Michael C Leung

US Patent:

6553541, Apr 22, 2003

Filed:

Apr 5, 2000

Appl. No.:

09/544241

Inventors:

Borivoje Nikolic - Berkeley CA
Leo Fu - San Jose CA
Michael Leung - Sunnyvale CA
Vojin G. Oklobdzija - Berkeley CA
Richard Yamasaki - late of Torrance CA

Assignee:

Texas Instruments Incorporated - Dallas TX

International Classification:

H03M 1341

US Classification:

714795, 360 40

Abstract:

Reduction of the complexity of a Viterbi-type sequence detector is disclosed. It was based on elimination of less probably taken branches in the trellis. The method is applied to the design of the E PR4 channel with 8/9 rate sliding block trellis code. Coding, by itself eliminates two states by coding constraints, and the disclosed method reduces the number of required ACS units from 14 to 11, while reducing their complexity as well. For the implementation of E PR4 detection, 4 4-way, 3 3-way, 3 2-way and one 1-way ACSs are needed. System simulations show no BER performance drop at common SNRs when compared with a full 16-state E PR4 implementation in magnetic disk drives.