Dual-mode phase shifter based on artificial surface plasmon

Abstract

The invention discloses a dual-mode phase shifter based on artificial surface plasmon. The dual-mode phase shifter comprises a dual-mode transmission structure, a dual-mode excitation structure and a direct current control structure, the dual-mode transmission structure realizes simultaneous transmission of an even mode and an odd mode in a single physical channel; the dual-mode excitation structure ensures efficient excitation of an even mode and an odd mode, the even mode is directly excited by a microstrip port, and the odd mode is indirectly excited by a microstrip-slot line coupling mode; the DC control structure realizes real-time control of two modes of the dual-mode transmission structure. According to the invention, simultaneous transmission of an even mode and an odd mode under the same frequency and a single physical channel is realized, and independent control of phase electromagnetic characteristics of the two modes is realized according to the control method after introduction of semiconductor devices such as a variable capacitance diode, so that independent phase shift of two paths of signals under the same frequency is realized simultaneously, and the signal transmission efficiency is improved. And the phase shift ranges of the two paths of signals both cover 360 degrees.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of artificial electromagnetic materials, and particularly relates to a dual-mode phase shifter based on spoof surface plasmon polaritons. BACKGROUND

[0002] With the increasing integration of microwave circuits and systems, the electromagnetic environment of the system is becoming more and more complex, which makes the electromagnetic compatibility problem worse and the flexibility and miniaturization design more difficult. Enhancing the multiplexing capability of the transmission channel and combining multiple signals in a single physical channel for simultaneous transmission are effective means to improve the system integration and realize miniaturization. The existing technology often adopts the method of integrating two transmission lines on the same medium to form a composite structure to simultaneously transmit dual signals, but at this time the two modes have different working frequencies, and the essence is still two independent transmission lines. Spoof Surface Plasmon Polaritons (SSPPs) is a kind of electromagnetic mode that simulates the excellent characteristics of surface plasmon polaritons in the optical frequency band, such as field confinement and field enhancement, which is widely used in microwave devices and systems such as filters, couplers, amplifiers, frequency doublers and communication systems. The multi-mode characteristic of spoof surface plasmon polaritons can realize the same frequency mode division multiplexing of a single channel, but due to the lack of dynamic regulation ability and multi-mode transmission ability of spoof surface plasmon polaritons, only two signals are transmitted at the same frequency at present, and the real-time independent control of the amplitude and phase of the electromagnetic characteristics of the two signals cannot be realized, which is not suitable for multi-functional active link and system with high degree of freedom and flexibility.

[0003] In 2024, Pei Hang He and Hao Chi Zhang et al. proposed a reconfigurable dual-mode meta-waveguide based on spoof surface plasmon polaritons in their published paper "Reconfigurable dual-mode meta-waveguide", which realized the independent transmission of two modes by integrating diodes in the waveguide unit. However, this method still has the following shortcomings: no phase regulation ability.

[0004] In 2025, Gaiping Hao and Wenyao Zou et al. proposed a transmission line based on artificial surface plasmons to transmit two modes in the same frequency band in their paper "Spoof surface plasmonic circuit supporting both odd-mode and even-mode transmissions". However, this method still has shortcomings: it requires port switching to achieve the switching between the two modes, and cannot transmit both modes simultaneously. In summary, the disadvantages of the existing technology are: First, the two modes operate in different frequency bands, and the feeding structure needs to be changed to achieve the switching of transmission modes. Second, even with independent transmission of the two modes, the phase cannot be independently controlled. Third, it requires port switching to achieve the switching between the two modes, and cannot transmit both modes simultaneously. Summary of the Invention

[0005] To overcome the shortcomings of the existing technology, the present invention aims to provide a dual-mode phase shifter based on artificial surface plasmon resonances, which enables simultaneous transmission of even-mode and odd-mode signals at the same frequency and a single physical channel. Furthermore, based on the control method described after introducing semiconductor devices such as varactor diodes, the phase electromagnetic characteristics of the two modes are independently controlled, thereby achieving independent phase shifting of two signals at the same frequency, with both signals covering a phase shift range of 360°.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0007] A dual-mode phase shifter based on artificial surface plasmons includes a dual-mode transmission structure, a dual-mode excitation structure, and a DC control structure. The dual-mode transmission structure consists of n adjustable modulus division multiplexing units with period p of artificial surface plasmons, used to simultaneously transmit even-mode and odd-mode signals in a single physical channel. The dual-mode excitation structure ensures the excitation effect of both even-mode and odd-mode signals; even-mode signals are directly excited using microstrip ports, while odd-mode signals are indirectly excited using microstrip-slotline coupling. The DC control structure enables real-time control of both modes of the dual-mode transmission structure.

[0008] The artificial surface plasmon mode multiplexing adjustable unit includes three metal layers: M1, M2 and M3.

[0009] Between the metal layers are two dielectric layers, and the width of each metal layer and dielectric layer is p.

[0010] In the three metal layers:

[0011] On the M1 layer, a center strip is provided through along the width direction thereof, two open-circuit branches are symmetrically provided on both sides of the center strip along the length direction thereof, a gap is left between the center strip and the open-circuit branches, two varactor diodes are symmetrically introduced at the gap for connection, control of the even mode is realized, and the capacitances of the two varactor diodes are equal;

[0012] On the M2 layer, a gap is provided through along the width direction of the layer, excitation of the odd mode is realized, two metal vias are respectively designed on both sides of the gap along the length direction thereof, and the metal vias are used for connection of the M2 layer and the M3 layer.

[0013] On the M3 layer, a metal patch is respectively placed at positions corresponding to the two metal vias, and a varactor diode is connected across the two metal patches, for realizing control of the odd mode.

[0014] The even mode microstrip port is directly connected to both sides of the dual-mode transmission structure;

[0015] The odd mode is indirectly excited in a microstrip-slot line coupling manner, and the two microstrip ports are on the back of the bottom plate.

[0016] The direct current control structure is used for realizing real-time control of the two modes, and is divided into an even mode state control area and an odd mode state control area.

[0017] The even mode state control area is responsible for real-time control of electromagnetic characteristics of the even mode, including two varactor diodes of the dual-mode transmission structure placed at the gap of the M1 layer and symmetric about the center strip, and a choke structure placed on the M3 layer.

[0018] The choke structure adopts a parallel fan-shaped structure capacitor design, the working frequency band is changed by adjusting the radius of the fan-shaped capacitor and the distance to the feeding position, and the choke structure prevents crosstalk caused by the entry of radio frequency signals into the direct current path; the upper half and the lower half of the parallel branch terminals are connected to the choke structure of the M3 layer through the metal vias, pass through the defect ground of the M2 layer, and are in communication with the metal patch applying the direct current voltage V1.

[0019] By applying a direct current voltage V1 to the metal patch on the M3 layer and a direct current voltage V2 to the center strip, an even mode control voltage Ve = V1-V2 can be applied to both ends of the varactor diode of the M1 layer, and the even mode capacitance Ce is controlled.

[0020] The odd mode state control area is responsible for real-time control of electromagnetic characteristics of the odd mode, the M3 layer is connected to the varactor diodes on both sides of the metal ground of the M2 layer through the metal vias, the metal ground of the M2 layer is divided into an upper half and a lower half by a long gap, the upper half of the metal ground applies a direct current voltage V3, the lower half of the metal ground applies a direct current voltage V4, an odd mode control voltage Vo = V3-V4 is applied to both ends of the varactor diode of the M3 layer, and the odd mode capacitance Co is controlled.

[0021] The long slit of the M2 layer is provided with a radio frequency communication area, and the long slit is designed with a bending part, which reserves a welding position for the radio frequency SMA joint while adjusting the coupling excitation efficiency.

[0022] To realize independent control of the even mode and the odd mode, a compensation method for the electromagnetic characteristics of the odd mode is adopted, that is, in the regulation process, the even mode control voltage is changed first to regulate the electromagnetic characteristics of the even mode, then the odd mode control voltage is changed to restore the electromagnetic state of the odd mode, and finally the odd mode control voltage is further changed to regulate the electromagnetic characteristics of the odd mode; the whole process realizes independent regulation of the electromagnetic characteristics of the two modes by adjusting the combination (Ve, Vo) of the even mode control voltage and the odd mode control voltage.

[0023] The beneficial effects of the present application are as follows:

[0024] The dual-mode phase shifter based on the multi-mode characteristics of artificial surface plasmons can realize simultaneous transmission and independent control of the even mode and the odd mode at the same frequency, which significantly improves the flexibility, integration and miniaturization level of the system.

[0025] The dual-mode phase shifter can simultaneously realize independent phase shifting of two signals within 360° at the same frequency, and the two signals have high isolation and do not interfere with each other during transmission and regulation.

[0026] The dual-mode phase shifter is composed of an artificial surface plasmon mode division multiplexing unit, which has good field confinement characteristics and orthogonality between the two modes, and has significant advantages in realizing inter-channel coupling suppression and solving signal integrity problems.

[0027] The artificial surface plasmon mode division multiplexing unit adopted in the present application realizes control of the dispersion characteristics of artificial surface plasmons by introducing adjustable elements such as PIN diodes and varactor tubes, and further realizes real-time control of the amplitude and phase of electromagnetic waves. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 The artificial surface plasmon mode division multiplexing adjustable unit is shown in (a) and the details of the layered structure are shown in (b).

[0029] Figure 2 The equivalent circuit diagram of the artificial surface plasmon mode division multiplexing adjustable unit is shown in (a) and the equivalent circuit of the cross section is shown in (b).

[0030] Figure 3 Dispersion curves of tunable units for plasmon mode multiplexing on artificial surfaces. (a) Changing the even-mode capacitance Ce; (b) Changing the odd-mode capacitance Co.

[0031] Figure 4 This is a two-mode phase shifter based on artificial surface plasmons. (a) Schematic diagram of the three-dimensional structure; (b) Schematic diagram of the M1 layer structure; (c) Schematic diagram of the M2 layer structure; (d) Schematic diagram of the M3 layer structure.

[0032] Figure 5 Photographs of a two-mode phase shifter sample based on artificial surface plasmons. (a) Front view; (b) Back view.

[0033] Figure 6 The phase measurements of a two-mode phase shifter based on artificial surface plasmons are shown. (a) Even-mode phase variation with applied voltage; (b) Odd-mode phase variation with applied voltage; (c) Effect of even-mode control voltage Ve on odd-mode phase; (d) Effect of odd-mode control voltage Vo on even-mode phase. Detailed Implementation

[0034] The present invention will now be described in further detail with reference to the accompanying drawings.

[0035] The specific structure of the artificial surface plasmon mode multiplexing adjustable unit used in this invention is as follows: Figure 1 As shown, it consists of three metal layers sandwiching two dielectric layers;

[0036] The M1 layer adopts a traditional configuration with two open-circuit stubs loaded on the central strip. Two varactor diodes are symmetrically introduced in the gap between the two open-circuit stubs and the central strip to achieve dual mode control, and the capacitance values ​​of the two varactor diodes are made equal, i.e., Ce = Ce1 = Ce2.

[0037] The M2 layer adopts a defect structure design with a central slit to achieve efficient excitation of the odd mode. Two metal through holes are designed on both sides of the slit to connect the M2 and M3 layers, laying the foundation for controlling the odd mode.

[0038] For the odd mode, electric fields with opposite directions need to be provided on both sides of the central strip. Therefore, a microstrip-slot line coupling excitation method is adopted. The electromagnetic wave fed from the odd mode port #3 is coupled to the slot line through a circular patch, which further excites the odd mode on the dual-mode transmission structure.

[0039] Metal patches are placed at the positions of the two metal vias corresponding to those of layer M2 on layer M3, and a varactor diode is connected between the two metal patches to control the odd mode, and its capacitance is denoted as Co.

[0040] By partitioning the narrow-side center of the adjustable unit of the artificial surface plasmon mode multiplexing, the equivalent circuits and mode field patterns of the two modes are analyzed, and the dual-mode control mechanism is explored. Figure 2 As shown in (a).

[0041] In cross-sectional observation, the equivalent circuit of this unit can be represented as follows: Figure 2 (b) For even modes, the center of the long side of the unit cell can be equivalent to a magnetic wall. In this case, the magnetic wall is equivalent to an open circuit, and the electric field lines are parallel to the magnetic wall, pointing from the parallel open-circuit stub to the radio frequency ground. Its equivalent circuit is as follows: Figure 2 As shown in (c), since the varactor diode controlling the odd mode is located at the magnetic wall, changing the odd mode capacitance Co has no effect on the even mode. That is, the electromagnetic characteristics of the odd mode can be independently controlled by adjusting the odd mode control voltage. For the odd mode, the center of the long side of the unit can be equivalent to an electric wall. At this time, the electric wall is equivalent to a short circuit, and the electric field lines are perpendicular to the electric wall. The directions on both sides are opposite. On the left side, it points from the parallel open-circuit stub to the RF ground, and on the right side, it points from the RF ground to the parallel open-circuit stub. Its equivalent circuit is as follows: Figure 2 As shown in (d), since the varactor diode controlling the even mode is located on the parallel stub, changing the even mode capacitance Ce will affect the odd mode. That is, by adjusting the even mode control voltage, while controlling the electromagnetic characteristics of the even mode, it will also have a certain impact on the electromagnetic performance of the odd mode.

[0042] Simulation results of dispersion curves for tunable units of plasmonic modulus multiplexing on artificial surfaces are as follows: Figure 3 As shown, the dielectric substrates Sub1 and Sub2 are Rogers 5880 materials with thicknesses of 0.787 mm and 0.254 mm, respectively. The metal layers M1, M2, and M3 are all made of copper with a thickness of 0.036 mm. The structural parameters are set as follows: p = 4 mm, d = 4.2 mm, a = 2 mm, w = 1 mm, g = 0.12 mm, g2 = 2 mm, rv = 0.15 mm, wp = 0.5 mm. Keeping the odd-mode capacitance Co = 0.03 pF constant, the even-mode capacitance Ce is gradually increased from 0.03 pF to 0.23 pF. The cutoff frequency of the even-mode gradually decreases from 18.7 GHz to 12.4 GHz; simultaneously, the cutoff frequency of the odd-mode is affected, gradually decreasing from 19.8 GHz to 14 GHz. Figure 3 As shown in (a). Keeping the even-mode capacitance Ce = 0.03pF constant, the odd-mode capacitance Co is gradually increased from 0.03pF to 0.23pF. The cutoff frequency of the odd-mode gradually decreases from 19.8GHz to 11.8GHz, while the cutoff frequency of the even-mode remains constant at 18.7GHz. Figure 3 As shown in (b), the dispersion curve simulation results are consistent with the above analysis, proving the correctness of the equivalent circuit of the adjustable unit of the plasmonic modulus multiplexing of the artificial surface.

[0043] Based on the research on artificial surface plasmon mode division multiplexing units, a dual-mode phase shifter based on artificial surface plasmons can be constructed. A dual-mode independent control technology for artificial surface plasmon channels is proposed to realize the simultaneous transmission of even mode and odd mode under the same frequency and a single physical channel. Based on the control method after introducing semiconductor devices such as varactor diodes, the phase electromagnetic characteristics of the two modes can be independently controlled.

[0044] The specific structure of the dual-mode phase shifter based on artificial surface plasmons is as follows: Figure 4 As shown, it consists of three metal layers sandwiched with two dielectric layers. The dual-mode phase shifter based on artificial surface plasmons mainly includes three parts: a dual-mode transmission structure, a dual-mode excitation structure, and a DC control structure, which will be described in detail below.

[0045] The dual-mode transmission structure consists of n adjustable modal division multiplexing units of artificial surface plasmons with period p, with a total length of l1. It can ensure efficient and highly isolated transmission of the even and odd modes of artificial surface plasmons.

[0046] The dielectric substrates Sub1 and Sub2 are made of Rogers 5880 material with thicknesses of 0.787 mm and 0.254 mm, respectively. The metal layers M1, M2 and M3 are all made of copper with a thickness of 0.036 mm. The p = 4 mm and n = 10 are taken. The structural parameters are consistent with the above-mentioned artificial surface plasmon modulus multiplexing adjustable unit.

[0047] To achieve real-time control of both modes, a DC control structure was also designed. The even-mode state control region is responsible for the real-time control of the electromagnetic characteristics of the even-mode mode, and it includes two varactor diodes placed in the gap of layer M1 and symmetrical about the central strip, and a choke structure placed in layer M3.

[0048] The choke structure employs a parallel sector capacitor design. By adjusting the radius of the sector capacitor and its distance from the feed position, its operating frequency band can be changed, effectively preventing radio frequency signals from entering the DC path and causing crosstalk. The upper and lower parallel stub terminals are connected to the choke structure on the M3 layer via metal vias, passing through the defect ground of the M2 layer, and communicating with the metal patch on which the DC voltage V1 is applied.

[0049] Therefore, by applying a DC voltage V1 to the metal patch of the M3 layer and a DC voltage V2 to the center strip, a dual-mode control voltage Ve = V1 – V2 can be applied across the varactor diode of the M1 layer, thereby controlling the dual-mode capacitance Ce.

[0050] The odd-mode state control region is responsible for the real-time control of the electromagnetic characteristics of the odd-mode. Its core component is a varactor diode connected across the metal ground of the M2 layer through a metal via on the M3 layer. The metal ground of the M2 layer is divided into upper and lower parts by a long gap. A DC voltage V3 is applied to the upper part of the metal ground and a DC voltage V4 is applied to the lower part of the metal ground. This allows the odd-mode control voltage Vo = V3 – V4 to be applied across the varactor diode of the M3 layer, thereby controlling the odd-mode capacitor Co.

[0051] To ensure RF path continuity, an RF connectivity region was created on the long gap in the M2 layer, using six 2pF capacitors to prevent the impact of cutting the metal ground on the X-band RF signal. Furthermore, as... Figure 4 As shown in (c), the long slot design incorporates a bent section, which not only adjusts the coupling excitation efficiency but also provides a soldering position for the RF SMA connector. Changing the odd-mode capacitor Co can independently control the electromagnetic characteristics of the odd-mode, but changing the even-mode capacitor Ce, while controlling the electromagnetic characteristics of the even-mode, will affect the odd-mode.

[0052] exist Figure 4 (b) It can be seen that the microstrip port of the even mode is directly connected to both sides of the dual-mode transmission structure;

[0053] exist Figure 4 (d) As can be seen, the odd mode is indirectly excited by microstrip-slot line coupling, with the two microstrip ports on the back of the base plate. Figure 4 (c) The groove lines can be seen.

[0054] To achieve independent control of even-mode and odd-mode, a compensation method targeting the electromagnetic characteristics of the odd-mode is required. This involves first changing the even-mode control voltage to regulate its electromagnetic characteristics; then changing the odd-mode control voltage to restore the electromagnetic state of the odd-mode; and finally, further changing the odd-mode control voltage to regulate its electromagnetic characteristics. The entire process achieves independent control of the electromagnetic characteristics of the two modes by adjusting the combination of even-mode and odd-mode control voltages (Ve, Vo).

[0055] To verify the electromagnetic performance of a two-mode phase shifter based on artificial surface plasmons, a PCB fabrication sample was prepared and experimentally verified. Sample photos are shown below. Figure 5 As shown. Ports #1 to #4 are designed with adapters for easy connection to solderless fixtures. The measured results of the transmission coefficient phase of the dual-mode phase shifter based on artificial surface plasmon resonances at a center frequency of 10 GHz are shown below. Figure 6 As shown in (ab), it can be seen that by changing the combination of even-mode control voltage and odd-mode control voltage (Ve, Vo), the phases of even-mode transmission coefficient S21 and odd-mode transmission coefficient S43 can be continuously varied within a range of 360°. Figure 6(c) shows the effect of changing the even-mode control voltage Ve on the odd-mode phase. It can be seen that when the even-mode phase shift increases from 0° to 180°, the odd-mode phase shift increases from 0° to 48°. However, by adjusting the odd-mode control voltage Vo, the odd-mode phase shift can be restored to 0°, which is equivalent to having no effect on the odd-mode. Figure 6 (d) illustrates the effect of changing the odd-mode control voltage Vo on the even-mode phase. It shows that when the odd-mode phase shift increases from 0° to 180°, the even-mode phase shift remains unchanged at 0°, meaning it has no effect on the even mode. These results demonstrate the independent continuous phase modulation capability of the dual-mode phase shifter based on artificial surface plasmons (ASPs) under simultaneous transmission at the same frequency for both modes. They also prove the effectiveness of ASP-based signal mode-division multiplexing technology.

Claims

1. A dual-mode phase shifter based on artificial surface plasmons, characterized in that, This includes dual-mode transmission structure, dual-mode excitation structure, and DC control structure; The dual-mode transmission structure consists of n adjustable artificial surface plasmonic mode-division multiplexing units with a period of p, used to simultaneously transmit even-mode and odd-mode modes in a single physical channel; the dual-mode excitation structure ensures the excitation effect of both even-mode and odd-mode modes, with even-mode being directly excited by microstrip ports and odd-mode being indirectly excited by microstrip-slotline coupling; the DC control structure realizes real-time control of the two modes of the dual-mode transmission structure.

2. The dual-mode phase shifter based on artificial surface plasmons according to claim 1, characterized in that, The artificial surface plasmon mode multiplexing adjustable unit includes three metal layers: M1, M2 and M3. Between the metal layers are two dielectric layers, and the width of each metal layer and dielectric layer is p.

3. A dual-mode phase shifter based on artificial surface plasmons according to claim 2, characterized in that, In the three metal layers: On layer M1, a central strip is provided through its width direction, and two open-circuit branches are symmetrically arranged on both sides of the central strip along its length direction. A gap is left between the central strip and the open-circuit branches. Two varactor diodes are symmetrically introduced into the gap for connection to realize the control of the dual mode, and the capacitance values ​​of the two varactor diodes are equal. On layer M2, a gap is opened through the center along its width direction to realize the excitation of odd mode. Two metal through holes are designed on both sides of the gap along its length direction. The metal through holes are used to connect layer M2 and layer M3. On the M3 layer, metal patches are placed at positions corresponding to the two metal vias, and a varactor diode is connected between the two metal patches to control the odd mode.

4. A dual-mode phase shifter based on artificial surface plasmons according to claim 1, characterized in that, The microstrip port of the even mode is directly connected to both sides of the dual-mode transmission structure; The odd mode is indirectly excited by microstrip-slot line coupling, with two microstrip ports on the back of the base plate.

5. A dual-mode phase shifter based on artificial surface plasmons according to claim 4, characterized in that, The DC control structure is divided into an even-mode state control region and an odd-mode state control region. The even-mode state control region is responsible for the real-time control of the electromagnetic characteristics of the even-mode mode, including two varactor diodes of the dual-mode transmission structure placed in the gap of layer M1 and symmetrical about the center strip, and a choke structure placed in layer M3.

6. A dual-mode phase shifter based on artificial surface plasmons according to claim 5, characterized in that, The choke structure adopts a parallel fan-shaped capacitor design, and its operating frequency band can be changed by adjusting the radius of the fan-shaped capacitor and its distance from the feed position. The upper and lower parts of the parallel stub terminal are respectively connected to the choke structure of the M3 layer through metal through-holes, passing through the M2 layer, and connected to the metal patch that applies DC voltage V1.

7. A dual-mode phase shifter based on artificial surface plasmons according to claim 6, characterized in that, By applying a DC voltage V1 to the metal patch of layer M3 and a DC voltage V2 to the center strip, a dipole-mode control voltage Ve = V1 – V2 is applied across the varactor diode of layer M1, thereby controlling the dipole-mode capacitance Ce.

8. A dual-mode phase shifter based on artificial surface plasmons according to claim 7, characterized in that, The odd-mode state control region is responsible for the real-time control of the electromagnetic characteristics of the odd-mode. The varactor diodes on both sides of the metal ground of the M2 layer are connected across the M3 layer through metal vias. The metal ground of the M2 layer is divided into upper and lower parts by a long gap. A DC voltage V3 is applied to the upper part of the metal ground and a DC voltage V4 is applied to the lower part of the metal ground. An odd-mode control voltage Vo = V3 – V4 is applied across the varactor diodes of the M3 layer, thereby controlling the odd-mode capacitor Co. An RF connectivity area is set on the long slot of the M2 layer. The long slot is designed with a bend to adjust the coupling excitation efficiency while reserving a soldering position for the RF SMA connector.

9. A dual-mode phase shifter based on artificial surface plasmons according to claim 8, characterized in that, A compensation method targeting the electromagnetic characteristics of the odd mode is adopted. In the control process, the even mode control voltage is changed first to regulate the electromagnetic characteristics of the even mode; then the odd mode control voltage is changed to restore the electromagnetic state of the odd mode; finally, the odd mode control voltage is further changed to regulate the electromagnetic characteristics of the odd mode. The whole process achieves independent regulation of the electromagnetic characteristics of the two modes by adjusting the combination (Ve, Vo) of the even mode control voltage and the odd mode control voltage.

10. A dual-mode phase shifter based on artificial surface plasmons according to claim 1, characterized in that, The odd mode of the dual-mode excitation structure provides electric fields in opposite directions on both sides of the central strip. Electromagnetic waves fed from the odd mode port are coupled to the slot line through a circular patch, thus exciting the odd mode on the dual-mode transmission structure.

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