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

Method for identifying OFDM (orthogonal frequency division multiplexing)-based distorted communication signals under QAM (quadrature amplitude modulation)

An identification method and communication signal technology, applied in the field of mobile communication, can solve the problems of increasing the circuit complexity of the receiving end, failing to obtain effects, phase and amplitude distortion, etc., and achieve excellent judgment and identification performance, simplified structure, and small calculation amount Effect

Inactive Publication Date: 2014-10-01
UNIV OF ELECTRONICS SCI & TECH OF CHINA
View PDF4 Cites 12 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0016] In the formula, 0≤k≤N-1, W(k) is the FFT transformation of Gaussian white noise w(n), it can be seen from formula (6) that the multipath channel causes phase and amplitude distortion to the signal, The carrier phase offset will cause the sample points of the received constellation to rotate, and the basic channel estimation (frequency domain least square method, LS) or equalization algorithm can compensate the signal distortion to a certain extent, but cannot obtain better results
In order to solve the above problems, the existing methods are mainly to improve the channel estimation algorithm or improve the channel equalization algorithm, but these methods will increase the complexity of the receiving end circuit to a certain extent

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
  • Method for identifying OFDM (orthogonal frequency division multiplexing)-based distorted communication signals under QAM (quadrature amplitude modulation)
  • Method for identifying OFDM (orthogonal frequency division multiplexing)-based distorted communication signals under QAM (quadrature amplitude modulation)
  • Method for identifying OFDM (orthogonal frequency division multiplexing)-based distorted communication signals under QAM (quadrature amplitude modulation)

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0036] Describe technical scheme of the present invention in further detail below in conjunction with accompanying drawing: as figure 1 As shown, a distorted communication signal identification method based on OFDM QAM modulation is characterized in that: it includes the steps of adding training symbols at the sending end and distorted signal identification steps at the receiving end, wherein the adding of training symbols at the sending end includes the following Substeps:

[0037] S11, sequentially performing QAM modulation, serial / parallel conversion and IFFT inverse fast Fourier transform on the data to be sent;

[0038] S12, adding a cyclic prefix and a training sequence to the data obtained after processing in step S11:

[0039] S13, sequentially perform parallel / serial conversion, I / Q modulation and digital-to-analog conversion on the data added with the cyclic prefix and the training sequence, and transmit through the wireless channel;

[0040] The distorted signal d...

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 discloses a method for identifying OFDM (orthogonal frequency division multiplexing)-based distorted communication signals under QAM (quadrature amplitude modulation). The method comprises steps of training symbol addition at a sending end and distinguishing of distorted signals at a receiving end. According to the method, the structure of a receiver under a flat Rayleigh fading channel is simplified, the receiver is not required to use channel estimation and channel equalization modules, improvement of initial cluster centroids is performed on the conventional k-means clustering algorithm by using pilot signals which are then applied to distinguishing and identifying of the distorted communication signals, so that the method has the characteristics of few iteration times, small calculated amount and the like, and has better distinguishing and identifying performance on signal phase distortion and amplitude distortion.

Description

technical field [0001] The invention belongs to the technical field of mobile communication, and in particular relates to a signal clustering identification method of an Orthogonal Frequency Division Multiplexing (OFDM)-based Orthogonal Amplitude Modulation (QAM) system under a multipath fading channel. Background technique [0002] Orthogonal Frequency Division Multiplexing (OFDM) is a multi-carrier multiplexing modulation technology, which divides the high-bit-rate serial data stream to realize low-rate multi-state data symbols to modulate the corresponding sub- Carrier, so as to realize the parallel transmission of data. Since its sub-carriers are mutually orthogonal, overlapping of the frequency spectrum is allowed, which improves the spectrum utilization to a large extent and reduces the mutual interference between sub-carriers. Therefore, in modern It is widely used in communication. [0003] For wireless communication, when the message signal arrives at the receivin...

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): H04L27/36H04L27/38
Inventor 彭军蒲宇亮黄乐天郭志勇
Owner UNIV OF ELECTRONICS SCI & TECH OF CHINA
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