Patent ID: 6078950
Filing Date: 2000-06-20
Classification: H04H,H04N

Abstract:
A transmission system wherein a broadband distribution network (2) has a center (1) and a plurality of subscriber terminals (26) connected thereto, the subscriber terminals (26) being capable of receiving television, sound, and data signals to be distributed, and subscriber-assigned signals from the center (1), and of transmitting upstream signals to the center (1), and wherein the broadband distribution network (2) comprises a plurality of amplifiers (10) each of which has a group of subscriber terminals (26) connected thereto by an access network section (11), characterized in that at least one of the amplifiers (10) or at least one of the access network sections (11) has a back-channel facility (4) connected thereto which is also connected to a separate two-wire line (21) coupled directly or indirectly to the center (1), that the back-channel facility (4) receives the upstream signals from the subscriber terminals (26) of said group of subscriber terminals, and the back-channel facility (4) transmits the received upstream signals to the center (1) according to a protocol which governs multiple access by the subscriber terminals (26) to the two-wire line (21), said protocol determining if each upstream signal from any subscriber terminal (26) in said group of subscriber terminals is received without collision with any other subscriber signal, and if so the subscriber signal is communicated to the center (1) by the back-channel facility (4), and otherwise the back-channel facility (4) requests that each subscriber terminal (26) from which an upstream signal was received with collision, retransmit said upstream signal; and further characterized in that the back-channel facility (4) comprises a regenerator (9), a receiving device (12) connected to the regenerator (9) for receiving the upstream signals, a transmitting device (13) connected to the regenerator (9) for transmitting acknowledgement and downstream signals to the subscriber terminals (26), which acknowledgement and downstream signals can enter the back-channel facility (4) at a port (7) connectable to the two-wire line (21), and a modulator-demodulator (27) connected to the regenerator (9) and the two-wire line (21), and that the regenerator (9) comprises means (28, 29, 30, 31) for processing the upstream signals according to the multiple-access protocol, so that the upstream signals are transmitted to the center (1) collision-free.