Search for dissertations about: "Modulation based thesis"

Showing result 1 - 5 of 560 swedish dissertations containing the words Modulation based thesis.

  2. 1. Multicarrier modulation : duplexing design and interference/distortion mitigation

    Author : Rickard Nilsson; Luleå tekniska universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Signalbehandling; Signal Processing;

    Abstract : Aspects of modern communication systems is the overall theme of this thesis with emphasis placed on multicarrier modulation. The work considers four facets of such systems; namely duplexing design, interference mitigation, channel estimation and multiuser detection. READ MORE

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

    Author : Tobias Eriksson; Chalmers tekniska högskola; []
    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

  5. 3. Laser-based absorption spectrometry : development of NICE-OHMS towards ultra-sensitive trace species detection

    Author : Florian Schmidt; Ove Axner; Livio Gianfrani; Umeå universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; absorption spectrometry; trace species detection; fiber laser; modulation; cavity-enhanced spectroscopy; optical saturation; laser frequency stabilization; free-spectral-range; Physics; Fysik;

    Abstract : Laser-based absorption spectroscopy (AS) is a powerful technique for qualitative and quantitative studies of atoms and molecules. An important field of use of AS is the detection of species in trace concentrations, which has applications not only in physics and chemistry but also in biology and medicine, encompassing environmental monitoring, regulation of industrial processes and breath analysis. READ MORE

  6. 4. Faraday modulation spectroscopy : Theoretical description and experimental realization for detection of nitric oxide

    Author : Jonas Westberg; Ove Axner; Gerard Wysocki; Umeå universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Faraday modulation spectroscopy FAMOS ; Westberg-Wang-Axner WWA method; Fourier coefficients; Lineshape asymmetries; Nitric oxide NO ; fysik; Physics;

    Abstract : Faraday modulation spectroscopy (FAMOS) is a laser-based spectroscopic dispersion technique for detection of paramagnetic molecules in gas phase. This thesis presents both a new theoretical description of FAMOS and experimental results from the ultra-violet (UV) as well as the mid-infrared (MIR) regions. READ MORE

  7. 5. Fibre-Optic Displacement and Temperature Sensing Using Coupling Based Intensity Modulation and Polarisation Modulation Techniques

    Author : Johan Jason; Hans-Erik Nilsson; Bertil Arvidsson; Werner Daum; Mittuniversitetet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; optical fibre sensor; displacement measurement; temperature measurement; fibre coupling; intensity modulation; birefringence; polarisation; OTDR; side-hole fibre;

    Abstract : Optical fibre sensors are employed in the measurements of a number of different physical properties or for event detection in safety and security systems. In those environments which suffer from electromagnetic disturbance, in harsh environments where electronics cannot survive and in applications in favour of distributed detection, fibre-optic sensors have found natural areas of use. READ MORE