19 research outputs found
Analytic theory of fiber-optic Raman polarizers
The Raman polarizer is a Raman amplifier which not only amplifies but also re-polarizes light. We propose a relatively simple and analytically tractable model - the ideal Raman polarizer, for describing the operation of this device. The model efficiently determines key device parameters such as the degree of polarization, the alignment parameter, the gain and the RIN variance
Theory of fiber optic co- and counter-pumped Raman polarizers
4openopenWabnitz, S.; Kozlov, V.; Nuno, J.; Ania-castanon, J. D.Wabnitz, Stefan; Kozlov, Victor; Nuno, J.; Ania castanon, J. D
Arbitrary real-time three-dimensional corporal object sensing and reconstruction scheme
A real-time three-dimensional (3D) object sensing and reconstruction scheme is presented that can be applied on any arbitrary corporeal shape. Operation is demonstrated on several calibrated objects. The system uses curvature sensors based upon in-line fiber Bragg gratings encapsulated in a low-temperature curing synthetic silicone. New methods to quantitatively evaluate the performance of a 3D object-sensing scheme are developed and appraised. It is shown that the sensing scheme yields a volumetric error of 1% to 9%, depending on the object
Unrepeatered 240-km 64-QAM transmission using distributed raman amplification over SMF fiber
We present a theoretical and experimental investigation of unrepeatered transmission over standard single-mode fiber (SMF-28) using several schemes of distributed Raman amplification, including first, second, and dual order. In order to further extend the transmission distance, we utilize advanced bidirectional higher-order ultra-long Raman fiber laser-based amplification, where we use fiber Bragg gratings (FBGs) to reflect Stokes-shifted light from the secondary pumps. Our work demonstrates the possibility of transmission up to 240-km span length with a total span loss of 52.7 dB. Here, we use a 28-Gbaud signal using a 64-quadrature amplitude modulation (QAM) modulation format. Our results highlight the contribution of nonlinear compensation using digital back propagation in a digital signal processor (DSP) code at the receiver
Theory of Fiber Optic Raman Polarizers
We propose and apply a theoretical description of a Raman amplifier based on the vector model of randomly
birefringent fibers to the characterization of Raman polarizers. The Raman polarizer is a special type of Raman
amplifier with the property of producing a highly repolarized beam when fed by relatively weak and unpolarized
light
Theory of fiber optic Raman polarizers
We propose and apply a theoretical description of a Raman amplifier based on the vector model of randomly birefringent fibers to the characterization of Raman polarizers. The Raman polarizer is a special type of Raman amplifier with the property of producing a highly repolarized beam when fed by relatively weak and unpolarized light
Multi-Channel raman polarizer with suppressed relative intensity noise for WDM transmission lines
We propose a method of suppressing the relative intensity noise caused by polarization-dependent gain that is inherent to Raman polarizers (RPs). This method involves bit-synchronously scrambling the state of polarization of a pulse (bit) before the pulse enters the RP. The proposed solution works for RPs operating in a depleted regime and is compatible with multichannel configurations
Multi-Channel Raman Polarizer with Suppressed Relative Intensity Noise for WDM Transmission Lines
We propose a method of suppressing the relative intensity noise caused by polarization-dependent gain that is inherent to Raman polarizers (RPs). This method involves bit-synchronously scrambling the state of polarization of a pulse (bit) before the pulse enters the RP. The proposed solution works for RPs operating in a depleted regime and is compatible with multichannel configurations
Performance improvement of broadband distributed Raman amplifier using bidirectional pumping with first and dual order forward pumps
In this paper, a new bidirectional pumping scheme with dual order forward pumps is proposed. Performance is compared numerically with conventional bidirectional and backward only pumping schemes for a 70 nm bandwidth, 61.5 km distributed Raman amplifier. We demonstrate that it is possible to design a flat gain spectrum with improved noise figure and OSNR, as well as a low gain ripple (< 1 dB)