CN115295995A

CN115295995A - Broadband circuit of high intermodulation circulator

Info

Publication number: CN115295995A
Application number: CN202210862787.7A
Authority: CN
Inventors: 冉扬洲; 李扬兴; 夏瑞青; 尹久红; 王华伟; 王莉
Original assignee: CETC 9 Research Institute
Current assignee: CETC 9 Research Institute
Priority date: 2022-07-21
Filing date: 2022-07-21
Publication date: 2022-11-04
Anticipated expiration: 2042-07-21
Also published as: CN115295995B

Abstract

The invention discloses a broadband circuit of a high intermodulation circulator, belonging to the technical field of microwave components, wherein the radius of a circulator central junction (501) is set to be larger than that of a substrate (401); the high-resistance wire (503) is equally divided by the input end and the output end (502) of the central junction, and the high-resistance wire (503) is equally divided by the input end and the output end (504) of the circulator; the invention can improve the intermodulation performance of the circulator by more than 20 percent, simultaneously can improve the bandwidth to 20 to 25 percent, and gives consideration to the high intermodulation performance and the wide working bandwidth performance of the circulator; the circuit of the invention has wide application range, can realize broadband matching under the conditions of the central junctions such as the round junction, the triangular junction, the round junction deformed junction and the like, and is suitable for the circulator with the line and the micro-strip circulator.

Description

Broadband circuit of high intermodulation circulator

Technical Field

The invention relates to the technical field of microwave components, in particular to a broadband circuit of a high intermodulation circulator.

Background

The microwave gyromagnetic circulator plays the roles of impedance matching and transceiving duplexing in a microwave circuit system. The circulator structurally comprises a cavity 1, a magnet 2, a magnetic homogenizing sheet 3, a substrate 401, a central conductor 5 (comprising a central junction 501, wherein the radius of the central junction 501 is smaller than that of the substrate 401 in general), a temperature compensating sheet 6, a cover plate 7 and the like; an assembly schematic of a typical circulator is shown in fig. 1, in which a magnet 2 provides a static magnetic field to a substrate 4; the uniform magnetic sheet 3 homogenizes the static magnetic field provided by the magnet 2 and then transmits the homogenized magnetic field to the substrate 401; the magnetized substrate 401 provides a gyromagnetic effect for the circulator; the central conductor 5 is used for transmitting microwave signals; the medium 402 acts to improve circuit matching; the temperature compensation sheet 6 provides wide temperature working capacity for the device; the cover plate 7 and the chamber 1 press all the parts together to form a circulator, as shown in fig. 2.

The circuit of the center conductor 5 of the known circulator is typically an LC matching circuit or a lambda/4 matching circuit. Because the bandwidth design of the circulator and the intermodulation performance design conflict with each other, the two are in a negative correlation relationship. The concrete points are as follows: the bandwidth of the circulator is often narrow when the intermodulation performance of the circulator is good, and the intermodulation performance of the circulator is poor when the bandwidth is wide.

Therefore, how to provide a circulator with wider bandwidth and better intermodulation performance is a technical problem which needs to be solved urgently in the field.

Disclosure of Invention

The present invention aims to provide a wideband circuit of a high intermodulation circulator, so as to solve the above problems.

In order to achieve the purpose, the technical scheme adopted by the invention is as follows: a broadband circuit of a high intermodulation circulator, the circulator comprises a substrate, a medium, a central conductor and a circuit thereof, the circuit of the central conductor comprises a central junction, a central junction input and output end, a high resistance wire and a circulator input and output end, wherein the radius of the central junction is larger than that of the substrate; the high-resistance lines are evenly divided by the input end and the output end of the central junction, and the high-resistance lines are evenly divided by the input end and the output end of the circulator, namely the input end and the output end of the three central junctions are evenly distributed at 120 degrees.

The invention adopts the proposal that the radius of the central junction is larger than that of the substrate, so that the substrate is positioned in the continuous structure of the central conductor, the current density on the surface of the substrate is reduced, and the intermodulation performance of the circulator is improved.

As a preferable technical scheme: the radius of the central junction is smaller than the radius of the medium. Although the current density on the surface of the medium is not reduced by the structure, the level contribution of the medium to intermodulation is little, and the intermodulation performance of the circulator is not deteriorated.

It should be noted that, in order to adopt a scheme in which the radius of the central junction is larger than that of the substrate, the radius of the central junction is smaller than that of the medium (air and medium), which is a necessary result; but it does not degrade the intermodulation performance of the circulator.

As a preferred technical scheme: the central junction is connected with a high-resistance wire through the input end and the output end of the central junction, and the high-resistance wire is connected with the input end and the output end of the circulator. Electromagnetic energy reaches the high-resistance line from the input end and the output end of the central junction, and reaches the input end and the output end of the circulator through a certain transmission wavelength, so that the electromagnetic wave energy is recombined at the connection position of the high-resistance line and the input end and the output end of the circulator, and the phase is matched at the position, thereby further improving the bandwidth of the circulator.

As a preferable technical scheme: the central knot is a round knot, a triangular knot or a round knot deformed knot. Namely, the circuit is not limited to a round junction, and can still realize broadband matching under the conditions of a triangular junction, a round junction deformed junction and other central junctions; the simulation model of the circuit applied to the triangular junction circulator is shown in fig. 10, and the simulation result of the circuit applied to the triangular junction circulator is shown in fig. 11; the simulation model of the circuit applied to the round junction deformed circulator is shown in fig. 12, and the simulation result of the circuit applied to the round junction deformed circulator is shown in fig. 13.

As a preferred technical scheme: the circulator is a circulator with a line or a micro-strip circulator. Namely, the wideband circuit of the patent is not limited to the design of promoting the intermodulation of the circulator, is not limited to being suitable for the circulator with the strip line, and is still suitable for the design of the microstrip circulator, the simulation model of the microstrip circulator adopting the wideband circuit of the patent is shown as figure 8, and the simulation result is shown as figure 9.

Compared with the prior art, the invention has the advantages that: the invention can improve the intermodulation performance of the circulator by more than 20 percent, simultaneously can improve the bandwidth to 20 to 25 percent, and considers the high intermodulation performance and the wide working bandwidth performance of the circulator; besides, the circuit of the invention has wide application range, can realize broadband matching under the conditions of the central junctions such as the round junction, the triangular junction, the round junction deformed junction and the like, and is suitable for a circulator with a line and a micro-strip circulator.

Drawings

FIG. 1 is a schematic view of an assembly of typical circulator components;

FIG. 2 is a schematic diagram of a typical circulator;

fig. 3 is a simulation model of an LC matching circuit of a high intermodulation circulator according to an embodiment of the present invention;

fig. 4 is a simulation result of the LC matching circuit of the high intermodulation circulator;

fig. 5 is a structure diagram of a wideband circuit of a circulator with lines according to embodiment 1 of the present invention;

FIG. 6 is a simulation model of the circuit of FIG. 5 applied to improve the intermodulation performance of a circulator;

FIG. 7 is a simulation result of the circuit of FIG. 5 applied to improve the performance of the circulator;

FIG. 8 is a simulation model of the circuit of FIG. 5 applied to a microstrip circulator;

FIG. 9 shows simulation results of the circuit of FIG. 5 applied to a microstrip circulator;

FIG. 10 is a simulation model of the circuit of the present invention applied to a triangular junction circulator;

FIG. 11 shows the simulation result of the circuit of the present invention applied to a triangular junction circulator;

FIG. 12 is a simulation model of the circuit of the present invention applied to a round junction deformed junction circulator;

fig. 13 shows the simulation result of the circuit of the present invention applied to the circular junction transformer circulator.

In the figure: 1. a cavity; 2. a magnet; 3. homogenizing magnetic sheets; 401. a substrate; 402. a medium; 5. a center conductor; 501. a central knot; 502. a central junction input and output end; 503. a high resistance wire is connected; 504. input and output ends of the circulator; 6. a temperature compensation sheet; 7. and (7) a cover plate.

Detailed Description

The invention will be further explained with reference to the drawings.

Example 1:

a broadband circuit of a high intermodulation circulator, as shown in FIG. 5, the circulator is a strip-line circulator, which includes a substrate 401, a medium 402, a central conductor 5 and its circuit, in this embodiment, the circuit of the central conductor 5 is a round junction circuit, which includes a central junction 501, a central junction input/output terminal 502, a high resistance line 503 and a circulator input/output terminal 504, wherein the radius of the central junction 501 is larger than that of the substrate 401, as shown in FIG. 3, so that the substrate 401 is in a continuous structure of the central conductor 5, the current density on the surface of the substrate 401 is reduced, and the intermodulation performance of the circulator is improved; the radius of the central junction 501 is smaller than that of the medium 402, the high-resistance line 503 is equally divided by the input and output ends 502 of the central junction, and the high-resistance line 503 is equally divided by the input and output ends 504 of the circulator;

the central junction 501 is connected with a high-resistance line 503 through a central junction input and output end 502, and the high-resistance line 503 is connected with a circulator input and output end 504;

electromagnetic energy reaches the high resistance wire 503 from the central junction input-output end 502, and reaches the circulator input-output end 504 through a certain transmission wavelength, so that the electromagnetic wave energy is recombined at the connection position of the high resistance wire 503 and the circulator input-output end 504, and the phase is matched at the position, thereby improving the bandwidth of the circulator;

in order to improve the intermodulation performance of the circulator, the present embodiment adopts a technical path in which the radius of the central junction 501 of the central conductor 5 is larger than that of the substrate 401. However, the circuit of the existing circulator is generally an LC matching circuit or a λ/4 matching circuit, the bandwidth under the technical path is generally 5% to 15%, the simulation model of the center conductor being the LC matching circuit is shown in fig. 3, the simulation result is shown in fig. 4, and it can be known from the simulation result that the bandwidth is only 14.6%.

The invention has two improvement points, one is structural improvement, see the simulation model of fig. 3, which is used for improving the intermodulation of the circulator, and the other is a broadband matching circuit, see fig. 5, which is used for improving the bandwidth; the two invention points can exist independently, and the two invention points are organically combined in the embodiment, so that the bandwidth is improved while the intermodulation performance is improved by the circulator.

A simulation model of the circuit applied to the circulator of the embodiment is shown in fig. 6, a simulation result of the circuit is shown in fig. 7, an actually measured intermodulation performance of an original circulator is about-72 dBc (third order intermodulation performance of the actually measured circulator), an actually measured intermodulation performance of the circulator designed by the circuit of the embodiment is about-89 dBc, and the circuit of the embodiment can improve the intermodulation performance of the circulator by more than 20%; the comparison of simulation results shows that the bandwidth is increased to 20% -25% in the embodiment.

The above description is intended to be illustrative of the preferred embodiment of the present invention and should not be taken as limiting the invention, but rather, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.

Claims

1. A wideband circuit for a high intermodulation circulator comprising a substrate (401), a dielectric (402) and a center conductor (5) and circuitry thereof, characterized in that: the circuit of the central conductor (5) comprises a central junction (501), a central junction input and output end (502), a high-resistance wire (503) and a circulator input and output end (504), wherein the radius of the central junction (501) is larger than that of the substrate (401); the high-resistance lines (503) are equally divided by the input end and the output end (502) of the central junction, and the high-resistance lines (503) are equally divided by the input end and the output end (504) of the circulator.

2. The wideband circuit of a high intermodulation circulator as recited in claim 1, wherein: the radius of the central junction (501) is smaller than the radius of the medium (402).

3. The wideband circuit for a high intermodulation circulator as recited in claim 1, wherein: the central junction (501) is connected with a high-resistance wire (503) through a central junction input-output end (502), and the high-resistance wire (503) is connected with a circulator input-output end (504).

4. The wideband circuit of a high intermodulation circulator as recited in claim 1, wherein: the central knot (501) is a round knot, a triangular knot or a round knot deformed knot.

5. The wideband circuit of a high intermodulation circulator as recited in claim 1, wherein: the circulator is a circulator with a line or a micro-strip circulator.