Communication-in-motion antenna inertial navigation delay compensation system and method

Abstract

The invention relates to a communication-in-moving antenna inertial navigation delay compensation system and method. According to the system and method, a first navigation module is used for measuring the attitude, speed and position of a carrier in real time; the second navigation module is used for directly measuring the angular velocity and acceleration of the satellite communication terminal; the time delay module calculates a time delay parameter of the first navigation module, and then estimates the input time delay of the first navigation module when the carrier has obvious attitude angle deflection by establishing a combined navigation state space model containing a time delay error of the first navigation module; and meanwhile, delay compensation is carried out when the information of the first navigation module is used as combined navigation observation information, so that the attitude estimation precision is improved, and the method has the advantages of simplicity in operation and adaptability to random delay of the first navigation module.

Description

Technical Field

[0001] The present application relates to the field of satellite communications, and in particular to a system and method for compensating inertial navigation delay of a moving communications antenna. Background Art

[0002] With the development of communication technology, traditional satellite communication technology can no longer meet the demand. The emergence of communication solutions based on two-dimensional active phased array antennas and high-throughput satellites has solved business needs in more scenarios. Two-dimensional active phased array antenna products are gradually becoming popular due to their small size, light weight, easy to carry, and high performance, and have become one of the options for satellite communication solutions in the aviation field.

[0003] Due to its small size and high structural strength, the phased array antenna can be installed on the terminal without changing the original shape of the aircraft. Due to the lack of heading input, the existing ground satellite communication terminal needs to obtain the heading through blind scanning alignment before the next high-precision tracking process can be carried out. The carrier of the airborne satellite communication terminal has high-precision navigation information. In order to shorten the alignment time and improve the alignment accuracy, the airborne terminal antenna usually uses the airborne inertial navigation data as the initial heading value or measurement information of the satellite communication terminal sub-inertial navigation, and uses the transfer alignment method to converge to obtain the misalignment angle, velocity error and installation error angle.

[0004] The existing alignment method of airborne satellite communication terminals can estimate the installation error of the airborne antenna relative to the main inertial navigation on the carrier, and make real-time compensation to correct the antenna sub-inertial navigation attitude misalignment angle and velocity error. However, since the main inertial navigation information is often transmitted to the integrated navigation computer at a low frequency and there is a certain time lag in the information, the existing alignment method does not estimate and compensate for the main inertial navigation information delay, which leads to a time lag in attitude update in actual mobile communication applications, further making the beam pointing center unable to align with the satellite, reducing the communication quality and stability of the satellite communication link. In particular, when the carrier has a large-angle attitude deflection or obvious acceleration and deceleration movement, the delay will have a greater impact on the phased array beam pointing. Summary of the invention

[0005] In order to overcome the problems existing in the related art, the present application provides a moving antenna inertial navigation delay compensation system and method. The system establishes a combined navigation state space model including delay errors, estimates the main inertial navigation input delay when the carrier undergoes a significant attitude angle deflection, and performs delay compensation when the main inertial navigation information is used as combined navigation observation information to improve the attitude estimation accuracy. The system has the advantages of simple operation and adaptability to random delays of the main inertial navigation.

[0006] On the one hand, the present application provides an inertial navigation delay compensation system for a satellite communication antenna in motion, which includes: a first navigation module, installed on a carrier, and used to measure the carrier's attitude, speed and position in real time; a second navigation module, arranged on the antenna of a satellite communication terminal of the carrier, and used to directly measure the angular velocity and acceleration of the satellite communication terminal; a delay module, used to obtain the delay parameter of the first navigation module based on the time when the information of the first navigation module is detected to be transmitted to the calculation module and the time when the information of the second navigation module is detected to be transmitted to the calculation module; a calculation module, used to calculate the misalignment angle and speed error of the second navigation module based on the delay parameters of the first navigation module; a construction module, used to construct a state equation based on the misalignment angle of the second navigation module, the speed error of the second navigation module and the delay parameter as state quantities; an alignment module, used to estimate the state quantity of the second navigation module using a Kalman filter based on the state equation and correct the system error by a feedback correction method.

[0007] Preferably, the satellite communication terminal is fixed on a platform of the carrier and is located above the roll axis of the carrier, and the installation plane of the first navigation module on the surface of the carrier is the same plane as the installation plane of the satellite communication antenna on the surface of the carrier.

[0008] Preferably, an installation plane of the second navigation module is parallel to a traveling direction of the carrier, and is parallel to an installation plane of the first navigation module.

[0009] Preferably, the first navigation module comprises a first inertial sensor and a first GNSS position sensor, wherein the first inertial sensor is installed on three axes of the carrier coordinate system and is used to measure the angular velocity of the carrier attitude rotation and the component values ​​of the motion acceleration on the three axes.

[0010] Preferably, when the carrier rotates, the time for the measurement information of the first navigation module to be transmitted to the calculation module is T MINS The time for the measurement information of the second navigation module to be transmitted to the calculation module is T SINS The delay parameter of the first navigation module obtained by the delay module is δt=T SINS -T SINS , where the misalignment angle error of the second navigation module is The velocity error of the second navigation module is

[0011] Preferably, the construction module obtains the misalignment angle φ of the second navigation module n , velocity error δv n , gyro zero position ε b , plus zero position The installation error system state μ, and the delay parameter of the first navigation module is δt, and the construction state equation is obtained. The state equation is:

[0012]

[0013]

[0014]

[0015] in is the projection of the carrier's navigation system's angular velocity of rotation relative to the earth on the carrier's navigation system;

[0016] The Euler angle rotation matrix from the coordinate system formed by the gyroscope sensitive axis of the second navigation module to the n-system;

[0017] f n is the overload acceleration (specific force) of the navigation system of the carrier;

[0018] The gyro angular velocity measurement white noise of the second navigation module;

[0019] is the accelerometer specific force measurement white noise of the second navigation module;

[0020] The Euler angle rotation matrix from the coordinate system formed by the gyroscope sensitive axis of the first navigation module to the n-system;

[0021] is the attitude noise of the first navigation module;

[0022] V v is the speed noise.

[0023] On the other hand, the present application provides a method for compensating delay of an inertial navigation antenna in motion, which includes: collecting angular velocity and acceleration data of a first navigation module through a calculation module, and recording the time of collecting the data; collecting angular velocity and acceleration of a second navigation module through the calculation module, and recording the time of collecting the data; controlling a carrier to perform pitch, roll, and acceleration actions, and again collecting the time when information of the first navigation module is transmitted to the calculation module and the time when information of the second navigation module is transmitted to the calculation module, and obtaining the delay parameter of the first navigation module; constructing an observation model of the carrier according to the obtained delay parameter; using a Kalman filter as a transfer alignment filter according to the observation model to establish a system state equation; estimating the installation error delay obtained by the Kalman filter estimation, and correcting the error of the inertial navigation delay of the inertial navigation antenna in motion according to the delay estimate by using a feedback correction method.

[0024] Preferably, the construction of the observation model of the carrier according to the obtained delay parameter further comprises: controlling the carrier to rotate, collecting the measurement information of the first navigation module and transmitting it to the calculation module for a time T MINSThe time for collecting the measurement information of the second navigation module and transmitting it to the calculation module is T SINS , the delay parameter is δt=T MINS -T SINS ; The misalignment angle observation model of the second navigation module is calculated by a calculation module, and the misalignment angle observation model is The speed error observation model of the second navigation module is obtained by calculating the calculation module. The speed error observation model is:

[0025] Preferably, according to the observation model, using a Kalman filter as a transfer alignment filter, establishing the system state equation further comprises: using a building module to construct a state equation according to the misalignment angle of the second navigation module, the speed error and the delay parameter of the second navigation module as state quantities:

[0026]

[0027]

[0028]

[0029] in is the projection of the carrier's navigation system's angular velocity of rotation relative to the earth on the carrier's navigation system; The Euler angle rotation matrix from the coordinate system formed by the gyroscope sensitive axis of the second navigation module to the n-system;

[0030] f n is the navigation system overload acceleration (specific force) of the carrier;

[0031] The gyro angular velocity measurement white noise of the second navigation module;

[0032] is the accelerometer specific force measurement white noise of the second navigation module;

[0033] The Euler angle rotation matrix from the coordinate system formed by the gyroscope sensitive axis of the first navigation module to the n-system; is the attitude noise of the first navigation module;

[0034] V v is the speed noise.

[0035] Preferably, estimating the installation error delay obtained by Kalman filtering estimation, and correcting the error of the inertial navigation delay of the moving antenna using a feedback correction method according to the delay estimation further includes: according to the error estimation state equation, the estimated state quantity is:

[0036]

[0037] Where K f is the feedback factor, X f The feedback correction is used to correct the system navigation parameters. The residual error is used for subsequent filter updates. f ≠I is called partial feedback. f

[0038] When =I, it is called complete feedback.

[0039] The technical solution provided by the present application may include the following beneficial effects: by designing a first navigation module, a second navigation module, a delay module, a calculation module, a construction module and an alignment module, and then by establishing a combined navigation state space model including a delay error, the input delay of the first navigation module is estimated when a significant attitude angle deflection occurs in the carrier, and delay compensation is performed when the information of the first navigation module is used as combined navigation observation information, so as to improve the attitude estimation accuracy of the carrier. The solution has the advantages of simple operation and the function of adapting to the random delay of the main inertial navigation.

[0040] It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] The above and other objects, features and advantages of the present application will become more apparent through a more detailed description of exemplary embodiments of the present application in conjunction with the accompanying drawings, wherein the same reference numerals generally represent the same components in the exemplary embodiments of the present application.

[0042] Figure 1 is a structural diagram of an inertial navigation delay compensation system for a moving antenna shown in an embodiment of the present application;

[0043] Figure 2 is a schematic diagram of the installation of a satellite communication terminal shown in an embodiment of the present application;

[0044] Figure 3 is a flow chart of a method for compensating inertial navigation delay of a moving antenna shown in an embodiment of the present application;

[0045] Figure 4 is another flow chart of a method for compensating inertial navigation delay of a moving antenna shown in an embodiment of the present application;

[0046] Figure 5 It is a time-delay schematic diagram of the first navigation module shown in an embodiment of the present application. DETAILED DESCRIPTION

[0047] The preferred embodiments of the present application will be described in more detail below with reference to the accompanying drawings. Although the preferred embodiments of the present application are shown in the accompanying drawings, it should be understood that the present application can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided to make the present application more thorough and complete, and to fully convey the scope of the present application to those skilled in the art.

[0048] The terms used in this application are for the purpose of describing specific embodiments only and are not intended to limit this application. The singular forms of "a", "said" and "the" used in this application and the appended claims are also intended to include plural forms unless the context clearly indicates other meanings. It should also be understood that the term "and / or" used herein refers to and includes any or all possible combinations of one or more associated listed items.

[0049] It should be understood that although the terms "first", "second", "third", etc. may be used in this application to describe various information, this information should not be limited to these terms. These terms are only used to distinguish the same type of information from each other. For example, without departing from the scope of this application, the first information may also be referred to as the second information, and similarly, the second information may also be referred to as the first information. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined.

[0050] The technical solution of the embodiments of the present application is described in detail below with reference to the accompanying drawings.

[0051] Figure 1 It is a structural diagram of an inertial navigation delay compensation system for a moving antenna shown in one embodiment of the present application. Figure 2 It is a schematic diagram of the installation of a satellite communication terminal shown in an embodiment of the present application. Figure 5 It is a time-delay schematic diagram of the first navigation module shown in an embodiment of the present application.

[0052] See also Figure 1 , Figure 2 as well as Figure 5 A moving antenna inertial navigation delay compensation system includes: a first navigation module, a second navigation module, a delay module, a calculation module, a construction module and an alignment module.

[0053] The first navigation module is installed on a carrier, and is used to measure the attitude, speed and position of the carrier in real time.

[0054] In one embodiment, the first navigation module is a main inertial navigation MINS, which is installed inside the carrier and has a high-precision inertial navigation function. It can provide heading information for the satellite communication terminal antenna and realize the self-alignment function. The carrier of this system is a fixed-wing aircraft. The main inertial navigation is fixedly connected to the body of the fixed-wing aircraft and can perform pitch and roll movements with the body. The speed and position information measured by the main inertial navigation is used as the initial value or measurement information of the sub-inertial navigation after the lever arm compensation and delay compensation of the fixed-wing aircraft.

[0055] In one embodiment, the first navigation module includes a first inertial sensor and a first GNSS position sensor, the first inertial sensor is installed on the three axes of the carrier coordinate system, and is used to measure the angular velocity of the carrier's attitude rotation and the component values ​​of the motion acceleration on the three axes. That is, the main inertial navigation used includes the first inertial sensor and the first GNSS position sensor, the first inertial sensor also includes three gyroscopes and three accelerometers, the three gyroscopes are respectively installed on the three axes of the carrier coordinate system for measuring and outputting the component values ​​of the angular velocity of the carrier's attitude rotation on the three axes, and the three accelerometers are also respectively installed on the three axes of the carrier coordinate system for measuring and outputting the component values ​​of the carrier's motion acceleration on the three axes. The first GNSS position sensor is used to measure and output the geographic location of the carrier.

[0056] The second navigation module is arranged on the antenna of the satellite communication terminal of the carrier, and the second navigation module is used to directly measure the angular velocity and acceleration of the satellite communication terminal.

[0057] In one embodiment, the second navigation module is a low-precision inertial navigation installed in the antenna of the satellite communication terminal, also known as a sub-inertial navigation SINS. The sub-inertial navigation often does not have a heading self-alignment function and requires the main inertial navigation to provide heading information. That is, the second navigation module does not have a heading self-alignment function and requires the first navigation module to provide heading information to the second navigation module. The antenna is a moving communication antenna.

[0058] In one embodiment, the second navigation module includes a second inertial sensor and a second GNSS position sensor, the second inertial sensor is installed on the three axes of the carrier coordinate system, and is used to measure the angular velocity of the carrier's attitude rotation and the component values ​​of the motion acceleration on the three axes. That is, the sub-inertial navigation used includes a second inertial sensor and a second GNSS position sensor, the second inertial sensor also includes three gyroscopes and three accelerometers, the three gyroscopes are respectively installed on the three axes of the carrier coordinate system for measuring and outputting the component values ​​of the angular velocity of the carrier's attitude rotation on the three axes, and the three accelerometers are also respectively installed on the three axes of the carrier coordinate system for measuring and outputting the component values ​​of the carrier's motion acceleration on the three axes. The second GNSS position sensor is used to measure and output the geographic location of the carrier.

[0059] In one embodiment, the satellite communication terminal is fixed on the platform of the carrier and is located above the roll axis of the carrier, and the installation plane of the first navigation module on the surface of the carrier is the same plane as the installation plane of the moving communication antenna on the surface of the carrier. The installation plane of the second navigation module is parallel to the direction of travel of the carrier and parallel to the installation plane of the first navigation module. That is, because the sub-inertial navigation often does not have the heading self-alignment function, the sub-inertial navigation used needs to be installed in parallel with the direction of travel of the fixed-wing aircraft body. When the sub-inertial navigation and the fixed-wing aircraft body are not installed in parallel, it is necessary to perform coordinate conversion on the measurement data obtained by the sub-inertial navigation. If there is a small angle installation error between the sub-inertial navigation and the fixed-wing aircraft body during installation, the installation error can also be estimated during the transmission alignment process of delay estimation, and fed back to the strapdown inertial navigation for calculation and compensation. The carrier of this system is a fixed-wing aircraft, and the main inertial navigation is fixedly connected to the body, and can perform pitch and roll motion with the body. The speed and position information measured by the main inertial navigation is used as the initial value or measurement information of the sub-inertial navigation after lever arm compensation and delay compensation. Since there is a certain installation error between the sub-INS and the main INS, the main INS information cannot be used directly. It is necessary to obtain the initial attitude of the sub-INS through the transfer alignment method of dynamic information matching, that is, the transfer alignment method can be used to obtain the initial navigation parameters of the sub-INS.

[0060] The delay module is used to obtain the delay parameter of the first navigation module according to the time when the information of the first navigation module is detected to be transmitted to the calculation module and the time when the information of the second navigation module is detected to be transmitted to the calculation module.

[0061] The calculation module is used to calculate the misalignment angle and speed error of the second navigation module according to the delay parameter of the first navigation module.

[0062] In one embodiment, when the fixed-wing aircraft body pitches, rolls, accelerates, decelerates, etc. during movement, the main inertial navigation system connected to the fixed-wing aircraft body and the sub-inertial navigation system in the satellite communication terminal antenna simultaneously measure the angular velocity and acceleration changes of the fixed-wing aircraft. Due to the delay, the main inertial navigation information arrives at the carrier's satellite communication terminal navigation solution computer at time A lags behind the sub-inertial navigation information arriving at the navigation solution computer at time B.

[0063] In one embodiment, when the carrier rotates, the time for the measurement information of the first navigation module to be transmitted to the calculation module is T MINS The time for the measurement information of the second navigation module to be transmitted to the calculation module is T SINS The delay parameter of the first navigation module obtained by the delay module is δt=T MINS -T SINS , where the misalignment angle error of the second navigation module is The velocity error of the second navigation module is That is, when the fixed-wing aircraft body is rotating, the angular velocity error of the main inertial navigation and the sub-inertial navigation output body rotating around a certain carrier coordinate system axis increases due to the delay, so the main inertial navigation delay to be estimated is δt = T MINS -T SINS ;

[0064] The misalignment angle relationship caused by the main inertial navigation delay at the same time is:

[0065]

[0066] The velocity error relationship caused by the main inertial navigation delay at the same time is:

[0067]

[0068] From the above two equations, it can be seen that when the fixed-wing aircraft moves at a constant speed and the attitude angle deflection is very small, the misalignment angle and speed error affected by the main inertial navigation delay are small. However, when the fixed-wing aircraft makes a large angle deflection or accelerates and decelerates, the misalignment angle and speed error affected by the main inertial navigation delay are obvious, so that the system can obtain the observability of the moving antenna inertial navigation delay by observing the misalignment angle and speed error.

[0069] The construction module is used to construct a state equation according to the misalignment angle of the second navigation module, the speed error and the delay parameter of the second navigation module as state quantities.

[0070] In one embodiment, the construction module obtains the misalignment angle φ of the second navigation module n , velocity error δv n , gyro zero position ε b , plus zero position The installation error system state μ, and the delay parameter of the first navigation module is δt, and the construction state equation is obtained. The state equation is:

[0071]

[0072]

[0073]

[0074] in is the projection of the carrier's navigation system's angular velocity of rotation relative to the earth on the carrier's navigation system;

[0075] The Euler angle rotation matrix from the coordinate system formed by the gyroscope sensitive axis of the second navigation module to the n-system;

[0076] f nis the navigation system overload acceleration (specific force) of the carrier;

[0077] The gyro angular velocity measurement white noise of the second navigation module;

[0078] is the accelerometer specific force measurement white noise of the second navigation module;

[0079] The Euler angle rotation matrix from the coordinate system formed by the gyroscope sensitive axis of the first navigation module to the n-system; is the attitude noise of the first navigation module;

[0080] V v is the speed noise.

[0081] According to the above equation, the Kalman filter is used to estimate the state quantities of the sub-INS. When the covariance of the misalignment angle, velocity error and installation error angle of the filter converges to a certain level, the alignment can be completed. After the state quantity estimation is completed using the Kalman filter, the feedback correction method is used to correct the error of the INS system.

[0082] The alignment module is used to estimate the state quantity of the second navigation module according to the state equation by using the Kalman filter and to correct the system error by the feedback correction method.

[0083] In one embodiment, full feedback or partial feedback may be used according to system requirements, and the feedback principle is as follows. According to the error estimation state equation, the estimated state quantity is:

[0084]

[0085] Where K f is the feedback factor, X f The feedback correction is used to correct the system navigation parameters. The residual error is used for subsequent filter updates. f ≠I is called partial feedback. f

[0086] When =I, it is called complete feedback.

[0087] In one embodiment, K f The design method of depends on the requirements of the recipients of the navigation parameters. It can be designed as a linear feedback form or an exponential feedback form. f The smaller the K, the smoother the navigation output. f The larger the value, the more likely it is that the navigation parameters may jump when the measurement information is valid.

[0088] The present application proposes a satellite communication antenna inertial navigation delay compensation system when the navigation information of the carrier is used as the measurement information of the main inertial navigation input in the satellite communication terminal, because the delay of the main inertial navigation information affects the beam pointing accuracy of the phased array. The system includes a first navigation module, a second navigation module, a delay module, a calculation module, a construction module and an alignment module. Then, by establishing a combined navigation state space model including a delay error, the input delay of the first navigation module is estimated when the carrier has a significant attitude angle deflection. At the same time, when the information of the first navigation module is used as the combined navigation observation information, delay compensation is performed to improve the attitude estimation accuracy of the carrier. The system has the advantages of simple operation and the function of adapting to the random delay of the main inertial navigation.

[0089] Figure 3 1 is a flow chart of a method for compensating inertial navigation delay of a mobile communication antenna shown in an embodiment of the present application. The present application proposes a method for compensating inertial navigation delay of a mobile communication antenna as follows:

[0090] Step 1: Collect the angular velocity and acceleration data of the first navigation module through the calculation module, and record the time of collecting the data.

[0091] In one embodiment, the first navigation module includes a first inertial sensor and a first GNSS position sensor, the first inertial sensor is installed on the three axes of the carrier coordinate system, and is used to measure the angular velocity of the carrier's attitude rotation and the component values ​​of the motion acceleration on the three axes. That is, the main inertial navigation used includes the first inertial sensor and the first GNSS position sensor, the first inertial sensor also includes three gyroscopes and three accelerometers, the three gyroscopes are respectively installed on the three axes of the carrier coordinate system for measuring and outputting the component values ​​of the angular velocity of the carrier's attitude rotation on the three axes, and the three accelerometers are also respectively installed on the three axes of the carrier coordinate system for measuring and outputting the component values ​​of the carrier's motion acceleration on the three axes. The first GNSS position sensor is used to measure and output the geographic location of the carrier. That is, the angular velocity of the carrier is obtained by the gyroscope of the first navigation module, and the acceleration of the carrier is obtained by the accelerometer of the first navigation module.

[0092] In one embodiment, the computing module is a strapdown inertial navigation solution computer, which fuses the attitude information, velocity information, acceleration information and position information measurement values ​​obtained by the first navigation module through an algorithm, and then constructs the attitude matrix, velocity matrix and position matrix respectively with the help of the quaternion method, and then calculates the attitude angle and position of the carrier by solving the kinematic differential equation of the quaternion.

[0093] Step 2: Collect the angular velocity and acceleration of the second navigation module through the calculation module, and record the time of collecting the data. In this embodiment, step 1 and step 2 are performed simultaneously.

[0094] In one embodiment, the second navigation module includes a second inertial sensor and a second GNSS position sensor, and the second inertial sensor is installed on the three axes of the carrier coordinate system, and is used to measure the angular velocity of the carrier's attitude rotation and the component values ​​of the motion acceleration on the three axes. That is, the sub-inertial navigation used includes a second inertial sensor and a second GNSS position sensor, and the second inertial sensor also includes three gyroscopes and three accelerometers, and the three gyroscopes are respectively installed on the three axes of the carrier coordinate system for measuring and outputting the component values ​​of the angular velocity of the carrier's attitude rotation on the three axes, and the three accelerometers are also respectively installed on the three axes of the carrier coordinate system for measuring and outputting the component values ​​of the carrier's motion acceleration on the three axes. The second GNSS position sensor is used to measure and output the geographic location of the carrier. That is, the angular velocity of the carrier is obtained again through the gyroscope of the second navigation module, and the acceleration of the carrier is obtained again through the accelerometer of the first navigation module.

[0095] Step 3: Control a carrier to perform pitch, roll and acceleration actions, collect the time when the information of the first navigation module is transmitted to the calculation module and the time when the information of the second navigation module is transmitted to the calculation module again, and obtain the delay parameter of the first navigation module.

[0096] Step 4: constructing an observation model of the carrier according to the obtained delay parameters. Constructing the observation model of the carrier according to the obtained delay parameters further includes:

[0097] The time for controlling the carrier to rotate and collecting the measurement information of the first navigation module and transmitting it to the calculation module is T MINS The time for collecting the measurement information of the second navigation module and transmitting it to the calculation module is T SINS , the delay parameter is δt=T MINS -T SINS ;

[0098] The misalignment angle observation model of the second navigation module is calculated by a calculation module. The misalignment angle observation model is:

[0099] The speed error observation model of the second navigation module is obtained by calculating the calculation module. The speed error observation model is:

[0100] Step 5: According to the observation model, the Kalman filter is used as the transfer alignment filter to establish the system state equation.

[0101] In one embodiment, the present application adopts the transfer alignment method to obtain the initial navigation parameters of the sub-INS, but the transfer alignment requires the carrier to make certain carrier motions to ensure the system alignment accuracy. The present application adopts the "speed + attitude" matching method, which has a wide range of adaptability to the carrier's maneuverability and fast convergence speed. Considering the main INS delay, the sub-INS misalignment angle φ is selected n , sub-INS velocity error δv n , the zero position of the inertial gyro ε b , sub-inertial navigation plus zero position The sub-INS installation error system state μ and the main INS delay are used as the state quantity δt to construct the state equation. Therefore, according to the observation model, the Kalman filter is used as the transfer alignment filter to establish the system state equation further includes:

[0102] A building module is used to construct a state equation according to the misalignment angle of the second navigation module, the speed error and the delay parameter of the second navigation module as state quantities:

[0103]

[0104]

[0105]

[0106] in is the projection of the carrier's navigation system's angular velocity of rotation relative to the earth on the carrier's navigation system; The Euler angle rotation matrix from the coordinate system formed by the gyroscope sensitive axis of the second navigation module to the n-system;

[0107] f n is the overload acceleration (specific force) of the navigation system of the carrier;

[0108] The gyro angular velocity measurement white noise of the second navigation module;

[0109] is the accelerometer specific force measurement white noise of the second navigation module;

[0110] The Euler angle rotation matrix from the coordinate system formed by the gyroscope sensitive axis of the first navigation module to the n-system; is the attitude noise of the first navigation module;

[0111] V v is the speed noise.

[0112] Step 6: Use the installation delay estimate obtained by Kalman filtering to correct the error of the inertial navigation delay of the moving antenna using the feedback correction method based on the delay estimate.

[0113] The estimating the installation error delay obtained by Kalman filtering estimation and correcting the error of the inertial navigation delay of the moving antenna using a feedback correction method according to the delay estimation further comprises:

[0114] According to the error estimation state equation, the estimated state quantity is:

[0115]

[0116] Where K f is the feedback factor, X f The feedback correction is used to correct the system navigation parameters. The residual error is used for subsequent filter updates. f ≠I is called partial feedback. f

[0117] When =I, it is called complete feedback.

[0118] Please refer to Figure 4 , Figure 4 Another flow chart of the method for compensating the delay of an inertial navigation antenna in motion according to an embodiment of the present application is shown. In one embodiment, step three also includes:

[0119] S31, accurately calibrating the response delay T of the first navigation module relative to the data collection time of the second navigation module;

[0120] S32, the strapdown inertial navigation solution computer collects data from the second navigation module in real time, and continuously performs the first strapdown solution in real time, and uses the first strapdown solution result as the output of the navigation system of the carrier;

[0121] S33, storing the latest raw data of the second navigation module greater than the above-mentioned response delay T in the system, and combining and filtering the output data of the first navigation module and the data of the second navigation module before the above-mentioned response delay T, correcting the error of the inertial device in the second navigation module by filtering, and starting the second set of strapdown solution with the above-mentioned filtering result as the initial value;

[0122] S34. When the second set of strapdown solutions is calculated to the current moment, the first set of strapdown solutions are replaced by the second set of strapdown solutions, so as to improve the accuracy of the first set of strapdown solutions.

[0123] In one of the embodiments, the second set of strapdown solution in the step S34 continuously reads and calculates the data of the stored second navigation module, and the combined filtering and the second set of strapdown solution must all complete the processing of the raw data of the second navigation module before the data of the first navigation module with the next response delay arrives, and the calculation result at the current moment is sent to the first set of strapdown solution, and the second set of strapdown solution terminates. The error of the inertial device in the second navigation module corrected by filtering, the inertial device error of the first navigation module must be included in the filtering model as a state variable, and the inertial device error of the first navigation module is estimated and then compensated in the first set and the second set of strapdown solution, so as to improve the accuracy of the raw data of the second navigation module. That is, the speed and position information measured by the main inertial navigation is used as the initial value or measurement information of the sub-inertial navigation after the lever arm compensation and delay compensation. Since there is also a certain installation error between the sub-inertial navigation installation and the main inertial navigation, the main inertial navigation information cannot be used directly, and the initial attitude of the sub-inertial navigation needs to be obtained by the transfer alignment method of dynamic information matching, that is, the initial navigation parameters of the sub-inertial navigation can be obtained by the transfer alignment method. That is, the first step is to collect the angular velocity and specific force data output by the main inertial navigation and the sub-inertial navigation through the strapdown inertial navigation solution computer, and record the time of data collection, accurate to ms; the second step is that when the carrier makes pitch, roll, acceleration and other actions, the main inertial navigation delay has a greater impact on the speed and attitude error, and the observability is better; the third step is to establish a transfer alignment error state equation model including the main inertial navigation delay error. In the second step, the observability of the main inertial navigation delay in the model is improved, and after transfer alignment, the delay estimate after Kalman filtering is obtained; the fourth step is to estimate the delay and use the feedback correction method to correct the error to improve the satellite tracking accuracy.

[0124] The technical solution provided by the present application may include the following beneficial effects: When the navigation information of the carrier is used as the main inertial navigation input measurement information of the satellite communication terminal, the main inertial navigation information delay affects the phased array beam pointing accuracy, and a moving antenna inertial navigation delay compensation method based on transfer alignment is proposed. This method estimates the main inertial navigation input delay when the carrier has a significant attitude angle deflection by establishing a combined navigation state space model containing delay errors, and at the same time, performs delay compensation when using the main inertial navigation information as combined navigation observation information to improve the attitude estimation accuracy. It has the advantages of simple operation and adaptability to the random delay of the main inertial navigation.

[0125] The embodiments of the present application have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The selection of terms used herein is intended to best explain the principles of the embodiments, practical applications, or improvements to the technology in the market, or to enable other persons of ordinary skill in the art to understand the embodiments disclosed herein.

Claims

1. A moving antenna inertial navigation delay compensation system, characterized in that: include: A first navigation module, installed on the carrier, for measuring the carrier's attitude, speed and position in real time; A second navigation module is provided on the antenna of the satellite communication terminal of the carrier, and is used to directly measure the angular velocity and acceleration of the satellite communication terminal; A delay module, used to obtain a delay parameter of the first navigation module according to the time when the information of the first navigation module is detected to be transmitted to the calculation module and the time when the information of the second navigation module is detected to be transmitted to the calculation module; A calculation module, used for calculating the misalignment angle and speed error of the second navigation module according to the delay parameter of the first navigation module; A construction module, used for constructing a state equation according to the misalignment angle of the second navigation module, the speed error and the delay parameter of the second navigation module as state quantities; The alignment module is used to estimate the state quantity of the second navigation module according to the state equation by using the Kalman filter and to correct the system error by the feedback correction method.

2. The inertial navigation delay compensation system for mobile communication antenna according to claim 1 is characterized by: The satellite communication terminal is fixed on the platform of the carrier and is located above the rolling axis of the carrier. The installation plane of the first navigation module on the surface of the carrier is the same plane as the installation plane of the satellite communication antenna on the surface of the carrier.

3. The inertial navigation delay compensation system for mobile communication antenna according to claim 2 is characterized in that: The installation plane of the second navigation module is parallel to the moving direction of the carrier and is parallel to the installation plane of the first navigation module.

4. The inertial navigation delay compensation system for mobile communication antenna according to claim 3 is characterized by: The first navigation module includes a first inertial sensor and a first GNSS position sensor. The first inertial sensor is installed on three axes of the carrier coordinate system and is used to measure the angular velocity of the carrier attitude rotation and the component values ​​of the motion acceleration on the three axes.

5. The inertial navigation delay compensation system for mobile communication antenna according to claim 4 is characterized in that: When the carrier rotates, the time for the measurement information of the first navigation module to be transmitted to the calculation module is T MINS The time for the measurement information of the second navigation module to be transmitted to the calculation module is T SINS The delay parameter of the first navigation module obtained by the delay module is δt=T MINS -T SINS , where the misalignment angle error of the second navigation module is The velocity error of the second navigation module is 6. The inertial navigation delay compensation system for mobile communication antenna according to claim 5 is characterized by: The construction module obtains the misalignment angle φ of the second navigation module n , velocity error δv n , gyro zero position ε b , plus zero position The installation error system state μ, and the delay parameter of the first navigation module is δt, and the construction state equation is obtained. The state equation is: in is the projection of the carrier's navigation system's angular velocity of rotation relative to the earth on the carrier's navigation system; The Euler angle rotation matrix from the coordinate system formed by the gyroscope sensitive axis of the second navigation module to the n-system; f n is the navigation system overload acceleration (specific force) of the carrier; The gyro angular velocity measurement white noise of the second navigation module; is the accelerometer specific force measurement white noise of the second navigation module; The Euler angle rotation matrix from the coordinate system formed by the gyroscope sensitive axis of the first navigation module to the n-system; is the attitude noise of the first navigation module; V v is the speed noise.

7. A method for compensating inertial navigation delay of a moving antenna, characterized in that: Collecting the angular velocity and acceleration data of the first navigation module through the calculation module, and recording the time of collecting the data; The angular velocity and acceleration of the second navigation module are collected by the calculation module, and the time of collecting the data is recorded; Control a carrier to perform pitch, roll, and acceleration actions, collect the time when the information of the first navigation module is transmitted to the calculation module and the time when the information of the second navigation module is transmitted to the calculation module again, and obtain the delay parameter of the first navigation module; According to the obtained delay parameters, an observation model of the carrier is constructed; According to the observation model, a Kalman filter is used as a transfer alignment filter to establish a system state equation; The installation error delay estimated by Kalman filtering is used to correct the error of the inertial navigation delay of the moving antenna using the feedback correction method based on the delay estimate.

8. The method for inertial navigation delay compensation of a moving antenna according to claim 7, characterized in that: The constructing of the observation model of the carrier according to the obtained delay parameter further comprises: The time for controlling the carrier to rotate and collecting the measurement information of the first navigation module and transmitting it to the calculation module is T MINS The time for collecting the measurement information of the second navigation module and transmitting it to the calculation module is T SINS , the delay parameter is δt=T MINS -T SINS ; The misalignment angle observation model of the second navigation module is calculated by a calculation module. The misalignment angle observation model is: The speed error observation model of the second navigation module is obtained by calculating the calculation module. The speed error observation model is:

9. The method for inertial navigation delay compensation of a moving antenna according to claim 8, characterized in that: According to the observation model, the Kalman filter is used as the transfer alignment filter, and the system state equation is established further including: A building module is used to construct a state equation according to the misalignment angle of the second navigation module, the speed error and the delay parameter of the second navigation module as state quantities: in is the projection of the carrier's navigation system's angular velocity of rotation relative to the earth on the carrier's navigation system; The Euler angle rotation matrix from the coordinate system formed by the gyroscope sensitive axis of the second navigation module to the n-system; f n is the navigation system overload acceleration (specific force) of the carrier; The gyro angular velocity measurement white noise of the second navigation module; is the accelerometer specific force measurement white noise of the second navigation module; The Euler angle rotation matrix from the coordinate system formed by the gyroscope sensitive axis of the first navigation module to the n-system; is the attitude noise of the first navigation module; V v is the speed noise.

10. The method for inertial navigation delay compensation of a moving antenna according to claim 9, characterized in that: The estimating the installation error delay obtained by Kalman filtering estimation and correcting the error of the inertial navigation delay of the moving antenna using a feedback correction method according to the delay estimation further comprises: According to the error estimation state equation, the estimated state quantity is: Where K f is the feedback factor, X f The feedback correction is used to correct the system navigation parameters. The residual error is used for subsequent filter updates. f ≠I is called partial feedback. f When =I, it is called complete feedback.

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