Transmission of optical signals of different modulation formats in discrete bands
A method and apparatus for transmitting optical signals of different modulation formats in distinct bands. The optical signals within each band may be separated by a predetermined channel spacing, and the distinct bands may be separated by a predetermined band separation distance. The band separation distance may be about twice the predetermined channel spacing.
1 . An apparatus for transmitting an optical signal comprising:
at least one first modulation format transmitter, each of said first modulation format transmitters being configured to provide an optical signal at a different associated wavelength and having data modulated thereon according to a first modulation format; and
at least one second modulation format transmitter, each of said second modulation format transmitters being configured to provide an optical signal at a different associated wavelength and having data modulated thereon according to a second modulation format different from said first modulation format;
each of said signals having said first modulation format being grouped in a first wavelength band and each of said signals having said second modulation format being grouped in a second wavelength band, said first and second wavelength bands being separated by a predetermined band separation.
2 . An apparatus according to claim 1 , wherein each of said signals in said first wavelength band and each of said signals in said second wavelength band are separated by a predetermined channel spacing.
3 . An apparatus according to claim 2 , wherein said predetermined channel spacing is 25 GHz.
4 . An apparatus according to claim 2 , wherein said predetermined channel spacing is 33 GHz.
5 . An apparatus according to claim 2 , wherein said predetermined band separation is greater than said predetermined channel spacing.
6 . An apparatus according to claim 2 , wherein said predetermined band separation is about two times said predetermined channel spacing.
7 . An apparatus according to claim 1 , wherein said predetermined band separation is 50 GHz.
8 . An apparatus according to claim 1 , wherein said predetermined band separation is 66 GHz.
9 . An apparatus according to claim 1 , wherein said first modulation format is an OOK format.
10 . An apparatus according to claim 1 , wherein said second modulation format is a DPSK format.
11 . An apparatus according to claim 1 , wherein said first modulation format is an OOK format and said second modulation format is a DPSK format.
12 . An apparatus according to claim 1 , said apparatus comprising a plurality of said second modulation format transmitters.
13 . An apparatus for transmitting an optical signal comprising:
a plurality of first modulation format transmitters, each of said first modulation format transmitters being configured to provide an optical signal at a different associated wavelength and having data modulated thereon according to an OOK modulation format; and
a plurality of second modulation format transmitters, each of said second modulation format transmitters being configured to provide an optical signal at a different associated wavelength and having data modulated thereon according to a DPSK modulation format;
each of said signals having said OOK modulation format being grouped in a first wavelength band and each of said signals having said DPSK modulation format being grouped in a second wavelength band, said signals in said first and second wavelength bands being separated by a predetermined channel spacing, and said first and second wavelength bands being separated by a predetermined band separation greater than said predetermined channel spacing.
14 . An apparatus according to claim 13 , wherein said predetermined channel spacing is 25 GHz.
15 . An apparatus according to claim 13 , wherein said predetermined channel spacing is 33 GHz.
16 . An apparatus according to claim 13 , wherein said predetermined band separation is about two times said predetermined channel spacing.
17 . An apparatus according to claim 13 , wherein said predetermined band separation is 50 GHz.
18 . An apparatus according to claim 13 , wherein said predetermined band separation is 66 GHz.
19 . A method of transmitting a WDM optical signal comprising:
transmitting a first plurality of wavelengths having data modulated thereon according to a first modulation format in a first wavelength band; and
transmitting a second plurality of optical signals having a second modulation format different from said first modulation format in a second wavelength band separated from said first wavelength band by a predetermined band separation.
20 . A method according to claim 19 , wherein each of said signals in said first wavelength band and each of said signals in said second wavelength band are separated by a predetermined channel spacing.
21 . A method according to claim 20 , wherein said predetermined channel spacing is 25 GHz.
22 . A method according to claim 20 , wherein said predetermined channel spacing is 33 GHz.
23 . A method according to claim 20 , wherein said predetermined band separation is greater than said predetermined channel spacing.
24 . A method according to claim 20 , wherein said predetermined band separation is about two times said predetermined channel spacing.
25 . A method according to claim 19 , wherein said predetermined band separation is 50 GHz.
26 . A method according to claim 19 , wherein said predetermined band separation is 66 GHz.
27 . A method according to claim 19 , wherein said first modulation format is an OOK format.
28 . A method according to claim 19 , wherein said second modulation format is a DPSK format.
29 . A method according to claim 19 , wherein said first modulation format is an OOK format and said second modulation format is a DPSK format.