A Load-Aware Base Station Switch-Off Technique for Enhanced Energy Efficiency and Relatively Identical Outage Probability

Abstract

Switching off base stations is a popular approach to improving the energy efficiency a network. The challenge is how to determine which and how many base stations to switch off given a network configuration while ensuring that the network coverage is not compromised. Different algorithms have been formulated to solve this challenge ranging from load-aware algorithms to random selection. Results show that load-aware algorithms have better performance. Most algorithms assume universal frequency reuse by all base stations even in the case of heterogeneous networks. In this paper we assume an indoor, femtocell network where subcarrier allocation is based on an existing subcarrier allocation technique which ensures maximum reuse. A load-aware base station switch-off algorithm is developed that uses the allocation matrix when all base stations are active and an estimate of required subcarriers by each base station to determine which base stations to switch off. It will be shown that even without any power control, the proposed technique can result in significant energy savings for lower femtocell densities.

Energy-Efficient On–Off Power Control of Femto-Cell Base Stations for Cooperative Cellular Networks

“…The most straightforward way to improve the EE of MCSs is to simply turn off base stations (BSs) whose operation is unnecessary in view of overall network performance [1,[13][14][15][16][17][18][19][20]. Through the shutdown of BSs, electricity consumption can be reduced significantly because more than half of total electricity consumption in MCSs is caused by BSs.…”

“…Through the shutdown of BSs, electricity consumption can be reduced significantly because more than half of total electricity consumption in MCSs is caused by BSs. Consequently, on-off power control schemes for BS have been extensively studied in previous literature, especially in the context of GCNs [1,3,[13][14][15][16][17][18][19][20][21][22]. The on-off power control schemes for BSs can be divided into two categories: which are statistical scheme and adaptive scheme.…”

“…On the other hand, in an adaptive scheme, BSs are flexibly turned off based on the real-time information, e.g., incurred traffic load on each BS [13][14][15]19]. For example, certain BSs can be turned off for the period when the traffic load incurred at those BSs is sufficiently low [13,14].…”

“…Due to its importance, the adaptive on-off power control scheme has recently been the subject of extensive investigation [15][16][17][18][19][20][21][22]. In [21], the on-off state of BS which operates based on the renewable generation, e.g., wind power, was optimized where the main objective is to minimize the on-grid power consumption.…”

“…Furthermore, in [18], the adaptive FBS switching-off scheme was considered for the indoor FBS in which the operation of redundant FBS is stopped by examining the achievable throughput. In addition, the switching-off of FBS was determined based on the results of subcarrier allocation such that FBS with a small number of allocated subcarriers, i.e., low traffic FBS, is turned off in [19]. Finally, the authors of [6] considered the on-off power control scheme for FBS in order to improve EE, where the FBS is turned on only when active MS is nearby.…”