Search for dissertations about: "phase modulation"

Showing result 16 - 20 of 255 swedish dissertations containing the words phase modulation.

  2. 16. Multidimensional Modulation Formats for Coherent Optical Communication Systems

    Author : Tobias Eriksson; Chalmers tekniska högskola; []
    Keywords : 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 ;

    Abstract : 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. READ MORE

  4. 17. Multi-level modulation formats for high-speed optical transmission systems

    Author : Ekawit Tipsuwannakul; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; quadrature amplitude modulation; spectral efficiency; differential detection; modulation format; coherent detection; phase shift keying;

    Abstract : Over the past several years, the use of multi-level modulation formats has enabledsignificant improvements in the field of optical fiber communication, particularlyin terms of per-channel bit-rate (i.e., line-rate) and spectral efficiency (SE), byencoding multiple bits per symbol. READ MORE

  5. 18. Some concatenated and iterative decoding approaches for continuous phase modulation

    Author : Ming Xiao; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; serially concatenated codes; Continuous phase modulation;

    Abstract : Several concatenated and iterative decoding approaches are used toimprove the power efficiency of continuous phase modulation (CPM).First a symbol interleaver is used for serially concatenated CPM(SCCPM). Convergence of iterative decoding for this scheme can beearlier (lower SNR: Signal-to-Noise-Ratio) compared to bitinterleaved SCCPM. READ MORE

  6. 19. Multiuser Serially Concatenated Continuous Phase Modulation

    Author : Pär Moqvist; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES;

    Abstract : A multiuser communication system using serially concatenated and randomly interleaved continuous phase modulation (SCCPM) over the additive white Gaussian noise (AWGN) channel is investigated. The users, which may be asynchronous, are allowed to have individual energy levels as well as carrier frequencies and phases. READ MORE

  7. 20. Modulation of Modular Multilevel Converters for HVDC Transmission

    Author : Arman Hassanpoor; Hans-Peter Nee; Staffan Norrga; Rainer Marquardt; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; HVDC; switching schemes; modulation; high power converters; power grids; Electrical Engineering; Elektro- och systemteknik;

    Abstract : The outstanding features of modular multilevel converters (MMC) have recently gained much attention in the high-voltage direct-current (HVDC) transmission field. Power quality, converter cost and system performance are three crucial aspects of HVDC MMCs which are directly linked to the converter modulation and switching schemes. READ MORE