Title :
Block coded modulation for the QS-CDMA system
Author :
Kim, Kyeong Jin ; Iltis, Ronald A.
Author_Institution :
Nokia Res. Center, Irving, TX, USA
Abstract :
This paper proposes a novel introduction of the multidimensional multilevel block coded modulation (ML-BCM) to the quasi-synchronous CDMA (QS-CDMA) system, where the code delay uncertainty at the base station is limited to a small number of chips. To improve the performance of the QS-CDMA system, we employ the Leech-lattice based 24-dimensional BCM in the overall BCM-QS-CDMA modulation. The resulting transmitted constellation is more robust to fading. Computer simulation results show a significant coding gain compared to the uncoded and convolutional code based QS-CDMA systems.
Keywords :
block codes; code division multiple access; convolutional codes; delays; modulation coding; QS-CDMA system; code delay uncertainty; coding gain; convolutional code; multidimensional multilevel block coded modulation; quasisynchronous code division multiple access; Base stations; Computer simulation; Convolutional codes; Delay; Fading; Modulation coding; Multiaccess communication; Multidimensional systems; Robustness; Uncertainty;
Conference_Titel :
Signals, Systems and Computers, 2004. Conference Record of the Thirty-Seventh Asilomar Conference on
Print_ISBN :
0-7803-8104-1
DOI :
10.1109/ACSSC.2003.1291946
