阅读说明：本技术 一种具有宽带深隔离度的宽带等功率分配/合成电路拓扑 (Broadband equal-power distribution/synthesis circuit topology with broadband deep isolation ) 是由 施永荣 吴启晖 冯文杰 于 2020-12-31 设计创作，主要内容包括：一种具有宽带深隔离度的宽带等功率分配/合成电路拓扑,通过同时引入多模谐振器和宽带复隔离阻抗实现。该等功率分配/合成电路拓扑在经典威尔金森等功率分配/合成电路拓扑基础上,将其四分之一阻抗变换线替换成多模谐振器,该多模谐振器输入输出通过强耦合馈线技术实现；同时将隔离纯电阻替换成宽带复隔离阻抗,该复隔离阻抗则通过特定传输线网络和纯电阻实现；最终本发明公开的等功率分配/合成电路拓扑具有宽带功分/合成、低输入输出驻波和宽带深输出隔离功能。基于本发明公开的等功率分配/合成电路拓扑,可以通过普通微带传输线、悬置微带传输线、带状线传输线、脊间隙波导传输线等支持TEM波/准TEM波的传输线结合表贴电阻实现。(A broadband equipower distribution/synthesis circuit topology with broadband deep isolation is realized by simultaneously introducing a multimode resonator and broadband complex isolation impedance. The power distribution/synthesis circuit topology is based on the classical Wilkinson equal power distribution/synthesis circuit topology, one fourth of the impedance transformation line is replaced by a multimode resonator, and the input and the output of the multimode resonator are realized by a strong coupling feeder line technology; meanwhile, the isolation pure resistor is replaced by a broadband complex isolation impedance, and the complex isolation impedance is realized through a specific transmission line network and a pure resistor; finally, the equal-power distribution/synthesis circuit topology disclosed by the invention has the functions of broadband power distribution/synthesis, low input and output standing waves and broadband deep output isolation. Based on the equipower distribution/synthesis circuit topology disclosed by the invention, the circuit topology can be realized by combining transmission lines supporting TEM waves/quasi-TEM waves such as a common microstrip transmission line, a suspended microstrip transmission line, a strip line transmission line, a ridge gap waveguide transmission line and the like with surface-mounted resistors.)

1. A broadband equal power splitting/combining circuit topology having broadband deep isolation, the circuit topology having axial symmetry, comprising: the broadband multi-mode resonator comprises a common port (1), two first strong coupling feeders (2), two multi-mode resonators (3), two second strong coupling feeders (4), broadband complex isolation impedance (5) and two distribution/synthesis ports (6); the common port (1) is connected to two distribution/synthesis ports (6) through two paths with the same structure, in each path, the common port (1), the first strong coupling feeder line (2), the multimode resonator (3), the second strong coupling feeder line (4) and the distribution/synthesis ports (6) are connected in sequence, and the broadband complex isolation impedance (5) is connected between the two multimode resonators (3).

2. A wideband equal power splitting/combining circuit topology with wideband depth isolation as claimed in claim 1, characterized by: in each path, the first strong coupling feeder line (2) adopts a first coupling transmission line (7), the second strong coupling feeder line (4) adopts a second coupling transmission line (9), half of the first coupling transmission line (7) and half of the second coupling transmission line (9) are both connected with the first transmission line (8), and the multi-mode resonator (3) is realized through a branch line technology.

3. A wideband equal power splitting/combining circuit topology with wideband depth isolation as claimed in claim 2, characterized by: the even-mode characteristic impedance, the odd-mode characteristic impedance and the electrical length of the first coupling transmission line (7) are respectively Z_e1＝150Ω，Z_o1＝30Ω，θ_c190 °; the even-mode characteristic impedance, the odd-mode characteristic impedance and the electrical length of the second coupling transmission line (9) are respectively Z_e2＝100Ω，Z_o2＝9Ω，θ_c290 °; the characteristic impedance and the electrical length of the first transmission line (8) are respectively Z_b＝200Ω，θ_b＝5°。

4. A wideband equal power splitting/combining circuit topology with wideband depth isolation as claimed in claim 2, characterized by: the broadband complex isolation impedance (5) consists of a second transmission line (10), a third transmission line (10 '), a fourth transmission line (11), a fifth transmission line (11 '), a sixth transmission line (12), a seventh transmission line (12 ') and a resistor (13); one end of the second transmission line (10) is connected with one of the first transmission lines (8), the other end of the second transmission line is respectively connected with a fourth transmission line (11) and a sixth transmission line (12), the other end of the sixth transmission line (12) is connected with a resistor (13), the other end of the resistor (13) is connected with a seventh transmission line (12 '), the other end of the seventh transmission line (12 ') is respectively connected with a fifth transmission line (11 ') and a third transmission line (10 '), and the other end of the third transmission line (10 ') is connected with the other first transmission line (8).

5. A wideband equal power splitting/combining circuit topology with wideband depth isolation according to claim 4, wherein: the impedance and the electrical length of the second transmission line (10) and the third transmission line (10') are respectively Z_i1＝48Ω，θ_i1146 °; the impedance and the electrical length of the fourth transmission line (11) and the fifth transmission line (11') are respectively Z_i2＝48Ω，θ_i25 DEG, the characteristic impedance and the electrical length of the sixth transmission line (12) and the seventh transmission line (12') are Z_i3＝48Ω，θ_i332 °; the resistance value of the resistor (13) is R_i＝68Ω。

6. A wideband equal power splitting/combining circuit topology with wideband depth isolation as claimed in claim 1, characterized by: the circuit topology is realized by combining a transmission line supporting TEM waves/quasi-TEM waves with surface-mounted resistors, and the transmission line supporting the TEM waves/quasi-TEM waves comprises a common microstrip transmission line, a suspended microstrip transmission line, a strip line transmission line and a ridge gap waveguide transmission line.

7. A wideband equal power splitting/combining circuit topology with wideband depth isolation as claimed in claim 1, characterized by: the circuit topology is realized by a single-layer circuit or a multi-layer circuit.

8. A wideband equal power splitting/combining circuit topology with wideband depth isolation as claimed in claim 1, characterized by: the multimode resonator (3) is realized by a transmission line multimode resonator, a substrate integrated waveguide multimode resonator, a gap waveguide multimode resonator or a concentrated LC multimode resonator.

Technical Field

The invention belongs to the technical field of electromagnetic fields and microwaves, and particularly relates to a broadband equipower distribution/synthesis circuit topology with broadband deep isolation, which is particularly suitable for a network requiring broadband deep isolation for broadband power distribution/synthesis.

Background

In the design of communication and radar front-end systems, a power distribution/synthesis circuit is an important key passive device, and can be used for the design of a power synthesis network of a power amplifier chip, a synthesis network of a phased array system, the design of an image rejection mixer and the like. Classical power splitting/combining circuits have wilkinson circuit topology and Gysel circuit topology, however their splitting/combining bandwidth and output isolation bandwidth are usually small, typically around 20%. For broadband large-scale array applications, such a bandwidth is often not enough, and the isolation requirement between channel units in such array applications is also high, so that a broadband equipower distribution/synthesis circuit with a broadband deep isolation needs to be researched.

In recent years, research on a broadband power distribution/synthesis circuit based on a classical wilkinson circuit topology is more, wherein the research is represented by a multi-stage transmission line matching technology, a multi-mode resonant cavity loading technology, a quasi-coupled line loading technology, a capacitance loading multi-stage transmission line matching technology and the like, the application of the technologies effectively increases the distribution/synthesis bandwidth and the isolation bandwidth of the power distribution/synthesis circuit, but the isolation degree is limited, and is generally about 20 dB. Therefore, researchers have proposed a technique based on complex isolation impedance and surface wave suppression to improve isolation, but such a narrow-band complex isolation impedance technique is suitable for a power division filter circuit with a relatively narrow bandwidth. For the broadband power distribution/synthesis circuit, it is also necessary to combine the broadband complex isolation impedance technology to realize the bandwidth expansion and isolation improvement simultaneously on the basis of the above broadband technology.

Disclosure of Invention

Aiming at the defects in the prior art, the invention provides a broadband equipower distribution/synthesis circuit topology with broadband deep isolation, realizes the functions of broadband power distribution/synthesis, low input-output standing waves and broadband deep output isolation, and is beneficial to large-scale array application with broadband and higher isolation requirement.

In order to achieve the purpose, the invention adopts the following technical scheme:

a broadband equal power splitting/combining circuit topology having broadband deep isolation, the circuit topology having axial symmetry, comprising: the broadband composite coupler comprises a common port, two first strong coupling feeder lines, two multimode resonators, two second strong coupling feeder lines, broadband complex isolation impedance and two distribution/synthesis ports; the public port is respectively connected to the two distribution/synthesis ports through two paths with the same structure, in each path, the public port, the first strong coupling feeder line, the multimode resonator, the second strong coupling feeder line and the distribution/synthesis ports are sequentially connected, and the broadband complex isolation impedance is connected between the two multimode resonators.

In order to optimize the technical scheme, the specific measures adopted further comprise:

furthermore, in each path, the first strong coupling feeder line adopts a first coupling transmission line, the second strong coupling feeder line adopts a second coupling transmission line, and half of the first coupling transmission line and half of the second coupling transmission line are both connected with the first transmission line, so that the multi-mode resonator is realized through a branch line technology.

Further, the even-mode characteristic impedance, the odd-mode characteristic impedance and the electrical length of the first coupled transmission line are respectively Z_e1＝150Ω，Z_o1＝30Ω，θ_c190 °; the even-mode characteristic impedance, the odd-mode characteristic impedance and the electrical length of the second coupling transmission line are respectively Z_e2＝100Ω，Z_o2＝9Ω，θ_c290 °; the characteristic impedance and the electrical length of the first transmission line are respectively Z_b＝200Ω，θ_b＝5°。

Furthermore, the broadband complex isolation impedance is composed of a second transmission line, a third transmission line, a fourth transmission line, a fifth transmission line, a sixth transmission line, a seventh transmission line and a resistor; one end of the second transmission line is connected with one of the first transmission lines, the other end of the second transmission line is respectively connected with the fourth transmission line and the sixth transmission line, the other end of the sixth transmission line is connected with the resistor, the other end of the resistor is connected with the seventh transmission line, the other end of the seventh transmission line is respectively connected with the fifth transmission line and the third transmission line, and the other end of the third transmission line is connected with the other first transmission line.

Further, the impedance and the electrical length of the second transmission line and the third transmission line are respectively Z_i1＝48Ω，θ_il146 °; impedance and electrical length of the fourth transmission line and the fifth transmission lineAre each Z_i2＝48Ω，θ_i25 DEG, the characteristic impedance and the electrical length of the sixth transmission line and the seventh transmission line are Z_i3＝48Ω，θ_i332 °; the resistance value of the resistor is R_i＝68Ω。

Furthermore, the circuit topology is realized by combining a transmission line supporting the TEM wave/the quasi-TEM wave with a surface-mounted resistor, and the transmission line supporting the TEM wave/the quasi-TEM wave comprises a common microstrip transmission line, a suspended microstrip transmission line, a strip line transmission line and a ridge gap waveguide transmission line.

Further, the circuit topology is realized by a single-layer circuit or a multi-layer circuit.

Further, the multimode resonator is implemented by a transmission line multimode resonator, a substrate integrated waveguide multimode resonator, a gap waveguide multimode resonator, or a lumped LC multimode resonator.

The invention has the beneficial effects that: the invention can simultaneously realize the functions of broadband power division/synthesis, low input and output standing waves and broadband deep output isolation, and is beneficial to the application of broadband large-scale arrays with higher isolation requirement.

Drawings

Fig. 1 is a schematic diagram of a wideband equipower distribution/synthesis circuit topology with wideband deep isolation according to the present invention.

Fig. 2 is a diagram of an embodiment of a transmission line with a wide-band equal power distribution/synthesis circuit topology with wide-band deep isolation according to the present invention.

Fig. 3a-3d are performance simulation results of transmission line embodiments of a wide-band equal power splitting/combining circuit topology with wide-band deep isolation according to the present invention, where fig. 3a shows the return loss of port 1, fig. 3b shows the power splitting transmission performance, fig. 3c shows the return loss of port 2/3, and fig. 3d shows the isolation of output port 2/3.

The reference numbers are as follows: 1. a common port; 2. a first strongly coupled feeder; 3. a multimode resonator; 4. a second strongly coupled feeder; 5. a broadband complex isolation impedance; 6. a distribution/synthesis port; 7. a first coupled transmission line; 8. a first transmission line; 9. a second coupled transmission line; 10. a second transmission line; 10', a third transmission line; 11. a fourth transmission line; 11', a fifth transmission line; 12. a sixth transmission line; 12', a seventh transmission line; 13. and (4) resistance.

Detailed Description

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

Fig. 1 is a schematic diagram of a wideband equipower distribution/synthesis circuit topology with wideband deep isolation. The power distribution/synthesis circuit topology is based on the classical Wilkinson equal power distribution/synthesis circuit topology, one fourth of the impedance transformation line is replaced by a multimode resonator, and the input and output and the multimode resonator are realized by a strong coupling feeder line technology; meanwhile, the isolation pure resistor is replaced by a broadband complex isolation impedance, and the complex isolation impedance is realized through a specific transmission line network and the pure resistor. The power splitting/combining circuit topologies are symmetric about the axis SS'.

Fig. 2 is a schematic diagram of the circuit topology of fig. 1 implemented based on transmission lines. Wherein the first coupling transmission line 7 and the second coupling transmission line 9 implement the first strong coupling feeder 2 and the second strong coupling feeder 4, respectively, in fig. 1, and half of the first coupling transmission line 7 and the second coupling transmission line 9 are connected to the first transmission line 8, implementing the multi-mode resonator 3 in fig. 1 by a branch line technique. The second transmission line 10, the third transmission line 10 ', the fourth transmission line 11, the fifth transmission line 11 ', the sixth transmission line 12, and the seventh transmission line 12 ' constitute branch line transmission lines on the isolation branch and together with the resistor 13 constitute the broadband complex isolation impedance 5 in fig. 1.

As shown in fig. 2, the specific circuit parameters are: z_e1＝150Ω，Z_o1＝30Ω，θ_c1＝90°，Z_e2＝100Ω，Z_o2＝9Ω，θ_c2＝90°，Z_b＝200Ω，θ＝5°，Z_i1＝48Ω，θ_i1＝146°，Z_i2＝48Ω，θ_i2＝5°，Z_i3＝48Ω，θ_i3＝32°，R_i＝68Ω。

The equipower distribution/synthesis circuit topology provided by the invention can be realized by combining transmission lines supporting TEM waves/quasi-TEM waves such as a common microstrip transmission line, a suspended microstrip transmission line, a strip line transmission line, a ridge gap waveguide transmission line and the like with surface-mounted resistors, can be realized by a single-layer circuit or a multi-layer circuit, and can be realized by a transmission line multimode resonator, a substrate integrated waveguide multimode resonator, a gap waveguide multimode resonator, a centralized LC multimode resonator and the like.

Fig. 3 is a graph of simulation results of an ideal transmission line embodiment of a broadband equal power distribution/synthesis circuit topology with broadband deep isolation proposed in the present invention, where fig. 3a shows the return loss of port 1, fig. 3b shows the power distribution transmission performance (equal power distribution 3dB bandwidth is about 76.8%), fig. 3c shows the return loss of port 2/3, and fig. 3d shows the isolation of output port 2/3 (port isolation better than 40dB is achieved in the frequency range of 7.2GHz to 12.0 GHz). As can be seen from the drawings, the broadband power splitting/synthesizing device can simultaneously realize broadband power splitting/synthesizing, low input-output standing waves and broadband deep output isolation functions, and is beneficial to large-scale array application with broadband and higher isolation requirement.

The above is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above-mentioned embodiments, and all technical solutions belonging to the idea of the present invention belong to the protection scope of the present invention. It should be noted that modifications and embellishments within the scope of the invention may be made by those skilled in the art without departing from the principle of the invention.