Patent ID: 6718140
Filing Date: 2004-04-06
Classification: H04J,H04Q

Abstract:
An optical wavelength division multiplexing transmission network device; comprising N transmitting and receiving apparatuses; and an NÃ—N wavelength multi/demultiplexer having a first I/O part group composed of N ports, each of which is connected to each different one of said N transmitting and receiving apparatuses and a second I/O port group composed of N ports, each of which is connected to each different one of said N transmitting and receiving apparatuses,wherein each of N optical signals, which has a different wavelength from the others, is transmitted at each of N paths between any one of the ports of the first I/O port group and N ports of the second I/O port group, each of N optical signals, which has a different wavelength from the others, is transmitted at each of N paths between any one of the ports of the second I/O port group and N ports of the first I/O port group, N port combinations for transmitting optical signals having an equal wavelength exists for each wavelength among NÃ—N port combinations made by the N ports of the first I/O port group and the N ports of the second I/O port group, among the N port combinations for transmitting the optical signals having the equal wavelength, in M port combinations the optical signals are transmitted from the first I/O port group to the second I/O port group, and in Nâˆ’M port combinations the optical signals are transmitted from the second I/O port group to the first I/O port group, and the port of the second I/O port group to which the optical signal is transmitted from the port of the first I/O port group connected to the any one of the transmitting and receiving apparatuses and the port of the first I/O port group to which the optical signal is transmitted from the port of the second I/O port group connected to the any one of the transmitting and receiving apparatuses are connected to the different transmitting and receiving apparatus.