A Method of Helix Spectrum Analysis of Vortex Beams Based on Loop Integral

Abstract

The invention discloses a vortex beam helical spectrum analysis method based on loop integral, which belongs to the field of electromagnetic vortex. The method comprises the following steps: 1) determining the loop integral radius for loop integral helical spectrum analysis; 2) determining the key parameters for obtaining the value of the loop integral radius according to the expression characteristics of the loop integral radius, including: torus distance, beam waist radius, coherence 3) After determining the value of the integral radius of the loop, the phase distribution, OAM order, amplitude distribution, and power distribution on the closed loop are obtained according to the vortex wave field distribution; 4) Determine the harmonics of each order on the closed loop Helical Spectrum Distribution. It can be equivalent to the traditional helical spectrum analysis method, solve the problem of a large number of discrete harmonic points of each order on the receiving plane, and effectively reduce the complex calculation amount of the traditional helical spectrum component calculation under the same quality evaluation performance, which is helpful for in-depth understanding The essence of vortex beam helical spectrum analysis.

Description

technical field [0001] The invention belongs to the field of electromagnetic vortex, in particular to a method for analyzing the helical spectrum of a vortex beam based on loop integration in a microwave frequency band. Background technique [0002] The angular momentum carried by electromagnetic waves is divided into spin angular momentum and orbital angular momentum. The vortex beam is a kind of electromagnetic wave carrying orbital angular momentum. It is an annular beam with zero axial intensity in the propagation direction and a phase with a spiral rising or falling gradient distribution. Its expression changes with the cylindrical coordinate azimuth φ Spiral phase factor e ilφ . [0003] The research on electromagnetic orbital angular momentum was first carried out at optical frequency. After that, the experiment of using radio frequency OAM wave for data transmission shows that the multiplexing based on OAM mode can greatly improve the utilization rate of wireless ...

AI Technical Summary

Problems solved by technology

The spiral spectrum analysis method is based on the area integral of harmonic energy on the receiving plane. Due to the large number of discrete points of each OAM mode harmonic on the plane, it is difficult to process and computationally complex in practical applications.

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