Unlock instant, AI-driven research and patent intelligence for your innovation.

Method and apparatus for estimating frequency offset in mobile communications system

A wireless communication system and frequency offset technology, applied in the transmission system, multi-carrier system, multiplexing communication, etc., can solve the problems of low precision of phase value, complex generation of frame array reference code, and quantity limitation

Inactive Publication Date: 2007-06-13
LG ELECTRONICS INC
View PDF1 Cites 9 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Thus, generating the frame array and the reference code can become complex
Thus, secondly, if the starting point is not accurately determined, the conventional frequency offset estimation method may become less reliable
Third, the phase difference due to the frequency offset between chips is very small, so there is a limit to the number of bits that can actually be used
Therefore, performance suffers from complexity caused by the small precision with which the phase values ​​can be represented

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 and apparatus for estimating frequency offset in mobile communications system
  • Method and apparatus for estimating frequency offset in mobile communications system
  • Method and apparatus for estimating frequency offset in mobile communications system

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0023] Reference will now be made in detail to the preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts.

[0024] In receiving the signal transmitted from the transmitting end, if there is no signal distortion (e.g., attenuation noise) or damage to the signal, the phase of the training sequence code received at the receiving end (e.g., MS) has a frequency proportional to the frequency offset slope. The phase of the training sequence code can be expressed in linear form according to Equation 1.

[0025] [equation 1]

[0026] θ(n)=2πf 0 nT+θ 0

[0027] Among them, θ 0 represents the specified phase offset at the burst start point, while f 0 Indicates the frequency offset.

[0028] Referring to this linear form, a least squares (LS) technique can be applied to estimate the frequency offset. Calculation of...

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

A method of estimating frequency offset in a code division multiple access (CDMA) wireless communication system is disclosed. More specifically, the method includes receiving a training sequence, wherein the training sequence is represented by a plurality of periodically repeated training symbols, acquiring each of a plurality of phase difference values using the received training symbols, wherein each phase difference value is obtained by comparing two training symbols which are received in a specified time distance, and obtaining the frequency offset using the acquired each of the plurality of the phase difference values.

Description

technical field [0001] This application claims the benefit of Korean Patent Application P10-2005-107035 filed on Nov. 9, 2005, which is incorporated herein by reference. Background technique [0002] The present invention relates to estimating frequency offset, and more particularly, to a method and device for estimating frequency offset in a wireless mobile communication system. [0003] The frequency offset can be defined by the frequency difference caused by part of the oscillator of the mobile station (MS) and the Doppler effect of the channel. Then, frequency synchronization is used to estimate the frequency offset and continuously compensate the frequency offset using the estimated frequency offset. However, at the receiving end, the frequency offset causes sampling errors, and the accumulation of the frequency offset results in deterioration of the receiving capability. [0004] A conventional Code Division Multiple Access (CDMA) system employing Frequency Division ...

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): H04B1/707H04J13/00H04L27/34H04B1/12
CPCH04L27/0014H04B1/7075H04B1/7073
Inventor 张峻
Owner LG ELECTRONICS INC