A broadband quadrature phase shift topology and applications thereof

Abstract

The application discloses a novel broadband quadrature phase shift topology and specific application thereof, comprising a signal source, a matching structure, an open circuit coupling output and a short circuit coupling output; energy output by the signal source is transmitted to the open circuit coupling output and the short circuit coupling output in two paths respectively after the matching structure, and the open circuit coupling output and the short circuit coupling output are coupled with the matching structure respectively, and the matching structure is used for realizing impedance matching; the realization mode of the topology comprises but is not limited to microstrip line, slot line, coplanar strip line and other transmission line forms, the realization mode of the matching structure comprises but is not limited to quarter wavelength impedance conversion line, multi-section matching structure and other matching structures, and the coupling form comprises but is not limited to side edge coupling, multi-layer coupling and other coupling structures.The 90-degree phase shifter provided by the application has the advantages of compact structure, stable 90-degree phase difference and wide phase bandwidth, and is very suitable for modern wireless communication systems.

Description

Technical Field

[0001] This invention belongs to the field of microwave passive device technology, specifically a broadband orthogonal phase-shift topology and its specific applications. Background Technology

[0002] A 90-degree phase shifter is an important passive device in microwave and millimeter-wave systems that delays the phase, and it is widely used, especially in antenna feed networks, balanced amplifiers, and balanced mixers. Therefore, it is essential to design a compact 90-degree phase shifter with stable phase shift.

[0003] Currently, traditional phase shifter implementation methods can be divided into two types. The first method often constructs a wide-bandgap phase difference by designing a reference path and a phase shift path separately. For example, in reference 1 (Liu, Y. Liu, J. Shen, S. Li, C. Yuan and Y. Lu, "Wideband Single-Layer 90° Phase Shifter Using Stepped Impedance OpenStub and Coupled-Line With Weak Coupling," in IEEE Microwave and Wireless Components Letters, vol. 24, no. 3, pp. 176-178, March 2014, doi:10.1109 / LMWC.2013.2295212.), a stepped impedance line is used to design the phase shift path, thus forming a 90-degree phase difference with the reference path. However, this design method requires complex circuit model analysis during design, and the resulting phase shift structure is not compact enough. The second design method summarizes the field characteristics under different phases to design corresponding phase-shifting structures. For example, in reference 2 (Y. Kim, S. Song and KW Kim, "A Pair of Ultra-Wideband Planar Transitions for Phase Inversion Applications," in IEEE Microwave and Wireless Components Letters, vol. 20, no. 9, pp. 492-494, Sept. 2010, doi:10.1109 / LMWC.2010.2051800.), field reversal is achieved by controlling the field, ultimately realizing a 180-degree phase shift. This design method produces a relatively compact phase-shifting structure and makes it easier to achieve broadband phase shifts. However, the difficulty lies in summarizing the relationship between different phase shifts and field distributions, and currently it is only widely used in 180-degree phase-shifting structures. Therefore, summarizing the correspondence between a 90-degree phase shift and field distribution, and realizing the design of a highly compact 90-degree phase shifter with a wide phase shift bandwidth, is of great significance. Summary of the Invention

[0004] The purpose of this invention is to provide a broadband 90-degree phase-shift topology with a simple structure and stable phase difference.

[0005] The technical solution to achieve the purpose of this invention is as follows: a broadband orthogonal phase-shift topology, which includes a signal source, a matching structure, an open-circuit coupled output, and a short-circuit coupled output; the energy output from the signal source is transmitted to the open-circuit coupled output and the short-circuit coupled output respectively after passing through the matching structure, and the open-circuit coupled output and the short-circuit coupled output are coupled to the matching structure respectively, and the matching structure is used to achieve impedance matching; the implementation of this topology includes, but is not limited to, transmission line forms such as microstrip lines, slot lines, and coplanar striplines, and the implementation of the matching structure includes, but is not limited to, matching structures such as quarter-wavelength impedance conversion lines and multi-section matching structures, and the coupling forms include, but are not limited to, side coupling and multi-layer coupling.

[0006] An application of a broadband orthogonal phase-shift topology includes a dielectric substrate and a metal ground arranged sequentially from top to bottom, and an input port, a first quarter-wavelength transmission line, a second quarter-wavelength transmission line, a first metal via, a third quarter-wavelength transmission line, a fourth quarter-wavelength transmission line, a second metal via, a first output port, and a second output port located on the upper surface of the dielectric substrate.

[0007] The input port is connected to the second quarter-wavelength transmission line via a first quarter-wavelength transmission line, and the end of the second quarter-wavelength transmission line is short-circuited to the metal ground via a first metal via. The third quarter-wavelength transmission line and the fourth quarter-wavelength transmission line are located on both sides of the second quarter-wavelength transmission line and are connected to the first output port and the second output port respectively. The end of the fourth quarter-wavelength transmission line is short-circuited to the metal ground via a second metal via, serving as a short-circuit coupled output of the broadband orthogonal phase-shift topology. The end of the third quarter-wavelength transmission line is open-circuited, serving as an open-circuit coupled output of the broadband orthogonal phase-shift topology. The input port serves as a signal source, and the second quarter-wavelength transmission line serves as a matching structure.

[0008] Furthermore, the first output port and the second output port have the same amplitude and a phase difference of 90 degrees.

[0009] Furthermore, the characteristic impedance of the input port, the first output port, and the second output port is all 50Ω.

[0010] Furthermore, the third quarter-wavelength transmission line and the fourth quarter-wavelength transmission line are placed parallel to each other on both sides of the second quarter-wavelength transmission line and coupled by side coupling. The coupling method includes, but is not limited to, side coupling and upper and lower layer coupling.

[0011] Furthermore, the spacing between the second quarter-wavelength transmission line and the third and fourth quarter-wavelength transmission lines is adjustable to regulate the coupling strength; the smaller the spacing, the stronger the coupling strength.

[0012] Compared with the prior art, the significant advantages of this invention are:

[0013] (1) The structure is simple and easy to process.

[0014] (2) A wideband 90-degree phase difference was achieved by controlling the open-circuit and short-circuit boundary conditions of the coupling line.

[0015] The present invention will now be described in further detail with reference to the accompanying drawings. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the broadband orthogonal phase-shift topology of the present invention.

[0017] Figure 2 This is a schematic diagram of the broadband orthogonal phase shift topology for realizing a broadband 90-degree phase difference in an embodiment of the present invention. Figure (a) shows the transmission line with the terminal open and Figure (b) shows the transmission line with the terminal short.

[0018] Figure 3 This is a specific structural diagram and physical parameter schematic diagram of an embodiment of the present invention.

[0019] Figure 4 This is a graph showing the phase difference of the output port as a function of frequency in an embodiment of the present invention.

[0020] Figure 5 The figure shows the simulation results of the S-parameters in an embodiment of the present invention.

[0021] Figure 6 The diagram shows the phase difference and amplitude imbalance results of the novel broadband phase shifter with a 90-degree phase shift according to an embodiment of the present invention. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0023] It should be noted that if the embodiments of the present invention involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicators will also change accordingly.

[0024] Furthermore, if the embodiments of this invention involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. If the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0025] In one embodiment, combined Figure 1 A broadband orthogonal phase-shift topology is provided, including a signal source, a matching structure, an open-circuit coupled output, and a short-circuit coupled output. The energy output from the signal source is split into two paths after passing through the matching structure and transmitted to the open-circuit coupled output and the short-circuit coupled output, respectively. The open-circuit coupled output and the short-circuit coupled output are coupled to the matching structure, which is used to achieve impedance matching. The implementation of this topology includes, but is not limited to, transmission line forms such as microstrip lines, slot lines, and coplanar striplines. The implementation of the matching structure includes, but is not limited to, matching structures such as quarter-wavelength impedance conversion lines and multi-section matching structures. The coupling forms include, but are not limited to, side coupling and multi-layer coupling.

[0026] Application of the above-mentioned broadband orthogonal phase shift topology: A novel broadband phase shifter with a 90-degree phase shifter includes a dielectric substrate 1 and a metal ground 2 arranged sequentially from top to bottom, wherein the dielectric substrate has a thickness of 1.5 mm and a dielectric constant of 2.2, and an input port 3, a first quarter-wavelength transmission line 4, a second quarter-wavelength transmission line 5, a first metal via 6, a third quarter-wavelength transmission line 7, a fourth quarter-wavelength transmission line 8, a second metal via 9, a first output port 10, and a second output port 11 located on the upper surface of the dielectric substrate 1;

[0027] The input port 3 is connected to the second quarter-wavelength transmission line 5 via the first quarter-wavelength transmission line 4, and the end of the second quarter-wavelength transmission line 5 is short-circuited to the metal ground 2 via the first metal via 6. The third quarter-wavelength transmission line 7 and the fourth quarter-wavelength transmission line 8 are located on both sides of the second quarter-wavelength transmission line 5 and are connected to the first output port 10 and the second output port 11 respectively. The end of the fourth quarter-wavelength transmission line 8 is short-circuited to the metal ground 2 via the second metal via 9, serving as a short-circuit coupled output of the broadband orthogonal phase-shift topology. The end of the third quarter-wavelength transmission line 7 is open-circuited, serving as an open-circuit coupled output of the broadband orthogonal phase-shift topology, thereby forming a stable 90-degree phase difference between the first output port 10 and the second output port 11. The input port 3 serves as the signal source, and the second quarter-wavelength transmission line 5 serves as the matching structure; its width affects the matching effect of the input port.

[0028] The working principle of this novel broadband 90-degree phase shifter is as follows: the signal passes through input port 1, undergoes impedance conversion via the first quarter-wavelength transmission line 4, and then enters the second quarter-wavelength transmission line 5. The second quarter-wavelength transmission line 5, through side coupling, couples the energy to the third quarter-wavelength transmission line 7 and the fourth quarter-wavelength transmission line 8, respectively. Simultaneously, for example... Figure 2 As shown, for transmission lines of the same length with short-circuited and open-circuited terminals, their input voltages can be expressed as the port voltages using the following formulas:

[0029] V 开路 =V0 + [e -jβl +e jβl ] = 2V0 + cosβl

[0030] V 短路 =V0 + [e -jβl -e jβl ]=2jV0 + sinβl

[0031] The phase difference is as follows:

[0032]

[0033] Therefore, there is a 90-degree phase difference between the fourth quarter-wavelength transmission line, which is short-circuited through the second metal via 9, and the third quarter-wavelength transmission line 7, which is open-circuited.

[0034] As a specific example, the invention is further illustrated in one embodiment.

[0035] The structure of a specific application example of the novel broadband 90-degree phase-shift topology in this embodiment is as follows: Figure 3 As shown, the specific dimensions and specifications are as follows. Figure 4 As shown. The dielectric substrate 1 used has a relative permittivity of 2.2 and a thickness of 1.5 mm. The dimensional parameters of the new broadband phase shifter with a 90-degree phase shift are as follows: W1 = 3.5 mm, W2 = 3.5 mm, W3 = 0.4 mm, W4 = 4.6 mm, l1 = 30 mm, l2 = 30.6 mm, l3 = 30.6 mm, r1 = 0.8 mm, g1 = 0.5 mm.

[0036] This embodiment was modeled and simulated using the electromagnetic simulation software HFSS.20, and tested simultaneously on an Agilent N5244A four-port vector network analyzer. The S-parameters of the proposed novel broadband phase-shifting 90-degree phase shifter are as follows: Figure 5 As shown, by Figure 5 It can be seen that the center frequency of the phase-shifting power divider is 1.66 GHz, the 15 dB impedance bandwidth is 4.8%, and the minimum insertion loss in the passband is 0.46 dB. Figure 6 The phase difference and amplitude imbalance of the proposed novel broadband phase-shifting 90-degree phase shifter are addressed by... Figure 5 It can be seen that the two output ports can maintain a 90-degree phase difference (with a tolerance of ±5 degrees) in the range of 0.5GHz to 2.4GHz, with a relative bandwidth of 131%, and an amplitude imbalance of less than 0.43dB in the passband.

[0037] In summary, the novel broadband phase shifter with a 90-degree phase shift proposed in this invention achieves a stable 90-degree phase difference while ensuring high performance and miniaturization, making it highly suitable for modern wireless communication systems.

[0038] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed invention.

Claims

1. A broadband orthogonal phase-shift topology, characterized in that, It includes a dielectric substrate (1) and a metal ground (2) arranged sequentially from top to bottom, and an input port (3), a first quarter-wavelength transmission line (4), a second quarter-wavelength transmission line (5), a first metal via (6), a third quarter-wavelength transmission line (7), a fourth quarter-wavelength transmission line (8), a second metal via (9), a first output port (10), and a second output port (11) located on the upper surface of the dielectric substrate (1). The input port (3) is connected to the second quarter-wavelength transmission line (5) through the first quarter-wavelength transmission line (4), and the end of the second quarter-wavelength transmission line (5) is short-circuited to the metal ground (2) through the first metal via (6); the third quarter-wavelength transmission line (7) and the fourth quarter-wavelength transmission line (8) are located on both sides of the second quarter-wavelength transmission line (5), and are connected to the first output port (10) and the second output port (11) respectively, and the end of the fourth quarter-wavelength transmission line (8) is short-circuited to the metal ground (2) through the second metal via (9), serving as the short-circuit coupling output of the broadband orthogonal phase shift topology, and the end of the third quarter-wavelength transmission line (7) is open-circuited as the open-circuit coupling output of the broadband orthogonal phase shift topology, the input port (3) serves as the signal source, and the second quarter-wavelength transmission line (5) serves as the matching structure.

2. The broadband orthogonal phase-shift topology according to claim 1, characterized in that, The first output port (10) and the second output port (11) have the same amplitude and a phase difference of 90 degrees.

3. The broadband orthogonal phase-shift topology according to claim 1, characterized in that, The characteristic impedance of the input port (3), the first output port (10), and the second output port (11) is 50Ω.

4. The broadband orthogonal phase-shift topology according to claim 1, characterized in that, The third quarter-wavelength transmission line (7) and the fourth quarter-wavelength transmission line (8) are placed parallel to each other on both sides of the second quarter-wavelength transmission line (5) and are coupled by side coupling. The coupling methods include side coupling and upper and lower layer coupling.

5. The broadband orthogonal phase-shift topology according to claim 1, characterized in that, The spacing between the second quarter-wavelength transmission line (5) and the third quarter-wavelength transmission line (7) and the fourth quarter-wavelength transmission line (8) is adjustable to adjust the coupling strength. The smaller the spacing, the stronger the coupling strength.

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