In-field simulation system and method for polarized radar radio frequency guidance under rolling condition

Abstract

The application relates to an indoor field simulation system and method for polarized radar radio frequency guidance under rolling conditions, wherein the system comprises a radio frequency turntable, a radar and a target radio frequency signal simulation system of a variable polarization base placed in a microwave darkroom; the radar is fixed on the radio frequency turntable; the radio frequency turntable adjusts the radar posture according to input posture information, changes the direction of the radar receiving antenna to simulate the radar receiving posture under the rolling condition; the target radio frequency signal simulation system is placed on the opposite side of the radar, is used for simulating the target radio frequency signal, radiates to the microwave darkroom based on an array type three-element antenna, and is used for the radar guidance system to detect and track the simulated target; the simulated target radio frequency signal is a polarized target echo coupled with the radar posture, the polarization base direction of the polarized target echo is adjustable, and the polarized target echo is matched with the radar polarization receiving direction. The application guarantees correct simulation of the polarized target signal when the rolling angle changes, and realizes radio frequency simulation test verification of the radar system.

Description

Technical Field

[0001] This invention relates to the field of radio frequency simulation technology, and in particular to an indoor field simulation system and method for radio frequency guidance of polarized radar under roll conditions. Background Technology

[0002] The indoor radio frequency (RF) simulation system is used for hardware-in-the-loop (HIP) simulation of radar systems. Currently, most domestic RF simulation systems primarily use horizontally or vertically polarized electromagnetic signals radiated by the air-feed system, resulting in a simple signal form and relatively straightforward implementation. To better study the target detection, identification, and tracking technologies of the newly developed arbitrary polarization radar, it is necessary to simulate the target polarization scattering characteristics and target angular position tracking under arbitrary polarization in a laboratory environment, providing a hardware-in-the-loop simulation environment for the design and development of homing system polarization radars.

[0003] For radar RF simulations mounted on airborne and other moving platforms, when the radar roll angle changes drastically, the fixed polarization direction of the radiating antenna in existing RF simulation systems (i.e., fixed polarization base) leads to poor matching between the polarization radiation of the RF simulation system and the polarization reception of the radar, thus failing to accurately simulate the polarized target signal. Furthermore, when the radar operates in single-polarization mode, the radiating antenna used to simulate the RF target signal and the radar receiving antenna will form cross-polarization, resulting in a weakened target signal strength detected by the radar and causing unstable target tracking. Therefore, how to simulate the polarization characteristics of the RF signal coupled with the radar attitude in the RF simulation system, especially under large roll conditions, is a problem that urgently needs to be solved in RF simulation experiments and verification of radar systems. Summary of the Invention

[0004] Based on the above analysis, this invention aims to disclose an indoor field simulation system and method for polarization radar radio frequency guidance under roll conditions. It achieves simulation of the polarization characteristics of radio frequency signals coupled with radar attitude, solving the problem of radio frequency simulation and experimental verification of radar systems under roll conditions.

[0005] The present invention discloses an indoor field simulation system for polarization radar radio frequency guidance under roll conditions, including a radio frequency turntable, a radar, and a target radio frequency signal simulation system with variable polarization base placed in a microwave anechoic chamber;

[0006] The radar is fixed on the radio frequency turntable; the radio frequency turntable adjusts the radar attitude according to the input attitude information, changes the direction of the radar receiving antenna, and simulates the radar receiving attitude including roll conditions.

[0007] The variable polarization base target radio frequency signal simulation system is placed on the opposite side of the radar to simulate the target radio frequency signal. Based on the array-type triple antenna, it is radiated into the microwave anechoic chamber for the radar guidance system to detect and track the simulated target.

[0008] The simulated target radio frequency signal is a polarized target echo coupled with radar attitude, and its polarization base direction is adjustable so that the polarized target echo matches the radar polarization receiving direction.

[0009] Furthermore, the target radio frequency signal simulation system with variable polarization base includes a target simulation unit, a polarization matching unit, a precision controller, and an antenna feed system;

[0010] The target simulation unit is used to simulate the time-frequency characteristics of the radar target, and generate the horizontal polarization echo and vertical polarization echo of the target in real time; the polarization feature modulation of the horizontal polarization echo and vertical polarization echo of the target is performed by using the polarization scattering matrix of the target to obtain the polarization echo;

[0011] The polarization matching unit is used to construct a new polarization base based on the radar roll angle, adjust and match the polarization echo, and obtain a polarization combined echo that matches the radar polarization receiving direction.

[0012] The precision position controller is used for precise vertical and horizontal positioning control of the polarized combined echo;

[0013] The antenna system is used to radiate the polarized combined echo, which has been precisely controlled vertically and horizontally, into the microwave anechoic chamber space to form a simulated target echo signal.

[0014] Furthermore, the target simulation unit includes a radar target time-frequency characteristic simulation module and a polarization characteristic modulation module;

[0015] The radar target time-frequency characteristic simulation module is used to acquire the radar's transmitted waveform, operating timing sequence, target delay, and Doppler information; based on the radar waveform and the simulated target's delay and Doppler information, and according to the polarimetric radar's operating timing sequence, it performs radar target time-frequency characteristic simulation and generates the target's horizontal polarimetric echo S in real time. tr H and vertically polarized echo S tr V ;

[0016] The polarization feature modulation module is used to modulate the horizontal polarization echo S of the target according to the target's polarization scattering matrix. tr H and vertically polarized echo S tr V Polarization characteristic modulation is performed to obtain the polarization echo S. r H S r V ;

[0017]

[0018] Among them, S HH S is the complex scattering coefficient of the target when it is emitted and received in H polarization; HV S is the complex scattering coefficient of the target when it is emitted in H polarization and received in V polarization; VH S represents the complex scattering coefficient of the target when it is emitted in V-polarization and received in H-polarization; VV H represents the complex scattering coefficient of the target when it is emitting V-polarized and receiving V-polarized; H represents horizontal polarization and V represents vertical polarization.

[0019] Furthermore, the polarization matching unit includes a polarization matching module and a polarization combined echo generation module;

[0020] The polarization matching module is used to match the polarization echo S using a built-in polarization radiation and polarization reception matching model. r H S r V Orthogonal calculations, attenuation control, and phase compensation are performed to obtain horizontal and vertical polarization echoes that match the radar polarization receiving direction.

[0021] The polarization echo generation module performs power synthesis on horizontal and vertical polarization echoes to obtain a polarization echo.

[0022] Furthermore, the polarization radiation and polarization reception matching model is as follows:

[0023]

[0024] In the formula, S r H It is the matched horizontal polarization echo, S r V For the matched vertical polarization echo, and It is a set of polarization orthogonal unit vectors defined by the radar transmitting / receiving antenna; and S is a set of polarization orthogonal unit vectors defined by the dual-polarized antenna used for echo simulation; r H ⊥ The corresponding signal component of the horizontally polarized echo signal in the V channel of the target echo simulation, S r H || The corresponding signal component of the horizontally polarized echo signal in the H channel of the target echo simulation; S r V ⊥ The corresponding signal component of the vertically polarized echo signal in the V channel of the target echo simulation, S r V ||The corresponding signal component of the horizontally polarized echo signal in the H channel of the target echo simulation; S r H ⊥ S r V ⊥ S r H || and S r V || Determined based on radar roll angle.

[0025] Furthermore, S is determined based on the radar roll angle γ(t). r H ⊥ S r V ⊥ S r H || and S r V || for:

[0026]

[0027] In the formula, δ H It is echo S r H ⊥ Advanced S r H || Time phase angle; δ V It is echo S r V ⊥ Advanced S r V || Time phase angle;

[0028] in,

[0029] Furthermore, the polarization matching module includes four independent amplitude and phase control channels, each controlled by the radar roll angle γ(t), and composed of high-precision numerically controlled attenuators and numerically controlled phase shifters; the four independent amplitude and phase control channels are S... r H ⊥ Branch road, S r H || Branch road, S r V ⊥ Branch and S r V ||Branch circuit; control process is as follows:

[0030] When -π / 2 ≤ γ(t) < -π / 4, S r H ⊥ Branch power remains constant, S r H || The branch power attenuation is ΔP H Phase shift is 0; S r V ⊥ The branch power attenuation is ΔP V S r V || The branch power remains constant, and the phase shift is π.

[0031] When -π / 4 ≤ γ(t) < 0, S r H ⊥ The branch power attenuation is ΔP H S r H || Branch power remains constant, and phase shift is 0; S r V ⊥ Branch power remains constant, S r V || The branch power attenuation is ΔP V The phase shift is π;

[0032] When 0 ≤ γ(t) < π / 4, S r H ⊥ The branch power attenuation is ΔP H S r H || Branch power remains constant, and phase shift is π; S r V ⊥ Branch power remains constant, S r V || The branch power attenuation is ΔP V The phase shift is 0;

[0033] When π / 4 ≤ γ(t) < π / 2, S r H ⊥ Branch power remains constant, S r H || The branch power attenuation is ΔP HThe phase shift is π; S r V ⊥ The branch power attenuation is ΔP V S r V || The branch power remains constant and the phase shift is 0.

[0034] in,

[0035]

[0036] P(·) is the power attenuation control function.

[0037] Furthermore, the polarization combined echo generation module includes a first power combining module and a second power combining module;

[0038] The first power combining module is used to combine S r H ⊥ S r V ⊥ Two-in-one power combining is performed to obtain the V-channel vertical transmit-receive combined echo:

[0039] S r⊥ =S r H ⊥ +S r V ⊥ ;

[0040] The second power combining module is used to combine S r H || S r V || Two-in-one power combining is performed to obtain the horizontal transmit-receive combined echo of channel H:

[0041] S r|| =S r H || +S r V || .

[0042] Furthermore, the target radio frequency signal simulation system also includes a polarization scattering feature library; the polarization scattering feature library includes polarization scattering matrices corresponding to the relative angle of the radar target; when the current relative angle of the radar target is input, the polarization scattering feature library outputs the corresponding polarization scattering matrix to the polarization feature modulation module for the horizontal polarization echo S of the target. tr H and vertically polarized echo Str V Polarization feature modulation is performed.

[0043] This invention also discloses an interior field simulation method for polarized radar radio frequency guidance under roll conditions, comprising the following steps:

[0044] Step S1: Perform polarization target angle consistency calibration and phase alignment calibration of the target signal simulation system with variable polarization base; eliminate the amplitude and phase difference of the horizontal and vertical channels to ensure that the hardware electrical length of the horizontal and vertical distribution networks remains consistent.

[0045] Step S2: The radar attitude information calculated by the trajectory solution is sent to the radio frequency turntable to simulate the radar attitude. At the same time, the radar roll angle, time delay, Doppler information and radar target relative angle are sent to the target signal simulation system.

[0046] Step S3: The target signal simulation system receives modulation information, time delay, and Doppler information, performs radar target time-frequency characteristic simulation, and generates the target's horizontal and vertical polarization echoes in real time. Based on the radar target relative angle, the polarization scattering matrix is ​​retrieved to perform polarization feature modulation on the target's horizontal and vertical polarization echoes to obtain polarization echoes. The polarization echoes are then adjusted and matched based on the radar roll angle to obtain a combined polarization echo that matches the radar's polarization receiving direction. Through precise positioning control and the antenna feed system, the combined polarization echo signal, after vertical and horizontal precise positioning control, is radiated into the microwave anechoic chamber space.

[0047] Step S4: The polarimetric radar receives the synthesized polarimetric echo signal and performs corresponding signal processing to achieve target detection and tracking.

[0048] This invention can achieve one of the following beneficial effects:

[0049] This invention discloses an indoor field simulation system and method for polarization radar radio frequency guidance under roll conditions. It establishes a polarization radiation and polarization reception matching model based on the roll angle, overcoming the deficiency of fixed polarization direction of the radiating antenna in existing radio frequency simulation systems. It achieves adjustment of the polarization direction of the triplet radiating antenna, ensuring consistency with the orthogonal coordinate system of the transmitting / receiving antennas when the radar has a roll angle. This guarantees the matching between the simulated polarized target echo and the radar system's polarization reception, satisfying optimal matching reception of the target echo signal power for a large dynamic radar under indoor field conditions. It achieves accurate simulation of the polarized target signal when the roll angle changes, supporting radio frequency simulation experiments and verification of the radar guidance system under large roll conditions. Attached Figure Description

[0050] The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Throughout the drawings, the same reference numerals denote the same parts.

[0051] Figure 1 This is a block diagram illustrating the connection principle of the internal field simulation system for polarization radar radio frequency guidance under roll conditions in an embodiment of the present invention.

[0052] Figure 2 This is an example diagram of an orthogonal coordinate system for the polarization radiation and polarization reception matching model in an embodiment of the present invention;

[0053] Figure 3 This is a flowchart of the indoor field simulation method for polarized radar radio frequency guidance under roll conditions in an embodiment of the present invention.

[0054] Figure 4 This is a flowchart illustrating the target channel consistency calibration process in an embodiment of the present invention. Detailed Implementation

[0055] Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, which form part of this application and, together with the embodiments of the present invention, serve to illustrate the principles of the present invention.

[0056] Example 1

[0057] One embodiment of the present invention discloses an indoor field simulation system for polarization radar radio frequency guidance under roll conditions, such as... Figure 1 As shown, it includes a radio frequency turntable, radar, and a target radio frequency signal simulation system with variable polarization base placed in a microwave anechoic chamber;

[0058] The radar is fixed on the radio frequency turntable; the radio frequency turntable adjusts the radar attitude according to the input attitude information, changes the direction of the radar receiving antenna, and simulates the radar receiving attitude including roll conditions.

[0059] The variable polarization base target radio frequency signal simulation system is placed on the opposite side of the radar to simulate the target radio frequency signal. Based on the array-type triple antenna, it is radiated into the microwave anechoic chamber for the radar guidance system to detect and track the simulated target.

[0060] The simulated target radio frequency signal is a polarized target echo coupled with radar attitude, and its polarization base direction is adjustable so that the polarized target echo matches the radar polarization receiving direction.

[0061] Specifically, such as Figure 2 As shown, the target radio frequency signal simulation system with variable polarization base includes a target simulation unit, a polarization matching unit, a precision controller, and an antenna feed system;

[0062] The target simulation unit is used to simulate the time-frequency characteristics of the radar target, and generate the horizontal polarization echo and vertical polarization echo of the target in real time; the polarization feature modulation of the horizontal polarization echo and vertical polarization echo of the target is performed by using the polarization scattering matrix of the target to obtain the polarization echo;

[0063] The polarization matching unit is used to construct a new polarization base based on the radar roll angle, adjust and match the polarization echo, and obtain a polarization combined echo that matches the radar polarization receiving direction.

[0064] The precision position controller is used for precise vertical and horizontal positioning control of the polarized combined echo;

[0065] The antenna system is used to radiate the polarized combined echo, which has been precisely controlled vertically and horizontally, into the microwave anechoic chamber space to form a simulated target echo signal.

[0066] Specifically, the target simulation unit includes a radar target time-frequency characteristic simulation module and a polarization characteristic modulation module;

[0067] The radar target time-frequency characteristic simulation module is used to acquire the radar's transmitted waveform, operating timing, target time delay τ(t), and Doppler information f. d (t); based on radar waveform and the time delay τ(t) and Doppler information f of the simulated target. d (t), based on the operating sequence of the polarimetric radar, the time-frequency characteristics of the radar target are simulated, and the horizontal polarimetric echo S of the target is generated in real time. tr H and vertically polarized echo S tr V ;

[0068] In this embodiment, when performing radar target time-frequency characteristic simulation, existing radar target time-frequency characteristic simulation methods can be referenced. Using existing radar target simulators to perform radar target time-frequency characteristic simulation does not affect the scope of protection of this invention.

[0069] The polarization feature modulation module is used to modulate the horizontal polarization echo S of the target according to the target's polarization scattering matrix. tr H and vertically polarized echo S tr V Polarization characteristic modulation is performed to obtain the polarization echo S. r H S r V ;

[0070]

[0071] Among them, S HHS is the complex scattering coefficient of the target when it is emitted and received in H polarization; HV S is the complex scattering coefficient of the target when it is emitted in H polarization and received in V polarization; VH S represents the complex scattering coefficient of the target when it is emitted in V-polarization and received in H-polarization; VV H represents the complex scattering coefficient of the target when it is emitting V-polarized and receiving V-polarized; H represents horizontal polarization and V represents vertical polarization.

[0072] Specifically, the polarization matching unit includes a polarization matching module and a polarization combined echo generation module;

[0073] The polarization matching module is used to match the polarization echo S using a built-in polarization radiation and polarization reception matching model. r H S r V Orthogonal calculations, attenuation control, and phase compensation are performed to obtain horizontal and vertical polarization echoes that match the radar polarization receiving direction.

[0074] More specifically, the polarization radiation and polarization reception matching model is as follows:

[0075]

[0076] In the formula, S r H It is the matched horizontal polarization echo, S r V For the matched vertical polarization echo, and It is a set of polarization orthogonal unit vectors defined by the radar transmitting / receiving antenna; and S is a set of polarization orthogonal unit vectors defined by the dual-polarized antenna used for echo simulation; r H ⊥ The corresponding signal component of the horizontally polarized echo signal in the V channel of the target echo simulation, S r H || The corresponding signal component of the horizontally polarized echo signal in the H channel of the target echo simulation; S r V ⊥ The corresponding signal component of the vertically polarized echo signal in the V channel of the target echo simulation, S r V || The corresponding signal component of the horizontally polarized echo signal in the H channel of the target echo simulation; S r H ⊥ S r V⊥ S r H || and S r V || Determined based on radar roll angle.

[0077] like Figure 2 As shown, an example of an orthogonal coordinate system for the polarization radiation and polarization reception matching model is given.

[0078] More specifically, S is determined based on the radar roll angle γ(t). r H ⊥ S r V ⊥ S r H || and S r V || for:

[0079]

[0080] In the formula, δ H It is echo S r H ⊥ Advanced S r H || Time phase angle; δ V It is echo S r V ⊥ Advanced S r V || Time phase angle;

[0081] in,

[0082] Preferred, such as Figure 1 As shown, the polarization matching module includes four independent amplitude and phase control channels, each controlled by the radar roll angle γ(t), and composed of high-precision numerically controlled attenuators and numerically controlled phase shifters; amplitude and phase control is performed to achieve polarization echo S. r H S r V Orthogonal decomposition of echo signal amplitude, attenuation control, and phase compensation processing:

[0083] More specifically, the four independent amplitude and phase control channels are S r H ⊥ Branch road, S rH || Branch road, S r V ⊥ Branch and S r V || Branch circuit, through a power divider, converts S r H Assigned to S r H ⊥ Branch and S r H || Branch circuit, through a power divider, converts S r V Assigned to S r V ⊥ Branch and S r V || Branch; based on the angle value of radar roll angle γ(t), respectively for S r H ⊥ Branch road, S r H || Branch road, S r V ⊥ Branch and S r V || The amplitude and phase of the branch circuit are controlled; the specific control process is as follows:

[0084] ΔP H =P(S) r H ⊥ )-P(S r H || )=20lg(|sinγ(t)| / |cosγ(t)|)=20lg(|tan(γ(t))|)

[0085] ΔP V =P(S) r V ⊥ )-P(S r V || )=20lg(|cosγ(t)| / |sinγ(t)|)=20lg(|cot(γ(t))|)

[0086] When -π / 2≤γ(t<-π / 4, S r H ⊥Branch power remains constant, S r H || The branch power attenuation is ΔP H Phase shift is 0; S r V ⊥ The branch power attenuation is ΔP V S r V || The branch power remains constant, and the phase shift is π.

[0087] When -π / 4 ≤ γ(t) < 0, S r H ⊥ The branch power attenuation is ΔP H S r H || Branch power remains constant, and phase shift is 0; S r V ⊥ Branch power remains constant, S r V || The branch power attenuation is ΔP V The phase shift is π;

[0088] When 0 ≤ γ(t) < π / 4, S r H ⊥ The branch power attenuation is ΔP H S r H || Branch power remains constant, and phase shift is π; S r V ⊥ Branch power remains constant, S r V || The branch power attenuation is ΔP V The phase shift is 0;

[0089] When π / 4 ≤ γ(t) < π / 2, S r H ⊥ Branch power remains constant, S r H || The branch power attenuation is ΔP H The phase shift is π; S r V ⊥ The branch power attenuation is ΔP V S r V|| The branch power remains constant and the phase shift is 0.

[0090] Specifically, the polarization echo generation module includes a first power combining module and a second power combining module;

[0091] The first power combining module is used to combine S r H ⊥ S r V ⊥ Two-in-one power combining is performed to obtain the V-channel vertical transmit-receive combined echo:

[0092] S r⊥ =S r H ⊥ +S r V ⊥ ;

[0093] The second power combining module is used to combine S r H || S r V || Two-in-one power combining is performed to obtain the horizontal transmit-receive combined echo of channel H:

[0094] S r|| =S r H || +S r V || .

[0095] Specifically, the precision positioning controller is controlled by the relative angle of the radar target to perform vertical and horizontal precision positioning control on the vertical and horizontal transmitted combined echoes;

[0096] Specifically, the antenna feed system is an array-type antenna feed system, which simulates the spatial angular position of the target signal through a three-element array with continuously changing angles. The spatial angular position of the target signal simulated by the target echo simulation method in this embodiment is consistent with the roll angle of the radar antenna feed system, ensuring the correct simulation of the polarized target signal when the roll angle changes, and supporting the radio frequency simulation test verification of the radar guidance system under large roll conditions.

[0097] In a preferred embodiment, the target signal simulation system further includes a polarization scattering feature library; the polarization scattering feature library includes polarization scattering matrices corresponding to the relative angle of the radar target; when the current relative angle of the radar target is input, the polarization scattering feature library outputs the corresponding polarization scattering matrix to the polarization feature modulation module for the horizontal polarization echo S of the target.tr H and vertically polarized echo S tr V Polarization feature modulation is performed.

[0098] The origin of the target's coordinate system is its centroid, and the three axes can be determined as needed, using a coordinate system with the northeast-sky axis as the three axes. The relative angles of the radar target include the radar yaw angle and the radar elevation angle.

[0099] The polarization scattering feature library can be obtained through field measurement, compact field testing, or electromagnetic calculation simulation.

[0100] In a more specific embodiment, the indoor simulation system also includes a radio frequency simulation control system. The radio frequency simulation control system provides radar target relative angle, target time delay and Doppler information to the radar target simulator of the target radio frequency signal simulation system according to the simulation requirements; provides radar roll angle to the polarization matching unit; and provides radar target relative angle to the precision controller.

[0101] In a more specific embodiment, the indoor simulation system also includes a radar control computer connected to the radar, used to control the radar's operating status information, including radar modulation information.

[0102] In a more specific scheme, a simulation computing system is also included, which is connected to the radar, radio frequency turntable and radio frequency simulation control system respectively, to generate simulation-related data and send them to the radar, radio frequency turntable and radio frequency simulation control system respectively for radio frequency simulation test verification of radar guidance system.

[0103] In summary, the solution of this invention establishes a polarization radiation and polarization reception matching model based on roll angle, which overcomes the deficiency of fixed polarization direction of radiating antenna in existing RF simulation systems. It realizes the adjustment of polarization direction of the triplet radiating antenna, making it consistent with the orthogonal coordinate system of the transmitting / receiving antenna polarization when the radar has a roll angle. This ensures the matching between the simulated polarized target echo and the radar system polarization reception, and satisfies the optimal matching reception of target echo signal power by large dynamic radar under indoor conditions. It also realizes the correct simulation of polarized target signal when the roll angle changes, supporting the RF simulation test verification of radar guidance system under large roll conditions.

[0104] Example 2

[0105] This embodiment discloses an interior field simulation method for polarized radar radio frequency guidance under roll conditions, such as... Figure 3 As shown, the following steps are:

[0106] Step S1: Perform polarization target angle consistency calibration and phase alignment calibration of the target signal simulation system with variable polarization base; eliminate the amplitude and phase difference of the horizontal and vertical channels to ensure that the hardware electrical length of the horizontal and vertical distribution networks remains consistent.

[0107] Step S2: The radar attitude information calculated by the trajectory solution is sent to the radio frequency turntable to simulate the radar attitude. At the same time, the radar roll angle, time delay, Doppler information and radar target relative angle are sent to the target signal simulation system.

[0108] Step S3: The target signal simulation system receives modulation information, time delay, and Doppler information, performs radar target time-frequency characteristic simulation, and generates the target's horizontal and vertical polarization echoes in real time. Based on the radar target relative angle, the polarization scattering matrix is ​​retrieved to perform polarization feature modulation on the target's horizontal and vertical polarization echoes to obtain polarization echoes. The polarization echoes are then adjusted and matched based on the radar roll angle to obtain a combined polarization echo that matches the radar's polarization receiving direction. Through precise positioning control and the antenna feed system, the combined polarization echo signal, after vertical and horizontal precise positioning control, is radiated into the microwave anechoic chamber space.

[0109] Step S4: The polarimetric radar receives the synthesized polarimetric echo signal and performs corresponding signal processing to achieve target detection and tracking.

[0110] Specifically, in step S1, the process of eliminating the amplitude and phase difference between the horizontal and vertical channels includes:

[0111] 1) Channel calibration;

[0112] First, measure the electrical length and phase relationship of each antenna element and its feeding system in the horizontal channel to generate a path table; the path table includes the amplitude and phase information of each antenna horn channel; then perform in-channel calibration based on the path table.

[0113] 2) Attenuator calibration;

[0114] Three attenuation tables were obtained by testing attenuators A, B, and C in the center triplet of the horizontal channel array; the attenuation tables include the correspondence between attenuation codes and attenuation amounts.

[0115] 3) Phase shifter calibration;

[0116] Three attenuation tables were obtained by testing phase shifters A, B, and C in the center triplet of the horizontal channel array; the attenuation tables include the correspondence between phase shift codes and phase shift amounts.

[0117] 4) Repeat steps 1 to 3) to eliminate the amplitude and phase difference of the vertical channel.

[0118] 5) Phase difference compensation between H and V channels;

[0119] The phase difference between the H and V channels is measured using a vector network analyzer, and then compensation is performed in the fine control of the H channel to eliminate the phase difference between the channels.

[0120] like Figure 4 As shown, a specific target channel consistency calibration workflow is presented.

[0121] Specifically, step S3 includes:

[0122] 1) Obtain the radar-target relative angle in the radar-target body coordinate system;

[0123] 2) Obtain the target's polarization scattering matrix based on the relative angle of the radar target;

[0124] 3) Simulate the time-frequency characteristics of radar targets and generate horizontal and vertical polarization echoes of the targets in real time; use the polarization scattering matrix of the targets to perform polarization feature modulation on the horizontal and vertical polarization echoes of the targets to obtain polarization echoes;

[0125] 4) Adjust and match the polarization echo based on the radar roll angle to obtain a combined polarization echo that matches the radar polarization receiving direction.

[0126] 5) The polarized echo is radiated into the microwave anechoic chamber space through vertical and horizontal precision control and the antenna feed system to form a simulated target echo signal.

[0127] The specific technical details and beneficial effects included in this embodiment are the same as those in the previous embodiment. Please refer to the content of the previous embodiment, and they will not be repeated here.

[0128] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A system for simulating in-field polarized radar RF guidance in rolling conditions, characterized by, The target radio frequency signal simulation system comprises a radio frequency turntable, a radar and a variable polarization base placed in a microwave anechoic chamber; The radar is fixed on the radio frequency turntable; the radio frequency turntable adjusts the radar attitude according to the input attitude information, changes the direction of the radar receiving antenna, and simulates the radar receiving attitude including the roll condition; The target radio frequency signal simulation system with a variable polarization base is placed on the opposite side of the radar, used for simulating the target radio frequency signal, radiated to the microwave anechoic chamber based on the array type triple antenna, for the radar guidance system to detect and track the simulated target; The simulated target radio frequency signal is a polarized target echo coupled with the radar attitude, and the polarization base direction is adjustable, so that the polarized target echo matches the radar polarization receiving direction; The target radio frequency signal simulation system with a variable polarization base comprises a target simulation unit, a polarization matching unit, a fine position controller and a feed system; The target simulation unit is used for simulating the target time-frequency characteristics of the radar, and generates the horizontal polarization echo and the vertical polarization echo of the target in real time; the polarization scattering matrix of the target is used to modulate the polarization characteristics of the horizontal polarization echo and the vertical polarization echo of the target, to obtain the polarization echo; The polarization matching unit is used for constructing a new polarization base based on the roll angle of the radar, adjusting and matching the polarization echo, to obtain the polarization combined echo matching the radar polarization receiving direction; The fine position controller is used for controlling the vertical and horizontal fine positions of the polarization combined echo; The feed system is used for radiating the polarization combined echo subjected to the vertical and horizontal fine position control to the microwave anechoic chamber space, to form the simulated target echo signal.

2. The polarization radar radio frequency guidance indoor simulation system according to claim 1, wherein The target simulation unit comprises a radar target time-frequency characteristic simulation module and a polarization characteristic modulation module; The radar target time-frequency characteristic simulation module is used to acquire the radar's transmitted waveform, operating sequence, target delay, and Doppler information; based on the radar waveform and the simulated target's delay and Doppler information, and according to the polarimetric radar's operating sequence, it performs radar target time-frequency characteristic simulation and generates the target's horizontal polarimetric echo in real time. and vertically polarized echo ; The polarization characteristic modulation module; Processing polarimetric radar data to obtain polarimetric signatures and to classify targets by polarimetric feature modulation ;​ ； wherein, is the complex scattering coefficient of the target when transmitting H polarization and receiving H polarization; is the complex scattering coefficient of the target when transmitting H polarization and receiving V polarization; is the complex scattering coefficient of the target when transmitting V polarization and receiving H polarization; is the complex scattering coefficient of the target when transmitting V polarization and receiving V polarization; H stands for horizontal polarization and V stands for vertical polarization.

3. The polarized radar RF guidance in-field simulation system of claim 1, wherein, The polarization matching unit comprises a polarization matching module and a polarization combined echo generation module; The polarization matching module is configured to utilize a built-in polarization radiation and polarization receiving matching model to match the polarization echo 、 Perform orthogonal solution, attenuation control and phase compensation to obtain horizontal and vertical polarization echoes matched with the radar polarization receiving direction. The polarization combined echo generation module performs power synthesis on the horizontal and vertical polarization echoes to obtain the polarization combined echo.

4. The polarization radar radio frequency guidance indoor simulation system according to claim 3, wherein The polarization radiation and polarization receiving matching model is: ； wherein, is the matched horizontal polarization echo, is the matched vertical polarization echo, and is a set of polarization orthogonal unit vectors defined by the radar transmit / receive antenna; and is a set of polarization orthogonal unit vectors defined by the dual-polarized antenna that performs the echo simulation; is the signal component of the horizontal polarization echo signal in the V channel of the target echo simulation, is the signal component of the horizontal polarization echo signal in the H channel of the target echo simulation; is the signal component of the vertical polarization echo signal in the V channel of the target echo simulation, is the signal component of the vertical polarization echo signal in the H channel of the target echo simulation; , , and is determined according to the radar roll angle.

5. The polarization radar radio frequency guidance indoor simulation system according to claim 4, wherein According to the radar roll angle determined , , and are: ； wherein is the echo is the time phase angle leading is the echo is the time phase angle is the time phase angle wherein .

6. The polarization radar radio frequency guidance indoor simulation system according to claim 5, wherein The polarization matching module includes four independent, respectively by radar roll angle Controlled by high-precision numerical control attenuator and numerical control phase shifter, amplitude and phase control channel Four independent amplitude and phase control channels are respectively Branch, Branch, Branch and Branch; the control process is: When the branch power is kept unchanged, the branch power is kept unchanged, the branch power decay amount is , and the phase shift amount is 0; the branch power decay amount is , the branch power is kept unchanged, and the phase shift amount is ; When , The branch power attenuation amount is , The branch power remains unchanged, and the phase shift amount is 0. The branch power remains unchanged, The branch power attenuation amount is , and the phase shift amount is ; When , the branch power decay amount is , the branch power remains unchanged, and the phase shift amount is ; the branch power remains unchanged, the branch power decay amount is , and the phase shift amount is 0; When , the branch power remains unchanged, the branch power decay amount is , and the phase shift amount is ; the branch power decay amount is , the branch power remains unchanged, and the phase shift amount is 0; wherein ； is a power decay control function.

7. The polarization radar radio frequency guidance indoor simulation system according to claim 6, wherein The polarization combined echo generation module comprises a first power synthesis module and a second power synthesis module; The first power synthesis module is configured to combine The two-in-one power synthesis is performed to obtain a V-channel vertically transmitting and receiving echo ； The second power synthesis module is configured to combine performing two-in-one power synthesis to obtain a horizontal transmission echo of the H channel 。 8. The polarized radar RF guidance in-field simulation system of claim 1, wherein, The target radio frequency signal simulation system further comprises a polarization scattering characteristic library; the polarization scattering characteristic library comprises a polarization scattering matrix corresponding to a relative angle of a radar target; when a current relative angle of a radar target is input, the polarization scattering characteristic library outputs a corresponding polarization scattering matrix to the polarization characteristic modulation module to perform polarization characteristic modulation on horizontal polarization echo and vertical polarization echo of the target.

9. An in-field simulation method for an in-field simulation system using the polarized radar radio frequency guidance according to any one of claims 1-8, characterized in that, The method comprises the following steps: Step S1, polarization target angle consistency calibration and phase alignment calibration of the target signal simulation system with a variable polarization base are performed; the amplitude and phase differences of the horizontal and vertical channels are eliminated, and the hardware electrical lengths of the horizontal and vertical distribution networks are ensured to be consistent; Step S2, the calculated radar attitude information is sent to the radio frequency turntable for simulating the radar attitude, and the radar roll angle, time delay, Doppler information and radar target relative angle are sent to the target signal simulation system; Step S3, the target signal simulation system receives the modulation information, time delay and Doppler information, performs target time-frequency feature simulation of the radar, and generates the horizontal polarization echo and the vertical polarization echo of the target in real time; the horizontal polarization echo and the vertical polarization echo of the target are modulated according to the radar target relative angle to obtain the polarization echo; and the polarization echo is adjusted and matched based on the roll angle of the radar to obtain the polarization combined echo matched with the polarization receiving direction of the radar; through the fine position control and the antenna feed system, the polarization combined echo signal subjected to vertical and horizontal fine position control is radiated to the microwave darkroom space; Step S4, the polarization radar receives the combined polarization echo signal, and performs corresponding signal processing to realize detection and tracking of the target.

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