公开(公告)号：DE2559003A1

公开(公告)日：1976-07-08

申请号：DE2559003

申请日：1975-12-29

Applicant: IBM

Inventor： PARKER BRIAN EUGENE ,  WEST LYNN PARKER

IPC: H04J3/00 ,  H04B7/15 ,  H04B7/185 ,  H04B7/212 ,  H04J3/24 ,  H04M3/00 ,  H04Q11/00 ,  H04Q11/04 ,  H04J6/02 ,  H04B7/14

Abstract: Modular digital exchange terminals linked in a network by earth satellite provide coordinated multiplex switching and activity compression between line circuits and satellite time division channels. The line circuits carry digital data and digitalized voice telephone information into and out of the network. Nodal access modules (NAU's) interface to the satellite radio equipment. Branch exchange modules (NCU's) link line circuits switchably to a nodal access module through time division channels of subsidiary digital communication links. In transit up-link (to satellite time division channels) information is switched between lines and NCU buffer stores (virtual channels), selectively assigned by activity compression to time channels on associated digital links (each link accommodating only a fraction of the virtual traffic capacity of the associated stores), and transmitted to the NAU. In the NAU the activity compressed composite is time-concentrated with traffic of other digital links (in NAU buffer storage), and passed out on demand assigned satellite time division (traffic burst) channels. In downlink distribution to outlet line circuits the receiving NAU picks out from the interleaved network composite only the information channels destined for its outlet line circuits. These are stored, reordered in space/time associations with digital link time channels and activity compressed into associated digital link channels. The receiving NCU buffers and switches the information through associated internal (virtual) channels to respective outlet line circuits (destinations).