Underwater acoustic communication method and system based on orbital angular momentum multiplexing technology

A technology of orbital angular momentum and underwater acoustic communication, applied in ultrasonic/sonic/infrasonic transmission systems, transmission systems, electrical components, etc. The rate cannot meet the requirements, etc., to achieve the effect of improving channel capacity and transmission rate

Active Publication Date: 2018-09-28
INST OF ACOUSTICS CHINESE ACAD OF SCI
View PDF3 Cites 9 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Due to the inherent low-frequency barriers of underwater acoustic long-distance communication, and its available frequency band is very limited, even if advanced modulation formats are used, the communication rate is still far from meeting the requirements. Therefore, channel multiplexing technology must be combined to improve channel capacity. For example, Orthogonal Frequency Division Multiplexing (OFDM) is currently being studied. However, because the transmitted signal of OFDM is formed by the superposition of transmitted signals on many mutually orthogonal subcarriers, the OFDM system is vulnerable to Doppler frequency. Due to the inherent low-frequency narrow bandwidth limitation of long-distance underwater acoustic communication, the number of subcarriers available for OFDM in the communication frequency band is very limited

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
  • Underwater acoustic communication method and system based on orbital angular momentum multiplexing technology
  • Underwater acoustic communication method and system based on orbital angular momentum multiplexing technology
  • Underwater acoustic communication method and system based on orbital angular momentum multiplexing technology

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0034] This embodiment proposes an underwater acoustic communication method based on orbital angular momentum multiplexing technology, which is used as an example for real-time transmission of video images.

[0035] The acoustic vortex field with a spiral phase can carry orbital angular momentum. In the vortex field, the sound wave will be twisted along its axis during the traveling process, forming a shape similar to a corkscrew. For details, see figure 1 , which is a schematic diagram of the wavefront shape of the vortex beam when the topological charge l is different. This twist causes the waves on the axis to cancel each other out, creating a center with zero field strength. If the vortex beam is projected onto a flat surface, the acoustic vortex will look like a ring with a "black" area in the center with no sound pressure. The propagation phase of the vortex sound beam has a spiral relationship with its zero field strength center, which can be written mathematically as ...

Embodiment 2

[0056] This embodiment proposes an underwater acoustic communication system based on orbital angular momentum multiplexing technology, including the following modules:

[0057] a module for applying an excitation signal to each array element in the sound source array;

[0058] A module for modulating the excitation signal in each subchannel to obtain a modulated array element driving signal carrying baseband digital information in each subchannel;

[0059] A module for channel-multiplexing the modulated array element drive signal carrying baseband digital information, and driving the sound source array to generate a channel-multiplexed OAM helical sound field;

[0060] A module for receiving the OAM spiral sound field signal and performing demultiplexing processing on the received signal to obtain subchannel information loaded on each independent OAM topology load;

[0061] A module for demodulating the demultiplexed information to obtain the original digital baseband signal....

Embodiment 3

[0065] see Figure 5 , this embodiment proposes an underwater acoustic communication system, including:

[0066] The sound source processor is used to apply an excitation signal to each array element in the sound source array, and modulate the excitation signal in each sub-channel to obtain a modulated array element carrying baseband digital information in each sub-channel An element driving signal, performing channel multiplexing on the modulated array element driving signal carrying the baseband digital information, driving the sound source array to generate an OAM spiral sound field after channel multiplexing;

[0067] sound source array,

[0068] sound field receiving array,

[0069] The receiver processor is configured to perform demultiplexing processing on the OAM spiral sound field signal received by the sound field receiving array, so as to obtain subchannel information loaded on each independent OAM topology charge, and demultiplex the demultiplexed information tu...

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 underwater acoustic communication method and system based on an orbital angular momentum multiplexing technology. The method comprises the following steps of applying an excitation signal to each array element in a sound source array; modulating the excitation signal in each sub-channel in order to obtain a modulated array element driving signal carrying baseband digitalinformation in each sub-channel; carrying out channel multiplexing on the modulated array element driving signal carrying the baseband digital information, and driving the sound source array to generate an OAM spiral sound field after channel multiplexing; receiving an OAM spiral sound field signal, and carrying demultiplexing processing on the received signal in order to obtain sub-channel information loaded on each independent OAM topological charge; and demodulating the information after demultiplexing in order to obtain an original digital baseband signal. According to the method, the channel capacity and the transmission rate of communication transmission based on underwater sound waves are greatly improved.

Description

technical field [0001] The present application relates to the technical field of underwater acoustic communication, in particular to an underwater acoustic communication method and system based on orbital angular momentum multiplexing technology. Background technique [0002] The ocean has a vast space and a large number of resources. At the same time, changes in the ocean environment pose a huge threat to human property safety. The development and utilization of ocean resources and the monitoring and early warning of the ocean environment are inseparable from real-time and reliable underwater communication technology. However, Due to the inherent high loss characteristics of electromagnetic or light waves in water, it is difficult to carry out long-distance high-speed communication like in the air. As far as the currently known forms of energy radiation are concerned, the attenuation of sound waves in water is small, and it is an underwater wireless communication technology....

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
Patent Type & Authority Applications(China)
IPC IPC(8): H04B11/00H04B13/02
CPCH04B11/00H04B13/02
Inventor 张晗杨军毕宏振王目光
Owner INST OF ACOUSTICS CHINESE ACAD OF SCI
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products