  With the rapidly increasing number of deployed LTE femtocell base stations
(FBS), energy consumption of femtocell networks has become a serious
environmental issue. Therefore, energy-efficient protocols are needed to
balance the trade-off between energy saving and bandwidth utilization. The key
component of the desired protocol to prevent both energy and bandwidth waste is
interference mitigation, which, nevertheless, most previous work has failed to
properly consider. To this end, in this paper, we manipulate user equipment
(UE) association and OFDMA scheduling with a combination of interference
mitigation. Recognizing the NP-hardness of the problem, we propose two
distributed algorithms with guaranteed convergence. Extensive simulations show
that our algorithms outperform the alternative algorithms in multiple metrics
such as utility, power consumption, and convergence speed.
