Optimal thresholds for Discrete Power Levels using Adaptive Modulation in presence of Imperfect Channel State Information

Majority of researches on power allocation have been applied to continuous power scheme. However, the hardware complexity is an obstacle in using continuous power, so discrete power, especially in cellular systems, has a very remarkable role to reduce the feedback rate. On the other hand, assuming that the receiver mobility causes alternation in determination of transmission thresholds and power levels, and thus elimination of it, leads to reduction in system’s spectral efficiency (SE). As a result, this research will introduce a method based on adaptive modulation (AM) and some discrete levels of power while all information of channel state are not accessible. Numerical results show that proposed scheme results in a better efficiency in comparison to other adaptation schemes; however, it contains less feedback rate

Keywords:

Adaptive Modulation , Continuous and Discrete power , Feedback Rate , Imperfect Channel State information