Abstract

Arrayed waveguide gratings (AWG) are widely used as wavelength division multiplexers (MUX) and demultiplexers (DEMUX) in optical networks. Here we propose and demonstrate that conventional AWGs can also be used as integrated spectral filters to realize a Fast Fourier transform (FFT) and its inverse form (IFFT). More specifically, we point out that the wavelength selection conditions of AWGs when used as wavelength MUX/DEMUX also enable them to perform FFT/IFFT functions. Therefore, previous research on AWGs can now be applied to optical FFT/IFFT circuit design. Compared with other FFT/IFFT optical circuits, AWGs have less structural complexity, especially for a large number of inputs and outputs. As an important application, AWGs can be used in optical OFDM systems. We propose an all-optical OFDM system with AWGs and demonstrate the simulation results. Overall, the AWG provides a feasible solution for all-optical OFDM systems, especially with a large number of optical subcarriers.

© 2011 OSA

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References

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    [CrossRef]
  5. Y. Benlachtar, P. M. Watts, R. Bouziane, P. Milder, D. Rangaraj, A. Cartolano, R. Koutsoyannis, J. C. Hoe, M. Püschel, M. Glick, and R. I. Killey, “Generation of optical OFDM signals using 21.4 GS/s real time digital signal processing,” Opt. Express 17(20), 17658–17668 (2009).
    [CrossRef] [PubMed]
  6. Q. Yang, S. Chen, Y. Ma, and W. Shieh, “Real-time reception of multi-gigabit coherent optical OFDM signals,” Opt. Express 17(10), 7985–7992 (2009).
    [CrossRef] [PubMed]
  7. F. Buchali, R. Dischler, A. Klekamp, M. Bernhard, and Y. Ma, “Statistical Transmission Experiments Using a Real-Time 12.1 Gb/s OFDM Transmitter”, in Conference on Optical Fiber Communication, OFC (San Diego, CA, 2010), paper OMS3 (2010).
  8. S. Chen, Y. Ma, and W. Shieh, 110-Gb/s Multi-Band Real-Time Coherent Optical OFDM Reception after 600-km Transmission over SSMF Fiber”, in Conference on Optical Fiber Communication, OFC (San Diego, CA, 2010), paper OMS2 (2010).
  9. D. Hillerkuss, T. Schellinger, R. Schmogrow, M. Winter, T. Vallaitis, R. Bonk, A. Marculescu, J. Li, M. Dreschmann, J. Meyer, S. Ben Ezra, N. Narkiss, B. Nebendahl, F. Parmigiani, P. Petropoulos, B. Resan, K. Weingarten, T. Ellermeyer, J. Lutz, M. Möller, M. Hübner, J. Becker, C. Koos, W. Freude, and J. Leuthold, “Single source optical OFDM transmitter and optical FFT receiver demonstrated at line rates of 5.4 and 10.8Tb/s,” in Conference on Optical Fiber Communication, OFC (San Diego, CA, 2010), paper PDPC1 (2010).
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    [CrossRef]
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  12. S. Chandrasekhar, X. Liu, B. Zhu, and D. W. Peckham, “Transmission of a 1.2 Tb/s 24-carrier no-guad-interval coherent OFDM superchannel over 7200-km of Ultra-Large-Area Fiber,” in Proc. ECOC 2009 (Vienna, Austria), paper PD2.6 (2009).
  13. S. Chandrasekhar and X. Liu, “Experimental investigation on the performance of closely spaced multi-carrier PDM-QPSK with digital coherent detection,” Opt. Express 17(24), 21350–21361 (2009).
    [CrossRef] [PubMed]
  14. K. Lee, C. T. D. Thai, and J.-K. K. Rhee, “All optical discrete Fourier transform processor for 100 Gbps OFDM transmission,” Opt. Express 16(6), 4023–4028 (2008).
    [CrossRef] [PubMed]
  15. K. Takiguchi, M. Oguma, H. Takahashi, and A. Mori, “PLC-based eight-channel OFDM demultiplexer and its demonstration with 160 Gbit/s signal reception,” in Conference on Optical Fiber Communication, OFC (San Diego, CA, 2010), paper OThB4 (2010).
  16. Y. Huang, D. Qian, R. E. Saperstein, P. N. Ji, N. Cvijetic, L. Xu, and T. Wang, “Dual-polarization 2x2 IFFT/FFT optical signal processing for 100-Gb/s QPSK-PDM all-optical OFDM,” in Conference on Optical Fiber Communication, OFC (San Diego, CA, 2009), paper OTuM4 (2009).
  17. D. Hillerkuss, M. Winter, M. Teschke, A. Marculescu, J. Li, G. Sigurdsson, K. Worms, S. Ben Ezra, N. Narkiss, W. Freude, and J. Leuthold, “Simple all-optical FFT scheme enabling Tbit/s real-time signal processing,” Opt. Express 18(9), 9324–9340 (2010).
    [CrossRef] [PubMed]
  18. A. J. Lowery, “Design of arrayed-waveguide grating routers for use as optical OFDM demultiplexers,” Opt. Express 18(13), 14129–14143 (2010).
    [CrossRef] [PubMed]
  19. C. R. Doerr and K. Okamoto, “Advances in silica planar lightwave circuits,” J. Lightwave Technol. 24(12), 4763–4789 (2006).
    [CrossRef]
  20. M. K. Smit and C. Van Dam, “PHASAR-based WDM-devices: Principles, design and applications,” IEEE J. Sel. Top. Quantum Electron. 2(2), 236–250 (1996).
    [CrossRef]
  21. G. Cincotti, N. Wada, and K. Kitayama, “Characterization of a full encoder/decoder in the AWG configuration for code-based photonic routers—part I: modeling and design,” J. Lightwave Technol. 24(1), 103–112 (2006).
    [CrossRef]
  22. K. Takada, M. Abe, and K. Okamoto, “Low-cross-talk polarization-insensitive 10-GHz-spaced 128-channel arrayed-waveguide grating multiplexer-demultiplexer achieved with photosensitive phase adjustment,” Opt. Lett. 26(2), 64–65 (2001).
    [CrossRef]
  23. K. Takada, M. Abe, M. Shibata, M. Ishii, and K. Okamoto, “Low-Crosstalk 10-GHz-spaced 512-channel arrayed-waveguide grating multi/demultiplexer fabricated on a 4-in wafer,” IEEE Photon. Technol. Lett. 13(11), 1182–1184 (2001).
    [CrossRef]
  24. G. Goldfarb, G. Li, and M. G. Taylor, “Orthogonal wavelength-division multiplexing using coherent detection,” IEEE Photon. Technol. Lett. 19(24), 2015–2017 (2007).
    [CrossRef]

2010

2009

2008

2007

G. Goldfarb, G. Li, and M. G. Taylor, “Orthogonal wavelength-division multiplexing using coherent detection,” IEEE Photon. Technol. Lett. 19(24), 2015–2017 (2007).
[CrossRef]

2006

2001

K. Takada, M. Abe, and K. Okamoto, “Low-cross-talk polarization-insensitive 10-GHz-spaced 128-channel arrayed-waveguide grating multiplexer-demultiplexer achieved with photosensitive phase adjustment,” Opt. Lett. 26(2), 64–65 (2001).
[CrossRef]

K. Takada, M. Abe, M. Shibata, M. Ishii, and K. Okamoto, “Low-Crosstalk 10-GHz-spaced 512-channel arrayed-waveguide grating multi/demultiplexer fabricated on a 4-in wafer,” IEEE Photon. Technol. Lett. 13(11), 1182–1184 (2001).
[CrossRef]

1996

M. K. Smit and C. Van Dam, “PHASAR-based WDM-devices: Principles, design and applications,” IEEE J. Sel. Top. Quantum Electron. 2(2), 236–250 (1996).
[CrossRef]

Abe, M.

K. Takada, M. Abe, M. Shibata, M. Ishii, and K. Okamoto, “Low-Crosstalk 10-GHz-spaced 512-channel arrayed-waveguide grating multi/demultiplexer fabricated on a 4-in wafer,” IEEE Photon. Technol. Lett. 13(11), 1182–1184 (2001).
[CrossRef]

K. Takada, M. Abe, and K. Okamoto, “Low-cross-talk polarization-insensitive 10-GHz-spaced 128-channel arrayed-waveguide grating multiplexer-demultiplexer achieved with photosensitive phase adjustment,” Opt. Lett. 26(2), 64–65 (2001).
[CrossRef]

Armstrong, J.

Ben Ezra, S.

Benlachtar, Y.

Bouziane, R.

Cartolano, A.

Chandrasekhar, S.

Chen, H.

Chen, M.

Chen, S.

Chen, W.

W. Shieh, W. Chen, and R. S. Tucker, “Polarization mode dispersion mitigation in coherent optical orthogonal frequency division multiplexed systems,” Electron. Lett. 42(17), 996–997 (2006).
[CrossRef]

Cincotti, G.

Doerr, C. R.

Freude, W.

Glick, M.

Goldfarb, G.

G. Goldfarb, G. Li, and M. G. Taylor, “Orthogonal wavelength-division multiplexing using coherent detection,” IEEE Photon. Technol. Lett. 19(24), 2015–2017 (2007).
[CrossRef]

Hillerkuss, D.

Hoe, J. C.

Ishii, M.

K. Takada, M. Abe, M. Shibata, M. Ishii, and K. Okamoto, “Low-Crosstalk 10-GHz-spaced 512-channel arrayed-waveguide grating multi/demultiplexer fabricated on a 4-in wafer,” IEEE Photon. Technol. Lett. 13(11), 1182–1184 (2001).
[CrossRef]

Killey, R. I.

Kitayama, K.

Koutsoyannis, R.

Lee, K.

Leuthold, J.

Li, G.

G. Goldfarb, G. Li, and M. G. Taylor, “Orthogonal wavelength-division multiplexing using coherent detection,” IEEE Photon. Technol. Lett. 19(24), 2015–2017 (2007).
[CrossRef]

Li, J.

Liu, X.

Lowery, A. J.

Ma, Y.

Marculescu, A.

Milder, P.

Narkiss, N.

Okamoto, K.

Püschel, M.

Rangaraj, D.

Rhee, J.-K. K.

Shibata, M.

K. Takada, M. Abe, M. Shibata, M. Ishii, and K. Okamoto, “Low-Crosstalk 10-GHz-spaced 512-channel arrayed-waveguide grating multi/demultiplexer fabricated on a 4-in wafer,” IEEE Photon. Technol. Lett. 13(11), 1182–1184 (2001).
[CrossRef]

Shieh, W.

Q. Yang, S. Chen, Y. Ma, and W. Shieh, “Real-time reception of multi-gigabit coherent optical OFDM signals,” Opt. Express 17(10), 7985–7992 (2009).
[CrossRef] [PubMed]

W. Shieh, W. Chen, and R. S. Tucker, “Polarization mode dispersion mitigation in coherent optical orthogonal frequency division multiplexed systems,” Electron. Lett. 42(17), 996–997 (2006).
[CrossRef]

Sigurdsson, G.

Smit, M. K.

M. K. Smit and C. Van Dam, “PHASAR-based WDM-devices: Principles, design and applications,” IEEE J. Sel. Top. Quantum Electron. 2(2), 236–250 (1996).
[CrossRef]

Takada, K.

K. Takada, M. Abe, M. Shibata, M. Ishii, and K. Okamoto, “Low-Crosstalk 10-GHz-spaced 512-channel arrayed-waveguide grating multi/demultiplexer fabricated on a 4-in wafer,” IEEE Photon. Technol. Lett. 13(11), 1182–1184 (2001).
[CrossRef]

K. Takada, M. Abe, and K. Okamoto, “Low-cross-talk polarization-insensitive 10-GHz-spaced 128-channel arrayed-waveguide grating multiplexer-demultiplexer achieved with photosensitive phase adjustment,” Opt. Lett. 26(2), 64–65 (2001).
[CrossRef]

Taylor, M. G.

G. Goldfarb, G. Li, and M. G. Taylor, “Orthogonal wavelength-division multiplexing using coherent detection,” IEEE Photon. Technol. Lett. 19(24), 2015–2017 (2007).
[CrossRef]

Teschke, M.

Thai, C. T. D.

Tucker, R. S.

W. Shieh, W. Chen, and R. S. Tucker, “Polarization mode dispersion mitigation in coherent optical orthogonal frequency division multiplexed systems,” Electron. Lett. 42(17), 996–997 (2006).
[CrossRef]

Van Dam, C.

M. K. Smit and C. Van Dam, “PHASAR-based WDM-devices: Principles, design and applications,” IEEE J. Sel. Top. Quantum Electron. 2(2), 236–250 (1996).
[CrossRef]

Wada, N.

Watts, P. M.

Winter, M.

Worms, K.

Xie, S.

Yang, Q.

Electron. Lett.

W. Shieh, W. Chen, and R. S. Tucker, “Polarization mode dispersion mitigation in coherent optical orthogonal frequency division multiplexed systems,” Electron. Lett. 42(17), 996–997 (2006).
[CrossRef]

IEEE J. Sel. Top. Quantum Electron.

M. K. Smit and C. Van Dam, “PHASAR-based WDM-devices: Principles, design and applications,” IEEE J. Sel. Top. Quantum Electron. 2(2), 236–250 (1996).
[CrossRef]

IEEE Photon. Technol. Lett.

K. Takada, M. Abe, M. Shibata, M. Ishii, and K. Okamoto, “Low-Crosstalk 10-GHz-spaced 512-channel arrayed-waveguide grating multi/demultiplexer fabricated on a 4-in wafer,” IEEE Photon. Technol. Lett. 13(11), 1182–1184 (2001).
[CrossRef]

G. Goldfarb, G. Li, and M. G. Taylor, “Orthogonal wavelength-division multiplexing using coherent detection,” IEEE Photon. Technol. Lett. 19(24), 2015–2017 (2007).
[CrossRef]

J. Lightwave Technol.

Opt. Express

A. J. Lowery and J. Armstrong, “Orthogonal-frequency-division multiplexing for dispersion compensation of long-haul optical systems,” Opt. Express 14(6), 2079–2084 (2006).
[CrossRef] [PubMed]

D. Hillerkuss, M. Winter, M. Teschke, A. Marculescu, J. Li, G. Sigurdsson, K. Worms, S. Ben Ezra, N. Narkiss, W. Freude, and J. Leuthold, “Simple all-optical FFT scheme enabling Tbit/s real-time signal processing,” Opt. Express 18(9), 9324–9340 (2010).
[CrossRef] [PubMed]

A. J. Lowery, “Design of arrayed-waveguide grating routers for use as optical OFDM demultiplexers,” Opt. Express 18(13), 14129–14143 (2010).
[CrossRef] [PubMed]

S. Chandrasekhar and X. Liu, “Experimental investigation on the performance of closely spaced multi-carrier PDM-QPSK with digital coherent detection,” Opt. Express 17(24), 21350–21361 (2009).
[CrossRef] [PubMed]

K. Lee, C. T. D. Thai, and J.-K. K. Rhee, “All optical discrete Fourier transform processor for 100 Gbps OFDM transmission,” Opt. Express 16(6), 4023–4028 (2008).
[CrossRef] [PubMed]

Y. Benlachtar, P. M. Watts, R. Bouziane, P. Milder, D. Rangaraj, A. Cartolano, R. Koutsoyannis, J. C. Hoe, M. Püschel, M. Glick, and R. I. Killey, “Generation of optical OFDM signals using 21.4 GS/s real time digital signal processing,” Opt. Express 17(20), 17658–17668 (2009).
[CrossRef] [PubMed]

Q. Yang, S. Chen, Y. Ma, and W. Shieh, “Real-time reception of multi-gigabit coherent optical OFDM signals,” Opt. Express 17(10), 7985–7992 (2009).
[CrossRef] [PubMed]

Opt. Lett.

Other

F. Buchali, R. Dischler, A. Klekamp, M. Bernhard, and Y. Ma, “Statistical Transmission Experiments Using a Real-Time 12.1 Gb/s OFDM Transmitter”, in Conference on Optical Fiber Communication, OFC (San Diego, CA, 2010), paper OMS3 (2010).

S. Chen, Y. Ma, and W. Shieh, 110-Gb/s Multi-Band Real-Time Coherent Optical OFDM Reception after 600-km Transmission over SSMF Fiber”, in Conference on Optical Fiber Communication, OFC (San Diego, CA, 2010), paper OMS2 (2010).

D. Hillerkuss, T. Schellinger, R. Schmogrow, M. Winter, T. Vallaitis, R. Bonk, A. Marculescu, J. Li, M. Dreschmann, J. Meyer, S. Ben Ezra, N. Narkiss, B. Nebendahl, F. Parmigiani, P. Petropoulos, B. Resan, K. Weingarten, T. Ellermeyer, J. Lutz, M. Möller, M. Hübner, J. Becker, C. Koos, W. Freude, and J. Leuthold, “Single source optical OFDM transmitter and optical FFT receiver demonstrated at line rates of 5.4 and 10.8Tb/s,” in Conference on Optical Fiber Communication, OFC (San Diego, CA, 2010), paper PDPC1 (2010).

F. C. Garcia Gunning, S. K. Ibrahim, P. Frascella, P. Gunning, and A. D. Ellis, “High symbol rate OFDM transmission technologies”,in Conference on Optical Fiber Communication, OFC (San Diego, CA, 2010), paper OThD1 (2010).

S. Chandrasekhar, X. Liu, B. Zhu, and D. W. Peckham, “Transmission of a 1.2 Tb/s 24-carrier no-guad-interval coherent OFDM superchannel over 7200-km of Ultra-Large-Area Fiber,” in Proc. ECOC 2009 (Vienna, Austria), paper PD2.6 (2009).

H. Sanjoh, E. Yamada, and Y. Yoshikuni, “Optical orthogonal frequency division multiplexing using frequency/time domain filtering for high spectral efficiency up to 1 bit/s/Hz,” in Conference on Optical Fiber Communication, OFC (Anaheim, CA, 2002), paper ThD1, 401–402 (2002).

W. Shieh and I. Djordjevic, OFDM for Optical Communications, Academic Press, 2009.

K. Takiguchi, M. Oguma, H. Takahashi, and A. Mori, “PLC-based eight-channel OFDM demultiplexer and its demonstration with 160 Gbit/s signal reception,” in Conference on Optical Fiber Communication, OFC (San Diego, CA, 2010), paper OThB4 (2010).

Y. Huang, D. Qian, R. E. Saperstein, P. N. Ji, N. Cvijetic, L. Xu, and T. Wang, “Dual-polarization 2x2 IFFT/FFT optical signal processing for 100-Gb/s QPSK-PDM all-optical OFDM,” in Conference on Optical Fiber Communication, OFC (San Diego, CA, 2009), paper OTuM4 (2009).

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Figures (10)

Fig. 1
Fig. 1

Schematic diagram of an OFDM transmission system with electronic IFFT and FFT. S/P: serial-to-parallel conversion. GI: Guard interval; DAC: Digital-to-analog converter; ADC: analog-to-digital converter; P/S: Parallel-to-serial conversion

Fig. 2
Fig. 2

Waveguide structure of an AWG (a) the whole structure (b) the enlarged picture of the output slab region [17].

Fig. 3
Fig. 3

Configuration of the AWG to realize the operations of (a) FFT and (b) IFFT

Fig. 4
Fig. 4

Theoretical and experimental spectrum of different channels of a cyclic AWG (a) theoretical calculation (b) experimental measurements. Both the spectra have a FSR of 160GHz, and channel spacing of 10GHz. (c) The spectral transmittance of a 32-channel AWG experimentally demonstrated in [19], with 10GHz channel spacing

Fig. 5
Fig. 5

The proposed AWG-based all-optical OFDM system setup. MLL: mode locked laser; EDFA: erbium-doped fiber amplifier; S: optical sampler. The AWG at the transmitter performs IFFT and the one at the receiver performs FFT.

Fig. 6
Fig. 6

Eye diagrams of the demultiplexed OFDM signal at the receiver end in Fig. 5 for (a) N = 4 (b) N = 16

Fig. 7
Fig. 7

(a) The generated optical OFDM signal waveform after the transmitter in Fig. 5; (b) the schematic of OFDM signal demultiplexing process in the system shown in Fig. 5

Fig. 8
Fig. 8

The modified AWG-based all-optical OFDM system setup. MLL: mode locked laser; EDFA: erbium-doped fiber amplifier; S: optical sampler. The AWG at the transmitter performs WDM demultiplexing and the one at the receiver performs FFT.

Fig. 9
Fig. 9

Eye diagrams of the demultiplexed OFDM signal at the receiver end in Fig. 7 for (a) N = 4 (b) N = 16

Fig. 10
Fig. 10

Eye diagrams of the demultiplexed OFDM signal with 50GHz modulator bandwidth in Fig. 7 for N = 16 (a) the modulated subcarrers are symbol-aligned (b) the modulated subcarriers are not symbol-aligned

Equations (14)

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2 π n s ( λ 0 ) λ 0 ( f 1 x 1 d 1 2 f 1 ) + 2 π n s ( λ 0 ) λ 0 ( f + x d 2 f ) = 2 π n s ( λ 0 ) λ 0 ( f 1 + x 1 d 1 2 f 1 ) + 2 π n s ( λ 0 ) λ 0 ( f x d 2 f ) + 2 π n c ( λ 0 ) λ 0 Δ L + 2 m π ,
λ 0 = n c Δ L m ,          Δ λ = n s d D λ 0 N c f Δ L ,        N c h = λ 0 f n s d D ,
Δ f = c λ 0 2 Δ λ = n s d D f λ 0 c Δ L N c = 1 N c h 1 τ ,       τ = Δ L N c c .
h i k ( t ) = m = 0 N 1 exp [ π j n s d λ 0 ( 2 m N + 1 ) ( sin θ i + sin θ o ) ] δ ( t n s f c N c L + m Δ L c )                                                                                                    ( m = 0 , 1 , ... , N 1 ) .
sin θ i ( 2 i N + 1 ) D 2 f ,      sin θ o ( 2 k N + 1 ) D 2 f .
h i k ( t ) = m = 0 N 1 e j π n s d D λ 0 f ( 2 m N + 1 ) ( i + k + 1 ) δ ( t m τ ) = m = 0 N 1 e j π N c h ( 2 m N + 1 ) ( i + k + 1 ) δ ( t m τ )          = m = 0 N 1 e j π N ( 2 m N + 1 ) ( i + k + 1 ) δ ( t m τ )                                  ( m = 0 , 1 , ,   N 1 )  
θ j , k = 2 π n s d D λ 0 f ( m N + 1 2 ) k .
S k ( t ) = s i ( τ ) h ( t τ ) d τ = m = 0 N 1 e j 2 π N ( m N 1 2 ) k s i ( t m τ ) .
S k [ ( N 1 ) τ ] = m = 0 N 1 e j 2 π N ( N 1 2 m ) k s i ( m τ )                      n = N / 2 m ¯ ¯   ( n = 0 N 1 s i ' [ ( N 2 n ) τ ] e j 2 π n k N ) e j π N k = F F T ( s i ' [ ( N 2 n ) τ ] ) e j π N k .
h i ( t ) = m = 0 N 1 exp j 2 π N ( m N 1 2 ) i δ ( t m τ ) .
S i ( t ) = { S i ( m T ) ,          t = m T 0 ,                   o t h e r w i s e
s o u t ( t ) = i = 0 N 1 S i ( τ ) h i ( t τ ) d τ .
                       s o u t ( m τ ) = i = 0 N 1 e j 2 π N ( m N 1 2 ) i S i ( 0 ) = i = 0 N 1 S i ( 0 ) e j 2 π N ( N 1 2 ) i e j 2 π m i N n = N / 2 + m    s ' o u t [ ( n + N 2 ) τ ]   =   i = 0 N 1 S i ( 0 ) e j π N i e j 2 π n i N = I F F T ( S i ( 0 ) e j π N i ) .
H i k ( f ) = e j π ( N 1 ) f τ m = 0 N 1 e j π ( 2 m + N 1 ) ( i + k + 1 N + f τ ) = e j π ( N 1 ) f τ sin [ π ( i + k 1 + N f τ ) ] sin [ π ( i + k 1 ) / N + f τ ] .

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