Abstract
We investigate the optimal chip rate of power or rate adapted direct-sequence code division multiple access (DS/CDMA) communication systems in Nakagami fading channels. We find that the optimal chip rate that maximizes the spectral efficiency depends upon both the channel parameters, such as multipath intensity profile (MIP) and line-of-sight (LOS) component, and the adaptation scheme itself. With the rate adaptation, the optimal chip rate is less than 1/Tm
, irrespective of the channel parameters, where 1/Tm
is multipath delay spread. This indicates that with the rate adaptation, correlation receiver achieves higher spectral efficiency than RAKE receiver. With the power adaptation, however, the optimal chip rate and the corresponding number of tabs in RAKE receiver are sensitive to MIP and LOS component.
, irrespective of the channel parameters, where 1/Tm
is multipath delay spread. This indicates that with the rate adaptation, correlation receiver achieves higher spectral efficiency than RAKE receiver. With the power adaptation, however, the optimal chip rate and the corresponding number of tabs in RAKE receiver are sensitive to MIP and LOS component.
| Translated title of the contribution | Optimal Chip Rate of Power and Rate Adapted DS/CDMA Communication Systems in Nakagami Fading Channels |
|---|---|
| Original language | Korean |
| Pages (from-to) | 128-133 |
| Number of pages | 6 |
| Journal | 한국통신학회논문지 |
| Volume | 35 |
| Issue number | 2 |
| State | Published - Feb 2010 |