| 摘要 |
PURPOSE:To increase the number of connection available nodes by constituting a branch coupling rate between a node and an optical bus so as to be controlled externally. CONSTITUTION:Branch coupling rate variable branching couplers 1a-1c whose branch coupling rate is controlled externally through the application of a control voltage are used and nodes 2a, 2e, 16b-16d provided with two modes, i.e., transmission mode and reception mode are used. Then branch coupling rate control means 17b-17d are used to control so that the branching coupling rate between the bus and the node in the transmission mode is larger than the branch coupling rate between the bus and the node in the reception mode. Thus, the transmission loss of the optical bus is reduced and the number of connection available nodes is increased. |
