Hybrid precoding with a grouped-adaptive-connected structure in low-earth-orbit satellite system

Elevating energy efficiency (EE) poses significant challenges, primarily associated with implementation complexity and energy consumption. In this paper, we explore a type of hybrid precoder under grouped-adaptive-connected (GAC), In this configuration, divide the antennas into groups and switches dynamically control the links between Radio Frequency (RF) chains and antenna groups. Within the GAC structure, we formulate the design of hybrid precoder as an optimization problem aimed at maximizing EE. Additionally, we divide the task of maximizing EE into two problems of spectral efficiency (SE) maximization and combinatorial optimization. To address the issue, this paper introduces an LEO satellite hybrid precoding algorithm. Additionally, building upon the solution obtained from last problem, we propose a GAC hybrid precoding algorithm (GACHP) based on cross-entropy. Results of simulation indicate that under the GACHP algorithm, system parameters can be configured and adapted to maximize EE of system.