Title :
SOVA equalization for multi-code CDMA system with low spreading factor
Author :
Zhao, Junhui ; Lee, Sanghoon ; Wang, Dongming ; You, Xiaohu
Author_Institution :
Sch. of Electr. & Electron. Eng., Yonsei Univ., Seoul, South Korea
Abstract :
In a CDMA system, the RAKE receiver is commonly used to attain the diversity gain by taking advantage of the good correlation properties of the spreading codes. However, at low spreading gains the good correlation properties of the spreading codes are lost and the RAKE receiver performance is severely degraded by interpath interference (IPI). In the case of multi-code CDMA system, the multi-code interference (MCI) exists in the system. In order to suppress MPI and MCI, a novel receiver based on soft-output Viterbi algorithm (SOVA) equalization is proposed in this paper. The SOVA equalization is applied to symbol sequences after RAKE combining and MCI cancellation to effectively eliminate the IPI during transmission of high rate data in wideband DS-CDMA systems. Simulation results show that the proposed receiver significantly outperform the traditional RAKE and RAKE-VA receivers.
Keywords :
3G mobile communication; code division multiple access; equalisers; fading channels; interference suppression; land mobile radio; multipath channels; radio receivers; radiofrequency interference; spread spectrum communication; DS-CDMA systems; RAKE receiver; SOVA equalization; fading channel; interpath interference; low spreading factor; multicode CDMA system; multicode interference; multipath channel; soft-output Viterbi algorithm equalization; spreading codes; symbol sequence; Degradation; Diversity methods; Fading; Interference; Multiaccess communication; Multipath channels; Performance gain; RAKE receivers; Viterbi algorithm; Wideband;
Conference_Titel :
Personal, Indoor and Mobile Radio Communications, 2004. PIMRC 2004. 15th IEEE International Symposium on
Print_ISBN :
0-7803-8523-3
DOI :
10.1109/PIMRC.2004.1368783
