OFDM training symbol generation and synchronization method based on CAZAC sequence

A technology of training symbols and sequences, which is applied in the field of communication, can solve the problems of high complexity of OFDM training symbols and low synchronization accuracy, and achieve the effect of reducing the amount of calculation, reducing complexity, and fast synchronization

Active Publication Date: 2014-01-22
SHANGHAI NAT ENG RES CENT OF DIGITAL TELEVISION +1
View PDF4 Cites 27 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0006] The purpose of the present invention is to provide a method for generating OFDM training symbols based on CAZAC sequences, and a synchronization method utilizing such OFDM training symbols to improve the problem of high complexity of OFDM training symbols but low synchronization accuracy in the prior art

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
  • OFDM training symbol generation and synchronization method based on CAZAC sequence
  • OFDM training symbol generation and synchronization method based on CAZAC sequence
  • OFDM training symbol generation and synchronization method based on CAZAC sequence

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0035] The technical solutions of the present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0036] refer to figure 1 , the present invention is based on the OFDM training symbol of CAZAC sequence design and the synchronization process realization steps are as follows:

[0037] Step 1: Generate CAZAC sequence and its transformation sequence.

[0038] 1.1) The CAZAC sequence is a Zadoff-Chu sequence, and the expression is , where N=512, k=0, 1..., N-1, j is an ordinal unit, and r is a positive integer that is relatively prime to N;

[0039] 1.2) transform the sequence (with denoted) for the CAZAC sequence (use Indicates) and its shifted conjugate sequence (use Indicates the product of ), let the CAZAC sequence cyclically shifted by λ to be , transform sequence ;

[0040] 1.3) The system carries parameter information according to different r values ​​and λ values. The parameter information includes FFT s...

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 an OFDM training symbol generation method based on a CAZAC sequence, and a synchronization method utilizing a OFDM training symbol. The generation method comprises the following steps: the CAZAC sequence and a CAZAC shifting conjugation sequence are generated; the CAZAC sequence and the CAZAC shifting conjugation sequence are multiplied so that a conversion sequence is obtained; and the CAZAC sequence is multiplied by a fixed frequency deviation, and then is combined with the CAZAC sequence and the conversion sequence so that an OFDM training symbol is obtained. A training sequence is directly generated in a time domain by adopting the CAZAC and the conversion sequence thereof so that complexity is lowered. Sufficient parameter information, including size of FFT, size of guard intervals, an SISO / MISO mode and a discrete pilot frequency mode, is carried according to values of the CAZAC sequence and difference of circulation shifting points of the conversion sequence of the CAZAC sequence so that rear-end computing amount is reduced, and symbol timing, decimal times frequency deviation estimation and parameter demodulation are realized simultaneously, and thus the method is rapid in synchronization.

Description

technical field [0001] The invention belongs to the technical field of communication, and relates to an OFDM synchronous training symbol and a timing and frequency offset estimation method in a wireless communication system, which can be used in the OFDM system, especially a digital television broadcasting system. [0002] Background technique [0003] Orthogonal Frequency Division Multiplexing (OFDM) is an efficient modulation technique that can not only resist frequency selective fading, but also has high spectrum utilization, and has been widely used in wireless broadcasting standards such as DAB (Digital Audio Broadcasting, Digital Audio Broadcast), DVB-T (Digital Video Broadcast-Terrestrial), and the recently proposed second-generation standard DVB-T2 (second-generation terrestrial digital television broadcast). [0004] The disadvantage of OFDM is that it is very sensitive to timing deviation and frequency offset. If there is timing error in the system, it will cause ...

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): H04L27/26H04B7/08
Inventor 葛建华王丽华刘刚张文军管云峰
Owner SHANGHAI NAT ENG RES CENT OF DIGITAL TELEVISION
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