Digital multiplexing system

Abstract

In the field of digital data multiplexing systems, the master rates assigned to the different channels are defined by the national Telecommunications Authorities. It may and actually does happen that the master rates differ in different countries. A direct bit per bit multiplexing system from a first low master rate to a second high master rate is proposed which allows demultiplexing the high-rate digital signal into intermediate-rate signals. The number of the synchro and stuffing bits in the high-rate signal and intermediate-rate signals being known, only the low-rate signals are stuffed in dependence upon the difference between their own timing and the local timing at the multiplexing station. Blank intervals are provided in the low-rate signals having the duration of the synchro and stuffing bits in the intermediate-rate signals divided by the intermediate-to-low rate ratio and blank intervals are provided in the intermediate-rate signals having the duration of the synchro and stuffing bits in the high-rate signal divided by the high-to-intermediate rate ratio. Synchro and stuffing bits are inserted in the intervals resulting from the bit per bit multiplexing of the blank intervals.