CN113161724A

CN113161724A - Compact range multi-feed source rotary table

Info

Publication number: CN113161724A
Application number: CN202011275998.8A
Authority: CN
Inventors: 邓晖; 刘子雄
Original assignee: Beihang University
Current assignee: Beihang University
Priority date: 2020-11-13
Filing date: 2020-11-13
Publication date: 2021-07-23
Anticipated expiration: 2040-11-13
Also published as: CN113161724B

Abstract

The invention relates to the field of compact range feed sources, and provides a low-frequency low-scattering feed source rotary table structure which comprises an irregular polygonal rotary table which is vertically arranged, wherein an inclined mounting plate is arranged on the edge of the rotary table, feed sources with different sizes can be mounted on the mounting plate, and the structure can realize the sharing of multiple feed sources and low-frequency low-scattering according to the required actual requirements.

Description

Compact range multi-feed source rotary table

Technical Field

The invention relates to the field of compact range feed sources, in particular to a compact range feed source rotary table structure with low scattering at low frequency and multiple feed sources.

Background

Because the feed sources adopted by the compact range in different frequency bands are different, the feed sources are required to be replaced before the compact range is switched to the working frequency band. The position and angle of the feed source are adjusted after the feed source is replaced every time, so that the phase center of the single feed source and the phase center of the double feed source are ensured to be positioned at the focus of the reflecting surface, and meanwhile, the performance index balance of the horizontal line and the vertical line of the quiet zone is ensured to achieve the best quality of the quiet zone. Therefore, the feed source rotary table is added in a compact range, and the automatic switching of the feed source is very practical when the working frequency band is changed.

However, the influence of the turntable on the performance of the compact range is inevitably generated, and through analysis and discussion of the influence caused by the feeding turntable in the compact range, an optimal feeding turntable form is required to be searched so as to minimize the influence of the feeding turntable on a dead zone. Meanwhile, when the working frequency is reduced to a low frequency band, the diffraction phenomenon of electromagnetic waves is enhanced, and creeping waves are generated on the rotary table near the feed source to generate more serious interference on a quiet area than a conventional frequency band, so that how to achieve low frequency optimization is also an important problem to be considered in the design of the rotary table.

Disclosure of Invention

In order to solve the problems in the prior art, the invention provides a compact range feed source rotary table structure which has low scattering at low frequency and is shared by a plurality of feed sources. The rotary disc is provided with an inclined mounting plate and rotates in the vertical direction to realize the switching of the feed source. The inclination angle of each mounting plate on the rotary table (namely the included angle between the mounting plate and the extension plate of the vertical flat plate in the middle of the rotary table) is the elevation angle of the feed source. The width of each mounting plate is determined by the size of the feed source pair mounted on the mounting plate and the maximum spacing distance between the feed source pairs, the different widths of the mounting plates enable more pairs of feed sources to be mounted on the rotary table with the same size, and meanwhile, the feed sources in the same layout are far away from the rotary table as far as possible to weaken the irradiation of the rotary table by the working feed sources. Because the distances from the lower edges of the mounting plates to the rotating center of the turntable are different, the length of each mounting plate is ensured that the phase center of the feed source mounted on the mounting plate falls on the focal point of the reflecting surface.

Preferably, the feed source axis of the turntable structure should be perpendicular to the mounting plate, so to ensure that the phase center of the feed source is on the focus (the phase center of the feed source in a pair is on the left and right sides of the focus, and the focus is on the connecting line of the two phase centers), the intersection point of the feed source axis and the corresponding mounting plate must be on a straight line parallel to the long side of the mounting plate, which is referred to as the "alignment line" of each mounting plate. The black line shown in fig. 2 is the alignment line of the mounting board, the axes of all the feed sources to be mounted on the mounting board are perpendicular to the mounting board, and the intersection point falls on the line.

Since the floor of the vertical turntable is an irregular polygon, the number of sides of the vertical turntable can be determined according to the specific embodiment.

Preferably, the axis of the feed of the turret structure is perpendicular to the mounting plate and the focal point is parallel to the "alignment line", and the length of the long side of the mounting plate is determined by the maximum separation distance between the feeds mounted in pairs and the diameter of the flange, irrespective of the slack length, the former being determined by the frequency of the paired feeds used. After the length of the long side is determined, the circumscribed circle of the irregular polygon can be determined, and then the irregular polygon base plate is determined.

Because the elevation angle of the feed source is determined by the position of the reflecting surface, the intersection point position of the alignment line and the short side can be determined according to the geometric relation under the condition, and the length of the short side of the mounting plate is determined without considering the surplus length according to the radius of the flange plate.

Preferably, in order to install different feed sources on the same mounting plate conveniently, a slide rail can be arranged on the alignment line, and the length of the long edge of the mounting plate is determined by the feed source with the lowest frequency.

Because the indoor space in a dark room of a compact range is limited, the vertical distance from the focal point of a reflecting surface to the ground is limited to a certain range, so the energy of the irradiation of the working feed source to the surrounding non-working feed source is required to be as low as possible so as to reduce the scattering of the non-working feed source to a dead zone. Preferably, two methods of oppositely placing two feed sources in the lowest frequency band and determining the length of the mounting plate according to the sizes of the feed sources are adopted. Because the feeds in the low frequency band tend to have wider main lobe widths and larger sizes, the two feeds at the lowest end can be oppositely arranged to be farthest away so as to weaken mutual irradiation between the two feeds. Meanwhile, the length of each corresponding mounting plate is determined according to the size of the feed source, so that the distance between the low-frequency-band large feed source and the peripheral feed source is farther, the higher utilization rate of the feed source rotary table can be achieved, and the sizes of the rotary tables of the feed sources with the same number and the same frequency bands which can be arranged are made to be as small as possible.

Drawings

FIG. 1 is a schematic view of a novel vertical rotary table with 8 mounting plates

FIG. 2 is a schematic view of the alignment of the mounting plate

FIG. 3 shows a new vertical turntable layout for a common large reflector compact range system

FIG. 4a is a schematic view of a novel vertical rotary table with 5 mounting plates and 5 cylindrical feed pairs

FIG. 4b is another schematic view of the novel vertical rotary table with 5 mounting plates and 5 cylindrical feed pairs

FIG. 4c is another schematic view of the novel vertical rotary table with 5 mounting plates with 5 cylindrical feed pairs mounted thereon

FIG. 5a is a schematic view of a novel vertical rotary table with 5 mounting plates, which is provided with a 1-pyramid feed source and a 4-pyramid feed source

FIG. 5b is another schematic view of the novel vertical rotary table with 5 mounting plates and 1 pyramid feed source and 4 pyramid feed sources

FIG. 5c is another schematic diagram of the novel vertical rotary table with 5 mounting plates and 1 pyramid feed source and 4 pyramid feed sources

Detailed Description

The present invention will be described in detail below with reference to the accompanying drawings.

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific examples described herein are intended to be illustrative only and are not intended to be limiting.

Example (b): as shown in fig. 4a-c and fig. 5a-c, the present embodiment provides a novel vertical rotary table with 5 mounting plates, where the mounting plate on the rotary table is started from the top (the longest mounting plate), and is sequentially marked as "one", "five", and "five", clockwise, the cylindrical feeds are numbered according to size, and are sequentially marked as "mark (r)" to "mark (r") from large to small, the pyramidal feeds are numbered according to size, and are sequentially marked as "width 1" to "width 5" from large to small, where except that "width 1" and "width 2" are single feeds, all other feeds are installed in pairs. For example, a "one," number mounting plate, the feeds that are intended to be installed interchangeably are: nominally, wide 1 and wide 2. Where Width 1 and Width 2 are single, their centers should be at the location of the focal point; the index is one pair, and the position of the focus is at the midpoint of the connecting line of the centers of the two feeds. When the feed source is installed, the axis of the feed source is perpendicular to the installation plate, so in order to ensure that the phase center of the feed source is on the focus (the phase center of the feed source in a pair is on the left side and the right side of the focus, and the focus is on the connecting line of the two phase centers), the intersection point of the axis of the feed source and the corresponding installation plate is always on a straight line parallel to the long edge of the installation plate.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.

Claims

1. A reflecting surface compact range feed source rotary table structure is characterized in that the reflecting surface compact range feed source rotary table structure is vertically placed, a mounting plate is installed on the outer side of a rotary table, a rotary table base is a polygonal rotary table, a feed source is installed on an inclined plate, and scattering to a quiet area is low when the frequency is low.

2. A turntable structure as claimed in claim 1, wherein the mounting plate is angled such that it is angled with respect to an extension of the central vertically oriented plate of the turntable.

3. Turntable structure as claimed in claim 2, characterized in that the inclination of the mounting plate is the elevation of the feed source.

4. A turntable structure as claimed in claim 1, wherein the side of the mounting plate to which the turntable is attached and the side of the turntable are of equal length.

5. A turret structure according to claim 4, wherein the length of the side of the mounting plate is determined by the size of the pair of mounting feeds and the maximum separation distance between the pairs of feeds.

6. Turntable structure as claimed in claim 1, characterized in that the turntable is an irregular polygon.

7. A turntable structure as claimed in claim 1, wherein the feed source is mounted at its lower end by means of a flange and a support of corresponding height.

8. Turntable structure as claimed in claim 7, characterized in that the height of the supports is such that the phase center of the single feed and the phase center of the double feed lie at the focal point of the reflecting surface.

9. A turret structure according to claim 1, wherein the feeds mounted on the mounting plate may be a single feed or a pair of feeds.

10. A turret structure according to claim 9, wherein the intersection of the feed axis of a feed pair on a mounting plate with the corresponding mounting plate must lie on a line parallel to the long side of the mounting plate.