Utility Fair Optimization of Antenna Tilt Angles in LTE Networks

Abstract

We formulate adaptation of antenna tilt angle as a utility fair optimisation task. This optimisation problem is non-convex, but in this paper we show that under reasonable conditions it can be reformulated as a convex optimisation. Using this insight, we develop a lightweight method for finding the optimal antenna tilt angles, making use of measurements which are already available at base stations, and suited to distributed implementation.

Tilt angle adaptation in LTE networks with advanced interference mitigation

“…However, none of them consider other interference mitigation techniques particularly techniques which are mentioned in Section I in conjunction with the optimisation task, or neither have evaluated the proposed solutions while other interference mitigation techniques are present. In the present paper, we extend our work in [4] by evaluating other contributing factor in interference management.…”

“…Following [4], we select the basestation antenna tilt angles that maximise the following utility fair optimisation P :…”

“…We build upon a recently introduced approach [4] for proportional fair tilt angle adjustment. In [4] we show that although this optimisation problem is non-convex, under certain conditions it can be re-formulated as a convex problem which can be solved efficiently using information which is already available at base stations.…”

“…In [4] we show that although this optimisation problem is non-convex, under certain conditions it can be re-formulated as a convex problem which can be solved efficiently using information which is already available at base stations. For a realistic network configuration we present detailed performance measurements where this proportional fair tilt angle adjustment is applied This material is based upon works supported by the Science Foundation Ireland under Grant No.…”

Impact of base station antenna height and antenna tilt on performance of LTE systems

“…In [9] and [10,11] focus is on UMTS and LTE system performances respectively, with regard to antenna tilting. Tilting plays a crucial role in interference management [12], improves the conditions for handover by minimizing unwanted overlapping with neighboring cells [13]. With tilting, interference at cell boundary can be removed and the received signal strength in region of interest (ROI) can be increased along with minimal interference to neighboring cells [14].…”