Sökning: "optical modulation"

Visar resultat 1 - 5 av 200 avhandlingar innehållade orden optical modulation.

  1. 1. Generation and Applications of Picosecond Pulses in High-Capacity Fiber Optic Systems

    Författare :Jie Li; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; nonlinear distortion; optical pulse shaping; dispersion-management; eye-diagram; cross-phase modulation; optical sampling; optical fiber applications; multiplexing; parametric amplification; demultiplexing; optical pulses; fiber optical communication; nonlinear systems; time division multiplexing; four-wave mixing; polarization-mode dispersion; optical signal processing; fiber optical nonlinearities; fiber ring laser; soliton robustness; mode-locking; optical filters; networks;

    Sammanfattning : This thesis deals with short optical pulse generation from actively mode-locked Erbium-doped fiber ring lasers (ML-EFRL) and their applications in all-optical signal processing (optical sampling and switching) and transmission experiments for high-capacity fiber optic systems. In future ultra-high bit-rate optical time division multiplexed (OTDM) systems, one of the key requirements is to develop reliable optical pulse sources that can generate high quality optical pulses. LÄS MER

  3. 2. Nonlinear Propagation of Optical Pulses and Beams

    Författare :Magnus Karlsson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; self-phase modulation; optical wave breaking; paraxial-ray approximation; stimulated Raman scattering; nonlinear Schrödinger equation; optical collapse; modulational instability; higher-order dispersion; optical fibers; saturable nonlinearity; Kerr-nonlinearity; self-trapping; group-velocity dispersion; optical solitons; self-focusing;

    Sammanfattning : The propagation of optical beams and pulses under the influence of nonlinear effects is characterized by a rich variety of phenomena and many potentially important applications. We analyse two main topics in this context: nonlinear beam propagation, and nonlinear pulse propagation in optical fibers. LÄS MER

  4. 3. Multidimensional Modulation Formats for Coherent Single- and Multi-Core Fiber-Optical Communication Systems

    Författare :Tobias Eriksson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; four-dimensional 4D estimates of mutual information MI ; multidimensional modulation formats; lattice based modulation; biorthogonal modulation in eight dimensions; power efficiency; 16-ary quadrature amplitude modulation 16QAM ; quadrature phase shift keying QPSK ; polarization-switched QPSK PS-QPSK ; 128-ary set-partitioning 16QAM 128-SP-16QAM ; spectral efficiency; single parity check-coded modulation; multidimensional position modulation; achievable information rate.; iber-optical communication; multicore fiber transmission; binary pulse position modulation QPSK 2PPM-QPSK ; crosstalk;

    Sammanfattning : This thesis covers multidimensional modulation formats for coherent optical communication systems including spatial division multiplexed systems using multicore fibers. The single-mode optical signal has four dimensions which are spanned by the two orthogonal polarizations and the in-phase and quadrature components. LÄS MER

  5. 4. Multidimensional Modulation Formats for Coherent Optical Communication Systems

    Författare :Tobias Eriksson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; binary pulse position modulation QPSK; Fiber-optical communication; spectral efficiency; power efficiency; multidimensional position modulation.; 16-ary quadrature amplitude modulation 16QAM ; quadrature phase shift keying QPSK ; coherent detection; polarization-switched quadrature phase shift keying PS-QPSK ; 128-level set-partitioning QAM 128-SP-QAM ;

    Sammanfattning : Coherent optical receivers have enabled the use of multilevel modulation formats with high spectral efficiencies and long transmission reaches. Traditionally, modulation formats utilizing the two dimensions spanned by the amplitude and the phase of the signal have been dominating. LÄS MER

  7. 5. Modulation Optimization for Noncoherent Optical Systems

    Författare :Johnny Karout; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Direct detection; noncoherent communications; lattice codes; mutual information; fiber-optical communications; intensity modula- tion; sphere packing.; infrared communications; free-space optical communications;

    Sammanfattning : There has been a significant improvement in high-speed electronics and optical components over the past few years, and this is one of the key enabling factors for high data rate transmission. Moreover, multi- level modulation formats, which encode information onto the carrier’s amplitude and phase, are necessary to increase the spectral efficiency of communication systems. LÄS MER