Instrument landing system ILS geometric modeling method and simulation system

Abstract

The invention belongs to the technical field of instrument landing system ILS equipment testing, and particularly relates to an instrument landing system ILS geometric modeling method which comprises the steps that 1, the working principle of an instrument landing system ILS is analyzed, internal constituent elements of the instrument landing system ILS are obtained through decomposition, the external interaction process of the system is obtained through carding, and the logic relation of the instrument landing system ILS is obtained; and 2, based on the ILS logic relationship of the instrument landing system, establishing an ILS geometric model of the instrument landing system, and outputting a course deflection angle and a glide deflection angle through three steps of coordinate conversion, vector calculation and deflection angle solving. In addition, the invention designs an instrument landing system ILS simulation system implemented based on the instrument landing system ILS geometric modeling method.

Description

Technical Field

[0001] The present application belongs to the technical field of instrument landing system (ILS) equipment testing, and specifically relates to an instrument landing system (ILS) geometric modeling method and simulation system. Background Art

[0002] The instrument landing system ILS, also known as the blind landing system, is used to provide an approach landing channel for the aircraft to land when the pilot cannot visually see reference objects during flight, ensuring the safe landing of the aircraft.

[0003] The instrument landing system (ILS) is an important part of the aircraft avionics mission system, including ground equipment and airborne equipment. The ground equipment of the instrument landing system (ILS) is the transmitting equipment, which is generally composed of three parts: the localizer, the glide path beacon and the marker beacon. The localizer is used to provide heading guidance, the glide path beacon is used to provide vertical guidance, and the marker beacon is used to provide distance guidance. The airborne equipment of the instrument landing system (ILS) includes a receiver and a processing unit, wherein the receiver includes a very high frequency heading receiver, an ultra-high frequency glide path receiver and a very high frequency pointing receiver corresponding to the ground transmitting equipment.

[0004] There are currently two main ways to test the instrument landing system (ILS) equipment: ground detection and flight verification. Among them, ground detection is mainly to calibrate the equipment parameters such as its operating frequency and transmission power, and to test parameters such as DDM value, SDM value, RF level, and antenna phasing at different test points in the field; flight verification is mainly to use aircraft equipped with proprietary instruments to conduct aerial inspections of ground navigation equipment and navigation lighting facilities, adjust the equipment to a specified working state, and provide accurate and reliable information for the aircraft.

[0005] The avionics mission system laboratory of the aircraft general design unit is responsible for the system-level ground integration and joint testing of various airborne equipment. The design verification and ground verification of the instrument landing system ILS mainly verify whether the cross-linking function of the instrument landing system ILS and subsystems such as display control, radio navigation and flight management is normal and whether the data interface is correct. In order to complete the functional verification of airborne equipment such as the instrument landing system ILS receiver and processing unit in the avionics mission system laboratory, it is necessary to build the necessary simulation and incentive data sources to simulate the real flight operation and ground interaction process in the air, so as to verify the functional response of the equipment itself and the functional status between the equipment.

[0006] The avionics mission system laboratory has a complete set of airborne equipment test pieces, has built an environmental simulation platform represented by flight simulation, and has established scientific testing methods covering manual testing and automatic testing. However, the modeling and simulation of the instrument landing system (ILS) is still in the exploratory stage.

[0007] According to the traditional forward design concept, the conventional approach to simulating ILS equipment is to model the ground beacon, localizer antenna and airborne receiving equipment according to its equipment composition and operation mode, and use communication simulation software to simulate input and output data under an ideal channel environment. This modeling method has high requirements for underlying professional details and requires an in-depth understanding of the composition, devices, and precise signal decomposition and calculation of ILS equipment. It is difficult and cannot be applied to the verification of various different types of ILS equipment.

[0008] This application is proposed in view of the above-mentioned technical defects. Summary of the invention

[0009] The purpose of the present application is to provide an instrument landing system (ILS) geometric modeling method and simulation system to overcome or alleviate at least one of the known technical deficiencies.

[0010] The technical solution of this application is:

[0011] On the one hand, a method for geometric modeling of an instrument landing system (ILS) is provided, comprising:

[0012] Step 1: Analyze the working principle of the instrument landing system (ILS), decompose the internal components of the ILS system, sort out the external interaction process of the system, and derive the logical relationship of the ILS system;

[0013] Step 2: Based on the logical relationship of the instrument landing system (ILS), an ILS geometric model is established. After three steps of coordinate conversion, vector calculation, and angle solution, the output is the heading angle and the glide path angle.

[0014] According to at least one embodiment of the present application, in the above-mentioned instrument landing system ILS geometric modeling method, in step one, the instrument landing system logical relationship input initialization parameters are the geographical coordinates and azimuth of the runway entrance, the installation position of the glide path relative to the runway entrance, and the installation position of the localizer relative to the runway entrance, and the output is the deviation angle of the aircraft relative to the ideal localizer and glide path, that is, the heading deviation angle and the glide path deviation angle.

[0015] According to at least one embodiment of the present application, in the above-mentioned instrument landing system ILS geometric modeling method, in step 2, in the design of the instrument landing system ILS geometric model, a runway coordinate system is established with the runway entrance as the origin and the runway approach direction as the axis, and the three-dimensional coordinates of the aircraft, localizer, and glide path in the runway coordinate system are solved by using geographical and geometric calculation functions.

[0016] According to at least one embodiment of the present application, in the above-mentioned instrument landing system ILS geometric modeling method, in step 2, an instrument landing system ILS geometric model is designed in a flight simulation platform, and the coordinate data conversion of the geographic coordinates and azimuth of the runway entrance, the installation position of the glide path relative to the runway entrance, and the installation position of the localizer relative to the runway entrance is completed according to the three-dimensional coordinate system of the simulation environment space.

[0017] According to at least one embodiment of the present application, in the above-mentioned instrument landing system ILS geometric modeling method, in step 2, an instrument landing system ILS geometric model is designed, and the relative offset between the real-time position of the aircraft, the ground platform and the glide path is calculated, and the heading angle and the glide path angle are calculated according to a pre-set upper limit of the offset.

[0018] According to at least one embodiment of the present application, in the above-mentioned instrument landing system ILS geometric modeling method,

[0019] In step 2, in the design of the ILS geometric model, the heading angle is calculated as follows:

[0020] gsHeading=tan(aitcraft positon ,navaid geod )×180÷π;

[0021] in,

[0022] gsHeading is the heading angle; aitcraft positon is the three-dimensional coordinate of the aircraft; navaid geod is the three-dimensional coordinate of the localizer; tan represents the reuse of the tangent function, and the horizontal tangent value is calculated by the three-dimensional coordinates of the two points.

[0023] According to at least one embodiment of the present application, in the above-mentioned ILS geometric modeling method, in step 2, in designing the ILS geometric model, the glide slope angle is calculated as follows:

[0024] gsDirect=atan2[-dot(pos,),dot(pos,gsVertical)]×180÷π;

[0025] in,

[0026] gsDirect is the glide path angle; pos is the position vector between the aircraft position and the glide path; gsAxis is the vector tangent in the runway direction; gsVertical is the vector tangent in the vertical direction; dot represents the component calculation function, which calculates the position component in the tangent direction through the position vector and the vector tangent; atan2 represents the reuse of the inverse tangent function, which calculates the inverse tangent value expressed in radians through two position components.

[0027] According to at least one embodiment of the present application, in the above-mentioned ILS geometric modeling method, in step 2, the ILS geometric model is designed to calculate the climbing speed, specifically:

[0028] climbRate=sin[(gsDirect-10*deflectionAngle)×180÷π]×horiz_vel×3.2808;

[0029] in

[0030] climbRate is the climbing speed; deflectionAngle is the aircraft deflection angle calculated from the perspective of the ground equipment; horiz_vel is the aircraft relative horizontal speed calculated from the perspective of the ground equipment; sin represents the sine function.

[0031] On the other hand, an instrument landing system ILS simulation system is provided, including a geometric model function module, an approach initial setting module, an approach process monitoring module, and a calculation data monitoring module;

[0032] The geometric model function module constructs an instrument landing system ILS geometric model, and the instrument landing system ILS geometric model is constructed by the instrument landing system ILS geometric modeling method mentioned above;

[0033] The initial approach setting module is used to set the basic scenario of the instrument landing system (ILS) and provide input for the ILS geometric model.

[0034] The approach process monitoring module is used to display the entire approach process in a planar manner.

[0035] The calculation data monitoring module is used to monitor the changes in the calculation data of the instrument landing system (ILS) geometric model during the approach process.

[0036] According to at least one embodiment of the present application, in the above-mentioned instrument landing system ILS simulation system, in the data connection setting module:

[0037] The basic scenario of the instrument landing system ILS is set in the approach initial setting module, including airport selection, runway selection, approach status, and approach frequency setting parameters. The approach status includes distance, altitude, and speed. After the parameters are set, the scenario overview can be previewed in the airport diagram.

[0038] According to at least one embodiment of the present application, in the above-mentioned instrument landing system ILS simulation system, in the data connection setting module:

[0039] The calculation data monitoring module monitors the changes in the instrument landing system (ILS) geometric model calculation data during the approach process, including heading deviation angle, glide path deviation angle, and intermediate data of distance, validity, and indicated direction.

[0040] According to at least one embodiment of the present application, in the above-mentioned instrument landing system ILS simulation system, in the data connection setting module:

[0041] Also includes a data connection setup module;

[0042] The data connection setting module is used to set the data connection status of the geometric model function module to match the online and offline modes of the instrument landing system ILS airborne equipment.

[0043] According to at least one embodiment of the present application, in the above-mentioned instrument landing system ILS simulation system, in the data connection setting module:

[0044] In the online mode of the instrument landing system ILS airborne equipment, the geometric model function module is set as the excitation data source, and the heading angle and glide path angle calculated by the instrument landing system ILS geometric model are sent to the instrument landing system ILS exciter. The exciter then converts the data into DDM electrical data and forwards it to the airborne receiver, thereby driving the airborne equipment to complete the landing guidance function.

[0045] In the mode where the onboard equipment of the instrument landing system (ILS) is offline, the geometric model function module is set to replace the onboard equipment to interact with the display control subsystem. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 is a schematic diagram of an instrument landing system ILS geometric modeling method provided in an embodiment of the present application;

[0047] Figure 2 is a schematic diagram of the logical relationship of the instrument landing system ILS provided in an embodiment of the present application;

[0048] Figure 3 is a schematic diagram of an instrument landing system ILS simulation system provided by an embodiment of the present application;

[0049] Figure 4is an operation diagram of an approach initial setting module provided in an embodiment of the present application;

[0050] Figure 5 is an operation diagram of an approach process monitoring module provided in an embodiment of the present application;

[0051] Figure 6 is an interface diagram of a calculation data monitoring module provided in an embodiment of the present application;

[0052] Figure 7 This is an interface diagram of the data connection setting module provided in an embodiment of the present application.

[0053] In order to better illustrate the present embodiment, some parts of the drawings may be omitted, enlarged or reduced, and do not represent the size of the actual product. In addition, the drawings are only used for illustrative purposes and should not be construed as limitations on the present application. DETAILED DESCRIPTION

[0054] In order to make the technical solution and advantages of the present application clearer, the technical solution of the present application will be described in further detail in detail and in detail with reference to the accompanying drawings. It can be understood that the specific embodiments described here are only partial embodiments of the present application, which are only used to explain the present application, not to limit the present application. It should be noted that, for the convenience of description, only the parts related to the present application are shown in the accompanying drawings, and other related parts can refer to the general design.

[0055] In addition, unless otherwise defined, the technical terms or scientific terms used in the description of this application shall have the usual meanings understood by those of ordinary skill in the art to which this application belongs. The words used in the description of this application to indicate orientation are only used to indicate relative directions or positional relationships. When the absolute position of the described object changes, its relative positional relationship may also change accordingly. The word "include" used in the description of this application indicates that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, but does not exclude other elements or objects.

[0056] In addition, it should be noted that, unless otherwise clearly specified and limited, the words "installation", "connection" and similar terms used in the description of this application should be understood in a broad sense. For example, the connection can be a fixed connection or a detachable connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. Technical personnel in the field can understand its specific meaning in this application according to the specific circumstances.

[0057] A geometric modeling method for instrument landing system ILS, such as Figure 1 shown.

[0058] Step 1: Analyze the working principle of the instrument landing system (ILS), decompose the internal components of the ILS system, sort out the external interaction process of the system, and derive the logical relationship of the ILS system.

[0059] The working principle of the instrument landing system ILS is to use two independent ground radio transmitters to detect the modulation difference DDM during the approach process through the airborne receiver, and calculate the heading angle and glide angle of the aircraft from the reference course, such as Figure 2 As shown, the information is processed and passed to two indicators on the cockpit display to provide the pilot with accurate lateral and vertical landing guidance. The lateral landing guidance is a guidance pointer that moves left and right to indicate the position of the heading indicator signal; the vertical landing guidance is a guidance pointer that moves up and down to point to the position of the glide path and guide the trend.

[0060] The input initialization parameters of the instrument landing system logic relationship are the geographic coordinates and azimuth of the runway entrance, the installation position of the glide path relative to the runway entrance, and the installation position of the localizer relative to the runway entrance. The output is the deviation angle of the aircraft relative to the ideal localizer and glide path, that is, the heading deviation angle and the glide path deviation angle.

[0061] Step 2: Based on the logical relationship of the instrument landing system (ILS), the geometric model of the instrument landing system (ILS) is established. After three steps of coordinate conversion, vector calculation, and angle solution, the output is the heading angle and the glide slope angle. Figure 2 shown.

[0062] In the ILS geometric model of the instrument landing system, a runway coordinate system is established with the runway entrance as the origin and the runway approach direction as the axis. The three-dimensional coordinates of the aircraft, localizer, and glide path in the runway coordinate system are solved by using geographical and geometric calculation functions.

[0063] In the flight simulation platform, the geometric model of the instrument landing system (ILS) completes the coordinate data conversion of the geographic coordinates and azimuth of the runway entrance, the installation position of the glide path relative to the runway entrance, and the installation position of the localizer relative to the runway entrance according to the three-dimensional coordinate system of the simulation environment space.

[0064] In the ILS geometric model, the relative offset between the real-time position of the aircraft, the ground platform and the glide path is calculated. According to the preset upper limit of the offset, the heading angle and the glide path angle are calculated as follows:

[0065] gsHeading=tan(aitcraft positon ,navaid geod )×180÷π;

[0066] in,

[0067] gsHeading is the heading angle; aitcraft positon is the three-dimensional coordinate of the aircraft; navaid geod is the three-dimensional coordinate of the localizer; tan represents the reuse of the tangent function, and the horizontal tangent value is calculated by the three-dimensional coordinates of the two points.

[0068] gsDirect=atan2[-dot(pos,),dot(pos,gsVertical)]×180÷π;

[0069] in,

[0070] gsDirect is the glide path angle; pos is the position vector between the aircraft position and the glide path; gsAxis is the vector tangent in the runway direction; gsVertical is the vector tangent in the vertical direction; dot represents the component calculation function, which calculates the position component in the tangent direction through the position vector and the vector tangent; atan2 represents the reuse of the inverse tangent function, which calculates the inverse tangent value expressed in radians through two position components.

[0071] The ILS geometric model can further calculate the climb speed as follows:

[0072] climbRate=sin[(gsDirect-10*deflectionAngle)×180÷π]×horiz_vel×3.2808;

[0073] in

[0074] climbRate is the climbing speed; deflectionAngle is the aircraft deflection angle calculated from the perspective of the ground equipment; horiz_vel is the aircraft relative horizontal speed calculated from the perspective of the ground equipment; sin represents the sine function.

[0075] The ILS geometric modeling method disclosed in the above embodiment starts with the working principle of the ILS and establishes a geometric model used in three-dimensional space. The relative operation process of the ILS and the aircraft position can be constructed through programmed simulation, and the dynamic data of the horizontal heading guidance and the vertical glide guidance can be calculated, so as to stimulate the normal operation of the ILS airborne receiving and processing unit and verify whether its function is normal.

[0076] The ILS geometric modeling method disclosed in the above embodiment and the simulation data obtained by calculating the ILS geometric model can be used as an excitation data source to support the cross-linking verification of the ILS and airborne equipment such as the display and control in the avionics mission system, and can also be used as a simulation device to replace the airborne ILS equipment to work independently. Based on this, the present application further provides an ILS simulation system, including a geometric model function module, an approach initial setting module, an approach process monitoring module, a calculation data monitoring module, and a data connection setting module. Figure 3 shown.

[0077] An instrument landing system (ILS) geometric model is constructed in the geometric model function module. The instrument landing system (ILS) geometric model is constructed by the instrument landing system (ILS) geometric modeling method disclosed in the above embodiment.

[0078] The initial approach setting module is used to set the basic scenario of the instrument landing system (ILS), including parameters such as airport selection, runway selection, approach status, and approach frequency setting. The approach status includes distance, altitude, speed, etc., which provides input for the geometric model of the instrument landing system (ILS).

[0079] After the parameters are set, the scene overview can be previewed in the airport diagram, and the geographical conditions and navigation information involved in this approach can be intuitively understood, such as Figure 4 shown.

[0080] The approach process monitoring module is used to display the entire approach process in a planar manner, such as Figure 5 shown.

[0081] The aircraft approach process in three-dimensional space is fast, long, and involves many factors. Non-professional pilots cannot observe and obtain effective information in a timely and comprehensive manner during this process, and are very likely to miss key information and operational links. The two-dimensional dynamic monitoring interface of the approach process monitoring module can help them understand the approach status in real time, make reasonable predictions and actions, and ensure that the entire verification process is reasonable and efficient.

[0082] The calculation data monitoring module is used to monitor the changes in the calculation data of the instrument landing system (ILS) geometric model during the approach process.

[0083] The monitoring data of the calculation data monitoring module include two result data, namely, heading angle and glide angle, as well as intermediate data such as distance, validity, and indication direction. Figure 6 As shown, it is easy to troubleshoot and solve problems.

[0084] The data connection setting module is used to set the data connection status of the geometric model function module to match the online and offline modes of the instrument landing system ILS airborne equipment, and realize data input, output, browsing and setting in both online and offline usage scenarios of the instrument landing system ILS.

[0085] In the online mode of the ILS airborne equipment, the geometric model function module can be set as the excitation data source, and the heading angle and glide path angle calculated by the ILS geometric model of the ILS can be sent to the ILS exciter of the ILS. The exciter then converts the data into DDM electrical data and forwards it to the airborne receiver, thereby driving the airborne equipment to complete the landing guidance function.

[0086] In the offline mode of the instrument landing system ILS airborne equipment, corresponding to the situation that the airborne equipment is not online due to lack of equipment or failure, the geometric model function module is set to replace the airborne equipment to interact with other subsystems such as display control.

[0087] The instrument landing system ILS simulation system disclosed in the above embodiment can support the cross-linking verification of the instrument landing system ILS and airborne equipment such as display and control in the avionics system, and can also be used as a simulation device to replace the airborne instrument landing system ILS equipment to work independently. On the one hand, it can effectively solve the problems of lack of external resources for ground verification and differences in the earth-sky environment. On the other hand, it can solve the problems of high safety pressure, high technical requirements, and high inspection costs in flight inspections. It has great technical value and broad application prospects for improving the verification quality and test efficiency of the instrument landing system ILS and related equipment of the actual avionics mission system.

[0088] In addition, technicians in the field should also be able to realize that the various modules and units of the instrument landing system ILS simulation system disclosed in the embodiments of the present application can be implemented by electronic hardware, computer software or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, this application generally describes them according to their functions. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Technicians in the field can choose to adopt different methods to implement the described functions for each specific application and its actual constraints, but such implementation should not be considered to be beyond the scope of this application.

[0089] So far, the technical solution of the present application has been described in conjunction with the preferred embodiments shown in the accompanying drawings. Those skilled in the art should understand that the scope of protection of the present application is obviously not limited to these specific embodiments. Without departing from the principles of the present application, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the scope of protection of the present application.

Claims

1. An instrument landing system (ILS) geometric modeling method, characterized in that: include: Step 1: Analyze the working principle of the instrument landing system (ILS), decompose the internal components of the ILS system, sort out the external interaction process of the system, and derive the logical relationship of the ILS system; Step 2: Based on the logical relationship of the instrument landing system (ILS), an ILS geometric model is established. After three steps of coordinate conversion, vector calculation, and angle solution, the output is the heading angle and the glide path angle.

2. The ILS geometric modeling method according to claim 1, characterized in that: In step 1, the input initialization parameters of the instrument landing system logic relationship are the geographic coordinates and azimuth of the runway entrance, the installation position of the glide path relative to the runway entrance, and the installation position of the localizer relative to the runway entrance. The output is the deviation angle of the aircraft relative to the ideal localizer and glide path, that is, the heading deviation angle and the glide path deviation angle.

3. The ILS geometric modeling method according to claim 2, characterized in that: In step 2, in the design of the ILS geometric model, a runway coordinate system is established with the runway entrance as the origin and the runway approach direction as the axis. The three-dimensional coordinates of the aircraft, localizer, and glide path in the runway coordinate system are solved by using geographical and geometric calculation functions.

4. The ILS geometric modeling method according to claim 3, characterized in that: In step 2, the geometric model of the instrument landing system (ILS) is designed in the flight simulation platform, and the coordinate data conversion of the geographic coordinates and azimuth of the runway entrance, the installation position of the glide path relative to the runway entrance, and the installation position of the localizer relative to the runway entrance is completed according to the three-dimensional coordinate system of the simulation environment space.

5. The ILS geometric modeling method according to claim 4, characterized in that: In step 2, the geometric model of the instrument landing system (ILS) is designed to calculate the relative offset between the real-time position of the aircraft, the ground platform and the glide path. According to the preset upper limit of the offset, the heading angle and the glide path angle are calculated.

6. The ILS geometric modeling method according to claim 5, characterized in that: In step 2, in the design of the ILS geometric model, the heading angle is calculated as follows: gsHeading=tan(aitcraft positon ,navaid geod )×180÷π; in, gsHeading is the heading angle; aitcraft positon is the three-dimensional coordinate of the aircraft; navaid geod is the three-dimensional coordinate of the localizer; tan represents the reuse of the tangent function, and the horizontal tangent value is calculated by the three-dimensional coordinates of the two points.

7. The ILS geometric modeling method according to claim 6, characterized in that: In step 2, when designing the ILS geometric model, the glide slope angle is calculated as follows: gsDirect=atan2[-dot(pos,),dot(pos,gsVertical)]×180÷π; in, gsDirect is the glide path angle; pos is the position vector between the aircraft position and the glide path; gsAxis is the vector tangent in the runway direction; gsVertical is the vector tangent in the vertical direction; dot represents the component calculation function, which calculates the position component in the tangent direction through the position vector and the vector tangent; atan2 represents the reuse of the inverse tangent function, which calculates the inverse tangent value expressed in radians through two position components.

8. The ILS geometric modeling method according to claim 7, characterized in that: In step 2, the ILS geometric model is designed to calculate the climb speed, specifically: climbRate=sin[(gsDirect-10*deflectionAngle)×180÷π]× horiz_vel×3.2808; in climbRate is the climbing speed; deflectionAngle is the aircraft deflection angle calculated from the perspective of the ground equipment; horiz_vel is the aircraft relative horizontal speed calculated from the perspective of the ground equipment; sin represents the sine function.

9. An instrument landing system (ILS) simulation system, comprising a geometric model function module, an approach initial setting module, an approach process monitoring module, and a calculation data monitoring module; An instrument landing system ILS geometric model is constructed in the geometric model function module, and the instrument landing system ILS geometric model is constructed by the instrument landing system ILS geometric modeling method described in claim 1; The initial approach setting module is used to set the basic scenario of the instrument landing system (ILS) and provide input for the ILS geometric model. The approach process monitoring module is used to display the entire approach process in a planar manner. The calculation data monitoring module is used to monitor the changes in the calculation data of the instrument landing system (ILS) geometric model during the approach process.

10. The instrument landing system (ILS) simulation system according to claim 9, characterized in that: The basic scenario of the instrument landing system ILS is set in the approach initial setting module, including airport selection, runway selection, approach status, and approach frequency setting parameters. The approach status includes distance, altitude, and speed. After the parameters are set, the scenario overview can be previewed in the airport diagram.

11. The ILS geometric modeling method according to claim 10, characterized in that: The calculation data monitoring module monitors the changes in the instrument landing system (ILS) geometric model calculation data during the approach process, including heading deviation angle, glide path deviation angle, and intermediate data of distance, validity, and indicated direction.

12. The instrument landing system (ILS) simulation system according to claim 11, characterized in that: Also includes a data connection setup module; The data connection setting module is used to set the data connection status of the geometric model function module to match the online and offline modes of the instrument landing system ILS airborne equipment.

13. The instrument landing system (ILS) simulation system according to claim 12, characterized in that: In the data connection settings module: In the online mode of the instrument landing system ILS airborne equipment, the geometric model function module is set as the excitation data source, and the heading angle and glide path angle calculated by the instrument landing system ILS geometric model are sent to the instrument landing system ILS exciter. The exciter then converts the data into DDM electrical data and forwards it to the airborne receiver, thereby driving the airborne equipment to complete the landing guidance function. In the mode where the onboard equipment of the instrument landing system (ILS) is offline, the geometric model function module is set to replace the onboard equipment to interact with the display control subsystem.

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