Differential Pattern time delay shift coding underwater acoustic communication method for based on parametric array

Abstract

The invention relates to the field of underwater acoustic communication, in particular to a differential Pattern time delay shift coding underwater acoustic communication method for based on a parametric array. The method comprises the following steps of generating preformed Pattern code signals and a preformed synchronizing signal by adopting parametric pre-modulation, wherein one group of the preformed Pattern code signals are produced for modulation and call of a differential time delay difference; carrying out channel coding on information source information, quantizing and mapping the coding information to a time delay value, modulating the time delay value on the time delay difference between the preformed Pattern code signals, when the length of a communication signal reaches one frame, packaging the frame of signal and adding the preformed synchronizing signal; and emitting the signal through the parametric array after power amplification. Through the narrow directional property of difference frequency sound wave generated by parametric emission, the frequency for reflecting the sound wave in an interface can be reduced, and the inter-symbol interference caused by multi-path extension is inhibited. Through the narrow directional property of difference frequency wave of the parametric matrix, the risk of exposure of an emission node is reduced, and concealment and confidentiality of communication are improved.

Description

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

AI Technical Summary

Benefits of technology

This invention relates to an improved method for prevention or reduction of interference between signals during underwater communications due to multipath propagation. It uses specific sounds that generate lower frequencies than usual but have wider directivities compared to previous methods like sonar techniques. These differences help improve signal quality while reducing noise from other sources such as ships' movements. Additionally, this technique does away with any changes made over long distances without affecting their effectiveness at short range depths.

Problems solved by technology

This patented technical problem addressed in this patents relates to finding an efficient way to transmit data over both submerged acousic communications systems and differential patterns delays between them without compromising their security or privacy capabilities.

Images