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

Adaptive channel equalizer

An adaptive equalization and channel technology, applied in the field of communication systems, can solve problems such as changing signal correlation characteristics

Inactive Publication Date: 2002-04-03
NOKIA MOBILE PHONES LTD
View PDF1 Cites 2 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0010] However, most of the proposed adaptive interference suppression methods rely on the third-order stability of the signal at the symbol level
Unfortunately, this makes them unsuitable for systems using long scrambling codes, such as wideband code division multiple access, where the pseudo-random scrambling code changes the correlation properties of different symbols of the signal

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
  • Adaptive channel equalizer
  • Adaptive channel equalizer
  • Adaptive channel equalizer

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0028] As mentioned above, in the downlink of synchronous code division multiple access using orthogonal spreading codes, multiple access interference is basically caused by multipath channels. Therefore, multiple access interference can be suppressed by channel equalization, because the user's orthogonal signals are propagated to the receiver of interest through the same channel.

[0029] For channel equalization, please refer to "Wireless Channel Equalization" published by D.P.Taylor, G.M.Vivetta, B.D.Hart and A.Mammela in European Telecommunications Journal, Vol. 9, No. 2, pp. 117-143 in 1998.

[0030] Further reference may be made to "Downlink Channel Decorrelation in Code Division Multiple Access Systems with Long Codes", S. Werner and J. Lilleberg, IEEE Automotive Technology Conference VTC'99, May 1999. Also refer to "Adaptive Channel Equalization Based on Code Division Multiple Access Downlink Chip Separation" by P.Komulainen and M.J.Heikkila, IEEE International Persona...

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 receiver for a code division multiple access communication system is disclosed. Such a receiver comprises at least one antenna for receiving signals from a code division multiple access channel, an estimator for estimating said channel impulse response and an adaptive equalizer. This estimator provides a reference for the adaptive equalizer, which is used to estimate the transmitted chip sequence of this channel and restore the orthogonality between the received signals. The adaptive equalizer includes circuitry for estimating the sequence of chips transmitted by this channel using a blind adaptive algorithm.

Description

[0001] This application, filed March 3, 2000 by Petri Komulainen and Markku J. Heikkila, entitled "Adaptive Channel Equalizer," has Attorney Docket No. 872.8546USU US Patent Application 09 / Continuation-in-Part Application, with Express Mail Number: EL 470231293US, under 35 U.S.C. §119(e), which claims benefit from Petri Komulainen and Markku J. Heikkila, filed March 10, 1999, entitled "Adaptive Channel Equalizer priority of Provisional Patent Application No. 60 / 123,689. This provisional patent application is hereby incorporated by reference in its entirety. field of invention [0002] The present invention relates to a communication system, in particular to a receiver for performing adaptive channel equalization. Background of the invention [0003] The code division multiple access communication system is based on digital, broadband, and spread spectrum technology, which transmits multiple independent user signals in an allocated radio frequency band. In the CDMA system...

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): H04B1/707H04B1/712H04B3/06H04B7/005H04L25/03
CPCH04L2025/03375H04L2025/03509H04L25/03044H04L2025/03617
Inventor P·科穆莱宁M·海基莱
Owner NOKIA MOBILE PHONES LTD