Interleaver and deinterleaver for use in a diversity transmission communication system

Abstract

Apparatuses for a transmitter and a receiver which enhance the performance of a system utilizing interleaving and transmit diversity by reodering the sequence of symbols transmitted along the different transmission channels. This enhancement is accomplished by providing different shuffling functions in conjunction with the interleavers and deinterleavers used with different transmission channels, which decreases the probability of loss of sequential symbols when transmission channels or antennas become correlated.

Description

CLAIM OF PRIORITY UNDER 35 U.S.C. §120 [0001] The present application for patent is a continuation and claims priority to patent application Ser. No. 10 / 002,446 entitled “INTERLEAVER AND DEINTERLEAVER FOR USE IN A DIVERSITY TRANSMISSION COMMUNICATION SYSTEM” filed Oct. 22, 2001, allowed, which is a continuation of U.S. Pat. No. 6,356,528 and assigned to the assignee hereof and hereby expressly incorporated by reference herein.BACKGROUND OF THE INVENTION [0002] I. Field of the Invention [0003] The current invention relates to wireless telecommunications. More particularly, the present invention relates to a novel and improved transmitter design for enhancing the reliability of communications in a wireless communications system. [0004] II. Description of the Related Art [0005] The use of code division multiple access (CDMA) modulation techniques is one of several techniques for facilitating communications in which a large number of system users are present. Other multiple access commu...

AI Technical Summary

Benefits of technology

"The invention improves the performance of a system that uses interleaving and transmit diversity by reordering the sequence of symbols transmitted along different transmission channels. This helps prevent loss of symbols due to correlated fading in the two transmission channels. The invention splits the symbols into groups that are interleaved independently, and a shuffler is used to make sure that even if the different transmission paths from the different transmitters become correlated, the performance degradation is minimal. The shuffler cyclically rotates the symbols it receives to achieve the desired result. Overall, the invention enhances the reliability and performance of the system."

Problems solved by technology

A problem which can occur if the interleavers and splitter are not chosen correctly, or even worse if they are all identical, is that the performance will be severely degraded when the signals from the different transmitters go through channels that are correlated.

If traditional interleaving strategies are used, correlated fading will severely deteriorate performance.

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