Abstract: A converter operative in a digital telecommunication system to receive signals coded at a first compression mode and convert them into a second compression mode. The conversion provided, leads to substantially less impairments in the decompressed form of the signals converted into the second compression mode, had the signals received been decompressed from the first compression mode into their decompressed form followed by compressing these decompressed signals into the second compression mode, and decompressing the signals thus obtained.

Abstract: A telecommunications system including an at least partially digital telephone link having an analog end portion, first and second modems disposed along the link, and analog/digital devices disposed along the link intermediate the modems which are operative to support communications between the first and second modems substantially at bit rates in excess of 28.8 Kbps.

Abstract: A telecommunication system for interconnecting a plurality of telephone communication trunks to a transmission network, the system including transmission apparatus at a first end of the transmission network including apparatus for detecting facsimile signals on the plurality of telephone communication trunks, apparatus for demodulating the facsimile signals, apparatus for transmitting along the transmission network, in demodulated form, the facsimile signal output from the apparatus for demodulating, and receiving apparatus at a second end of the transmission network including apparatus for modulating the facsimile signals received along the transmission network.

Abstract: A digital circuit multiplication system for interconnecting a transmission trunk link having a plurality of bearer channels to a second plurality of telephone communication trunks, with the second plurality exceeding the first. The system comprises transmission apparatus at a first end of the transmission link within which there is apparatus for detecting signals on the second plurality of telephone communication trunks and apparatus for assigning each trunk on which signals are present to an available one of the first plurality of bearer channels and for providing assignment messages indicating such assignments. The speech signals are transmitted in bit reduced form by adaptive differential pulse code modulation (ADPCM) transmitting apparatus which is operative to be coupled to the first plurality of bearer channels.

Abstract: A TASI system for interconnecting a transmission trunk having a first plurality of communication channels with a defined signal transmission frequency band to a second plurality of telephone communication lines, the second plurality exceeding the first end of the transmission trunk including apparatus for detecting signals on the second plurality and apparatus for assigning each telephone communication line on which signals are present to an available one of the first plurality of communication channels; receiving apparatus at a second end of the transmission link including apparatus for assigning each of the first plurality carrying signals to a corresponding one of the second plurality in accordance with assignment information received from the transmission apparatus; and apparatus for communicating messages including assignment information between the transmission apparatus and the receiving apparatus in said signal transmission band in serial data form along said first plurality of communication channels.

Abstract: A telecommunication system for interconnecting a plurality of telephone communication trunks to a transmission network, the system including transmission apparatus at a first end of the transmission network including apparatus for detecting facsimile signals on the plurality of telephone communication trunks, apparatus for demodulating the facsimile signals, apparatus for transmitting along the transmission network, in demodulated form, the facsimile signal output from the apparatus for demodulating, and receiving apparatus at a second end of the transmission network including apparatus for modulating the facsimile signals received along the transmission network.