Variation-tolerant wavelength division multiplexing receiver and transceiver, and associated methods

1. A variation-tolerant receiver comprising:

a plurality of receiver resonators for demultiplexing a multiplexed modulated signal received from at least one wavelength division multiplexing (WDM) transmitter having a plurality of transmitter resonators, each of the receiver resonators having a receiver resonance linewidth not exceeding a minimum spacing between two adjacent transmitter resonances of the transmitter resonators; and

the receiver resonances collectively spanning a free spectral range of one of the receiver resonators such that the variation-tolerant receiver achieves gapless spectral response.

2. The variation-tolerant receiver of claim 1 , a center-to-center wavelength difference between any two adjacent receiver resonances being between 0.5 times and 1.5 times a linewidth of either one of said adjacent receiver resonances, such that any two adjacent receiver resonances overlap each other.

3. The variation-tolerant receiver of claim 1 , a linewidth of each receiver resonator being equal and number of receiver resonators equaling or exceeding quotient of (a) a receiver resonator free-spectral range (FSR) and (b) the linewidth.

4. The variation-tolerant receiver of claim 1 , the number of receiver resonators being at least twice number of transmitter resonators.

5. The variation-tolerant receiver of claim 1 , a smallest FSR of any of the receiver resonators exceeding a maximum FSR of any of the transmitter resonators.

6. The variation-tolerant receiver of claim 1 , number of receiver resonances being centered within a full-width at half maximum of a transmitter resonance, and equaling or exceeding total number of transmitter resonators when operating at any temperature between 25° C. and 50° C.

7. The variation-tolerant receiver of claim 1 , linewidth of each receiver resonator equaling linewidth of each transmitter resonator.

8. The variation-tolerant receiver of claim 7 , number of receiver resonators being greater than or equal to finesse of a transmitter resonator.

9. The variation-tolerant receiver of claim 1 , each adjacent pair of transmitter resonances being separated in wavelength Δλ and having respective spectral widths δλ 1 and δλ 2 , Δλ exceeding 1/2(δλ 1 +δλ 2 ).

10. The variation-tolerant receiver of claim 9 , a guard band between each adjacent pair of transmitter resonances having a spectral width equal to Δλ−1/2(δλ 1 +δλ 2 ), that exceeds characteristic spectral shift of transmitter resonance resulting from process variation.

11. The variation-tolerant receiver of claim 1 , each receiver resonator being a silicon-on-insulator device.

12. The variation-tolerant receiver of claim 1 , further comprising a proximally-located variation-tolerant WDM transceiver having a plurality of proximal transmitter resonators, each resonators having a transmitter resonance; and receiver resonance linewidth not exceeding a minimum spacing between two adjacent transmitter resonances of the proximal transmitter resonators.

13. The variation-tolerant WDM transceiver of claim 12 , wherein

a proximal transmitter resonator comprises one of a microring resonator and a racetrack resonator and/or wherein a receiver resonator comprises one of a microring resonator and a racetrack resonator.

14. The variation-tolerant WDM transceiver of claim 12 , further comprising a broadband light source optically coupled to the plurality of proximal transmitter resonators and having a bandwidth exceeding an FSR of each proximal transmitter resonator.

15. A variation-tolerant receiver comprising a plurality of receiver resonators configured to demultiplex a multiplexed modulated signal received from a remotely-located wavelength division multiplexing (WDM) transmitter having a plurality of transmitter resonators,

each receiver resonator having perimeter, shape, cross-sectional dimensions, and bulk refractive index that determine a plurality of receiver resonances each having a receiver resonance linewidth in response to electromagnetic radiation propagating therethrough;

each receiver resonance linewidth not exceeding a minimum spacing between two adjacent transmitter resonances of the transmitter resonators; and

all receiver resonances collectively spanning a free spectral range of one of the receiver resonators such that the variation-tolerant receiver achieves gapless spectral response.

16. The variation-tolerant receiver of claim 15 , further comprising a proximally-located WDM transmitter having a plurality of proximal transmitter resonators, each receiver resonance linewidth not exceeding a minimum spacing between two adjacent transmitter resonances of the proximal transmitter resonators.

17. A method for passively compensating transmitter-receiver channel mismatch in a transceiver, comprising:

modulating a plurality of narrowband transmitter carriers to form a plurality of modulated signals;

multiplexing each of the modulated signals to form a multiplexed modulated signal; and

demultiplexing the multiplexed modulated signal to form a plurality of receiver signals, each receiver signal having a spectral width not exceeding a minimum spectral spacing between two adjacent transmitter carriers.

18. A method for variation-tolerant signal reconstruction, comprising:

receiving a multiplexed modulated signal, having a first center carrier wavelength, on one or more receiver channels of a plurality of receiver channels each having one of a respective plurality of center carrier wavelengths, the receiver channels that receive the modulated signal having a receiver center carrier wavelength closer to the first carrier wavelength than any other receiver center carrier wavelength.

19. The method of claim 18 , the modulated signal having an associated transmitter channel that is one of a first plurality of transmitter channels, each having one of a respective plurality of center carrier wavelengths.

20. The method of claim 18 , the number of receiver channels being at least twice the number of transmitter channels.