On the Optimal Placement of Base Station Antennas for Distributed Antenna Systems

In this letter, we aim to optimize the placement of base station (BS) antennas for maximizing the average ergodic sum capacity of a multi-user distributed antenna system (DAS). Different from previous studies where deterministic optimization approaches were usually taken, we formulate the BS antenna placement as a stochastic optimization problem, and propose a stochastic-gradient-descend-based algorithm to effectively solve it. Simulation results demonstrate that the proposed algorithm converges fast and provides significant gains in average ergodic sum capacity over the existing representative BS antenna placement schemes.