公开(公告)号：US3497830A

公开(公告)日：1970-02-24

申请号：US3497830D

申请日：1968-03-20

Applicant: BELL TELEPHONE LABOR INC

Inventor： COLTON JOHN R ,  SHEEHAN JOHN R ,  VACHON PATRICK A

IPC: G06G7/25 ,  H03C1/00 ,  H04L27/04 ,  H03K13/00 ,  H03F1/38 ,  H03K7/00

CPC classification number: H03M1/808 ,  G06G7/25 ,  H03C1/00 ,  H04L27/04

公开(公告)号：US3573622A

公开(公告)日：1971-04-06

申请号：US3573622D

申请日：1968-04-23

Applicant: BELL TELEPHONE LABOR INC

Inventor： HOLZMAN LOUIS N ,  SHEEHAN JOHN R

IPC: H03H9/02 ,  H04L25/48 ,  H04L25/497 ,  H04B1/66

CPC classification number: H04L25/497

Abstract: Theoretically maximum equivalent binary data transmission rates are obtainable in partial-response channels; i.e., bandlimited channels with filter shaping which disperses the impulse response to individual data inputs over more than one signaling interval. However, the resultant multilevel line signals occasionally give rise to system start-up problems. These problems are eliminated by initial sampling of alternate data input pairs for one particular partial-response format to produce a two-level line signal which preserves transitions occurring at the basic signaling interval. The same technique provides means for signaling at half the design rate without changing channel filters or the basic clock rate.

公开(公告)号：US3529290A

公开(公告)日：1970-09-15

申请号：US3529290D

申请日：1968-05-10

Applicant: BELL TELEPHONE LABOR INC

Inventor： SCHROEDER HENRY C ,  SHEEHAN JOHN R

IPC: H04L1/00 ,  H03M13/00 ,  H04L1/20 ,  H04L27/18 ,  H04L27/22 ,  H04L27/233 ,  G08C25/00 ,  H04L1/10

CPC classification number: H04L27/2331 ,  H04L1/206

公开(公告)号：US3508153A

公开(公告)日：1970-04-21

申请号：US3508153D

申请日：1967-09-11

Applicant: BELL TELEPHONE LABOR INC

Inventor： GERRISH ALLAN M ,  PORT ERICH ,  SHEEHAN JOHN R

IPC: H03H15/00 ,  H04B3/06 ,  H04L25/03 ,  H04B1/12 ,  H04B3/04

CPC classification number: H04L25/03038