Sökning: "code-division multiple-access CDMA"

Visar resultat 21 - 25 av 32 avhandlingar innehållade orden code-division multiple-access CDMA.

  1. 21. Coding, Modulation and Multiuser Decoding for DS-CDMA Systems

    Författare :Tony Ottosson Gadd; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Sammanfattning : The general trend both in wireless and fixed network communication systems is flexibility in services, data rates, desired delay and performance. Future systems should not be designed for specific services but be more general and allow for a multitude of services, both now existing and those not yet invented. LÄS MER

  3. 22. Iterative Detection, Decoding and Channel Parameter Estimation for Orthogonally Modulated DS-CDMA Systems

    Författare :Pei Xiao; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Sammanfattning : In this thesis, we study iterative detection, decoding and channel parameter estimation algorithms for asynchronous direct-sequence code division multiple access (DS-CDMA) systems employing orthogonal signalling formats and long scrambling codes. Multiuser detection techniques are widely used to combat the detrimental effects of multipath fading and multiple access interference (MAI), which are the major impairments in CDMA communication systems. LÄS MER

  4. 23. Subspace-Based Parameter Estimation Problems in Signal Processing

    Författare :Joakim Sorelius; Torsten Söderström; Peter Stoica; Uppsala universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; sensor array processing; parameter estimation; spread spectrum communication; direct sequence CDMA; order estimation; subspace fitting; blind identification; system identification; Signal Processing; Signalbehandling;

    Sammanfattning : The effects of multipath-induced angular spread and non-zero band-width on narrow-band direction-of-arrival (DOA) estimation are investigated. In both cases expressions for the resulting estimation error are developed for the MUSIC, ESPRIT and WSF DOA estimators. LÄS MER

  5. 24. Multiuser Serially Concatenated Continuous Phase Modulation

    Författare :Pär Moqvist; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : 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. LÄS MER

  7. 25. Digital communication in wireline and wireless environments

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

    Sammanfattning : This thesis consists of an introduction and five parts dealing with digital communication. Three parts address Discrete Multi-Tone modulation (DMT), a wireline form of Orthogonal Frequency Division Multiplexing (OFDM). LÄS MER