Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Improved SPGD algorithm for OAM beam phase repair

An improved algorithm and phase technology, applied in the field of adaptive optics, to reduce system cost, meet real-time requirements, and improve convergence speed

Inactive Publication Date: 2018-04-10
BEIJING UNIV OF POSTS & TELECOMM
View PDF2 Cites 4 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to provide a kind of improved SPGD algorithm for OAM light beam restoration for existing adaptive optics system without wavefront sensor

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Improved SPGD algorithm for OAM beam phase repair
  • Improved SPGD algorithm for OAM beam phase repair
  • Improved SPGD algorithm for OAM beam phase repair

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0013] In order to make the object, technical solution and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and examples.

[0014] In order to illustrate this improved algorithm, the system adopted in this specific embodiment is now described, and the system block diagram of this specific embodiment is as follows figure 1 shown. This system adopts the probe system in the wavefront sensorless adaptive optics system, uses the Gaussian beam as the probe beam, after the Gaussian beam is expanded at the sending end, it is polarized multiplexed with the OAM beam carrying information, and passes through the coaxial Atmospheric Turbulent Channel Transmission. At the receiving end, a polarizing beam splitter is used to separate the two beams, a lens is used to perform Fourier transform on the probe beam, an infrared camera is used to detect the light intensity of the probe beam, and...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

The invention provides an improved SPGD algorithm for OAM beam phase repair. The algorithm operation mode is characterized by setting an initial Zernike coefficient an initial deformation mirror voltage at a receiving end, and setting a voltage disturbance value and a Zernike coefficient disturbance value meeting Bernoulli distribution; generating disturbance phases through a zone method (Z-SPGD)and a modal method (M-SPGD) respectively; adding the disturbance phases generated through the two algorithms to obtain a total disturbance phase of the improved algorithm; calculating a deformation mirror brake voltage corresponding to the total disturbance phase; controlling surface type of a deformation mirror through the voltage to repair the beam, and measuring performance indexes of the beam;calculating the Zernike coefficient in M-SPGD and the deformation mirror voltage in the Z-SPGD in the next iteration by utilizing the performance indexes; and repeating the iteration steps until reaching algorithm convergence, and outputting a voltage value. The repair method can reduce resolution requirements of the M-SPGD for the deformation mirror and meanwhile, can improve convergence speed effectively, thereby solving the problem of slow convergence speed of the Z-SPGD and facilitating meeting real-time demand of an OAM communication system.

Description

technical field [0001] The present invention relates to adaptive optics technology, and in particular, the present invention relates to an improved stochastic parallel-gradient-descent algorithm for orbital angular momentum beam repair. Background technique [0002] OAM multiplexing has gained widespread attention in optical communication technology. The beam carrying OAM has an exp(ilθ) spiral phase form, where l is the topological charge of the OAM beam, and θ is the azimuth angle. The OAM beams with different l values ​​are orthogonal to each other, which provides a good prerequisite for the multiplexing and demultiplexing of OAM beams. In the OAM multiplexing technology, each signal carries independent data information, which can expand the capacity of free-space optical communication (free-space optical communication) and increase spectral efficiency. At present, there have been experimental reports on short-distance weakly turbulent free-space optical systems using OA...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
IPC IPC(8): G02B27/00G06F17/10
CPCG02B27/0012G06F17/10
Inventor 尹霄丽林娇玲常欢崔小舟张丽佳忻向军王拥军张琦田清华饶岚李莉田凤
Owner BEIJING UNIV OF POSTS & TELECOMM
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com