Color free WDM PON based on broadband optical transmitters
View Patent ↗A Wavelength Division Multiplexed Passive Optical Network (WDM-PON) includes a plurality of broadband light sources, each broadband light source being connected to receive a respective data signal and generating a corresponding modulated broadband optical signal. An Array Waveguide Grating (AWG) is connected for receiving each modulated broadband optical signal through a respective branch port and for generating a filtered broadband signal. The AWG implements a filter function comprising a respective pass-band associated with each branch port such that the filtered broadband signal exhibits a respective intensity peak associated with each pass-band. Each intensity peak is modulated with data from a respective one of the broadband light sources. A bandwidth of the respective modulated broadband optical signal generated by each broadband light source is at least equal to the width of a channel-band of the AWG.
1. A Wavelength Division Multiplexed Passive Optical Network (WDM-PON) comprising:
a plurality of broadband light sources each for a respective channel of the WDM-PON, each broadband light source being connected to receive a respective data signal and to generate a corresponding modulated broadband optical signal; and
an Array Waveguide Grating (AWG) for receiving each modulated broadband optical signal through a respective one of a plurality of branch ports and for providing a filtered broadband signal based on the received modulated broadband optical signals, the AWG having a filter function that includes a plurality of pass-bands with each respective pass-band associated with a separate one of the plurality of branch ports such that the filtered broadband signal exhibits a respective intensity peak associated with each of the plurality of pass-bands, and wherein each respective pass-band separately includes a center wavelength and a filter channel bandwidth to form the respective intensity peak at each channel wavelength, and the AWG provides the filtered broadband signal having a plurality of intensity peaks modulated with data from the plurality of broadband light sources;
wherein a width of a bandwidth of the respective modulated broadband optical signal generated by each of the plurality of broadband light sources is equal to or greater than a width of a channel-band of the WDM-PON.
2. The network as claimed in claim 1 , wherein the AWG selects the filter channel bandwidth of each pass-band based on a Relative Intensity Noise (RIN) of the corresponding pass-band and inter-channel cross-talk within the filtered broadband signal.
3. The network as claimed in claim 1 , wherein a spacing between adjacent channel pass-bands of the AWG filter function follows a predetermined spectral grid.
4. The network as claimed in claim 3 , wherein the predetermined spectral grid is wider than a set of channels for conveying downlink signals of the WDM PON.
5. The network as claimed in claim 3 , wherein the predetermined spectral grid is wider than a set of channels for conveying uplink signals of the WDM PON.
6. The network as claimed in claim 1 , further comprising an optical amplifier for amplifying the filtered broadband signal provided by the AWG.
7. The network as claimed in claim 1 , wherein the respective data signal supplied to each broadband light source is Forward Error Correction (FEC) encoded.
8. In a Wavelength Division Multiplexed Passive Optical Network (WDM-PON), a method of generating optical channel signals, the method comprising:
each one of a plurality of broadband light sources receiving a respective data signal and generating a corresponding modulated broadband optical signal having a width of a bandwidth that is equal to or greater than a width of a channel-band of the WDM-PON each of the plurality of light sources separately corresponding to a respective channel of the WDM-PON; and
an Array Waveguide Grating (AWG) receiving each modulated broadband optical signal through a respective one of a plurality of branch ports and providing a filtered broadband signal based on the received modulated broadband optical signals;
wherein the AWG has a filter function that includes a plurality of pass-bands with each respective pass-band associated with a separate one of the plurality of branch ports such that the filtered broadband signal exhibits a respective intensity peak associated with each of the plurality of pass-bands, and wherein each respective pass-band separately includes a center wavelength and a filter channel bandwidth to form the respective intensity peak, and the AWG provides the filtered broadband signal having a plurality of intensity peaks modulated with data from the plurality of broadband light sources.
9. The method as claimed in claim 8 , wherein the AWG selects the filter channel bandwidth of each pass-band based on a Relative Intensity Noise (RIN) of the corresponding pass-band and inter-channel cross-talk within the filtered broadband signal.
10. The method as claimed in claim 8 , wherein a spacing between adjacent channel pass-bands of the AWG filter function follows a predetermined spectral grid.
11. The method as claimed in claim 10 , wherein the predetermined spectral grid is wider than a set of channels for conveying downlink signals of the WDM PON.
12. The method as claimed in claim 10 , wherein the predetermined spectral grid is wider than a set of channels for conveying uplink signals of the WDM PON.
13. The method as claimed in claim 8 , further comprising amplifying the filtered broadband signal provided by the AWG by using an optical amplifier.
14. The method as claimed in claim 8 , wherein the respective data signal supplied to each broadband light source is Forward Error Correction (FEC) encoded.