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

Intra-symbol Multipath Interference Elimination Method for Underwater Acoustic Orthogonal Frequency Division Multiplexing System

An orthogonal frequency division and system symbol technology, which is applied in the field of multipath interference elimination in underwater acoustic OFDM system symbols, can solve the problems of inaccurate channel estimation and failure to consider the influence of cyclic prefix multipath interference, etc. Achieve good performance, eliminate multipath interference, and significantly improve performance

Active Publication Date: 2017-03-08
XIAMEN UNIV
View PDF3 Cites 1 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, in the existing channel estimation, only the multipath interference effect of the symbol itself is considered, and the influence of the multipath interference caused by the cyclic prefix on the symbol itself is not considered, and the channel estimation is not accurate. Therefore, what measures can be taken to reduce the cyclic Elimination of multipath interference within the symbol caused by the prefix and improving the performance of the bit error rate of the system are the key of the present invention

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
  • Intra-symbol Multipath Interference Elimination Method for Underwater Acoustic Orthogonal Frequency Division Multiplexing System
  • Intra-symbol Multipath Interference Elimination Method for Underwater Acoustic Orthogonal Frequency Division Multiplexing System
  • Intra-symbol Multipath Interference Elimination Method for Underwater Acoustic Orthogonal Frequency Division Multiplexing System

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0041] In order to make the object, technical solution and advantages of the present invention clearer, the present invention will be further described below in combination with specific embodiments and with reference to the accompanying drawings.

[0042] The present invention considers a cyclic prefix-based Orthogonal Frequency Division Multiplexing (OFDM) communication system, the block diagram of which is as follows figure 1 As shown, at the sending end of the comb-pilot-based OFDM system, the total number of subcarriers in each OFDM symbol is N, and M pilot symbols are inserted, and these M pilot symbols occupy the corresponding M subchannels , where L=N / M, that is to say every L-1 data sub-channel inserts a pilot symbol, X p (m) is the value of the inserted mth pilot symbol, X D (m) is the inserted useful data symbol, and X(k) is the data in the OFDM symbol. The original bit information sent is evenly inserted into the pilot after QPSK modulation, and the frequency do...

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 a method for eliminating multipath interference in a system symbol in an underwater sound orthogonal frequency-division multiplexing system, and relates to underwater sound wireless communication. The method includes the step of underwater sound orthogonal frequency-division multiplexing communication system transmitting end signal processing and the step of underwater sound orthogonal frequency-division multiplexing communication system receiving end signal processing. The transmitting end signal processing is achieved through the steps of conducting quadrature phase shift keying symbol mapping and serial-parallel conversion on sent bit information, inserting comb-type pilot frequencies in a parallel signal, conducting OFDM on signals inserted into the pilot frequencies, adding cyclic prefixes, conducting digital to analog conversion on the signals, and conducting up-conversion sending, wherein the number of the pilot frequencies is smaller than the total number of subcarriers. The receiving end signal processing is achieved through the steps of conducting down-conversion and analog to digital conversion on the received signals, conducting serial-parallel conversion and OFDM on the signals, conducting channel estimation based on compressed sensing, conducting multi-path interference elimination on an estimated data set (ap, taup), and judging and outputting the signals where interference elimination is conducted through decoding, wherein ap is the amplitude value of each path, and taup is the time delay of each path.

Description

technical field [0001] The invention relates to underwater acoustic wireless communication, in particular to a method for eliminating multipath interference within a symbol of an underwater acoustic orthogonal frequency division multiplexing system based on compressed sensing theory. Background technique [0002] Underwater sound is an underwater wireless long-distance communication transmission means. Multi-carrier communication is an effective means to realize high-speed underwater acoustic communication. The most important obstacle in high-speed underwater acoustic communication is mutual symbol interference caused by random multipath interference. Orthogonal frequency division multiplexing is a special multi-carrier modulation method. Its main advantages are strong anti-multipath interference ability, high transmission rate, and full utilization of the frequency band width. This technology has been successfully applied in many fields, such as asymmetric digital subscrib...

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 Patents(China)
IPC IPC(8): H04L27/26H04B13/02
Inventor 孙海信蒯小燕齐洁
Owner XIAMEN UNIV
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