Energy efficient cell association in two-tier cellular networks

This paper addresses the multiple-input multiple- output (MIMO) aided heterogeneous mobile network, where a low-complexity iterative cell association algorithm is developed for EE maximising by employing the Lagrange dual concept while considering the minimum QoS provision for each user. Our obtained findings show that the transmit power and the number of users served by macrocells can significantly affect the EE. In addition, findings confirm the superiority of the proposed cell selection algorithm in terms of percentage of users who satisfy the required threshold energy efficiency (about 10% gain at 0.125b/Hz/J).