CN112764001A

CN112764001A - Outfield RCS test field

Info

Publication number: CN112764001A
Application number: CN202011568081.7A
Authority: CN
Inventors: 李君哲; 车理论; 胡滨
Original assignee: Shenyang Aircraft Design and Research Institute Aviation Industry of China AVIC
Current assignee: Shenyang Aircraft Design and Research Institute Aviation Industry of China AVIC
Priority date: 2020-12-25
Filing date: 2020-12-25
Publication date: 2021-05-07
Anticipated expiration: 2040-12-25
Also published as: CN112764001B

Abstract

The application belongs to the technical field of RCS testing, and particularly relates to an outfield RCS testing field. The field comprises a main area, an auxiliary area and a tested area, wherein the main area is a rectangular area between the tested equipment and the tested equipment, a laying area is arranged in the main area, three laying sections are formed in the laying area along the direction from the tested equipment to the tested equipment, and the width of the middle laying section is larger than that of the laying sections at two ends; the secondary region surrounds the primary region; the tested area is used for storing the tested equipment, the tested area is arranged to be lower than the ground of the main area in the vertical direction, so that a pit is formed, the pit is in inclined transition towards the main area, and a tip facing the tested equipment is formed in the transition area; wherein, cement is paved on the ground of the paving area, the sub-area and the detected area. The laying area of the test channel is only 17.15% of that of a standard field, the construction cost can be greatly reduced while the field performance is ensured, and the requirement for accurately measuring the radar stealth characteristic of the whole airplane can be met after the test channel is built.

Description

Outfield RCS test field

Technical Field

The application belongs to the technical field of RCS testing, and particularly relates to an outfield RCS testing field.

Background

The stealth performance of stealth airplanes is always the focus of attention, the stealth performance is also listed as the first place by the 4S standard, at present, four methods, namely compact field measurement, outdoor ground field measurement, dynamic flight measurement and indoor near field measurement, are mainly used for measuring the scattering characteristics of stealth airplanes, and the methods are suitable for various stages of airplane design, sizing, production delivery and the like.

The compact range test system is mainly used for accurately measuring a scale model or real parts of an airplane in the design stage of a stealth airplane due to the limitation of the size of a dead zone. The measuring mode has the characteristics of moderate target size, low model processing cost and more favorable design for new models. But the machining precision after the scaling is higher, the similarity of materials (particularly non-uniform media and magnetic materials) is difficult to guarantee, and the problem of test equipment and test fields at higher frequencies is difficult to solve.

The specially constructed outdoor test field is used for testing the scattering characteristics of the whole machine and is mainly used for testing a 1:1 full-size model and a real machine after the whole machine is designed. The test distance is generally large in order to satisfy the far field condition of plane wave incidence and scattering. For example, a ratcat test field on a white sand missile field in the central and south of new mexico occupies more than ten square kilometers, has a test frequency range of 30MHz to 95GHz and a maximum test distance of 2286m, can test a large target of 25m, has a maximum bearing capacity of 22.7t when a low-reflection metal support rotates to the top, and has been used for testing fighters such as F-102.

The dynamic flight test is an indispensable test link after the stealth target has a flight state, the dynamic measurement can completely simulate and measure the real radar section characteristics when the target moves, but the repeatability of the flight attitude and the flight path is poor, so that the method is difficult to judge and guide the improvement of the stealth performance of the aircraft as a quantitative, repeatable and analyzable general test means, and the cost of the dynamic test is very high.

The indoor full-size near-field test is an RCS test technology developed in recent years, and the scattering characteristics of the full-size stealth aircraft target are rapidly and accurately measured through near-field scanning measurement and near-far field transformation technology. The method is mainly used in the stages of complete machine development and complete machine delivery acceptance inspection, and can replace most dynamic flight tests. In the full-size complete machine models of F-22 and F-35 and the stealth detection and authentication evaluation of a real airplane, an indoor full-size near-field test system plays an extremely important role, the test cost is greatly reduced, and the development period of a product is shortened. However, the test requires the construction of a special test laboratory, the investment is huge, the construction period is long, at present, one such laboratory in China is in research construction, only the relevant test technology is in the research stage and cannot be used in a mature way aiming at the field acceptance of a certain type of airplane.

Aiming at the finished airplane of a certain type, various testing fields which are possessed in China at present cannot carry out efficient and accurate measurement on radar scattering cross sections (RCS).

Disclosure of Invention

The invention provides an external field RCS test site for realizing the accurate measurement of the radar stealth characteristic of the whole aircraft, which mainly comprises:

the main area is a rectangular area between the tested equipment and the testing equipment, a laying area is arranged in the main area, three laying sections are formed in the laying area along the direction from the tested equipment to the testing equipment, and the width of the middle laying section is larger than that of the laying sections at two ends;

a secondary region surrounding the primary region;

the tested area is used for storing the tested equipment, the tested area is arranged to be lower than the ground of the main area in the vertical direction so as to form a pit, the pit is in inclined transition towards the main area, and a tip facing the tested equipment is formed in the transition area;

and cement is paved on the pavement area, the auxiliary area and the ground of the detected area.

Preferably, the cement has an unevenness of less than 2 mm.

Preferably, the paving area comprises a first expanding section, a wide section and a second expanding section, wherein the wide section is located in the middle and has the largest width, the first expanding section and the second expanding section respectively extend from two sides of the wide section to two ends of the paving area in a width narrowing trend, the end parts of the first expanding section and the second expanding section are respectively provided with a tip section, and the tip ends of the two tip sections are located on a connecting line between the tested device and the testing device.

Preferably, the paving size of the paving area and the sub-area is determined according to simulation data of electromagnetic scattering simulation, wherein paving cement treatment is carried out on the area of which the phase and amplitude variation value of the electromagnetic field strength does not exceed 1.5 dB.

Preferably, the ground in the area to be tested is laid by cement.

Preferably, the transition region of the region to be tested comprises two edges, the two edges extend from the boundary of the pit towards each other and meet at the tip, and the two edges form a certain angle with the incoming wave direction of the test equipment.

Preferably, a drainage ditch is arranged in the pit of the measured area.

Preferably, the periphery of the drainage ditch is provided with a laying area made of wave-absorbing materials.

Preferably, a traction channel is arranged in the direction of the measured area away from the transition area, and is used for drawing the measured equipment into the measured area.

The application provides a new outfield target radar cross section test field, saves construction cost greatly, can satisfy the accurate measurement demand of the complete machine radar stealth characteristic of certain type of aircraft after establishing, can provide technical support for aircraft stealth tests such as stealth improved generation of the third generation of aircraft, fourth generation of aircraft simultaneously.

Drawings

Figure 1 is a top view of the outfield RCS test field of the present application.

Fig. 2 is a top plan view of the paved area of the embodiment of the invention shown in fig. 1.

Fig. 3 is a top view of the area under test of the embodiment of fig. 1 of the present application.

The method comprises the following steps of 1-main area, 2-tested equipment, 3-tested equipment, 4-laying area, 41-first expansion section, 42-wide section, 43-second expansion section, 5-auxiliary area, 6-tested area, 61-edge, 62-drainage ditch, 63-wave absorbing material, 64-traction channel and 7-cleaning area.

Detailed Description

In order to make the implementation objects, technical solutions and advantages of the present application clearer, the technical solutions in the embodiments of the present application will be described in more detail below with reference to the accompanying drawings in the embodiments of the present application. In the drawings, the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The described embodiments are some, but not all embodiments of the present application. The embodiments described below with reference to the drawings are exemplary and intended to be used for explaining the present application, and should not be construed as limiting the present application. All other embodiments obtained by a person of ordinary skill in the art without any inventive work based on the embodiments in the present application are within the scope of protection of the present application. Embodiments of the present application will be described in detail below with reference to the drawings.

The application provides an outfield RCS test field, as shown in fig. 1-3, mainly includes:

the test device comprises a main area 1, wherein the main area 1 is a rectangular area located between a tested device 2 and a tested device 3, a laying area 4 is arranged in the main area 1, the laying area forms three laying sections in the direction from the tested device 2 to the tested device 3, and the width of the middle laying section is larger than that of the laying sections at two ends;

a secondary zone 5, the secondary zone 5 surrounding the primary zone 1;

the tested area 6 is used for storing the tested equipment 2, the tested area 6 is arranged to be lower than the ground of the main area 1 in the vertical direction, so that a pit is formed, the pit is in inclined transition towards the main area, and a tip facing the tested equipment 3 is formed in the transition area;

and cement is paved on the ground of the pavement area 4, the sub-area 5 and the tested area 6.

In the embodiment, the auxiliary area 5 further comprises a cleaning area 7, cleaning treatment is carried out on other areas of the main area except the paving area 4 and the cleaning area 7, and the method is based on an integral three-dimensional modeling and electromagnetic simulation method, comprehensively applies measures such as vegetation treatment of surrounding buildings of the site, multipath clutter positioning and elimination and the like to carry out integral control and optimization on the site background, and can effectively solve the problem of high background level of the stealth target test in the complex environment.

In this embodiment, the pit depth is generally set to 0.4m, and a low-scattering stealth design technology is applied to a low-scattering design of a target area, so that the target area is designed to be a pit with a depth of 0.4m, and thus, electromagnetic waves cannot directly irradiate the ground and objects such as wave-absorbing materials laid on the ground, the coupling between a target to be measured and a turntable is effectively reduced, and the background level of the target area is also prevented from being influenced. Designing the side of the pit facing the antenna in a peaked-sloped fashion effectively reduces the scattering effect at the edge of the target area. In the specific embodiment, a ray tracing method is adopted to simulate the electromagnetic wave path of the field, obtain stray electromagnetic wave data and inhibit the stray electromagnetic waves, so that the background level of a test area is lower than-40 dBsm.

The device under test of the present application is an aircraft or an aircraft component.

In some alternative embodiments, the cement has a flatness of less than 2 mm.

In some optional embodiments, as shown in fig. 2, the paving area includes a first expanding section 41, a wide section 42, and a second expanding section 43, where the wide section 42 is located in the middle and has the largest width, the first expanding section 41 and the second expanding section 43 respectively extend from two sides of the wide section to two ends of the paving area 4 in a direction of narrowing in width, tip sections are respectively disposed at ends of the first expanding section 41 and the second expanding section 43, and tips of the two tip sections are located on a connecting line between the device under test 2 and the testing device 3. The tip is designed in the same principle as the tip of the area under test, for reducing the scattering effect of the edge.

In some alternative embodiments, the paving dimensions of the paved area 4 and sub-area 5 are determined according to simulation data of electromagnetic scattering simulation, wherein paving cement treatment is performed on the area with the phase and amplitude variation value of the electromagnetic field strength not exceeding 1.5 dB.

In some alternative embodiments, the ground in the area under test 6 is laid with cement.

In some alternative embodiments, as shown in fig. 3, the transition area of the tested area comprises two edges 61, which extend from the boundary of the pit towards each other and meet at the tip, and which are angled with respect to the incoming wave direction of the test device 3. In this embodiment, the shape of the region to be measured is designed to be a low-scattering hexagon lower than the ground, one surface of the region to be measured, which is close to the antenna (equipment region), is designed to be a sharp-top slope, the ground of the target region is a plane, cement paving is adopted, and the edge forms an oblique line relative to the incoming wave direction of the electromagnetic wave.

In some alternative embodiments, a drain 62 is disposed within the pit of the zone under test.

In some alternative embodiments, the periphery of the drainage ditch is provided with a paved area made of wave-absorbing material 63.

In some alternative embodiments, the direction of the measured area away from the transition area is provided with a traction channel 64 for pulling the device under test 2 from the runway into the measured area.

The application firstly provides a target scattering characteristic outdoor test field construction scheme for local treatment of an electromagnetic wave mirror reflection Fresnel zone, the laying area of a test channel is only 17.15% of that of a standard field, and the construction cost can be greatly reduced while the field performance is ensured.

The above description is only for the specific embodiments of the present application, but the scope of the present application is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present application should be covered within the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. An outfield RCS test field, comprising:

the main area (1) is a rectangular area located between a tested device (2) and a testing device (3), a laying area (4) is arranged in the main area (1), the laying area forms three laying sections along the direction from the tested device (2) to the testing device (3), and the width of the middle laying section is larger than the width of the laying sections at two ends;

a secondary zone (5), the secondary zone (5) surrounding the primary zone (1);

the tested area (6) is used for storing the tested equipment (2), the tested area (6) is arranged to be lower than the ground of the main area (1) in the vertical direction, so that a pit is formed, the pit is in inclined transition towards the main area, and a tip facing the testing equipment (3) is formed in the transition area;

and cement is paved on the ground of the pavement area (4), the auxiliary area (5) and the tested area (6).

2. The outfield RCS test site of claim 1, wherein the cement has an unevenness of less than 2 mm.

3. The outfield RCS test site according to claim 1, wherein the paving area comprises a first expanded section (41), a wide section (42) and a second expanded section (43), wherein the wide section (42) is located in the middle and has the largest width, the first expanded section (41) and the second expanded section (43) respectively extend from two sides of the wide section to two ends of the paving area (4) in a width narrowing trend, tip sections are respectively arranged at the ends of the first expanded section (41) and the second expanded section (43), and the tips of the two tip sections are located on a connecting line between the tested device (2) and the test device (3).

4. Outfield RCS test yard according to claim 1, wherein the dimensions of the paved area (4) and sub-area (5) are determined from simulation data of an electromagnetic scattering simulation, wherein the area having an electromagnetic field strength with a phase and amplitude variation value not exceeding 1.5dB is treated by paving cement.

5. Outfield RCS test site according to claim 1, characterized in that the ground in the area under test (6) is laid with cement.

6. Outfield RCS test site according to claim 1, wherein the transition zone of the area under test comprises two ridges (61) extending from the boundary of the pit towards each other and meeting at the point, the two ridges being angled in the direction of the incoming wave of the test equipment (3).

7. The outfield RCS test yard according to claim 1, wherein a drain (62) is provided in the pit of the area under test.

8. The outfield RCS test yard of claim 7, wherein the drain perimeter is provided with a paved area of wave absorbing material (63).

9. Outfield RCS test site according to claim 1, characterized in that the direction of the tested area away from the transition area is provided with a traction channel (64) for pulling the device under test (2) into the tested area.