Ultra-wide band AWG multiplexer
View Patent ↗A multiplexing AWG device capable of producing an ultra-wideband, low ripple, flat-top signal is presented. The AWG device includes an AWG unit and a two-section waveguide coupled to the AWG unit. The two-section waveguide has a first section and a second section. The first section produces a signal having a double-peak field profile and has a first input end and a first output end. The second section reduces the phase variation of the signal having the double-peak field profile exiting the first section. The second section has a second input end that is coupled to the first output end. For example, the first section may be a parabolic tapered waveguide and the second section may be a rectangular waveguide.
1. A method of producing a multiplexed ultra-wide flat-top passband shaped signal, the method comprising:
passing an input signal through an AWG unit;
converting the input signal to a signal with a double-peak field profile; and
generating the multiplexed ultra-wide flat-top passband shaped signal by reducing a phase variation of the signal with the double-peak field profile, wherein the ultra-wide flat-top passband shaped signal has a 0.5-dB width of greater than or equal to 80% of the channel spacing regardless of channel spacing.
2. The method of claim 1 , wherein producing the signal with the double-peak field profile comprises passing an input signal through a tapered waveguide for non-adiabatic expansion.
3. The method of claim 2 further comprising selecting the tapered waveguide to produce widest passband shape without the dip between the peaks of the double-peak signal exceeding a preselected depth.
4. The method of claim 3 , wherein the preselected depth is about 3 dB.
5. The method of claim 2 , wherein the tapered waveguide is a parabolic tapered waveguide.
6. The method of claim 1 , wherein producing the signal with the double-peak field profile comprises using a waveguide splitter.
7. The method of claim 1 , wherein the converting of the input signal to the signal with a double-peak field profile is done before passing the input signal through the AWG unit.
8. The method of claim 1 , wherein the converting of the input signal to the signal with a double-peak field profile is done after passing the input signal through the AWG unit.
9. The method of claim 1 , wherein the ultra-wide flat-top passband shaped signal has a 0.5-dB passband width of about 0.4 nm in a 50 GHz channel spaced system where channels are 0.4 nm apart.
10. The method of claim 1 , wherein the ultra-wide flat-top passband shaped signal has a 1.0-dB passband width of about 0.5 nm in a 50 GHz channel spaced system where channels are 0.4 nm apart.
11. The method of claim 1 , wherein the ultra-wide flat-top passband shaped signal has a 3.0-dB passband width of about 0.6 nm in a 50 GHz channel spaced system where channels are 0.4 nm apart.
12. The method of claim 1 , wherein the ultra-wide flat-top passband shaped signal has a 1.0-dB width of greater than or equal to 100% of the channel spacing regardless of the size of channel spacing.
13. The method of claim 1 , wherein the ultra-wide flat-top passband shaped signal has a 3.0-dB passband width of greater than or equal to 120% of the channel spacing regardless of size of channel spacing.
14. The method of claim 1 , wherein the ultra-wide flat-top passband shaped signal has a 0.5-dB width of greater than 120% of the channel spacings regardless of the size of channel spacing.
15. The method of claim 1 , wherein the ultra-wide flat-top passband shaped signal has a 1.0-dB width of greater than 150% regardless of size of channel spacing.
16. The method of claim 1 , wherein the ultra-wide flat-top passband shaped signal has a 3.0-dB passband width of greater than or equal to 200% regardless of size of channel spacing.
17. The method of claim 1 , wherein reducing the phase variation comprises passing the signal with the double-peak field profile through a straight waveguide having a length of about 300 μm.
18. A method of producing an ultra-wide flat-top passband shaped signal, the method comprising:
passing a plurality of input signals through an AWG unit;
separately converting each of the input signals to a double-peak signal; and
separately changing a phase variation of each double-peak signal to generate the ultra-wide flat-top passband shaped signal, wherein the ultra-wide flat-top passband shaped signal has a 0.5-dB width of greater than or equal to 80% of the channel spacing regardless of channel spacing.