rdf-syntax-grammar
mods:
  schema location: http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
  title info:
    title: Comparison of direct sequence and multicarrier CDMA systems employing multiuser detectors
  name:
    name part: Deshpande, Yogen Nandkumar
    name part: 1977-
    role:
      role term: creator
  type of resource: text
  genre: bibliography
  origin info:
    place:
      place term: xx
    date issued: 2002
    issuance: monographic
  language:
    language term: eng
  physical description:
    form: print
    form: remote
    extent: viii, 60 leaves : illustrations ; 28 cm.
  abstract: In CDMA, users in a given cell transmit simultaneously in the same frequency band. Two ways to spread the spectra of users' signals have been considered in this work. In the first technique, called Direct Sequence (DS) CDMA, each user transmits a digital data bit by transmitting a sequence of digital symbols of much smaller duration, called chips, one after the other on a given carrier frequency. The sequence of chips (spreading sequence) is unique for each user and is used to distinguish between the users. The second technique, called multicarrier CDMA uses as many carrier frequencies as the number of chips per bit. Each bit is transmitted by transmitting corresponding chips simultaneously on different carrier frequencies. In this case, the chip duration is equal to the bit duration. In this work, computer simulations are used to observe the performance of these two modulation techniques for two multiuser detectors viz. a Parallel Interference Canceller (PIC) and a decorrelator. The channel considered is a frequency selective slow Rayleigh fading channel. Thus, there are multiple resolvable paths through which the signal is received at the receiver. It has been observed that both the receivers employed in a multicarrier system significantly outperform their counterparts in a DS system. It is shown that the multicarrier system is comparatively much more resistant to self interference due to multipath. Its superior performance is attributed to this resistance. It is suggested that for a DS system, choice of spreading codes that have good autocorrelation properties can alleviate this problem up to some extent. However, it still cannot outperform a multicarrier system. Hence, use of multicarrier modulation is advocated.
  note: by Yogen Nandkumar Deshpande.
  note: "Major subject: Electrical Engineering".
  note: Vita.
  note: Also available online.
  note: Issued also on microfiche from Lange Micrographics.
  note: M.S. Texas A&M University 2002
  note: Includes bibliographical references (leaves 56-59).
  subject:
    topic: Major electrical engineering
  identifier: https://hdl.handle.net/1969.1/ETD-TAMU-2002-THESIS-D47
  related item:
    location:
      url: https://hdl.handle.net/1969.1/ETD-TAMU-2002-THESIS-D47
  record info:
    record content source: TXA
    record creation date: 021210
    record change date: 20220103134509.0
    record identifier: in00001716809