel intercepts the preamble scattered echo. The signal processor analyzes the echo's characteristic time and interferometric phase to extract the orthogonal spatial coordinates of the sea level. The corresponding elevation data. Based on the orthogonal spatial coordinates and the corresponding elevation data, the control unit constructs the instantaneous two-dimensional elevation distribution function of the sea wave surface at the current moment. In the event of radar blind spots or data loss, the system switches to the optical sensor for supplementary sampling. The optical sensor is a binocular camera array with its intrinsic and extrinsic parameter matrices pre-acquired using the Zhang Zhengyou calibration method. The image processor extracts the synchronization frames from the left and right cameras and calculates the disparity map of the corresponding pixels using a semi-global block matching algorithm. The system obtains the baseline length. With camera focal length Using the depth conversion formula disparity value Physical depth converted to pixels Furthermore, by using a coordinate system rotation and translation matrix, the depth point cloud in the camera coordinate system is converted into elevation data in the geographic coordinate system, so as to independently construct the instantaneous two-dimensional elevation distribution function of the wave surface.

[0031] After acquiring the initial physical quantities, the control unit will input the ship's transient attitude vector. and the instantaneous two-dimensional elevation distribution function of the ocean wave surface The data is input into the ship wave coupled hydrodynamic model. In this embodiment, the ship wave coupled hydrodynamic model uses fluid kinematic equations to derive the time evolution of wave elevation; this derivation process is based on unsteady flow motion rules, establishing the following spatiotemporal evolution partial differential equation:

[0032] in, Indicates the current time; The gradient operator in two-dimensional space is defined as follows: ; This represents the surface velocity vector of ocean wave particles. The microprocessor, based on linear wave amplitude theory, utilizes the first-order partial derivative of the elevation function with respect to time and the local depth constant. And combined with the gravitational acceleration constant Calculate the surface velocity vector of ocean wave particles. Its mathematical expression is defined as follows:

[0033] The model uses the Runge-Kutta numerical integration method to solve the above fluid kinematic equations in a time-step manner, with the integration time set to a preset lead time step. .

[0034] The inference model combines the surface velocity vector of ocean wave particles. and gradient operator Iterative equations output the transient geometric topological deformation of the wave reflector. This topological deformation characterizes the physical uplift state of the three-dimensional sea-level grid at future moments. The water wave deformation generates mechanical feedback, and the ship wave-coupled hydrodynamic model synchronously outputs the ship's attitude vector at future moments based on rigid body kinematics and fluid force mapping. The model substitutes the transient geometric topological deformation into the Bernoulli equation for integration, thereby generating the fluid torque matrix acting on the hull. .

[0035] The simulation model includes a pre-set correlation mass matrix of the target ship carrier. With damping matrix Correlation quality matrix Static calibration of the damping matrix based on the inherent moment of inertia parameters in the ship's three-dimensional structural design drawings. The model is generated based on historically measured hydrodynamic coefficients from ship still-water free decay tests. The extrapolation model utilizes the fluid force matrix. Solve the differential equations of the rigid body motion of the ship:

[0036] in, Represents the angular acceleration vector of the ship; Represents the ship's angular velocity vector; Represents the angular displacement vector of the ship; The associated mass matrix is ​​obtained through static calibration based on the inherent moment of inertia parameters in the ship's three-dimensional structural design drawings. The damping matrix is ​​generated based on historical measured hydrodynamic coefficients from ship static water free decay tests. The restoring moment coefficient matrix is ​​represented by the ship's static stability data. The derivation model uses a fourth-order Runge-Kutta algorithm to perform integration on this differential equation, setting the iteration time step to 10 milliseconds and the convergence error threshold to 10. 4 Radius; After the integration operation is completed, the system superimposes the ship's transient attitude vector at the current moment. Simultaneously output the ship attitude vector at future moments. This provides a data foundation for subsequent microwave parameter configuration.

[0037] In this embodiment, the system maps and calculates microwave channel distortion parameters for baseband compensation in the digital domain; these parameters include multipath phase difference. The calculation of multipath phase difference is based on the geometric topology of the transmit and receive links; the system incorporates the transmit antenna height... Receiving antenna height and horizontal distance between transmission and reception Determine the coordinates of the sea surface mirror reflection point. .

[0038] The microprocessor calculates the horizontal component from the transmitter to the reflection point based on the principle of similar triangles. This establishes the coordinate mapping points along the transmission and reception connection; the microprocessor utilizes the transient geometric topological deformation of the wave reflector. Extract the coordinates of the corresponding sea surface mirror reflection point. Predicted elevation at the location .

[0039] The system calculates the lengths of the direct path and the reflected multipath separately; the direct path does not pass through the sea surface interface for reflection, and the microprocessor calculates the length of the direct path using the Euclidean distance formula. :

[0040] The reflected signal contacts the sea surface wave layer, and the microprocessor introduces a predicted elevation. Determine the length of the reflection multipath. :

[0041] Based on the length of the reflection multipath Length of the direct path The difference is that the control unit combines the microwave carrier wavelength. The multipath phase difference predicted at the receiver is derived. The multipath phase difference The mathematical expression is defined as follows:

[0042] In this embodiment, the microwave channel distortion parameters also include the cross-polarization depolarization crosstalk matrix. The calculation of the cross-polarization depolarization crosstalk matrix includes the extraction of the slope vector; the system calculates the transient slope normal vector at the predicted reflection point for the wave slope corresponding to the transient geometric topological deformation of the wave reflector. .

[0043] The microprocessor constructs this vector using the partial derivatives of the elevation function along the orthogonal spatial coordinate axes:

[0044] Obtain the transient slope normal vector Then, the control unit extracts the incident microwave wave vector sent by the transmitting array. The system calculates the incident microwave wave vector. With the transient inclined plane normal vector The inner product is used to obtain the depolarization rotation angle induced by geometric deflection. .

[0045] The inner product operation relationship is expressed as follows:

[0046] When a microwave signal is reflected on an inclined water surface, the original horizontal polarization component and vertical polarization component undergo energy coupling and polarization deflection; the system adjusts the depolarization rotation angle accordingly. Using the trigonometric function values, construct the transient cross-polarization-depolarization crosstalk matrix. .

[0047] The matrix The matrix structure for mapping the interference coefficients between orthogonally polarized channels is defined as follows:

[0048] The control unit will use the cross-polarization depolarization crosstalk matrix The data is stored in a register, which forms the basis of the mathematical model for subsequent dual-polarized receiver crosstalk cancellation.

[0049] In this embodiment, in addition to the polarization and phase parameters mentioned above, the microwave channel distortion parameters include a Doppler frequency shift component. The calculation of the Doppler frequency shift component relies on the characteristics of ocean wave dynamics; the microprocessor uses the hydrodynamic evolution results to extract the local vertical velocity component at the predicted reflection point. .

[0050] This local vertical velocity component is obtained based on the first partial derivative of the transient geometric topological deformation function of the wave reflector with respect to the time variable. Since the fluid particle trajectory is deflected under surface wind stress, the control unit divides the wave deformation into two regions: the windward and leeward sides, and extracts the local vertical velocity component from the windward side separately. and the local vertical velocity component on the leeward side This characterizes the asymmetry of the deformation rate; the control unit extracts the inherent microwave carrier frequency of the microwave transceiver's radio frequency oscillator. and the speed of light constant .

[0051] For any predicted reflection point, the control unit extracts its local vertical velocity component. Combined with microwave carrier frequency speed of light constant and the incident angle of microwaves on the local inclined plane. Calculate the Doppler frequency shift component generated by the multipath signal at this point. The Doppler frequency shift component The mathematical equation is set as follows:

[0052] After calculating the microwave channel distortion parameters in the digital domain, the system synchronously derives the physical layer spatial control parameters for beam pre-alignment configuration. The control unit extracts the ship attitude vectors for future moments from the previously output hydrodynamic model. The predicted future ship attitude vectors are then converted into attitude compensation angles. subscript Represents azimuth. Represents the pitch angle.

[0053] The microprocessor internally constructs a three-dimensional Euler angle rotation matrix from the geographic coordinate system to the antenna array coordinate system. The rotation matrix The elements are generated based on the sine and cosine values ​​of the roll, pitch, and yaw components at future times. The system extracts the preset line-of-sight spatial coordinates of the target communication node and uses a rotation matrix. Perform matrix multiplication on the preset view distance spatial coordinates.

[0054] After the coordinate space transformation is completed, the arithmetic unit extracts the geometric projections of the transformation result onto the horizontal and elevation axes of the antenna array. The microprocessor processes the geometric projection ratio based on the arctangent function, and then calculates the azimuth compensation components. pitch compensation component These two components combine to form the attitude compensation angle for physical layer RF beam pre-alignment, and together with microwave channel distortion parameters, they form the feedforward instruction set flowing to the execution hardware.

[0055] In this embodiment, after acquiring various feedforward instructions, the system performs joint feedforward pre-configuration of radio frequency and baseband in parallel; the pre-configuration process includes beam pre-alignment configuration, channel multipath phase compensation configuration, cross-polarization interference canceller coefficient feedforward preset, and constellation diagram dynamic pre-distortion configuration.

[0056] The control bus distributes the attitude compensation angle to the underlying mechanical control motherboard. The mechanical servo system starts the orientation motor based on the attitude compensation angle. An absolute photoelectric encoder is fixedly mounted on the shaft end of the orientation motor. The controller hardware interface reads the encoder pulse count in real time and converts it into the system's real-time actual mechanical pointing angle. .

[0057] The differential operator inside the microprocessor operates synchronously, calculating the difference between the attitude compensation angle corresponding to the preset lead time step and the actual mechanical pointing angle of the system in real time, generating a dynamic mechanical response residual. The beam controller receives the mechanical response residual and drives the distributed phase shifter network inside the RF phased array to perform weighted configuration. The RF phased array performs beam electrical deflection based on the dynamic mechanical response residual, relying on the non-inertial scanning characteristics of electromagnetic waves to compensate for the angular hysteresis during the physical start-up process of the motor, thereby maintaining the alignment of the main beam peak.

[0058] For the channel multipath phase compensation configuration, the system will derive the multipath phase difference predicted by the receiver. The feedforward is fed into the phase synchronization compensation module inside the baseband receiver. The digital signal processing unit in this module reads the built-in lookup table of Euler's formula and directly constructs the reverse phase rotation vector based on the multipath phase difference. The phase synchronization compensation module presets a reverse phase rotation vector before the physical distortion of the channel occurs. It performs a complex product operation between the baseband sampling sequence input to the receiver and the rotation vector to cancel the multipath phase distortion caused by the abrupt change in sea surface geometry.

[0059] Within the same processing pipeline for multipath phase compensation, the system synchronously performs cross-polarization interference canceller coefficient feedforward presets. In the baseband dual-polarization receiver, the matrix operation core extracts the cross-polarization depolarization crosstalk matrix cached in memory. The processor inverts the predicted cross-polarization depolarization crosstalk matrix to obtain the feedforward weight matrix of the cross-polarization interference canceller. .

[0060] The mathematical relationship of the feedforward weight matrix is ​​expressed as follows: The baseband controller directly injects the row and column components of the feedforward weight matrix as the initial tap coefficients of the adaptive finite-length unit impulse response equalizer into the hardware, thus replacing the default zero-value initialization state of the traditional equalizer. After injecting the initial tap coefficients, the baseband processor activates the minimum mean square error update algorithm and sets the step size factor parameter. The initial tap coefficients are fine-tuned in the time domain using the received baseband error signal to compensate for the theoretical residuals in the derivation model.

[0061] The baseband processor then performs a constellation diagram dynamic pre-distortion configuration; the system calculates the Doppler frequency shift components. Feedforward to a quadrature amplitude modulation (QAM) soft-decision demodulator. The storage area of ​​the QAM soft-decision demodulator stores a standard complex plane demodulation mesh; the microprocessor extracts the symbol period. Calculate the single-symbol phase rotation deviation angle caused by the Doppler effect. .

[0062] Regarding the first The center coordinates of a standard constellation grid The baseband microprocessor performs pre-distortion rotation calculations to generate the compensated geometric center coordinates. The baseband controller extracts the real and imaginary parts of this coordinate and uses them as the updated in-phase axis boundary threshold and orthogonal axis boundary threshold, respectively, thereby dynamically changing the geometric center coordinates of the decision boundaries in the demodulation grid. The soft-decision demodulator performs asymmetric soft-decision demodulation on the received symbols based on the offset decision boundaries to suppress inter-symbol interference caused by asymmetric wave motion; the system continuously demodulates and transmits the microwave high-speed data stream based on the above pre-configuration results.

[0063] In this embodiment, to support the above-mentioned marine microwave transmission method based on an automatic tracking mechanism, the present invention provides an electronic device; the electronic device, as the core computing hub for hydrodynamic prediction and parameter configuration, is deployed inside the control cabinet of the microwave communication node.

[0064] This electronic device integrates a processor, memory, and communication peripheral interfaces; the processor, memory, and communication peripheral interfaces establish a bidirectional data transmission link via the system's internal data bus. The processor contains a general-purpose central processing core, a field-programmable gate array, or a digital signal processing microchip; the memory is configured with random access memory space and non-volatile storage media.

[0065] The memory contains a sequence of computer program instructions; the processor reads and runs this sequence of instructions from the memory, performing the aforementioned hydrodynamic model calculations, channel distortion parameter mapping, and feedforward instruction issuance operations. The communication peripheral interface establishes hardwired connections to the inertial measurement unit, microwave radar, mechanical servo system, and baseband dual-polarization receiver, thereby enabling real-time acquisition of underlying sensor data and hardware-level injection of control parameters.

[0066] In this embodiment, the present invention simultaneously provides a computer-readable storage medium; the computer-readable storage medium internally contains continuous data clusters for recording a program instruction set for implementing the aforementioned high-speed microwave transmission method. The computer-readable storage medium includes a magnetic storage disk, a read-only optical disk, a solid-state drive, or a flash memory chip; after the system is powered on and reset, the motherboard boot program reads the instruction set and loads it into the memory operating space.

Claims

1. A marine microwave transmission method based on an automatic tracking mechanism, characterized in that, Includes the following steps: Obtain the ship's transient attitude vector at the current moment and the instantaneous two-dimensional elevation distribution function of the sea wave surface in the area covered by the transmission link; The ship's transient attitude vector and the instantaneous two-dimensional elevation distribution function of the wave surface are input into the ship wave coupled hydrodynamics model to predict the ship's attitude vector and the transient geometric topological deformation of the wave reflector at a future moment after a preset lead time step. Based on the predicted ship attitude vector at the future moment and the transient geometric topological deformation of the wave reflector, the attitude compensation angle for physical layer radio frequency beam pre-alignment is calculated, and the microwave channel distortion parameters for baseband compensation are mapped and calculated in the baseband digital domain. The microwave channel distortion parameters include the cross-polarization-depolarization crosstalk matrix; The process of calculating the cross-polarization depolarization crosstalk matrix includes: For the wave slope corresponding to the transient geometric topological deformation of the wave reflector, calculate and predict the transient slope normal vector at the reflection point; The depolarization rotation angle caused by geometric deflection is obtained by calculating the inner product of the incident microwave wave vector and the transient inclined plane normal vector. Based on the trigonometric function value of the depolarization rotation angle, construct the transient cross-polarization depolarization crosstalk matrix; The attitude compensation angle and the microwave channel distortion parameters are used as feedforward commands and are synchronously sent to the physical layer and baseband layer control unit before the arrival of the future time to perform joint feedforward pre-configuration of radio frequency and baseband, and the demodulation and transmission of microwave high-speed data stream are performed based on the pre-configuration results. The joint feedforward pre-configuration of RF and baseband includes feedforward pre-setting of cross-polarization interference canceller coefficients: In the baseband dual-polarization receiver, the predicted cross-polarization depolarization crosstalk matrix is ​​inverted to obtain the feedforward weight matrix of the cross-polarization interference canceller. The feedforward weight matrix is ​​directly injected as the initial tap coefficients of the adaptive equalizer.

2. The marine microwave transmission method based on an automatic tracking mechanism according to claim 1, characterized in that, The process of obtaining the ship's transient attitude vector at the current moment and the instantaneous two-dimensional elevation distribution function of the sea surface in the transmission link coverage area includes: The roll, pitch, and bow angles of the local vessel are collected using an inertial measurement unit as the vessel's transient attitude vector; Using data collected by microwave radar front-end scattering echo or optical sensors, the elevation data corresponding to the orthogonal spatial coordinates of the sea surface around the transmission link are extracted, and the instantaneous two-dimensional elevation distribution function of the sea wave surface is constructed.

3. The marine microwave transmission method based on an automatic tracking mechanism according to claim 1, characterized in that, The preset lead time step is greater than the sum of the mechanical servo delay and the baseband processing delay of the microwave transmission system. The ship wave coupled hydrodynamic model uses fluid kinematics equations to derive the time evolution of wave elevation, combines the surface velocity vector of wave particles and gradient operator to output the transient geometric topological deformation of the wave reflector, and synchronously outputs the ship attitude vector at the future moment based on rigid body kinematics and fluid force mapping.

4. The marine microwave transmission method based on an automatic tracking mechanism according to claim 1, characterized in that, The microwave channel distortion parameters include multipath phase difference, and the process of calculating the multipath phase difference includes: The coordinates of the sea surface mirror reflection point are determined by combining the height of the transmitting antenna, the height of the receiving antenna, and the horizontal distance between the transmitting and receiving antennas. The predicted elevation of the corresponding coordinates is extracted by utilizing the transient geometric topological deformation of the wave reflector, and the lengths of the direct path and the reflection multipath are calculated respectively. Based on the difference between the length of the reflected multipath and the length of the direct path, and in conjunction with the microwave carrier wavelength, the multipath phase difference predicted by the receiver is derived.

5. The marine microwave transmission method based on an automatic tracking mechanism according to claim 1, characterized in that, The microwave channel distortion parameters include a Doppler frequency shift component, and the process of calculating the Doppler frequency shift component includes: Extract the local vertical velocity component at the predicted reflection point to characterize the asymmetry of deformation rate between the windward and leeward sides of the wave. The Doppler frequency shift component generated by the multipath signal is calculated by combining the microwave carrier frequency, the speed of light, and the incident angle of the microwave on the local inclined plane.

6. The marine microwave transmission method based on an automatic tracking mechanism according to claim 1, characterized in that, The joint feedforward pre-configuration of RF and baseband includes beam pre-alignment configuration: The predicted ship attitude vector at the future moment is converted into the attitude compensation angle; While the mechanical servo system starts the orientation motor according to the attitude compensation angle, it calculates the difference between the attitude compensation angle and the actual mechanical pointing angle of the system in real time to obtain the dynamic mechanical response residual, and drives the radio frequency phased array to perform beam electrical deflection according to the dynamic mechanical response residual to maintain the main beam peak alignment.

7. The marine microwave transmission method based on an automatic tracking mechanism according to claim 4, characterized in that, The joint feedforward pre-configuration of RF and baseband includes channel multipath phase compensation configuration: The multipath phase difference predicted by the receiver is fed forward to the phase synchronization compensation module of the baseband receiver. Before the channel distortion occurs, a reverse phase rotation vector is preset to compensate for the multipath phase distortion caused by the abrupt change in sea surface geometry.

8. The marine microwave transmission method based on an automatic tracking mechanism according to claim 5, characterized in that, The joint feedforward pre-configuration of RF and baseband includes dynamic pre-distortion configuration of the constellation diagram: The calculated Doppler frequency shift component is fed forward to the quadrature amplitude modulation soft decision demodulator; The geometric center coordinates of the determination boundary in the demodulation grid are dynamically changed according to the offset of the Doppler frequency shift component, and asymmetric pre-distortion is performed to suppress inter-symbol interference caused by asymmetric wave motion.

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