| 261. |
- Kylemark, Per, 1976, et al.
(författare)
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Impact of Pump Phase-Modulation on the Bit-Error Rate in Fiber-Optical Parametric-Amplifier-Based Systems
- 2007
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Ingår i: IEEE Photonics Technology Letters. - 1041-1135 .- 1941-0174. ; 19:2, s. 79-81
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Tidskriftsartikel (refereegranskat)abstract
- Pump phase-modulation is often needed to suppress stimulated Brillouin scattering in fiber-optical parametric amplifiers. We show that while this causes a gain variation with a corresponding Q-value penalty, the actual bit-error-rate degradation is not always significant. The findings are supported by experimental studies.
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| 262. |
- Kylemark, Per, 1976, et al.
(författare)
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Noise in dual-pumped fiber-optical parametric amplifiers: Theory and experiments
- 2007
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Ingår i: Journal of Lightwave Technology. - : Institute of Electrical and Electronics Engineers (IEEE). - 0733-8724 .- 1558-2213. ; 25:9, s. 2837-2846
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Tidskriftsartikel (refereegranskat)abstract
- The noise figure (NF) of a dual-pumped parametric amplifier with copolarized pumps is quantified for the first time to our knowledge. It is shown that the NF is increased by the noise on the pump sources, in agreement with theory, and that it gives a uniform NF degradation due to a uniform gain spectrum. The magnitude of the NF degradation increases with increasing input-signal power. Various aspects of the NF are studied, such as the effects of three idlers generated by the four-sideband interaction, and Raman-induced losses and excess noise caused by the population of thermal phonons. It is shown that the use of unequal pump powers only affects the low-power NIT to a minimal degree. Also, the gain dependence of the NF is studied, as are the wavelength and signal power dependences of the NE It is shown that at high gain, the NF saturates even when pump noise is an issue. Also, unequal pump powers with fixed gain have a minor impact on the noise performance of the amplifier. Theory and experiments agree well with each other.
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| 263. |
- Kylemark, Per, 1976, et al.
(författare)
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Noise in Orthogonally Pumped Fiber-Optical Parametric Amplifiers
- 2007
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Ingår i: IEEE Photonics Technology Letters. - 1041-1135 .- 1941-0174. ; 19:2, s. 88-90
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Tidskriftsartikel (refereegranskat)abstract
- The noise figure (NF) of a fiber-optical parametric amplifier, driven by pumps with orthogonal polarizations, is quantified experimentally. It is shown that this amplifier has a signal- polarization -dependent gain, with a corresponding polarization-dependent NF. The polarization dependence of the NF is particularly large when higher input-signal powers are amplified, in which case pump-induced noise dominates. At lower input-signal powers, the NF is less dependent on the input polarization, but increases closer to the lower-frequency pump.
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| 264. |
- Kylemark, Per, 1976, et al.
(författare)
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Noise statistics in fiber optical parametric amplifiers
- 2007
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Ingår i: Journal of Lightwave Technology. - : Institute of Electrical and Electronics Engineers (IEEE). - 0733-8724 .- 1558-2213. ; 25:2, s. 612-620
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Tidskriftsartikel (refereegranskat)abstract
- In this paper, we show both theoretically and experimentally that the probability density function of the intensity of an amplified signal by parametric amplifiers subject to a pump with excess noise is highly asymmetric. This is due to the nonlinear relationship between the optical pump power and the parametric gain. Because of this, the relationship between the noise figure (NF) and the bit error rate (BER) is modified, compared with that predicted by the chi(2) theory, which is an effect that is notable at large NFs and low BERs. The difference in predicted BER can be of several orders of magnitudes between the correct theory and the chi(2) approximation in single-stage parametric amplifiers. We also show that in the limit of many cascaded parametric amplifiers, the statistics of the noise of an amplified optical signal approaches chi(2). Furthermore, the BER of a parametric amplifier is generally lower compared with erbium-doped fiber amplifiers for the same NF values if we assume quantum-limited amplification.
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| 265. |
- Kylemark, Per, 1976, et al.
(författare)
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Noise statistics of fiber optical parametric amplifiers
- 2006
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Ingår i: OFC/NFOEC 2006. 2006 Optical Fiber Communication Conference and National Fiber Optic Engineers Conference. ; , s. OWT5-
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Konferensbidrag (refereegranskat)abstract
- We show both theoretically and experimentally that the probability density function of a signal amplified by parametric amplifiers with pump excess noise is non-Gaussian and asymmetric. This impacts the relationship between the noise figure and the bit-error rate
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| 266. |
- Kylemark, Per, 1976, et al.
(författare)
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Penalties due to the combined effects of amplitude noise and timing-jitter with application to a 40 Gbit/s DM-soliton system
- 2005
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Ingår i: Optical Fiber Technology. ; 11:1, s. 20-33
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Tidskriftsartikel (refereegranskat)abstract
- We derive equations for penalties introduced by the combined effects of timing-jitter and amplitude noise in a transmission link. We then apply the results on a DM-soliton system operating at 40 Gbit/s, where Gordon-Haus-jitter is important at large distances. We predict, using the theory, the maximum transmission distance for various systems. Finally, we compare the theory with numerical simulations and find a good agreement between them.
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| 267. |
- Kylemark, Per, 1976, et al.
(författare)
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Properties of pump-induced noise in fiber optic parametric amplifiers
- 2006
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Ingår i: Optics InfoBase Conference Papers. - Washington, D.C. : OSA. - 2162-2701.
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Konferensbidrag (refereegranskat)abstract
- We investigate the pump-induced noise in fiberoptic parametric amplifiers theoretically and experimentally, and find unique features with respect to wavelength dependence and noise statistics.
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| 268. |
- Kylemark, Per, 1976, et al.
(författare)
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Semi-analytic saturation theory of fiber optical parametric amplifiers
- 2006
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Ingår i: Journal of Lightwave Technology. ; 24:9, s. 3471-9
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Tidskriftsartikel (refereegranskat)abstract
- A semi-analytical theory for the gain saturation of parametric amplifiers is presented. The theory is both simple and intuitive, it is compared with experiments on a parametric amplifier, and a very good agreement is found. Furthermore, using theoretical results, a method to obtain saturation characteristics for parametric amplifiers that have features not easily reproduced by theory is presented. The obtained method finds saturation characteristics in a few steps, providing that the gain studied is above 15 dB, where the approximations upon which our simple expression is based are strictly valid. An exact solution of the gain saturation when the pump power is totally converted is also presented and compared with the simplified expression using previously obtained theoretical results
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| 269. |
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| 270. |
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