TU11/TU12 signal frame alignment and supervisory monitoring ASIC design

In this paper we will go over the functions required for TU unit switching and explain the design of TUSM(TU11/TU12 frame alignment and supervisory monitoring) which executes these functions. VC3 signal termination, TUT11/TU12 signal frame alignment and supervisory monitoring function are essential to execute the TU11/TU12 unit switching in the BDCS (Broadband Digital Cross-connect System) with the 50 M/150 M level and 1.5 M/2 M level cross-connection function. The connection rate of the chip is set to 19.44 Mb/s and it is designed to have signal release/forming, de-multiplexing/muitiplexing of 7 TUG2, frame alignment of 28 TU11 or 21 TU12, VC11/VC12 signal path monitoring function and the monitoring function of signal connection located at the pre/post time switch.