Optical switching device having recirculating structure and optical switching method therefor

DETAILED DESCRIPTION An object of the present invention is to provide an optical switching network having a recirculating structure and an optical switching method therefor, for use in broadband service.
Another object of the present invention is to provide a single-stage optical switching network and an optical switching method therefor, for shuffling input cells through log.
sub.
2 N circulations and switching the input cells according to corresponding address bits during the circulations.
To achieve the above objects, there is provided an optical switching network having N input couplers each having a cell input port and a recursive input port, N output couplers each having a cell output port and a recursive output port, N/2 switch couplers connected between the input couplers and the output couplers, and a controller having a routing table, for generating control signals for the respective input, output, and switch couplers upon input of cells.
The optical switching network has a single-stage optical recursive loop in which an x-numbered recursive output port is connected to a 2x-numbered recursive input port if 0.
ltoreq.
x<N/2, and the x-numbered recursive output port is connected to a (2x-N+1)-numbered recursive input port if N/2.
ltoreq.
x<N.
The N input couplers receive the cells via the cell input ports upon input of the cells, the N/2 switch couplers recursively switch the cells log.
sub.
2 N-times by connecting the recursive output ports to the corresponding recursive input ports during circulations, and the N output couplers output the cells via the cell output ports at the termination of switching.