Method of and apparatus for noise whitening filtering

A technology of whitening filter and whitening filter, applied in digital transmission system, baseband system components, baseband system, etc., can solve problems such as inaccurate noise autocorrelation, complex equalizer 114, etc.

Inactive Publication Date: 2006-11-22
OPTIS WIRELESS TECH LLC
View PDF0 Cites 10 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0019] Even if the whitening filter block 110 is as short as a second-order FIR filter, the equalizer 114 would still be four times more complex due to the channel span extension
In addition, since the noise autocorrelation (especially the elements with large lags) is inaccurate due to the noise estimation error in the case of strong ACI, directly solving the Yule-Walker equation with or without stepwise recursion in the channel with strong adjacent channel interference not always optimal

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 of and apparatus for noise whitening filtering
  • Method of and apparatus for noise whitening filtering
  • Method of and apparatus for noise whitening filtering

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0027] To help explain the principles of the invention, the apparatus and method are presented in the context of a GSM mobile station. It is not intended to limit the scope of the invention to the examples given here. Those skilled in the art can also apply the principles of the present invention to numerous other types of communication systems.

[0028] figure 2 is a functional block diagram representing an exemplary explicit whitening process in accordance with the principles of the present invention. exist figure 2 Among them,  indicates a dependency relationship. figure 2 The variables shown in are as follows:

[0029] r Received signal

[0030] r" updated received signal

[0031] t training sequence

[0032] p sync position

[0033] updated sync position of p'

[0034] h {n} n-tap channel estimation

[0035] h {n} 'n-tap updated channel estimate

[0036] Δ′ normalized noise correlation

[0037] w {m+1} 'whitening filter coefficients

[0038] s'symbol e...

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 and apparatus for reducing interference in a received signal. A normalized noise correlate is determined (210) using the received signal and a first channel estimate (104) of the received signal. Conditional whitening-filter settings are determined (212) using the normalized noise correlate (210). A whitening filter (202) is applied to the received signal in accordance with the conditional whitening-filter settings (212). A synchronization adjustment of an updated received signal is performed (204). A second channel estimate, which is of the same span as the first channel estimate, is determined (206) using an updated synchronization position and the updated received signal.

Description

technical field [0001] The present invention relates generally to simplified whitening filtering in digital communication systems, and more particularly to noise whitening filtering in communication systems operating according to the Global System for Mobile Communications (GSM). Background technique [0002] Receiver performance in wireless digital time-division multiple access (TDMA) communication systems such as those operating in accordance with Global System for Mobile Communications (GSM), Enhanced Data for GSM Evolution (EGDE), and Digital Advanced Mobile Services (DAMPS) typically limited by interference. Interference may e.g. come from other users. Users operating on the same carrier frequency in adjacent cells may generate co-channel interference (CCI), while users operating on adjacent carrier frequencies may generate adjacent channel interference (ACI). [0003] ACI usually depends on interference from primary adjacent channels because receiver filters can effe...

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): H04L25/02
CPCH04L25/0212H04L25/0224H04L25/03993
Inventor 何首生
Owner OPTIS WIRELESS TECH LLC
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

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap