Comb-based wavelength division multiplexing
AssigneeNokia Solutions and Networks Oy
InventorDi Che
Life of this patent
Estimating the term…
Abstract
An optical transmitter capable of colorless WDM includes a source of optical frequency comb (OFC) light having a plurality of separate optical frequency tones, and a plurality of optical modulators connected in parallel to modulate different parts of the OFC light with corresponding modulating signals, each of the parts including the plurality of separate optical frequency tones. An optical combiner combines the different parts of the OFC light to obtain an output optical signal of the optical transmitter. MIMO processing may be used to recover the modulating signals at an optical receiver using, or to configure the modulating signals at the transmitter so that each of the frequency tones is modulated with a corresponding target data signal.
Claims20
An apparatus comprising:
- an optical transmitter comprising:
- an optical frequency comb (OFC) source to provide OFC light comprising a plurality of separate optical frequency tones;
- an optical splitter to split the OFC light to propagate along at least three different paths, each of the paths comprising an optical modulator to modulate received light with a respective modulating signal, wherein the received light of each of the optical modulators comprises the plurality of separate optical frequency tones;
- and
- an optical combiner to combine light received from the at least three different paths to obtain an output optical signal of the optical transmitter,
- wherein the at least three paths have different optical path lengths to impose different delays to light propagating along different ones of the paths.
A method for optically transmitting a plurality of data signals, the method comprising:
- splitting light comprising a comb of separate optical frequency tones to propagate along at least three optical paths, the at least three optical paths having different optical path lengths to impose different delays upon the light propagating along the different paths;
- modulating parts of the light propagating along the at least three optical paths with respective modulating signals, each of the parts comprising the comb of separate optical frequency tones;
- and
- combining the at least three different parts of the light to obtain an output optical signal, wherein the different ones of the parts are combined in the output optical signal with the different delays.
A system comprising:
- an optical transmitter comprising:
- an optical frequency comb (OFC) source to provide OFC light comprising a plurality of separate optical frequency tones;
- a plurality of optical modulators connected to modulate different parts of the OFC light with respective modulating signals, each of the parts comprising the plurality of separate optical frequency tones;
- and
- an optical combiner to combine the different parts of the OFC light with different respective delays to obtain an output optical signal;
- and
- an optical receiver comprising:
- a plurality of optical-to-electrical (OE) converters to detect modulation of respective ones of the optical frequency tones in an optical signal received from the optical transmitter, and to output a plurality of detected modulation signals;
- and
- a digital signal processor configured to perform multi-input multi-output (MIMO) processing on the plurality of detected modulation signals to separately estimate the modulating signals of the optical transmitter.
Dependencies are inferred from the claim text.