🤖 AI Summary
This work addresses the joint optimization of mechanical mobility and electronic beam steering in six-dimensional movable antenna (6DMA) base stations. To this end, a hybrid architecture and a two-timescale optimization framework are proposed: at the long timescale, the antenna array positions are optimized based on large-scale user distribution, while at the short timescale, beam pattern selection is refined using instantaneous channel state information. This approach uniquely integrates mechanical reconfigurability with electronic tunability, enabling simultaneous wide-angle coverage and rapid beam alignment through an alternating optimization algorithm enhanced by Monte Carlo sampling. Simulation results demonstrate that the proposed scheme significantly outperforms existing benchmark methods in terms of average sum rate.
📝 Abstract
This letter proposes a hybrid mechanically and electronically tunable six-dimensional movable antenna (6DMA) base station (BS) architecture for future wireless communication networks. Such BS consists of multiple antenna arrays that are mechanically movable along a circular rail to adapt to the horizontal user hotspots, and each array is equipped with pattern reconfigurable antennas (PRAs) that are capable of electronically switching among a set of specified beam patterns to cater to the instantaneous user channels. The mechanical adjustment provides wide-angle coverage but suffers from slow response, while the electronic tuning enables rapid beam reconfiguration but with limited angular range. To effectively combine their complementary advantages, we propose to jointly design both mechanical and electronic configurations to maximize the average sum-rate of users via a two-timescale optimization approach, in which the array positions are optimized on the long timescale according to large-scale user distribution statistics, and the pattern selection vectors are optimized on the short timescale to enable fast beam alignment based on the instantaneous user locations. An alternating optimization algorithm based on the Monte Carlo sampling method is developed to solve the problem efficiently. Finally, simulation results show that our proposed design achieves significant performance gains over various benchmark schemes.