| 摘要 |
An improved network system (10) for communicating digital data between multiple devices (12) physically dispersed throughout a facility. The network system is comprised of a transmission medium (20) formed into first and second buses which are physically routed together, preferably as a single cable, through a facility containing the devices to be interconnected by the network. Each such device is coupled to the network by connecting it to both the first and second buses (24, 26) and digital data is transmitted unidirectionally along each bus in opposite directions. Each device (12) when transmitting, concurrently propagates digitally encoded signals in opposite directions along both buses. Each device (12) receives such encoded signals on either bus, dependent on its location relative to the transmitting device. Each device (12) is coupled to the buses by a network control subsystem, i.e., controller (14), which includes amplifier means (54, 56, 60; 62) which enables the operational length of the network to be extended in increments. Each controller (14) preferably also includes repeater means (58) to enhance noise immunity by reshaping and resynchronizing the signal transmitted along the network. |
