Code orthogonality for wideband CDMA systems with multiple transmit antennas

MR Hunukumbure, BH Allen, MA Beach

Research output: Contribution to journalArticle (Academic Journal)peer-review

2 Citations (Scopus)
385 Downloads (Pure)


Code orthogonality is a useful indicator in determining the performance of the synchronous downlink of third generation Universal Mobile Telecommunication System (UMTS) Terrestrial Radio Access systems. In this paper, previous work on quantifying code orthogonality for single-antenna [or single-input single-output (SISO)] links is extended to fixed beamforming and transmit diversity schemes. Code orthogonality estimates from real measured channel data are extracted for typical outdoor radio environments. The results indicate that the spatial conditioning of fixed beamforming radio channels generally improves code orthogonality. In contrast, full code-rate transmit diversity schemes degrade code orthogonality.
Translated title of the contributionCode orthogonality for wideband CDMA systems with multiple transmit antennas
Original languageEnglish
Pages (from-to)3749 - 3756
Number of pages8
JournalIEEE Transactions on Vehicular Technology
Issue number6, part 2
Publication statusPublished - Nov 2007

Bibliographical note

Publisher: Institute of Electrical and Electronics Engineers, Inc. (IEEE)
Rose publication type: Journal article

Sponsorship: This work was supported in part by the Higher Education Funding Council for England Joint Research Equipment Initiative
1998 and in part by OFCOM’s U.K. Spectrum Efficiency Scheme. The work of M. Hunukumbure was supported by the ORS scheme and the University of Bristol scholarship during his postgraduate studentship.

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  • code orthogonality
  • fixed beamforming
  • transmit diversity
  • space- time block codes (STBC)
  • wideband code division multiple access (WCDMA)


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