Wireless Personal Communications

, Volume 55, Issue 2, pp 273–288 | Cite as

New Signature Waveforms for Multi-rate QS-CDMA System with QPSK Modulation

  • Lifang FengEmail author
  • Pingzhi Fan
  • Kok-Keong Loo
  • Li Hao


This paper presents a multi-rate quasi-synchronous CDMA (QS-CDMA) system with QPSK modulation based on the new signature waveforms, namely GPZ-chip waveforms which are constructed by the generalized pairwise Z-complementary (GPZ) codes and optimal chip waveforms. According to the properties of GPZ-chip waveforms, the multiple access interference of different users can be reduced or eliminated. The interferences among different streams of the same user are handled by an optimal (or suboptimal) multi-stream detector(s). The performance of the proposed system is simulated and analyzed in a cellular communication environment consisting of multipath fading. The result shows that the proposed system has similar performance as compared to the single-rate QS-CDMA system employing GPZ codes with one chip waveform due to the properties of multi-stream detection. Also, the proposed system can achieve a significant interference reduction as compared to the multi-rate system employing concatenated WH/m sequence sets with one chip waveform due to the zero correlation zone properties of the GPZ-chip waveforms, thus resulting better BER performance.


Zero correlation zone GPZ codes Signature waveforms Quasi-synchronous CDMA system 


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Copyright information

© Springer Science+Business Media, LLC. 2009

Authors and Affiliations

  • Lifang Feng
    • 1
    Email author
  • Pingzhi Fan
    • 2
  • Kok-Keong Loo
    • 3
  • Li Hao
    • 2
  1. 1.School of Information EngineeringUniversity of Science and Technology BeijingBeijingChina
  2. 2.Provincial Key Lab of Information Coding and Transmission, Institute of Mobile CommunicationsSouthwest Jiaotong UniversityChengduChina
  3. 3.School of Engineering and DesignBrunel UniversityLondonUK

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