Artificial surface plasmon orbital angular momentum beam scanning antenna and method thereof

Abstract

The invention discloses an artificial surface plasmon orbital angular momentum beam scanning antenna and a method thereof. According to the invention, a waveguide feed device is adopted to convert a TEM mode in a coaxial line into an SSP mode, and the SSP mode is propagated along the surface of an SSP transmission line; under the diffraction effect of a radiation structure loaded outside the SSP transmission line, the wave vector of the SSP mode is superposed with the harmonic wave vector generated by diffraction to generate a frequency spectrum shifting effect, the SSP mode is converted intoa free space radiation wave, and meanwhile, the intrinsic electric field of a spiral line of the radiation structure has an OAM mode, thereby realizing the space radiation wave with the OAM mode, andworking in different frequency bands; the radiation direction of the OAM mode is controlled by controlling the working frequency; the rotation direction of the OAM mode is consistent with the chirality of the spiral line; the structure is compact, and a plurality of unit arrays are not needed; the robustness of the system is high, and only the spiral characteristic of the spiral line needs to be kept; and the waveguide feed device is simple, only coaxial port feed is needed, and a complex feed network is not needed.

Description

technical field [0001] The invention relates to orbital angular momentum technology, in particular to an artificial surface plasmon orbital angular momentum wave vector scanning antenna and a realization method thereof. Background technique [0002] Orbital angular momentum (OAM) has a spiral wave front and has a wide range of applications in various fields. First, different OAM modes are orthogonal to each other, which can be applied in communication systems to improve channel capacity. In addition, OAM can be applied in imaging, quantum communication and other fields. Due to the wide application of OAM in many fields, how to efficiently generate OAM patterns has always been a research hotspot. In the optical band, the thickness of the spiral phase plate is different in the angular direction. When the Gaussian mode passes through the spiral phase plate, it can be converted into an OAM mode. In addition, the conversion of the OAM mode can also be realized through a hologra...

AI Technical Summary

Problems solved by technology

Although there are many ways to generate OAM beams, there are still many problems, such as (1) limited working size, the use of an array structure will result in too large a volume, which is not conducive to the miniaturization of the antenna structure, and faces a complex feed structure Design; (2) limited operating bandwidth, due to the resonance effect of the metasurface structure depending on the unit structure, the bandwidth is narrow; (3) mode adjustment is difficult

Structures such as metasurface arrays, antenna arrays, and planar artificial surface plasmons depend on phase changes between adjacent units, and each OAM mode distribution requires a specific array arrangement, which is difficult to adjust; (4) Radiation The direction is difficult to adjust. At present, the adjustment methods to realize the radiation mode are limited, mainly mechanical adjustment, and the adjustment angle is limited

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