Japan Science and Technology Agency

Nagoya University

Tokai National Higher Education and Research System

Yojiro Mori

Hiroshi Hasegawa

Ken-ichi Sato

Kosuke Sato

Yuki Terada

Koh Ueda

In the case of a OXC device having a route & select-type configuration of the conventional technique, when the port number is 20, then the entire device requires 120 WSSs having a 1&#xd7;9 configuration. In the case of a route & select-type OXC device having ports more than 20 ports, a large amount of expensive WSSs is required. Thus, such a device is impractical from the viewpoint of cost. Thus, the expansion depending on an increase of traffic at nodes was impossible, flexible scalability could not be provided, and a reasonable network operation from the viewpoint of economy was difficult. According to the OXC device of this disclosure, regardless of the input port number and the output port number of the device, WSSs having a smaller scale than the conventional technique are used and the WSSs are internally-connected from a viewpoint different from that of the conventional technique, thus providing the device having a significantly-reduced cost.

Optical cross-connect device

A wavelength routing SW is a large-scale optical switch device of a conventional technique, and it requires as many wavelength-tunable light sources as the number of input ports. For the wavelength-tunable light sources to achieve a stable oscillating operation across a wide wavelength range, a complicated control mechanism is necessary. This has been an obstacle in providing a large-scale optical switch device in terms of cost and circuit scale. A wavelength routing SW in the present disclosure includes N wavelength group generators, a splitting-selection unit, and MN tunable filters. Each wavelength group generator includes M fixed-wavelength light sources. Inexpensive general-purpose devices that require no control mechanism for wavelength tuning can be used as the fixed-wavelength light source. The channel loss in the optical switch device can also be reduced by using light sources with a limited narrow range of tunable wavelengths and the wavelength-dependent output port selecting function of an AWG.

Optical switch device

An optical network transmits a wavelength division multiplexing optical signal from a transmission to a reception node via a reconfigurable optical add/drop multiplexer and/or path cross-connect apparatuses. When optical or optical super channels made of successive optical subcarriers input from input optical fibers are routed or switched to an output optical fiber in the multiplexer and/or apparatus passed through by a wavelength division multiplexing optical signal transmitted from the predetermined transmission node to the predetermined reception node, the adjacent channels output to the same output fiber in each input fiber is collectively demultiplexed without being demultiplexed for the channels and is routed or switched to the output fiber. Channel routing paths and frequency arrangements are controlled such that the number of filtering times by a wavelength division filtering mechanism on one or both sides on the frequency axis of the channel becomes equal to or less than a predetermined value.

Optical network

Growing community of inventors

Nagoya, Japan

Yojiro Mori