Abstract
The performances of direct sequence-code division multiple access (DS-CDMA), multicarrier-CDMA (MC-CDMA) and multicarrier-direct sequence-CDMA (MC-DS-CDMA) systems under different channel conditions are compared in this work. In a frequency-selective slowly fading channel, MC-CDMA and MC-DS-CDMA outperform DS-CDMA, since the former two systems partition the frequency band into sub-channels, each of which has a nearly constant frequency response. Thus, MC-CDMA and MC-DS-CDMA do not suffer much from the multipath effect. The performance of MC-CDMA and MC-DS-CDMA can be further differentiated in severe fading conditions. In a frequency-selective fast fading channel, the larger spreading ratio of MC-DS-CDMA in the time domain prevents the chip duration of a sub-carrier from being longer than the channel coherence time. Hence, the sub-carrier orthogonality is maintained in MC-DS-CDMA, leading to its better performance in this case.
| Original language | English |
|---|---|
| Pages (from-to) | 42-52 |
| Number of pages | 11 |
| Journal | Proceedings of SPIE-The International Society for Optical Engineering |
| Volume | 4740 |
| DOIs | |
| Publication status | Published - 2002 |
| Externally published | Yes |
Keywords
- Code division multiple access (CDMA)
- Direct sequence-CDMA (DS-CDMA)
- Frequently-selective
- Multicarrier-CDMA (MC-CDMA)
- Multicarrier-direct sequence-CDMA (MC-DS-CDMA)
- Rayleigh fading channel
- Time-selective
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Computer Science Applications
- Applied Mathematics
- Electrical and Electronic Engineering