Channel Capacity of MC-CDMA and Impact of Residual ICI

Koichi ADACHI  Fumiyuki ADACHI  Masao NAKAGAWA 

Publication
IEICE TRANSACTIONS on Communications  Vol.E92-B  No.1  pp.219-227
Publication Date: 2009/01/01
Online ISSN: 1745-1345
Print ISSN: 0916-8516
Type of Manuscript: PAPER
Category: Wireless Communication Technologies
Keyword: 
MC-CDMA,  channel capacity,  ICI cancellation,  theoretical study, 

Full Text: PDF(1.6MB)

Summary: 
Orthogonal frequency division multiplexing (OFDM), which uses a number of narrowband orthogonal sub-carriers, is a promising transmission technique. Also multi-carrier code division multi-access (MC-CDMA), which combines OFDM and frequency-domain spreading, has been attracting much attention as a future broadband wireless access. It was shown that MC-CDMA has lower channel capacity than OFDM, due to inter-code interference (ICI) resulting from orthogonality distortion caused by frequency-selective fading. Recently, many ICI cancellers have been proposed to mitigate the effect of ICI. In this paper, we derive a channel capacity expression for MC-CDMA assuming perfect ICI cancellation taking into account both frequency diversity gain and space diversity gain and compare it to that of OFDM. Furthermore, we derive a channel capacity expression for the case of imperfect ICI cancellation to discuss the impact of the residual ICI.