Capacity analysis and optimization of fractional frequency reuse under energy efficiency constraints

Abstract

The densification of base station deployment for the next generation cellular networks raises the motivation to design energy efficient networks. In practice, most of the orthogonal frequency-division multiple access (OFDMA) based cellular networks employ fractional frequency reuse (FFR) to coordinate the resource block allocations. In this paper, we address stochastic geometry-based analysis and optimization of cellular networks employing OFDMA and FFR under energy efficiency constraints. Our analysis includes results for the average total capacity of a base station and the average capacity in the worst signal-to-interference-plus-noise ratio (SINR) region. Through the analytical derivations, two different optimization problems are formulated with the energy efficiency considerations. Numerical results indicate that resource block allocation in FFR is more energy efficient than transmit power adjustment for fulfilling the energy consumption and capacity constraints.