Search for dissertations about: "phase modulation"

Showing result 1 - 5 of 188 swedish dissertations containing the words phase modulation.

  1. 1. Phase Modulation Techniques for On-Off Keying in Optical Fibre Transmission

    Author : Marco Forzati; [2007]
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; return-to-zero; fibre optics communication; phase modulation; nonlinear optics; dispersion management; high-speed optical transmission; modulation formats; fibres;

    Abstract : Increasing the channel bit rate is an efficient way to upgrade traffic capacity in installed transmission links. At bit rates of the order of 40 Gb/s, on-off keying (OOK) transmission becomes severely impaired by non-linear effects especially Intra-channel Four-Wave Mixing (IFWM) which limit the power at which the signal can be transmitted, and ultimately the transmission distance. READ MORE

  2. 2. Phase Noise Tolerant Modulation Formats and DSP Algorithms for Coherent Optical Systems

    University dissertation from Stockholm, Sweden : KTH Royal Institute of Technology

    Author : Jaime Rodrigo Navarro; KTH.; [2017]
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; optical communications; carrier phase recovery; blind phase search; circular quadrature amplitude modulation; CmQAM; coherent optical communications; digital signal processing; carrier phase estimation; equalization enhanced phase noise; EEPN; Telecommunication; Telekommunikation;

    Abstract : Coherent detection together with multilevel modulation formats has the potential to significantly increase the capacity of existing optical communication systems at no extra cost in signal bandwidth. However, these modulation formats are more susceptible to the impact of different noise sources and distortions as the distance between its constellation points in the complex plane reduces with the modulation index. READ MORE

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

    University dissertation from Stockholm, Sweden : KTH Royal Institute of Technology

    Author : Tobias Eriksson; [2015]
    Keywords : 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;

    Abstract : 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. READ MORE

  4. 4. Multi-Level Lossless Phase Modulation in Liquid Crystals for High-Speed Spatial Light Modulators

    University dissertation from Stockholm, Sweden : KTH Royal Institute of Technology

    Author : David Engström; [2006]
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; phase measurements; polarization; phase modulation; beam steering; Spatial light modulators; diffractive optics; ferroelectric liquid crystals;

    Abstract : The spatial light modulator (SLM) is a compact device that enables highly precise control of light propagation with low drive voltages and no moving parts. By imposing a certain phase modulation onto the incident lightwave, functions such as multi-beam steering, beam shaping, and air turbulence corrections can be achieved in realtime. READ MORE

  5. 5. The alternate-phase return-to-zero modulation format in high-speed optical-fibre communications

    University dissertation from Stockholm, Sweden : KTH Royal Institute of Technology

    Author : Marco Forzati; [2006]
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; high-speed optical transmission; return-to-zero; nonlinear optics; dispersion management; phase modulation; modulation formats; Fibre optics communication; fibres;

    Abstract : Increasing the channel bit rate is an efficient way to upgrade traffic capacity in installed transmission links. At bit rates of the order of 40 Gb/s, on-off keying transmission becomes severely impaired by non-linear effects,particularly Intra-channel Cross-Phase Modulation (IXPM) and Intra-channel Four-Wave Mixing (IFWM), which cause pulses in different bit slots to interact with each-other. READ MORE