Semi-hard interference cancellation for uncoded DS-CDMA systems

C Kasparis, RJ Piechocki, AR Nix, PN Fletcher

Research output: Chapter in Book/Report/Conference proceedingConference Contribution (Conference Proceeding)

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A new iterative technique for suppressing multiuser interference in uncoded DS-CDMA systems is proposed. In the new approach semi-hard decisions are taken at the output of the linear MMSE detector. This involves taking hard decisions only for symbols which satisfy a reliability criterion, while the rest are left unaltered in their soft form. The semi-hard estimate is subsequently used for parallel interference cancellation, which is then followed by additional linear MMSE filtering. This procedure is repeated a small number of times. Simulation results show that the proposed detector is capable of approaching closely the single-user performance in a fully loaded multiuser scenario and this is achieved within 5 to 10 iterations. In the same system scenario the new technique outperforms the probabilistic data association (PDA) algorithm, which is considered as a state-of-the art solution. The computational complexity of the proposed detector is of the same order as of a standard linear detector.
Translated title of the contributionSemi-hard interference cancellation for uncoded DS-CDMA systems
Original languageEnglish
Title of host publicationVehicular Technology Conference 2004 (VTC 2004-Fall)
PublisherInstitute of Electrical and Electronics Engineers (IEEE)
Pages3708 - 3712
Number of pages5
ISBN (Print)10903038
Publication statusPublished - Sept 2004
Event60th Vehicular Technology Conference 2004 (VTC 2004-Fall) - Los Angeles, United States
Duration: 28 Sept 200429 Sept 2004


Conference60th Vehicular Technology Conference 2004 (VTC 2004-Fall)
Country/TerritoryUnited States
CityLos Angeles

Bibliographical note

Conference Proceedings/Title of Journal: IEEE 60th Vehicular Technology Conference, 2004 (VTC 2004-Fall)
Rose publication type: Conference contribution

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  • code division multiple access
  • interference suppression


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