Broadband digital phase shifter based on artificial surface plasmons

Abstract

The application discloses a kind of wideband digital phase shifters based on artificial surface plasmon, including dielectric substrate (1), 50Ω microstrip line (2), impedance and wave vector matching section (3), interdigital capacitive structure (4), phase shifter branch (5), PIN diode channel (6) and feed network (7);50Ω microstrip line (2) is connected with external device SMA joint;Impedance and wave vector matching section (3) converts electromagnetic wave transmission mode from quasi-TEM mode into TM mode, forms the transmission mode of artificial surface plasmon;Interdigital capacitive structure (4) can realize independent control to artificial surface plasmon branch;Phase shifter branch (5) can realize digital phase shift;PIN diode channel (6) and feed network (7) jointly constitute control system.It can realize independent control to artificial surface plasmon branch, and can realize wideband phase shift.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of electromagnetic regulation, and particularly relates to a wideband digital phase shifter based on artificial surface plasmon polaritons. BACKGROUND

[0002] Spoof Surface Plasmon Polaritons (SSPP) is a new type of plasmon wave induced in artificial micro-nano structures, and the SSPP originates from Surface Plasmon Polaritons (SPP). The SSPP combines the advantages of micro-nano system technology and surface plasmon technology, can enhance and control electromagnetic field, and has a unique advantage in device design.

[0003] The phase shifter is one of the key components of microwave and millimeter wave systems, and is widely used in radars, phased array antennas, modulators, measurement and instrument systems, and beam forming networks. Low loss, wide bandwidth, compact size, simple structure, and equal length of reference line and main line are the main challenges in designing the phase shifter. However, the current research on the phase shifter based on artificial surface plasmon polaritons cannot realize digital control, and stable phase control in a wide frequency band. SUMMARY

[0004] The application aims to provide a wideband digital phase shifter based on artificial surface plasmon polaritons, so as to solve the technical problem that the current research on the phase shifter based on artificial surface plasmon polaritons cannot realize digital step control, and stable phase control in a wide frequency band.

[0005] To solve the above technical problems, the specific technical scheme of the application is as follows:

[0006] A wideband digital phase shifter based on artificial surface plasmon polaritons, comprising a dielectric substrate, a 50Ω microstrip line, an impedance and wave vector matching section, an interdigital capacitance structure, a phase shifter branch, and a PIN diode channel.

[0007] The 50Ω microstrip line, the impedance and wave vector matching section, the interdigital capacitance structure, and the phase shifter branch of the digital phase shifter are all made on the dielectric substrate based on the PCB process.

[0008] The 50Ω microstrip line is connected with an SMA joint and is arranged as an input end; the 50Ω microstrip line is connected with an impedance and wave vector matching section, which converts quasi-TEM mode electromagnetic waves into TM mode artificial surface plasmon transmission; the impedance and wave vector matching section is connected with a phase shifter branch in sequence through an interdigital capacitance structure; the phase shifter branch is composed of two upper and lower metal sheets, the upper metal sheet is connected with the metal ground on the back surface through a metal via hole penetrating the dielectric substrate and the metal ground; the two metal sheets are connected through a PIN diode channel welded between the upper and lower metal sheets; the interdigital capacitance structure is connected between the wave vector matching section (3) and the phase shifter branch, and between every two phase shifter branches, so as to realize the separation of the phase shifter branch.

[0009] Further, the broadband digital phase shifter based on artificial surface plasmon further comprises a feed network connected with the phase shifter branch to provide a direct current voltage required for the on-off of the PIN diode channel.

[0010] Further, the phase shifter branch comprises a lower branch, an upper branch and a metal via hole;

[0011] The upper branch and the metal ground are connected through a metal via hole penetrating the dielectric substrate and the metal ground, and the upper branch and the lower branch are connected through a PIN diode channel welded between the upper and lower metal sheets.

[0012] Further, the feed network comprises an inductive element loaded thereon.

[0013] The broadband digital phase shifter based on artificial surface plasmon has the following advantages:

[0014] The digital phase shifter adopts the interdigital capacitance structure to isolate the direct current DC signal and separate the phase shifter branch, so that different direct current bias voltages can be provided for different phase shifter branches, the switch state of the PIN diode channel is individually controlled, and digital phase shifting is realized.

[0015] The digital phase shifter is based on the PCB process, simple to manufacture, and has the characteristics of simple structure and easy installation after being manufactured; when the digital phase shifter is designed, the cooperative design with other circuit structures is comprehensively considered, and the bandwidth performance of the digital phase shifter is obviously improved. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 is a three-dimensional schematic view of the broadband digital phase shifter in the embodiment of the application;

[0017] Figure 2 is a three-dimensional schematic view of the unit structure of the broadband digital phase shifter in the embodiment of the application;

[0018] Figure 3is a top view of a unit structure of a wideband digital phase shifter in an embodiment of the present application;

[0019] Figure 4 is a top view of an interdigital capacitance structure of a wideband digital phase shifter in an embodiment of the present application;

[0020] Figure 5(a) is a schematic diagram of S parameter transmission coefficient results of a wideband digital phase shifter in an embodiment of the present application;

[0021] Figure 5(b) is a schematic diagram of S parameter phase results of a wideband digital phase shifter in an embodiment of the present application;

[0022] Figure 6 is a schematic diagram of a planar view of a wideband digital phase shifter of the present application;

[0023] The figure is marked as follows: 1, dielectric substrate; 2, microstrip line; 3, impedance and wave vector matching section; 4, interdigital capacitance structure; 5, phase shifter branch; 6, PIN diode channel; 7, feed network; 8, metal ground; 51, lower branch; 52, upper branch; 53, metal via. DETAILED DESCRIPTION

[0024] In order to better understand the purpose, structure and function of the present application, a wideband digital phase shifter based on artificial surface plasmons is described in further detail below in combination with the drawings.

[0025] Reference Figure 1 , Figure 2 , Figure 3 as shown, Figure 1 is a schematic diagram of a wideband digital phase shifter structure of an embodiment, including a 50Ω microstrip line 2, an impedance and wave vector matching section 3, an interdigital capacitance structure 4, a phase shifter branch 5, and a PIN diode channel 6.

[0026] The 50Ω microstrip line is connected to an SMA connector and is set as an input end; the 50Ω microstrip line 2 is connected to the impedance and wave vector matching section 3 to convert quasi-TEM mode electromagnetic waves into TM mode artificial surface plasmon transmission; the phase shifter branch 5 is composed of an upper metal sheet and a lower metal sheet, the upper metal sheet is connected to the metal ground 8 by a through hole; the two metal sheets are connected by the PIN diode channel 6; the interdigital capacitance structure 4 separates the phase shifter branch.

[0027] The PIN diode channel 6 loads a PIN diode, which is soldered between the upper and lower metal sheets of the phase shifter branch 5 to connect the upper and lower metal sheets of the phase shifter branch 5, and the two states of the PIN diode determine two different dispersions of the phase shifter branch 5, and there will be a fixed wave vector difference between the two states. The height of the lower metal sheet of the phase shifter branch 5 determines the cutoff frequency of the PIN diode in the off state; the upper metal sheet determines the upper and lower cutoff frequencies of the PIN diode in the on state.

[0028] The 50Ω microstrip line 2, the impedance and wave vector matching section 3, the interdigital capacitive structure 4 and the phase shifter branch 5 are all made of copper and plated with gold on the dielectric substrate 1 by the PCB process.

[0029] In the above broadband digital phase shifter, the 50Ω microstrip line 2, the impedance and wave vector matching section 3, the interdigital capacitive structure 4 and the phase shifter branch 5 are all made of copper and plated with gold on the dielectric substrate 1 by the PCB process, wherein the electromagnetic wave is input from the 50Ω microstrip line 2, and is successfully converted from the quasi-TEM mode electromagnetic wave to the TM mode artificial surface plasmon transmission mode wave through the impedance and wave vector matching section 3, and then the electromagnetic wave passes through the phase shifter branch 5 with different states, and accumulates different phase differences to realize digital phase shift transmission.

[0030] Reference Figure 4 As shown, the interdigital capacitive structure 4 can isolate the DC signal of the digital phase shifter, independently control the branch of the artificial surface plasmon, and control the phase step of the digital phase shifter.

[0031] The digital phase shifter further comprises a feed network 7 connected to the phase shifter branch 5.

[0032] The phase shifter branch 5 comprises a lower branch 51, an upper branch 52 and a metal via hole 53;

[0033] The upper branch 52 and the metal ground 8 are connected through the metal via hole 53, and the upper branch 52 and the lower branch 51 are connected through the PIN diode channel 6. The electromagnetic wave is transmitted in the artificial surface plasmon waveguide, and the dispersion is controlled according to the two different states of the PIN diode, so as to obtain the phase difference of the two different states and realize the digital phase shift function.

[0034] The feed network 7 comprises an inductive element loaded on an open circuit.

[0035] As shown in FIG. 5, it can be seen from the curve that the performance of the digital phase shifter is good in the wide frequency band range of 4.5GHz-5.5GHz, the phase step is stable, the transmission efficiency is high, and the insertion loss is low. The test results show that the above broadband digital phase shifter has good broadband performance, stable phase shift effect, and can be used in a digital modulation system.

[0036] Compared with the prior art, the above digital phase shifter is based on the PCB process, is simple to manufacture, has the characteristics of simple structure and easy installation after being manufactured, and obviously improves the bandwidth performance of the digital phase shifter by comprehensively considering the collaborative design with other circuit structures in the design of the digital phase shifter. The process adopted by the present application is the PCB process, which is simple to process and convenient for system integration.

[0037] Any combination of the technical features of the above embodiments can be made, and for the sake of brevity, not all possible combinations are described, however, it is to be understood that the scope of protection includes all possible combinations of the technical features.

[0038] It is to be understood that the present application is described by way of example only, and that modifications and variations of the features and embodiments described can be made by those skilled in the art without departing from the spirit or scope of the application. Further, it is to be understood that the features and embodiments described can be modified to suit particular situations and materials without departing from the spirit or scope of the application. Accordingly, the application is not to be limited by the specific embodiments described herein, but only by the scope of the appended claims.

Claims

1. A plasmonic artificial surface based wideband digital phase shifter, characterized in that, The device comprises a dielectric substrate (1), a 50Ω microstrip line (2), an impedance and wave vector matching section (3), an interdigital capacitance structure (4), a phase shifter branch (5), and a PIN diode channel (6); The 50Ω microstrip line (2), the impedance and wave vector matching section (3), the interdigital capacitance structure (4), and the phase shifter branch (5) of the digital phase shifter are all made on the dielectric substrate (1) based on the PCB process; The 50Ω microstrip line (2) is connected with an SMA connector and is set as an input end; the 50Ω microstrip line (2) is connected with the impedance and wave vector matching section (3) to convert a quasi-TEM mode electromagnetic wave into a TM mode artificial surface plasmon transmission; the impedance and wave vector matching section (3) is connected with the phase shifter branch (5) in sequence through the interdigital capacitance structure (4); the phase shifter branch (5) is composed of an upper metal sheet and a lower metal sheet, the upper metal sheet is connected with the metal ground (8) on the back surface through a metal via hole penetrating through the dielectric substrate (1) and the metal ground (8); the two metal sheets are connected through the PIN diode channel (6) welded between the upper and lower metal sheets; the interdigital capacitance structure (4) is connected between the wave vector matching section (3) and the phase shifter branch (5) and between every two phase shifter branches (5) to realize the separation of the phase shifter branch (5).

2. The artificial surface plasmon based wideband digital phase shifter of claim 1, wherein, The device further comprises a feeding network (7) connected with the phase shifter branch (5) to provide a direct current voltage required for the on-off of the PIN diode channel (6).

3. The artificial surface plasmon based wideband digital phase shifter of claim 1, wherein, The phase shifter branch (5) comprises a lower branch (51), an upper branch (52), and a metal via hole (53); The upper branch (52) and the metal ground (8) are connected through the metal via hole (53) penetrating through the dielectric substrate (1) and the metal ground (8), and the upper branch (52) and the lower branch (51) are connected through the PIN diode channel (6) welded between the upper and lower metal sheets.

4. The artificial surface plasmon based wideband digital phase shifter of claim 2, wherein, The feeding network (7) comprises an inductive element loaded thereon.

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