Optical cross-connect apparatus

1. An optical cross-connect apparatus for performing non-blocking optical cross-connection of n WDM input optical signals each containing m different wavelengths λ1 through λm, the apparatus comprising:

n first wavelength converters for converting the m different wavelengths λ1 through λm contained in the WDM input optical signals into 2m wavelengths λ1 through λ2m;

a first wavelength cross-connector for performing cross-connection according to wavelengths, the cross-connector including:

n first demultiplexers for separating the optical signals wavelength-converted by the first wavelength converters into 2m wavelengths, and

n first multiplexers for combining optical signals with the 2m separated wavelengths,

wherein same wavelengths should not be sent via each of bundles of 2m/n lines by which the first demultiplexers and the first multiplexers are connected;

n second wavelength converters for converting the 2m wavelengths contained in the optical signals cross-connected by the first wavelength cross-connector into 2m wavelengths;

a second wavelength cross-connector for performing cross-connection according to wavelengths, the cross-connector including:

n second demultiplexers for separating the optical signals wavelength-converted by the second wavelength converters into 2m wavelengths, and

n second multiplexers for combining optical signals with the 2m separated wavelengths,

wherein same wavelengths should not be sent via each of bundles of 2m/n lines by which the second demultiplexers and the second multiplexers are connected; and

n third wavelength converters for converting the 2m wavelengths λ1 through λ2m contained in the optical signals cross-connected by the second wavelength cross-connector into m wavelengths λ1 through λm and for sending the m wavelengths λ1 through λm.

2. An optical cross-connect apparatus for performing non-blocking optical cross-connection of n WDM input optical signals each containing m different wavelengths λ1 through λm, the apparatus comprising:

n first wavelength converters for converting the m different wavelengths λ1 through λm contained in the WDM input optical signals into 2m wavelengths λ1 through λ2m;

a first wavelength cross-connector for performing cross-connection according to wavelengths, the cross-connector including:

n first demultiplexers for separating the optical signals wavelength-converted by the first wavelength converters into 2m wavelengths, and

2n first multiplexers for combining optical signals with m separated wavelengths,

wherein same wavelengths should not be sent via each of bundles of m/n lines by which the first demultiplexers and the first multiplexers are connected;

2n second wavelength converters for converting the m wavelengths contained in the optical signals cross-connected by the first wavelength cross-connector into m wavelengths;

a second wavelength cross-connector for performing cross-connection according to wavelengths, the cross-connector including:

2n second demultiplexers for separating the optical signals wavelength-converted by the second wavelength converters into m wavelengths, and

n second multiplexers for combining optical signals with the 2m separated wavelengths,

wherein same wavelengths should not be sent via each of bundles of m/n lines by which the second demultiplexers and the second multiplexers are connected; and

n third wavelength converters for converting the 2m wavelengths λ1 through λ2m contained in the optical signals cross-connected by the second wavelength cross-connector into m wavelengths λ1 through λm and for sending the m wavelengths λ1 through λm.

3. An optical cross-connect apparatus for performing non-blocking optical cross-connection of n WDM input optical signals each containing m different wavelengths λ1 through λm, the apparatus comprising:

n first wavelength converters for converting the m different wavelengths λ1 through λm contained in the WDM input optical signals into (2m−1) wavelengths λ1 through λ2m−1;

a first wavelength cross-connector for performing cross-connection according to wavelengths, the cross-connector including:

n first demultiplexers for separating the optical signals wavelength-converted by the first wavelength converters into (2m−1) wavelengths, and

(2m−1) first multiplexers for combining optical signals with n separated wavelengths,

wherein each of the first demultiplexers is connected to each of the first multiplexers by one line;

(2m−1) second wavelength converters for converting the n wavelengths contained in the optical signals cross-connected by the first wavelength cross-connector into n wavelengths;

a second wavelength cross-connector for performing cross-connection according to wavelengths, the cross-connector including:

(2m−1) second demultiplexers for separating the optical signals wavelength-converted by the second wavelength converters into n wavelengths, and

n second multiplexers for combining optical signals with (2m−1) separated wavelengths,

wherein each of the second demultiplexers is connected to each of the second multiplexers by one line; and

n third wavelength converters for converting the (2m−1) wavelengths λ1 through λ2m−1contained in the optical signals cross-connected by the second wavelength cross-connector into m wavelengths λ1 through λm and for sending the m wavelengths λ1 through λm.

4. An optical cross-connect apparatus for performing non-blocking optical cross-connection of n WDM input optical signals each containing m different wavelengths λ1 through λm, the apparatus comprising:

n input-side wavelength converters for converting the m different wavelengths λ1 through λm contained in the WDM input optical signals into mn wavelengths λ1 through λmn;

a wavelength cross-connector for performing cross-connection according to wavelengths, the cross-connector including:

n demultiplexers for separating the optical signals wavelength-converted by the input-side wavelength converters into mn wavelengths, and

n multiplexers for combining optical signals with the mn separated wavelengths,

wherein same wavelengths should not be sent via each of bundles of m lines by which the demultiplexers and the multiplexers are connected; and

n output-side wavelength converters for converting the mn wavelengths λ1 through λmn contained in the optical signals cross-connected by the wavelength cross-connector into m wavelengths λ1 through λm and for sending the m wavelengths λ1 through λm.

5. An optical cross-connect apparatus for performing optical cross-connection of n WDM input optical signals each containing m different wavelengths λ1 through λm, the apparatus comprising:

n input-side wavelength converters for converting the m different wavelengths λ1 through λm contained in the WDM input optical signals into m wavelengths;

a wavelength cross-connector for performing cross-connection according to wavelengths, the cross-connector including:

n demultiplexers for separating the optical signals wavelength-converted by the input-side wavelength converters into m wavelengths, and

n multiplexers for combining optical signals with the m separated wavelengths; and

n output-side wavelength converters for converting the m wavelengths contained in the optical signals cross-connected by the wavelength cross-connector into m wavelengths λ1 through λm and for sending the m wavelengths λ1 through λm.