## Error vector magnitude based parameter estimation for digital filter back-propagation mitigating SOA distortions in 16-QAM |

Optics Express, Vol. 21, Issue 17, pp. 20376-20386 (2013)

http://dx.doi.org/10.1364/OE.21.020376

Acrobat PDF (4829 KB)

### Abstract

We investigate the performance of digital filter back-propagation (DFBP) using coarse parameter estimation for mitigating SOA nonlinearity in coherent communication systems. We introduce a simple, low overhead method for parameter estimation for DFBP based on error vector magnitude (EVM) as a figure of merit. The bit error rate (BER) penalty achieved with this method has negligible penalty as compared to DFBP with fine parameter estimation. We examine different bias currents for two commercial SOAs used as booster amplifiers in our experiments to find optimum operating points and experimentally validate our method. The coarse parameter DFBP efficiently compensates SOA-induced nonlinearity for both SOA types in 80 km propagation of 16-QAM signal at 22 Gbaud.

© 2013 OSA

## 1. Introduction

1. C. R. Doerr, “High performance photonic integrated circuits for coherent fiber communication,” in *Optical Fiber Communication Conference*, OSA Technical Digest (Optical Society of America, 2010), paper OWU5. http://www.opticsinfobase.org/abstract.cfm?URI=OFC-2010-OWU5 [CrossRef]

2. G. Contestabile, Y. Yoshida, A. Maruta, and K. Kitayama, “100 nm-bandwidth positive-efficiency wavelength conversion for m-PSK and m-QAM signals in QD-SOA,” in *Optical Fiber Communication Conference*, OSA Technical Digest (Optical Society of America, 2013), paper OTh1C.6. http://www.opticsinfobase.org/abstract.cfm?URI=OFC-2013-OTh1C.6 [CrossRef]

3. C. Porzi, A. Bogoni, and G. Contestabile, “Regeneration of DPSK signals in a saturated SOA,” IEEE Photon. Technol. Lett. **24**(18), 1597–1599 (2012). [CrossRef]

4. A. Ghazisaeidi, F. Vacondio, A. Bononi, and L. A. Rusch, “SOA intensity noise suppression: A Multicanonical Monte Carlo simulator of extremely low BER,” J. Lightwave Technol. **27**(14), 2667–2677 (2009). [CrossRef]

5. Z. Li, Y. Dong, J. Mo, Y. Wang, and C. Lu, “1050-kmWDM transmission of 8×10.709Gb/s DPSK signal using cascaded in-line semiconductor optical amplifiers,” IEEE Photon. Technol. Lett. **16**(7), 1760–1762 (2004). [CrossRef]

9. D. Zimmerman and L. Spiekman, “Amplifiers for the masses: EDFA, EDWA, and SOA amplets for metro and access applications,” J. Lightwave Technol. **22**(1), 63–70 (2004). [CrossRef]

10. T. Yasui, Y. Shibata, K. Tsuzuki, N. Kikuchi, Y. Kawaguchi, M. Arai, and H. Yasaka, “Lossless 10-Gbit/s InP n-p-i-n Mach-Zehnder modulator monolithically integrated with semiconductor optical amplifier,” in *Optical Fiber Communication Conference*, OSA Technical Digest (Optical Society of America, 2008), paper OThC5. http://www.opticsinfobase.org/abstract.cfm?URI=OFC-2008-OThC5 [CrossRef]

11. A. Nakanishi, N. Sasada, Y. Sakuma, R. Washino, K. Okamoto, H. Hayashi, H. Arimoto, and S. Tanaka, “Uncooled (0 to 85°C) and full C-band operation of a 10.7 Gbit/s InP Mach-Zehnder modulator monolithically integrated with SOA,” in *Optical Fiber Communication Conference*, OSA Technical Digest (Optical Society of America, 2013), paper OW1G.3. http://www.opticsinfobase.org/abstract.cfm?URI=OFC-2013-OW1G.3

12. N. Kamitani, Y. Yoshida, and K. Kitayama, “Experimental study on impact of SOA nonlinear phase noise in 40Gbps coherent 16QAM transmissions,” in *European Conference and Exhibition on Optical Communication*, OSA Technical Digest (Optical Society of America, 2012), paper P1.04. http://www.opticsinfobase.org/abstract.cfm?URI=ECEOC-2012-P1.04 [CrossRef]

13. A. Ghazisaeidi and L. A. Rusch, “On the efficiency of digital back-propagation for mitigating SOA-induced nonlinear impairments,” J. Lightwave Technol. **29**(21), 3331–3339 (2011). [CrossRef]

18. S. Lange, Y. Yoshida, and K. Kitayama, “ A low-complexity digital pre-compensation of SOA induced phase distortion in coherent QAM transmissions,” in *Optical Fiber Communication Conference*, OSA Technical Digest (Optical Society of America, 2013), paper OTh3C.7. http://www.opticsinfobase.org/abstract.cfm?URI=OFC-2013-OTh3C.7

13. A. Ghazisaeidi and L. A. Rusch, “On the efficiency of digital back-propagation for mitigating SOA-induced nonlinear impairments,” J. Lightwave Technol. **29**(21), 3331–3339 (2011). [CrossRef]

14. S. Amiralizadeh, A. T. Nguyen, C.-S. Park, A. Ghazisaeidi, and L. A. Rusch, “Experimental validation of digital filter back-propagation to suppress SOA-induced nonlinearities in 16-QAM,” in *Optical Fiber Communication Conference*, OSA Technical Digest (Optical Society of America, 2013), paper OM2B.2. http://www.opticsinfobase.org/abstract.cfm?URI=OFC-2013-OM2B.2 [CrossRef]

14. S. Amiralizadeh, A. T. Nguyen, C.-S. Park, A. Ghazisaeidi, and L. A. Rusch, “Experimental validation of digital filter back-propagation to suppress SOA-induced nonlinearities in 16-QAM,” in *Optical Fiber Communication Conference*, OSA Technical Digest (Optical Society of America, 2013), paper OM2B.2. http://www.opticsinfobase.org/abstract.cfm?URI=OFC-2013-OM2B.2 [CrossRef]

## 2. EVM based parameter estimation of DFBP

13. A. Ghazisaeidi and L. A. Rusch, “On the efficiency of digital back-propagation for mitigating SOA-induced nonlinear impairments,” J. Lightwave Technol. **29**(21), 3331–3339 (2011). [CrossRef]

14. S. Amiralizadeh, A. T. Nguyen, C.-S. Park, A. Ghazisaeidi, and L. A. Rusch, “Experimental validation of digital filter back-propagation to suppress SOA-induced nonlinearities in 16-QAM,” in *Optical Fiber Communication Conference*, OSA Technical Digest (Optical Society of America, 2013), paper OM2B.2. http://www.opticsinfobase.org/abstract.cfm?URI=OFC-2013-OM2B.2 [CrossRef]

**29**(21), 3331–3339 (2011). [CrossRef]

19. B. Filion, A. Ghazisaeidi, L. A. Rusch, and S. Larochelle, “Extraction of semiconductor optical amplifier parameters for wavelength conversion modeling,” in *Proceedings of IEEE Photonics Conference* (Institute of Electrical and Electronics Engineers, Arlington, 2011), pp. 367–368. [CrossRef]

*Optical Fiber Communication Conference*, OSA Technical Digest (Optical Society of America, 2013), paper OM2B.2. http://www.opticsinfobase.org/abstract.cfm?URI=OFC-2013-OM2B.2 [CrossRef]

### 2.1 DFBP parameters

20. A. Saleh, “Nonlinear models of travelling-wave optical amplifiers,” Electron. Lett. **24**(14), 835–837 (1988). [CrossRef]

*E*(

_{in}*t*) and

*E*(

_{out}*t*) are respectively the SOA input and output fields,

*α*is the linewidth enhancement factor and

*h*(

*t*) represents the gain exponent or integrated material gain. The following SOA dynamic gain equation can be solved to find

*h*(

*t*):where

*h*

_{0},

*P*and

_{sat}*τ*are the unsaturated gain exponent, the saturation power and the carrier lifetime, respectively. Therefore, knowledge of

_{c}*h*

_{0},

*α*,

*P*and

_{sat}*τ*enables us to model the relationship between the SOA input and output fields. These four values are the parameter set describing SOA behavior and those needed to implement the DFBP. The input power |

_{c}*E*|

_{in}^{2}can be easily measured.

**29**(21), 3331–3339 (2011). [CrossRef]

15. F. Vacondio, A. Ghazisaeidi, A. Bononi, and L. A. Rusch, “Low-complexity compensation of SOA nonlinearity for single-channel PSK and OOK,” J. Lightwave Technol. **28**(3), 277–288 (2010). [CrossRef]

*h*(

*t*) is assumed to be equal to the sum of the average gain exponent and zero-average fluctuations, i.e.,

*h*

_{0}is introduced to implement an “inverse SOA”. Let Δ

*t*be the sampling period, which is equal to symbol time since the DFBP input signal is one sample per symbol in our implementation (oversampling factor = 1). As shown in the DFBP block diagram in Fig. 1, we find the zero-average fluctuations,

*δh*(

*t*), using a digital filter which is derived from the linearized SOA model by taking z-transform [13

**29**(21), 3331–3339 (2011). [CrossRef]

*c*

_{1}and

*c*

_{2}, from the SOA parameter set and the easily measured input power |

*E*|

_{in}^{2}via whereHaving found

*h*(

*t*), the compensated output is found by multiplying the input by

### 2.2 DFBP parameter estimation

*h*

_{0},

*α*,

*P*and

_{sat}*τ*Previous examination has shown that DFBP performance is almost independent of

_{c}.*h*

_{0}[14

*Optical Fiber Communication Conference*, OSA Technical Digest (Optical Society of America, 2013), paper OM2B.2. http://www.opticsinfobase.org/abstract.cfm?URI=OFC-2013-OM2B.2 [CrossRef]

*h*

_{0}at a typical value of 4.6. In our experimental examination of both linear and nonlinear SOAs there is little variation in

*α*and we fix it at

*α*= 4.2. With two of the parameters fixed, the DFBP performance now mainly depends on

*P*and

_{sat}*τ*.

_{c}21. R. Schmogrow, B. Nebendahl, M. Winter, A. Josten, D. Hillerkuss, S. Koenig, J. Meyer, M. Dreschmann, M. Huebner, C. Koos, J. Becker, W. Freude, and J. Leuthold, “Error vector magnitude as a performance measure for advanced modulation formats,” IEEE Photon. Technol. Lett. **24**(1), 61–63 (2012). [CrossRef]

*E*,

_{i}*E*and

_{0,i}*N*are received symbol, ideal constellation point for received symbol and number of randomly transmitted data. The EVM figure of merit does not require knowledge of transmitted bits thus enabling blind adaptation. We propose the use of EVM for optimization of

*P*and

_{sat}*τ*in a computationally simple manner and show via simulation and experiment that such an optimization leads to significant BER improvement.

_{c}*h*

_{0},

*α*and search over 45 possibilities for (

*P*,

_{sat}*τ*), i.e., 9 for

_{c}*τ*and 5 for

_{c}*P*as shown in Fig. 1. Our spread of values (

_{sat}*P*,

_{sat}*τ*), covers a wide gamut of possibilities for linear and nonlinear SOAs. One might limit them having knowledge about SOA parameters. For each pair, the DFBP block compensates for SOA nonlinearity. We then perform phase recovery and minimum mean square error (MMSE) equalization for those 4000 symbols and calculate EVM. At the end, we choose the parameter pair corresponding to minimum EVM.

_{c}### 2.3 SOA characterization

22. D. Cassioli, S. Scotti, and A. Mecozzi, “A time-domain computer simulator of the nonlinear response of semiconductor optical amplifiers,” IEEE J. Quantum Electron. **36**(9), 1072–1080 (2000). [CrossRef]

*K*small sections for greater accuracy. The SOA distributed loss and amplified spontaneous emission (ASE) is included in this model. The propagation equations are solved using Runge-Kutta fourth order algorithm when

*K*= 80 as “ground truth”. For back-propagation, we set

*K*= 1 (one inverse gain block) to reduce complexity, as it has been shown this causes minimal penalty [14

*Optical Fiber Communication Conference*, OSA Technical Digest (Optical Society of America, 2013), paper OM2B.2. http://www.opticsinfobase.org/abstract.cfm?URI=OFC-2013-OM2B.2 [CrossRef]

*h*

_{0},

*P*and

_{sat}*L*(SOA loss) and fitted them to the average gain versus SOA input power curve. To extract the remaining two parameters,

*α*and

*τ*, we measured CE for four-wave mixing in SOAs as a function of frequency detuning. We compared the theoretical curve of CE versus frequency detuning with experimental results, and varied

_{c}*α*and

*τ*to find a good fit between the two curves [19

_{c}19. B. Filion, A. Ghazisaeidi, L. A. Rusch, and S. Larochelle, “Extraction of semiconductor optical amplifier parameters for wavelength conversion modeling,” in *Proceedings of IEEE Photonics Conference* (Institute of Electrical and Electronics Engineers, Arlington, 2011), pp. 367–368. [CrossRef]

## 3. Experimental setup

^{20}-1 pseudo-binary random sequences (PRBSs). These signals form the 16-QAM signal set that drives the I/Q (in-phase/quadrature) Mach-Zehnder external modulator (SHF 46213D). The SOA is used in a booster configuration at the transmitter to increase launched power. The 1-nm optical band-pass filter after the SOA has 3.8-dB loss, and limits ASE.

24. S. Zhang, C. Yu, P. Y. Kam, and J. Chen, “Parallel implementation of decision-aided maximum likelihood phase estimation in coherent M-ary phase-shifted keying systems,” IEEE Photon. Technol. Lett. **21**(19), 1471–1473 (2009). [CrossRef]

## 4. Experimental and numerical results

### 4.1 Appropriate SOA operating condition

*P*, for NL-SOA and L-SOA are presented in Figs. 3(a) and 3(b), respectively. We observe significant improvement (~6 dB) in launched power to the fiber when applying DFBP to mitigate nonlinearity for both SOAs. As expected, with higher bias currents, the SOA gives more gain which in turn leads to higher launched powers. The performance is, however, limited due to severe nonlinearity.

_{launched}*I*= 160 mA as compared to launched powers for

_{bias}*I*= 250 mA and 300 mA. Although BER less than a FEC limit of 3.8e-3 is achievable for all three examined bias currents, we choose

_{bias}*I*= 160 mA as a good working point for two reasons. First, the BER distance from the FEC limit is more reliable for this case and second, the SOA power consumption is less for lower bias currents. We show the gain versus bias current of the CIP nonlinear SOA as an inset to demonstrate that the obtained gain decreases quickly for currents below around 160 mA. Therefore,

_{bias}*I*= 160 mA is a good compromise between gain and performance. As shown in Fig. 3(b), the difference between launched power for

_{bias}*I*= 400 mA and 600 mA is 1 dB for the linear Covega SOA, as well. Therefore, we select

_{bias}*I*= 400 mA as operating point for the Covega SOA considering above the previously mentioned reasons, and especially to lower power consumption. Simulation results for the selected bias currents are shown with diamond makers for both SOAs in Fig. 3 verifying the experimental results for coarse parameter DFBP. As mentioned in section 2.3, forward propagation parameters for SOA in simulations are adjusted using the information from SOA characterizations.

_{bias}### 4.2 Coarse vs. fine parameter estimation

*h*

_{0}and

*α*either vary little among SOAs or have little impact on the DFBP improvement. The parameters

*P*and

_{sat}*τ*, however, vary over wide ranges and DFBP performance is sensitive to these values. For instance, we observed that for our SOAs,

_{c}*P*can vary from 6 to 14 dBm, while

_{sat}*τ*can vary from 45 to 285 ps. This large search area can be examined in a brute force manner with fine resolution (0.2 dB steps for

_{c}*P*and 5 ps steps for

_{sat}*τ*), or a reduced search area can be adopted to decrease the delay and computational overhead for parameter estimation. We examine experimentally the impact of using a coarse resolution (5 values for

_{c}*P*and 9 values for

_{sat}*τ*) for estimation.

_{c}*P*and

_{sat}*τ*(examining 45 pairs) that minimizes the EVM for those symbols. We then take the EVM optimized

_{c}*P*and

_{sat}*τ*and find the BER over the entire captured data set. In the second case, we take all captured data and minimize the BER by examining in turn a total of ~300 pairs of values for

_{c}*P*and

_{sat}*τ*. The same captured data is used in both cases. We repeated the procedure for each SOA type examined.

_{c}*P*and

_{sat}*τ*. We sweep these parameters with fine resolution (0.2 dB for

_{c}*P*and 5ps for

_{sat}*τ*), calculating the BER for each parameter pair. The search space is chosen to have BER contours fall in the region of the FEC limit. Figure 5(a) corresponds to the nonlinear NL-SOA, while Fig. 5(b) gives results for the linear L-SOA. The plots are reported for

_{c}*P*= −19 and −13 dBm for NL-SOA and L-SOA, respectively. The dark central section of the contour represents BER performance well below the FEC threshold. The points highlighted correspond to the EVM optimized parameters found.

_{in}*P*between 6 and 14 dBm, and

_{sat}*τ*between 45 and 285 ps. We can see that this parameter space clearly covers the BER range of interest– that above and below the FEC limit. Despite having covered a wide range with limited resolution, our approach fell safely in the below-FEC level. Even with no prior information on the SOA used (either SOA characterization or even linear/non-linear category), we can blindly find a DFBP solution that moves us below the FEC level. Figure 5 suggests that DFBP performance is more sensitive to

_{c}*P*than

_{sat}*τ*

_{c}. The width of the low-BER region for

*P*is around 1 dBm for both plots which validates our choice for resolution of

_{sat}*P*in coarse estimation.

_{sat}### 4.3 Propagation performance – two SOA types

*P*= −21 and −17 dBm (or equivalently,

_{in}*P*≈1 dBm) for NL-SOA and L-SOA, respectively. We launched the 16-QAM signal into 80 and 60 km of SSMF fiber for each SOA. The OSNR penalty is less than 4 dB for all cases when we apply the DFBP algorithm. While not shown in Fig. 6, we also observed that with 100 km of fiber, the BER is above the FEC limit within the achievable OSNR range.

_{launched}## 5. Conclusion

## References and links

1. | C. R. Doerr, “High performance photonic integrated circuits for coherent fiber communication,” in |

2. | G. Contestabile, Y. Yoshida, A. Maruta, and K. Kitayama, “100 nm-bandwidth positive-efficiency wavelength conversion for m-PSK and m-QAM signals in QD-SOA,” in |

3. | C. Porzi, A. Bogoni, and G. Contestabile, “Regeneration of DPSK signals in a saturated SOA,” IEEE Photon. Technol. Lett. |

4. | A. Ghazisaeidi, F. Vacondio, A. Bononi, and L. A. Rusch, “SOA intensity noise suppression: A Multicanonical Monte Carlo simulator of extremely low BER,” J. Lightwave Technol. |

5. | Z. Li, Y. Dong, J. Mo, Y. Wang, and C. Lu, “1050-kmWDM transmission of 8×10.709Gb/s DPSK signal using cascaded in-line semiconductor optical amplifiers,” IEEE Photon. Technol. Lett. |

6. | P. Cho, Y. Achiam, G. Levy-Yurista, M. Margalit, Y. Gross, and J. Khurgin, “Investigation of SOA nonlinearities on the amplification of DWDM channels with spectral efficiency up to 2.5 b/s/Hz,” IEEE Photon. Technol. Lett. |

7. | X. Wei, Y. Su, X. Liu, J. Leuthold, and S. Chandrasekhar, “10-Gb/s RZ-DPSK transmitter using a saturated SOA as a power booster and limiting amplifier,” IEEE Photon. Technol. Lett. |

8. | L. H. Spiekman, J. M. Wiesenfeld, A. H. Gnauck, L. D. Garrett, G. N. Van den Hoven, T. van Dongen, M. J. H. Sander-Jochem, and J. J. M. Binsma, “Transmission of 8 DWDM channels at 20 Gb/s over 160 km of standard fiber using a cascade of semiconductor optical amplifiers,” IEEE Photon. Technol. Lett. |

9. | D. Zimmerman and L. Spiekman, “Amplifiers for the masses: EDFA, EDWA, and SOA amplets for metro and access applications,” J. Lightwave Technol. |

10. | T. Yasui, Y. Shibata, K. Tsuzuki, N. Kikuchi, Y. Kawaguchi, M. Arai, and H. Yasaka, “Lossless 10-Gbit/s InP n-p-i-n Mach-Zehnder modulator monolithically integrated with semiconductor optical amplifier,” in |

11. | A. Nakanishi, N. Sasada, Y. Sakuma, R. Washino, K. Okamoto, H. Hayashi, H. Arimoto, and S. Tanaka, “Uncooled (0 to 85°C) and full C-band operation of a 10.7 Gbit/s InP Mach-Zehnder modulator monolithically integrated with SOA,” in |

12. | N. Kamitani, Y. Yoshida, and K. Kitayama, “Experimental study on impact of SOA nonlinear phase noise in 40Gbps coherent 16QAM transmissions,” in |

13. | A. Ghazisaeidi and L. A. Rusch, “On the efficiency of digital back-propagation for mitigating SOA-induced nonlinear impairments,” J. Lightwave Technol. |

14. | S. Amiralizadeh, A. T. Nguyen, C.-S. Park, A. Ghazisaeidi, and L. A. Rusch, “Experimental validation of digital filter back-propagation to suppress SOA-induced nonlinearities in 16-QAM,” in |

15. | F. Vacondio, A. Ghazisaeidi, A. Bononi, and L. A. Rusch, “Low-complexity compensation of SOA nonlinearity for single-channel PSK and OOK,” J. Lightwave Technol. |

16. | X. Li and G. Li, “Electrical postcompensation of SOA impairments for fiber-optic transmission,” IEEE Photon. Technol. Lett. |

17. | X. Li and G. Li, “Joint fiber and SOA compensation using digital backward propagation,” IEEE Photon. J. |

18. | S. Lange, Y. Yoshida, and K. Kitayama, “ A low-complexity digital pre-compensation of SOA induced phase distortion in coherent QAM transmissions,” in |

19. | B. Filion, A. Ghazisaeidi, L. A. Rusch, and S. Larochelle, “Extraction of semiconductor optical amplifier parameters for wavelength conversion modeling,” in |

20. | A. Saleh, “Nonlinear models of travelling-wave optical amplifiers,” Electron. Lett. |

21. | R. Schmogrow, B. Nebendahl, M. Winter, A. Josten, D. Hillerkuss, S. Koenig, J. Meyer, M. Dreschmann, M. Huebner, C. Koos, J. Becker, W. Freude, and J. Leuthold, “Error vector magnitude as a performance measure for advanced modulation formats,” IEEE Photon. Technol. Lett. |

22. | D. Cassioli, S. Scotti, and A. Mecozzi, “A time-domain computer simulator of the nonlinear response of semiconductor optical amplifiers,” IEEE J. Quantum Electron. |

23. | M. Selmi, Y. Jaouen, and P. Cibalt, “Accurate digital frequency estimator for coherent PolMux QAM transmission systems,” in European Conference and Exhibition on Optical Communication, Vienna, Austria, P3.08 (2009). |

24. | S. Zhang, C. Yu, P. Y. Kam, and J. Chen, “Parallel implementation of decision-aided maximum likelihood phase estimation in coherent M-ary phase-shifted keying systems,” IEEE Photon. Technol. Lett. |

**OCIS Codes**

(060.1660) Fiber optics and optical communications : Coherent communications

(060.4510) Fiber optics and optical communications : Optical communications

**ToC Category:**

Fiber Optics and Optical Communications

**History**

Original Manuscript: June 18, 2013

Revised Manuscript: July 26, 2013

Manuscript Accepted: August 15, 2013

Published: August 22, 2013

**Citation**

Siamak Amiralizadeh, An T. Nguyen, and Leslie A. Rusch, "Error vector magnitude based parameter estimation for digital filter back-propagation mitigating SOA distortions in 16-QAM," Opt. Express **21**, 20376-20386 (2013)

http://www.opticsinfobase.org/oe/abstract.cfm?URI=oe-21-17-20376

Sort: Year | Journal | Reset

### References

- C. R. Doerr, “High performance photonic integrated circuits for coherent fiber communication,” in Optical Fiber Communication Conference, OSA Technical Digest (Optical Society of America, 2010), paper OWU5. http://www.opticsinfobase.org/abstract.cfm?URI=OFC-2010-OWU5 [CrossRef]
- G. Contestabile, Y. Yoshida, A. Maruta, and K. Kitayama, “100 nm-bandwidth positive-efficiency wavelength conversion for m-PSK and m-QAM signals in QD-SOA,” in Optical Fiber Communication Conference, OSA Technical Digest (Optical Society of America, 2013), paper OTh1C.6. http://www.opticsinfobase.org/abstract.cfm?URI=OFC-2013-OTh1C.6 [CrossRef]
- C. Porzi, A. Bogoni, and G. Contestabile, “Regeneration of DPSK signals in a saturated SOA,” IEEE Photon. Technol. Lett.24(18), 1597–1599 (2012). [CrossRef]
- A. Ghazisaeidi, F. Vacondio, A. Bononi, and L. A. Rusch, “SOA intensity noise suppression: A Multicanonical Monte Carlo simulator of extremely low BER,” J. Lightwave Technol.27(14), 2667–2677 (2009). [CrossRef]
- Z. Li, Y. Dong, J. Mo, Y. Wang, and C. Lu, “1050-kmWDM transmission of 8×10.709Gb/s DPSK signal using cascaded in-line semiconductor optical amplifiers,” IEEE Photon. Technol. Lett.16(7), 1760–1762 (2004). [CrossRef]
- P. Cho, Y. Achiam, G. Levy-Yurista, M. Margalit, Y. Gross, and J. Khurgin, “Investigation of SOA nonlinearities on the amplification of DWDM channels with spectral efficiency up to 2.5 b/s/Hz,” IEEE Photon. Technol. Lett.16(3), 918–920 (2004). [CrossRef]
- X. Wei, Y. Su, X. Liu, J. Leuthold, and S. Chandrasekhar, “10-Gb/s RZ-DPSK transmitter using a saturated SOA as a power booster and limiting amplifier,” IEEE Photon. Technol. Lett.16(6), 1582–1584 (2004). [CrossRef]
- L. H. Spiekman, J. M. Wiesenfeld, A. H. Gnauck, L. D. Garrett, G. N. Van den Hoven, T. van Dongen, M. J. H. Sander-Jochem, and J. J. M. Binsma, “Transmission of 8 DWDM channels at 20 Gb/s over 160 km of standard fiber using a cascade of semiconductor optical amplifiers,” IEEE Photon. Technol. Lett.12(6), 717–719 (2000). [CrossRef]
- D. Zimmerman and L. Spiekman, “Amplifiers for the masses: EDFA, EDWA, and SOA amplets for metro and access applications,” J. Lightwave Technol.22(1), 63–70 (2004). [CrossRef]
- T. Yasui, Y. Shibata, K. Tsuzuki, N. Kikuchi, Y. Kawaguchi, M. Arai, and H. Yasaka, “Lossless 10-Gbit/s InP n-p-i-n Mach-Zehnder modulator monolithically integrated with semiconductor optical amplifier,” in Optical Fiber Communication Conference, OSA Technical Digest (Optical Society of America, 2008), paper OThC5. http://www.opticsinfobase.org/abstract.cfm?URI=OFC-2008-OThC5 [CrossRef]
- A. Nakanishi, N. Sasada, Y. Sakuma, R. Washino, K. Okamoto, H. Hayashi, H. Arimoto, and S. Tanaka, “Uncooled (0 to 85°C) and full C-band operation of a 10.7 Gbit/s InP Mach-Zehnder modulator monolithically integrated with SOA,” in Optical Fiber Communication Conference, OSA Technical Digest (Optical Society of America, 2013), paper OW1G.3. http://www.opticsinfobase.org/abstract.cfm?URI=OFC-2013-OW1G.3
- N. Kamitani, Y. Yoshida, and K. Kitayama, “Experimental study on impact of SOA nonlinear phase noise in 40Gbps coherent 16QAM transmissions,” in European Conference and Exhibition on Optical Communication, OSA Technical Digest (Optical Society of America, 2012), paper P1.04. http://www.opticsinfobase.org/abstract.cfm?URI=ECEOC-2012-P1.04 [CrossRef]
- A. Ghazisaeidi and L. A. Rusch, “On the efficiency of digital back-propagation for mitigating SOA-induced nonlinear impairments,” J. Lightwave Technol.29(21), 3331–3339 (2011). [CrossRef]
- S. Amiralizadeh, A. T. Nguyen, C.-S. Park, A. Ghazisaeidi, and L. A. Rusch, “Experimental validation of digital filter back-propagation to suppress SOA-induced nonlinearities in 16-QAM,” in Optical Fiber Communication Conference, OSA Technical Digest (Optical Society of America, 2013), paper OM2B.2. http://www.opticsinfobase.org/abstract.cfm?URI=OFC-2013-OM2B.2 [CrossRef]
- F. Vacondio, A. Ghazisaeidi, A. Bononi, and L. A. Rusch, “Low-complexity compensation of SOA nonlinearity for single-channel PSK and OOK,” J. Lightwave Technol.28(3), 277–288 (2010). [CrossRef]
- X. Li and G. Li, “Electrical postcompensation of SOA impairments for fiber-optic transmission,” IEEE Photon. Technol. Lett.21(9), 581–583 (2009). [CrossRef]
- X. Li and G. Li, “Joint fiber and SOA compensation using digital backward propagation,” IEEE Photon. J.2(5), 753–758 (2010). [CrossRef]
- S. Lange, Y. Yoshida, and K. Kitayama, “ A low-complexity digital pre-compensation of SOA induced phase distortion in coherent QAM transmissions,” in Optical Fiber Communication Conference, OSA Technical Digest (Optical Society of America, 2013), paper OTh3C.7. http://www.opticsinfobase.org/abstract.cfm?URI=OFC-2013-OTh3C.7
- B. Filion, A. Ghazisaeidi, L. A. Rusch, and S. Larochelle, “Extraction of semiconductor optical amplifier parameters for wavelength conversion modeling,” in Proceedings of IEEE Photonics Conference (Institute of Electrical and Electronics Engineers, Arlington, 2011), pp. 367–368. [CrossRef]
- A. Saleh, “Nonlinear models of travelling-wave optical amplifiers,” Electron. Lett.24(14), 835–837 (1988). [CrossRef]
- R. Schmogrow, B. Nebendahl, M. Winter, A. Josten, D. Hillerkuss, S. Koenig, J. Meyer, M. Dreschmann, M. Huebner, C. Koos, J. Becker, W. Freude, and J. Leuthold, “Error vector magnitude as a performance measure for advanced modulation formats,” IEEE Photon. Technol. Lett.24(1), 61–63 (2012). [CrossRef]
- D. Cassioli, S. Scotti, and A. Mecozzi, “A time-domain computer simulator of the nonlinear response of semiconductor optical amplifiers,” IEEE J. Quantum Electron.36(9), 1072–1080 (2000). [CrossRef]
- M. Selmi, Y. Jaouen, and P. Cibalt, “Accurate digital frequency estimator for coherent PolMux QAM transmission systems,” in European Conference and Exhibition on Optical Communication, Vienna, Austria, P3.08 (2009).
- S. Zhang, C. Yu, P. Y. Kam, and J. Chen, “Parallel implementation of decision-aided maximum likelihood phase estimation in coherent M-ary phase-shifted keying systems,” IEEE Photon. Technol. Lett.21(19), 1471–1473 (2009). [CrossRef]

## Cited By |
Alert me when this paper is cited |

OSA is able to provide readers links to articles that cite this paper by participating in CrossRef's Cited-By Linking service. CrossRef includes content from more than 3000 publishers and societies. In addition to listing OSA journal articles that cite this paper, citing articles from other participating publishers will also be listed.

« Previous Article | Next Article »

OSA is a member of CrossRef.