| 摘要 |
<p>A communications system comprises a line terminal (1), a plurality of customer terminals (2), and a passive optical network for supporting traffic between the line terminal and the customer terminals. The line terminal (1) has a terminal unit means (BTS(n)) for relatively narrow bandwidth traffic, and a second terminal unit means (BTS(1) to BTS(n-1)) for relatively wider bandwidth traffic. A time domain multiplexer (14) is arranged to multiplex the traffic from the first and second terminal unit means for downstream transmission over the network (18). Each customer terminal (2) has a first service unit means for relatively narrow bandwidth traffic and a second service unit means for relatively wider bandwidth traffic. Each customer terminal (2) has a demultiplexer (22) arranged to receive multiplexed downstream traffic from the network (18), and to segregate the traffic between the first and second service unit means. Each customer terminal (2) has control means for generating relatively narrow bandwidth control signals for upstream transmission over the network, the second terminal unit means (BTS(1) to BTS(n-1)) of the line terminal (1) being responsive to the control signals from a given customer terminal (2) to control the transmission of the relatively wider bandwidth traffic to that customer terminal. The downstream transmission is by TDM and the upstream transmission is by TDMA.</p> |
