A half-chip offset QPSK modulation CDMA scheme employing differential detection for advanced wireless LAN systems

Takatoshi Sugiyama, Masato Mizoguchi, Shuji Kubota

Research output: Contribution to journalArticle


SUMMARY This paper proposes a half-chip offset QPSK (Quadrature Phase Shift Keying) modulation CDMA (Code Division Multiple Access) scheme to allow the simple differential detection while realizing a compact spectrum in nonlinear channels for wireless LAN systems. The experimental results show the proposed scheme achieves excellent Pe (probability of error) performances in ACI (adjacent channel interference) and CCI (co-channel interference) environments. Moreover, by employing time diversity and high-coding-gain FEC (Forward Error Correction), the half-chip offset QPSK-CDMA scheme realizes an improvement of 3.0 dB (in terms of Eb/No at a Pe of 10-5) in Rician fading environments with a Doppler frequency fD of 10 Hz and a delay spread of 40 nsec.

Original languageEnglish
Pages (from-to)693-700
Number of pages8
JournalIEICE Transactions on Communications
Issue number5
Publication statusPublished - 1996 Jan 1



  • Differential detection
  • Forward error correction
  • Frequency utilization efficiency
  • Nonlinear channel
  • Offset qpsk-cdma
  • Time diversity

ASJC Scopus subject areas

  • Software
  • Computer Networks and Communications
  • Electrical and Electronic Engineering

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