CN207338586U - A kind of S/C wave bands passband adjustable type frequency selecting structures - Google Patents

Abstract

The utility model discloses an adjustable S/C band passband frequency selection structure, which comprises an intermediate medium layer, a first metal layer located on the upper surface of the intermediate medium layer and a second metal layer located on the lower surface of the intermediate medium layer. The S/C band passband adjustable frequency selection structure described in the utility model has the characteristics of adjustable passband number, fine-tuning of passband performance, high passband selectivity, large passband span, good stability and simple adjustment , realizing reconfigurable multifunctional applications of band-pass filtering while keeping the periodic structure unchanged.

Description

A frequency selection structure with adjustable passband in S/C band

technical field

The utility model relates to the technical field of electromagnetic fields and microwaves, in particular to the structure of a frequency selection surface capable of realizing adjustable passbands in S-band and C-band.

Background technique

A frequency selective surface (FSS) is a single-screen or multi-screen periodic array structure composed of a large number of passive resonant units, which is composed of periodically arranged metal patch units or periodically arranged aperture units on a metal screen. This surface can be totally reflective (patch type) or fully transmissive (aperture type) near the cell's resonant frequency.

As a spatial filter, the frequency selective structure is widely used. For example, as a secondary reflector in satellite communications, it can effectively improve system utilization; as a radome in fighter jets, it can reduce the radar cross section of the antenna. With the development of the frequency selection structure, the required center frequency of the passband will also increase, which will lead to a rapid increase in the insertion loss in the passband, which will deteriorate the passband characteristics of the frequency selection structure.

Utility model content

Aiming at the above problems, the utility model proposes an S/C band passband adjustable frequency selection structure, which has the advantages of high passband selectivity, low insertion loss and high stability.

The technical means adopted in the utility model are as follows:

An S/C band passband adjustable frequency selection structure, comprising an intermediate dielectric layer, a first metal layer located on the upper surface of the intermediate dielectric layer, and a second metal layer located on the lower surface of the intermediate dielectric layer; the first metal layer It includes four first bending units, second bending units, third bending units and fourth bending units with the same shape, the four bending units are center-symmetrical to the center of the first metal layer, and each bending The positional relationship between the folding units is 90° around the center of symmetry, and the bending units include the first branch, the second branch, the third branch, the fourth branch, the fifth branch, the sixth branch, and the seventh branch And the eighth branch, the first branch and the third branch are arranged in parallel and perpendicular to the second branch, and the second branch is connected to one end of the first branch and the third branch, so The fourth branch is vertically connected to the other end of the third branch, the fifth branch is connected to the other end of the fourth branch and parallel to the first branch, and the sixth branch is connected to the The other end of the fifth branch is parallel to the fourth branch, the seventh branch is connected to the other end of the sixth branch and parallel to the first branch, and the eighth branch is connected to the seventh branch. The other end of the branch is parallel to the fourth branch, and the other end of the eighth branch of the four bending units is connected at the center of the first metal layer; the second metal layer includes four groups of The first corner patch group, the second corner patch group, the third corner patch group and the fourth corner patch group, the corner patch groups are respectively placed at the four corners of the lower surface of the intermediate medium layer, The corner patch group includes a first square patch, a first L-shaped patch and a second L-shaped patch, and the first square patch, the first L-shaped patch and the second L-shaped patch The second metal layer also includes a cross patch placed at the center of the lower surface of the intermediate dielectric layer and a first long patch on the extension line of the four sides of the cross patch. a strip patch, a second strip patch, a third strip patch and a fourth strip patch, the first strip patch and one side of the corresponding cross patch are loaded with the first strip patch A lumped inductance, a second lumped inductance is loaded between the second strip patch and one side of the cross patch corresponding to it, the third strip patch and the corresponding cross patch A first lumped capacitance is loaded between one side of the cross patch, and a second lumped capacitance is loaded between the fourth strip patch and one side of the corresponding cross patch;

Further, the first lumped inductance, the second lumped inductance, the first lumped capacitor and the second lumped capacitor are detachably fixed on the second metal layer;

Further, the widths of the first branch, the second branch and the third branch are the same, the width of the fourth branch is larger than the width of the first branch, the second branch and the third branch, and the The widths of the fifth branch, sixth branch, seventh branch and eighth branch decrease successively;

Further, the widths of the first square patch, the first L-shaped patch and the second L-shaped patch decrease sequentially, and the gap between the first square patch and the first L-shaped patch greater than the gap between the first L-shaped patch and the second L-shaped patch.

Compared with the prior art, the S/C band passband adjustable frequency selection structure described in the utility model has the following advantages:

1. The S/C band passband adjustable frequency selection structure adopts a bimetallic structure to achieve stable dual passband transmission within the working frequency, which is convenient for parameter adjustment when the frequency changes;

2. The first metal layer and the second metal layer of the S/C band passband adjustable frequency selection structure respectively adopt a centrosymmetric structure, which can have good transmission stability when inputting different incident waves at large angles ;

3. The S/C band passband adjustable frequency selection structure integrates lumped inductance and lumped capacitance on the second metal layer, and the lumped inductance and lumped capacitance are detachably fixed on it, which is convenient for corresponding parameters adjustment, which improves the reconfigurability of the bandpass filter.

Description of drawings

Fig. 1 is the exploded view of the three-dimensional structure of the S/C band passband adjustable frequency selection structure of the utility model;

Fig. 2 is the structural view of the first metal layer of the S/C band passband adjustable frequency selection structure of the utility model;

Fig. 3 is the structural view of the second metal layer of the S/C band passband adjustable frequency selection structure of the present invention;

Fig. 4 is a structural view of the bending unit of the S/C band passband adjustable frequency selection structure of the utility model;

In the figure: 1, the first metal layer;

11. The first bending unit, 12. The second bending unit, 13. The third bending unit, 14. The fourth bending unit;

111, the first branch, 112, the second branch, 113, the third branch, 114, the fourth branch, 115, the fifth branch, 116, the sixth branch, 117, the seventh branch, 118, the eighth branch;

2. The second metal layer;

21. First corner patch group, 22. Second corner patch group, 23. Third corner patch group, 24. Fourth corner patch group, 25. Cross patch, 26. First lumped inductance, 27 , the second lumped inductance, 28, the first lumped capacitance, 29, the second lumped capacitance;

211, the first square patch, 212, the first L-shaped patch, 213, the second L-shaped patch, 214, the first long patch, 215, the second long patch, 216, the third long patch Strip patch, 217, the fourth strip patch;

3. Intermediate medium layer.

Detailed ways

As shown in Fig. 1, Fig. 2, Fig. 3 and Fig. 4, an S/C band passband adjustable frequency selection structure includes an intermediate dielectric layer 3, a first metal layer 1 located on the upper surface of the intermediate dielectric layer 3, and The second metal layer 2 located on the lower surface of the intermediate dielectric layer 3; the first metal layer 1 includes four first bending units 11, second bending units 12, third bending units 13 and fourth bending units with the same shape. Bending unit 14, the four bending units are center-symmetrical to the center of the first metal layer 1, and the positional relationship between each bending unit is 90° around the center of symmetry, and the bending unit includes a first branch 111, the second branch 112, the third branch 113, the fourth branch 114, the fifth branch 115, the sixth branch 116, the seventh branch 117 and the eighth branch 118, the first branch 111, the third branch The nodes 113 are arranged in parallel and perpendicular to the second branch 112, the second branch 112 is connected to one end of the first branch 111 and the third branch 113, and the fourth branch 114 is vertically connected to the The other end of the third branch 113, the fifth branch 115 is connected to the other end of the fourth branch 114 and parallel to the first branch 111, the sixth branch 116 is connected to the fifth branch 115 and parallel to the fourth branch 114, the seventh branch 117 is connected to the other end of the sixth branch 116 and parallel to the first branch 111, the eighth branch 118 is connected to the The other end of the seventh branch 117 is parallel to the fourth branch 114, the other end of the eighth branch 118 of the four bending units is connected at the center of the first metal layer 1; the second metal layer 2 includes four sets of the first corner patch group 21, the second corner patch group 22, the third corner patch group 23 and the fourth corner patch group 24 with the same structure, and the corner patch groups are respectively placed in the middle At the four corners of the lower surface of the dielectric layer 3, the corner patch group includes a first square patch 211, a first L-shaped patch 212 and a second L-shaped patch 213, and the first square patch The sheet 211, the first L-shaped patch 212, and the second L-shaped patch 213 are arranged at a certain interval from the corner to the center, and the second metal layer 2 also includes a The cross patch 25 and the first strip patch 214, the second strip patch 215, the third strip patch 216 and the fourth strip patch 217 on the extension line of the four sides of the cross patch 25 , the first lumped inductance 26 is loaded between the first strip patch 214 and one side of the cross patch 25 corresponding thereto, the second strip patch 215 and the corresponding cross patch 25 A second lumped inductance 27 is loaded between one side of the cross patch 25, and a first lumped capacitance 28 is loaded between the third strip patch 216 and the corresponding side of the cross patch 25, A second lumped capacitor 29 is loaded between the fourth strip patch 217 and one side of the corresponding cross patch 25 .

Further, the first lumped inductance 26, the second lumped inductance 27, the first lumped capacitor 28, and the second lumped capacitor 29 are detachably fixed on the second metal layer 2. In this optional structure When adjusting the number of band pass and band stop, it can be adjusted by changing the numerical value of each lumped element.

Further, the width of the first branch 111, the second branch 112 and the third branch 113 is the same, and the width of the fourth branch 114 is larger than that of the first branch 111, the second branch 112 and the third branch. The width of the node 113, the widths of the fifth branch 115, the sixth branch 116, the seventh branch 117 and the eighth branch 118 decrease in sequence.

Further, the widths of the first square patch 211, the first L-shaped patch 212, and the second L-shaped patch 213 decrease sequentially, and the first square patch 211 and the first L-shaped patch The gap between 212 is larger than the gap between the first L-shaped patch 212 and the second L-shaped patch 213 .

Example

According to the actual project requirements, this example provides a multi-band adjustable frequency selection structure that works in the 8GHz range and forms multiple stable passbands at 1.1GHz, 3.2GHz, 4.5GHz and 7.5GHz respectively.

Test data for transmittance of selected structures represented in Table 1

0° incident 30° incident 45° incident 60° incident mean shift center frequency 1 1.1GHz 1.1GHz 1.1GHz 1.1GHz --------- center frequency 2 3.2GHz 3.2GHz 3.2GHz 3.2GHz --------- Center frequency 3 4.5GHz 4.5GHz 4.5GHz 4.5GHz --------- Center frequency 4 7.5GHz 7.5GHz 7.5GHz 7.5GHz --------- Passband 1 Width 1.4GHz 1.41GHz 1.35GHz 1.29GHz 3.1% Transmission Zero 1 3.05GHz 3.06GHz 3.10GHz 3.05Hz 0.1% Passband 2 width 0.4GHz 0.41GHz 0.35GHz 0.29GHz 3.1% Transmission Zero 2 3.95GHz 3.95GHz 3.95GHz 3.95GHz --------- Passband 3 width 0.61GHz 0.63GHz 0.67GHz 0.65GHz 1.2% Transmission Zero 3 5.42GHz 5.45GHz 5.43GHz 5.43Hz 0.5% Passband 4 width 1.4GHz 1.41GHz 1.35GHz 1.29GHz 3.1% Transmission Zero 4 8.05GHz 8.06GHz 7.98GHz 7.99Hz 0.1%

It can be seen from the table that the selected structure can be used for electromagnetic waves with center frequencies of 1.1GHz, 3.2GHz, 4.5GHz and 7.5GHz and incident angles of 0°, 30°, 45° and 60°. Good transmission, so the selected structure has the advantages of good stability and large passband span.

The above is only a preferred embodiment of the utility model, but the scope of protection of the utility model is not limited thereto. Any equivalent replacement or change of the new technical solution and its inventive concept shall be covered by the protection scope of the present utility model.

Claims (4)

1. A S/C band passband adjustable frequency selection structure, characterized in that: comprising an intermediate dielectric layer, a first metal layer positioned on the upper surface of the intermediate dielectric layer and a second metal layer positioned on the lower surface of the intermediate dielectric layer; The first metal layer includes four first bending units, a second bending unit, a third bending unit and a fourth bending unit with the same shape, and the four bending units are formed in the center of the first metal layer. The center is symmetrical, and the positional relationship between each bending unit is 90° around the center of symmetry. The bending unit includes the first branch, the second branch, the third branch, the fourth branch, the fifth branch, the first The six branches, the seventh branch and the eighth branch, the first branch and the third branch are arranged in parallel and perpendicular to the second branch, and the second branch is connected between the first branch and the third branch. One end of the branch, the fourth branch is vertically connected to the other end of the third branch, the fifth branch is connected to the other end of the fourth branch and is parallel to the first branch, the The sixth branch is connected to the other end of the fifth branch and parallel to the fourth branch, the seventh branch is connected to the other end of the sixth branch and parallel to the first branch, and the eighth branch is connected to the other end of the sixth branch and parallel to the first branch. connected to the other end of the seventh branch and parallel to the fourth branch, the other end of the eighth branch of the four bending units is connected at the center of the first metal layer; The second metal layer includes four sets of the first corner patch group, the second corner patch group, the third corner patch group and the fourth corner patch group with the same structure, and the corner patch groups are respectively placed on the At the four corners of the lower surface of the intermediate medium layer, the corner patch group includes a first square patch, a first L-shaped patch and a second L-shaped patch, the first square patch, the second L-shaped patch An L-shaped patch and a second L-shaped patch are sequentially arranged with a certain gap from the corner to the center, and the second metal layer also includes a cross patch placed at the center of the lower surface of the intermediate dielectric layer and a cross patch at the center of the cross The first long patch, the second long patch, the third long patch and the fourth long patch on the extension line of the four sides of the patch, the first long patch and its corresponding A first lumped inductance is loaded between one side of the cross patch, a second lumped inductance is loaded between the second strip patch and one side of the corresponding cross patch, and the first A first lumped capacitor is loaded between the three strip patches and one side of the corresponding cross patch, and a load is loaded between the fourth strip patch and one side of the corresponding cross patch. There is a second lumped capacitor. 2. The S/C band passband adjustable frequency selection structure according to claim 1, characterized in that: the first lumped inductance, the second lumped inductance, the first lumped capacitor and the second lumped The capacitor is detachably fixed on the second metal layer. 3. The S/C band passband adjustable frequency selection structure according to claim 1 or 2, characterized in that: the widths of the first branch, the second branch and the third branch are the same, and the first branch The widths of the four branches are greater than the widths of the first branch, the second branch and the third branch, and the widths of the fifth branch, the sixth branch, the seventh branch and the eighth branch decrease in sequence. 4. The S/C band passband adjustable frequency selection structure according to claim 3, characterized in that: the width of the first square patch, the first L-shaped patch and the second L-shaped patch Decreasing in order, the gap between the first square patch and the first L-shaped patch is larger than the gap between the first L-shaped patch and the second L-shaped patch.