Title :
Decision-Feedback Closest Lattice Point Search for UMTS HSPA System
Author :
Shim, Byonghyo ; Abrishamkar, Farrokh ; Kang, Insung
Author_Institution :
Sch. of Inf. & Commun., Korea Univ., Seoul, South Korea
Abstract :
This letter considers a low-complexity multiuser detection based on the closest lattice point search (CLPS) for high speed packet access (HSPA) system. Instead of attempting to solve the ML detection problem in the presence of intersymbol and inter-cell interference, we utilize interference cancelled chips obtained from a bidirectional decision feedback operation to detect symbols. As a result, the worst case complexity of the CLPS is bounded to a controllable level irrespective of multipath spans. From the simulation on single and multi cell downlink communications in HSPA systems, we show that the proposed method offers substantial performance gain over conventional RAKE and MMSE equalizer.
Keywords :
3G mobile communication; feedback; intersymbol interference; maximum likelihood detection; multiuser detection; packet radio networks; ML detection; UMTS HSPA system; bidirectional decision feedback operation; closest lattice point search; decision-feedback closest lattice point search; high speed packet access system; intercell interference; interference cancellation; intersymbol interference; low-complexity multiuser detection; maximum likelihood detection; multicell downlink communications; Closest lattice point search; high speed packet access; interference cancellation; multiuser detection; sphere decoding;
Journal_Title :
Signal Processing Letters, IEEE
DOI :
10.1109/LSP.2009.2028949
