Abstract

Digital signal processing (DSP)-based coherent communications have become standard for future high-speed optical networks. Implementing DSP-based advanced algorithms for data detection requires much more detailed knowledge of the transmission link parameters, resulting in optical performance monitoring (OPM) being even more important for next generation systems. At the same time, the DSP platform also enables new strategies for OPM. In this paper, we propose the use of pilot symbols with alternating power levels and study the statistics of the received power and phase difference to simultaneously and independently monitor the carrier frequency offset between transmitter and receiver laser, laser linewidth, number of spans, fiber nonlinearity parameters as well as optical signal-to-noise ratio (OSNR) of a transmission link. Analytical predictions are verified by simulation results for systems with full chromatic dispersion (CD) compensation per span and 10% CD under-compensation per span. In addition, we show that by monitoring the changes in the statistics of the received pilot symbols during network operation, one can locate faults or OSNR degradations along a transmission link without additional monitoring equipments at intermediate nodes, which may be useful for more efficient dynamic routing and network management.

© 2010 OSA

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    [CrossRef]
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    [CrossRef]
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    [CrossRef]
  23. M. Khair, B. Kantarci, J. Zheng, and H. T. Mouftah, “Optimization for Fault Localization in All-Optical Networks,” J. Lightwave Technol. 27(21), 4832–4840 (2009).
    [CrossRef]

2010 (2)

Z. Q. Pan, C. Y. Yu, and A. E. Willner, “Optical performance monitoring for the next generation optical communication networks,” Opt. Fiber Technol. 16(1), 20–45 (2010).
[CrossRef]

Y. Cao, S. Yu, J. Shen, W. Gu, and Y. Ji, “Frequency Estimation for Optical Coherent MPSK System Without Removing Modulated Data Phase,” IEEE Photon. Technol. Lett. 22(10), 691–693 (2010).
[CrossRef]

2009 (4)

2008 (2)

2007 (2)

A. V. Sichani and H. T. Mouftah, “Limited-perimeter vector matching fault-localization protocol for transparent all-optical communication networks,” IET Communications 1(3), 472–478 (2007).
[CrossRef]

A. P. T. Lau and J. M. Kahn, “Signal design and detection in presence of nonlinear phase noise,” J. Lightwave Technol. 25(10), 3008–3016 (2007).
[CrossRef]

2006 (1)

2005 (2)

Y. G. Wen, V. W. S. Chan, and L. Z. Zheng, “Efficient fault-diagnosis algorithms for all-optical WDM networks with probabilistic link failures,” J. Lightwave Technol. 23(10), 3358–3371 (2005).
[CrossRef]

M. N. Petersen and M. L. Nielsen, “Experimental and theoretical demonstration of launch power optimisation using subcarrier fibre nonlinearity monitor,” Electron. Lett. 41(5), 268–269 (2005).
[CrossRef]

2004 (1)

2002 (1)

1995 (1)

1994 (1)

1993 (1)

L. Prigent and J. P. Hamaide, “Measurement of Fiber Nonlinear Kerr Coefficient by four-Wave-Mixing,” IEEE Photon. Technol. Lett. 5(9), 1092–1095 (1993).
[CrossRef]

Cao, Y.

Y. Cao, S. Yu, J. Shen, W. Gu, and Y. Ji, “Frequency Estimation for Optical Coherent MPSK System Without Removing Modulated Data Phase,” IEEE Photon. Technol. Lett. 22(10), 691–693 (2010).
[CrossRef]

Chan, V. W. S.

Clarici, G.

T. Duthel, G. Clarici, C. R. S. Fludger, J. C. Geyer, C. Schulien, and S. Wiese, “Laser Linewidth Estimation by Means of Coherent Detection,” IEEE Photon. Technol. Lett. 21(20), 1568–1570 (2009).
[CrossRef]

Duthel, T.

T. Duthel, G. Clarici, C. R. S. Fludger, J. C. Geyer, C. Schulien, and S. Wiese, “Laser Linewidth Estimation by Means of Coherent Detection,” IEEE Photon. Technol. Lett. 21(20), 1568–1570 (2009).
[CrossRef]

Fludger, C. R. S.

T. Duthel, G. Clarici, C. R. S. Fludger, J. C. Geyer, C. Schulien, and S. Wiese, “Laser Linewidth Estimation by Means of Coherent Detection,” IEEE Photon. Technol. Lett. 21(20), 1568–1570 (2009).
[CrossRef]

Geyer, J. C.

T. Duthel, G. Clarici, C. R. S. Fludger, J. C. Geyer, C. Schulien, and S. Wiese, “Laser Linewidth Estimation by Means of Coherent Detection,” IEEE Photon. Technol. Lett. 21(20), 1568–1570 (2009).
[CrossRef]

Gu, W.

Y. Cao, S. Yu, J. Shen, W. Gu, and Y. Ji, “Frequency Estimation for Optical Coherent MPSK System Without Removing Modulated Data Phase,” IEEE Photon. Technol. Lett. 22(10), 691–693 (2010).
[CrossRef]

Hamaide, J. P.

L. Prigent and J. P. Hamaide, “Measurement of Fiber Nonlinear Kerr Coefficient by four-Wave-Mixing,” IEEE Photon. Technol. Lett. 5(9), 1092–1095 (1993).
[CrossRef]

Haunstein, H.

Ho, K. P.

Ip, E.

Ji, Y.

Y. Cao, S. Yu, J. Shen, W. Gu, and Y. Ji, “Frequency Estimation for Optical Coherent MPSK System Without Removing Modulated Data Phase,” IEEE Photon. Technol. Lett. 22(10), 691–693 (2010).
[CrossRef]

Kahn, J. M.

Kantarci, B.

Kato, T.

Khair, M.

Kim, K. S.

Lau, A. P. T.

Li, G. F.

Liu, X.

Mateo, E. F.

Mayrock, M.

Mouftah, H. T.

M. Khair, B. Kantarci, J. Zheng, and H. T. Mouftah, “Optimization for Fault Localization in All-Optical Networks,” J. Lightwave Technol. 27(21), 4832–4840 (2009).
[CrossRef]

A. V. Sichani and H. T. Mouftah, “Limited-perimeter vector matching fault-localization protocol for transparent all-optical communication networks,” IET Communications 1(3), 472–478 (2007).
[CrossRef]

Nielsen, M. L.

M. N. Petersen and M. L. Nielsen, “Experimental and theoretical demonstration of launch power optimisation using subcarrier fibre nonlinearity monitor,” Electron. Lett. 41(5), 268–269 (2005).
[CrossRef]

Nishimura, M.

Pan, Z. Q.

Z. Q. Pan, C. Y. Yu, and A. E. Willner, “Optical performance monitoring for the next generation optical communication networks,” Opt. Fiber Technol. 16(1), 20–45 (2010).
[CrossRef]

Petersen, M. N.

M. N. Petersen and M. L. Nielsen, “Experimental and theoretical demonstration of launch power optimisation using subcarrier fibre nonlinearity monitor,” Electron. Lett. 41(5), 268–269 (2005).
[CrossRef]

Prigent, L.

L. Prigent and J. P. Hamaide, “Measurement of Fiber Nonlinear Kerr Coefficient by four-Wave-Mixing,” IEEE Photon. Technol. Lett. 5(9), 1092–1095 (1993).
[CrossRef]

Quoi, K. W.

Rabbani, S.

Reed, W. A.

Sasaoka, E.

Schulien, C.

T. Duthel, G. Clarici, C. R. S. Fludger, J. C. Geyer, C. Schulien, and S. Wiese, “Laser Linewidth Estimation by Means of Coherent Detection,” IEEE Photon. Technol. Lett. 21(20), 1568–1570 (2009).
[CrossRef]

Shen, J.

Y. Cao, S. Yu, J. Shen, W. Gu, and Y. Ji, “Frequency Estimation for Optical Coherent MPSK System Without Removing Modulated Data Phase,” IEEE Photon. Technol. Lett. 22(10), 691–693 (2010).
[CrossRef]

Sichani, A. V.

A. V. Sichani and H. T. Mouftah, “Limited-perimeter vector matching fault-localization protocol for transparent all-optical communication networks,” IET Communications 1(3), 472–478 (2007).
[CrossRef]

Stolen, R. H.

Suetsugu, Y.

Takagi, M.

Wen, Y. G.

Wiese, S.

T. Duthel, G. Clarici, C. R. S. Fludger, J. C. Geyer, C. Schulien, and S. Wiese, “Laser Linewidth Estimation by Means of Coherent Detection,” IEEE Photon. Technol. Lett. 21(20), 1568–1570 (2009).
[CrossRef]

Willner, A. E.

Z. Q. Pan, C. Y. Yu, and A. E. Willner, “Optical performance monitoring for the next generation optical communication networks,” Opt. Fiber Technol. 16(1), 20–45 (2010).
[CrossRef]

Xu, C.

Yu, C. Y.

Z. Q. Pan, C. Y. Yu, and A. E. Willner, “Optical performance monitoring for the next generation optical communication networks,” Opt. Fiber Technol. 16(1), 20–45 (2010).
[CrossRef]

Yu, S.

Y. Cao, S. Yu, J. Shen, W. Gu, and Y. Ji, “Frequency Estimation for Optical Coherent MPSK System Without Removing Modulated Data Phase,” IEEE Photon. Technol. Lett. 22(10), 691–693 (2010).
[CrossRef]

Zheng, J.

Zheng, L. Z.

Appl. Opt. (1)

Electron. Lett. (1)

M. N. Petersen and M. L. Nielsen, “Experimental and theoretical demonstration of launch power optimisation using subcarrier fibre nonlinearity monitor,” Electron. Lett. 41(5), 268–269 (2005).
[CrossRef]

IEEE Photon. Technol. Lett. (3)

Y. Cao, S. Yu, J. Shen, W. Gu, and Y. Ji, “Frequency Estimation for Optical Coherent MPSK System Without Removing Modulated Data Phase,” IEEE Photon. Technol. Lett. 22(10), 691–693 (2010).
[CrossRef]

T. Duthel, G. Clarici, C. R. S. Fludger, J. C. Geyer, C. Schulien, and S. Wiese, “Laser Linewidth Estimation by Means of Coherent Detection,” IEEE Photon. Technol. Lett. 21(20), 1568–1570 (2009).
[CrossRef]

L. Prigent and J. P. Hamaide, “Measurement of Fiber Nonlinear Kerr Coefficient by four-Wave-Mixing,” IEEE Photon. Technol. Lett. 5(9), 1092–1095 (1993).
[CrossRef]

IET Communications (1)

A. V. Sichani and H. T. Mouftah, “Limited-perimeter vector matching fault-localization protocol for transparent all-optical communication networks,” IET Communications 1(3), 472–478 (2007).
[CrossRef]

J. Lightwave Technol. (8)

Opt. Fiber Technol. (1)

Z. Q. Pan, C. Y. Yu, and A. E. Willner, “Optical performance monitoring for the next generation optical communication networks,” Opt. Fiber Technol. 16(1), 20–45 (2010).
[CrossRef]

Opt. Lett. (3)

Other (5)

T. Tanimura, et al., “Digital clock recovery algorithm for optical coherent receivers operating independent of laser frequency offset,” in 34th European Conference on Optical Communication (ECOC), (2008), Paper Mo.3.D.2.

S. Zhang, et al., “Novel ultra wide-range frequency offset estimation for digital coherent optical receiver,” in Optical Fiber Communication/National Fiber Optic Engineers Conference, (OFC/NFOEC), 2010, Paper OWV3.

T. Takahito, et al., “Semi-Blind Nonlinear Equalization in Coherent Multi-Span Transmission System with Inhomogeneous Span Parameters,” in Optical Fiber Communication/National Fiber Optic Engineers Conference, (OFC/NFOEC), 2010, Paper OMR6.

J. H. Park, J. S. Baik, and C. H. Lee, “Fault-localization in WDM-PONs,” in Optical Fiber Communication/National Fiber Optic Engineers Conference (OFC/NFOEC), 2006, Paper JThB79.

S. S. Ahuja, S. Ramasubramanian, and M. Krunz, “Single-Link Failure Detection in All-Optical Networks using Monitoring Cycles and Paths,” IEEE/ACM Transactions on Networking, 17, 1080–1093 (2009).

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Figures (6)

Fig. 1
Fig. 1

(a) In a dynamic optical network with ROADMs, signal may travel through different routes even for a given source and destination. This results in variations of the number of spans N as well as other parameters of the overall transmission link. (b) Q-factor vs. launch power for a NRZ-16-QAM system with length 1600 km and 10% CD under-compensation per span. System performance is sensitive to the accuracies of the parameters used in BP.

Fig. 2
Fig. 2

A coherent communication system setup with optical CD compensation

Fig. 3
Fig. 3

A sequence of pilot symbols with alternating power levels P 1 and P 2 for the monitoring of laser linewidth, frequency offset, number of spans, fiber nonlinear parameters and OSNR of the link. The received signal is sampled at a rate of 1 / T s and the symbol rate 1/T is low enough such that the transmitted signal E(t) does not undergo any pulse shape distortion due to CD and/or PMD.

Fig. 4
Fig. 4

(a) Estimated frequency offset vs. true frequency offset (b) Estimated laser linewidth vs. true laser linewidth for a 15-span system. Samples from 10 6 symbols are used for each estimate and the error bars indicate standard deviations of 10 independent estimates.

Fig. 5
Fig. 5

(a) Estimated N vs. true N. (b) Estimated OSNR vs. true OSNR. (c) Estimated Λ D vs. true Λ D . Samples from 10 6 symbols are used for each estimate and the error bars indicate standard deviations of 10 independent estimates. The frequency offset and laser linewidth are 200 MHz and 100 kHz respectively.

Fig. 6
Fig. 6

Change in variance of phase difference Δ σ Δ ϕ 2 ( 1 ) vs. fault location with Δ σ i 2 = , 8 and 10 dB for a 20-span link. Samples from 10 6 symbols are used for each estimate and the error bars indicate standard deviations of 10 independent estimates.

Tables (1)

Tables Icon

Table 1 Channel parameters used in simulations

Equations (22)

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S S ( D ) ( f ) = n s p h v ( e α S ( D ) L S ( D ) 1 )
P ( t ) = | P k + i = 1 N ( n S i ( t ) + n D i ( t ) ) | 2 P k + 2 P k Re { i = 1 N ( n S i ( t ) + n D i ( t ) ) }       for  k = 1 , 2
σ p o w e r 2 ( P k ) = Ε [ P 2 ( t ) ] Ε [ P ( t ) ] 2 = E [ P k 2 + 4 P k P k Re { i = 1 N ( n S i ( t ) + n D i ( t ) ) } + 4 P k ( i = 1 N Re { n S i ( t ) + n D i ( t ) } ) 2 ] P k 2 = 2 P k N ( σ S 2 + σ D 2 )                                                                                for  k = 1 , 2.    
ϕ ( t ) = ϕ A S E ( t ) + ϕ N L ( t ) + ϕ T x ( t ) + ϕ R x ( t ) + 2 π Δ f o f f t + θ  
ϕ ASE ( t ) Im { i = 1 N [ n S i ( t ) + n D i ( t ) ] } P k for k = 1 , 2
σ A S E 2 ( P k ) = N 2 P k ( σ S 2 + σ D 2 )                           for  k = 1 , 2.
ϕ N L ( t ) = Λ S | P k | 2 + Λ D | P k + n S 1 ( t ) | 2                 + Λ S | P k + n S 1 ( t ) + n D 1 ( t ) | 2 + Λ D | P k + n S 1 ( t ) + n D 1 ( t ) + n S 2 ( t ) | 2 +                 + Λ S | P k + n S 1 ( t ) + n S N 1 ( t ) + n D 1 ( t ) + + n D N 1 ( t ) | 2                 + Λ D | P k + n S 1 ( t ) + n S N ( t ) + n D 1 ( t ) + + n D N 1 ( t ) | 2             = i = 1 N ( Λ D | P k + l = 1 i n S l ( t ) + m = 1 i 1 n D m ( t ) | 2 + Λ S | P k + m = 1 i 1 n S m ( t ) + m = 1 i 1 n D m ( t ) | 2 )             i = 1 N Λ D ( P k + 2 P k Re { l = 1 i n S l ( t ) + m = 1 i 1 n D m ( t ) } )                + i = 1 N Λ S ( P k + 2 P k Re { l = 1 i 1 n S l ( t ) + m = 1 i 1 n D m ( t ) } )                         for  k = 1 , 2.
ϕ N L ( P k ) ¯ = P k N ( Λ S + Λ D )                           for  k = 1 , 2
σ N L 2 ( P k ) = Ε [ ϕ N L 2 ( P k ) ] Ε [ ϕ N L ( P k ) ] 2              = 2 P k ( Λ S + Λ D ) 2 σ D 2 [ ( N 1 ) 2 + ( N 2 ) 2 + + 1 ]                 + 2 P k σ S 2 { [ Λ S ( N 1 ) + Λ D N ] 2 + [ Λ S ( N 2 ) + Λ D ( N 1 ) ] 2 + + Λ D 2 }              = 2 P k ( Λ S + Λ D ) 2 σ D 2 i = 1 N 1 i 2 + 2 P k σ S 2 ( Λ S 2 i = 1 N 1 i 2 + Λ D 2 i = 1 N i 2 )                 + 4 Λ S Λ D P k σ S 2 i = 0 N 1 ( N i ) 2 4 Λ S Λ D P k σ S 2 i = 0 N 1 ( N i )               for  k = 1 , 2.
σ N L 2 ( P k ) = 2 P k ( Λ S + Λ D ) 2 σ D 2 N ( N 1 ) ( 2 N 1 ) 6                 + 2 P k σ S 2 [ Λ S 2 N ( N 1 ) ( 2 N 1 ) 6 + Λ D 2 N ( N + 1 ) ( 2 N + 1 ) 6 ]                 + 4 Λ S Λ D P k σ S 2 [ N ( N + 1 ) ( 2 N + 1 ) 6 N ( N + 1 ) 2 ]              = 2 P k ( Λ S + Λ D ) 2 ( σ S 2 + σ D 2 ) ( 1 3 N 3 1 2 N 2 + 1 6 N )                 + 2 P k σ S 2 [ Λ D 2 N 2 + Λ S Λ D ( N 2 N ) ]                                       for  k = 1 , 2.
E [ e j ( ϕ T x ( R x ) ( t 1 ) ϕ T x ( R x ) ( t 2 ) ) ] = exp ( π Δ f L W | t 1 t 2 | ) .
σ L W 2 = 2 π Δ f L W | t 1 t 2 | .
Δ ϕ ( w 1 ) = ϕ ( t + w 1 T s ) ϕ ( t )       = [ ϕ A S E ( t ) + ϕ N L ( t ) + ϕ T x ( t ) + ϕ R x ( t ) ] -                [ ϕ A S E ( t + w 1 T s ) + ϕ N L ( t + w 1 T s ) + ϕ T x ( t + w 1 T s ) + ϕ R x ( t + w 1 T s ) ] + 2 π Δ f o f f w 1 T s  
Δ ϕ ( w 1 ) ¯ = 2 π Δ f o f f w 1 T s
σ Δ ϕ , k 2 ( w 1 ) = 2 σ N L 2 ( P k ) + 2 σ A S E 2 ( P k ) + 2 × 2 π Δ f L W w 1 T s
σ Δ ϕ , k 2 ( w 1 ) σ Δ ϕ , k 2 ( w 2 ) = 2 × 2 π Δ f L W ( w 1 w 2 ) T s
Δ f o f f = Δ ϕ ¯ ( w 1 ) 2 π w 1 T s  
Δ f L W = σ Δ ϕ , k 2 ( w 2 ) σ Δ ϕ , k 2 ( w 1 ) 4 π ( w 2 w 1 ) T s
Δ ϕ ( η ) ¯ = ( P 2 P 1 ) N ( Λ S + Λ D ) +2 π Δ f o f f T
2( P 1 + P 2 ) σ S 2 ( Λ S 2 Λ S Λφ(η) ¯ P 1 P 2 ) N 3 +[ ( P 1 + P 2 ) Λφ(η) ¯ 2 σ power 2 ( P 1 ) 3 ( P 1 P 2 ) 2 P 1 +2( P 1 + P 2 ) σ S 2 Λφ(η) ¯ 2 ( P 1 P 2 ) 2 2( P 1 + P 2 ) Λ S σ S 2 Δφ(η) ¯ P 1 P + σ power 2 ( P 1 ) 4 P 1 ( 1 P 1 + 1 P 2 )( σ Δφ,1 2 ( w 1 )+ σ Δφ,2 2 ( w 2 ) ) ] N 2 ( P 1 + P 2 ) Δφ(η) ¯ 2 σ power 2 ( P 1 ) 2 P 1 ( P 1 P 2 ) 2 N+ ( P 1 + P 2 ) Δφ(η) ¯ 2 σ power 2 ( P 1 ) 6 P 1 ( P 1 P 2 ) 2 =0
Λ D = Δ ϕ ( η ) ¯ -2 π Δ f o f f T ( P 1 P 2 ) N  - Λ S
OSNR = P k N ( σ S 2 + σ D 2 ) = P k σ p o w e r 2 2 P k = 2 P k 2 σ p o w e r 2                      for  k = 1 , 2.

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