密集小区技术是满足未来高容量、高能效蜂窝通信的关键技术之一。在密集小区场景下，虽然单个基站的能耗降低了，但是由于基站总数大幅度增多，蜂窝网络的总能耗还是会随业务的增多而提高。基于用户业务排队的用户分配、频谱分配和功率分配可以有效地提升系统性能。该文研究在多载波正交信道下，基于用户业务排队进行用户调度、载波分配、功率分配来降低系统长时间的总能耗，同时保证用户业务传输的需求。通过利用Lyapunov优化理论，把问题转化成一个混合整数规划问题，并给出了多载波正交信道下的用户调度、载波分配、功率分配的算法。仿真结果验证了该算法能够降低系统能耗，同时与以优化系统和速率为目标的算法具有一致的系统和速率。
The small-cell technology is one of the key technologies in cellular communications that should provide high system capacity and high energy efficiency. Although the energy consumption of one single base station diminishes in small cell networks (SCNs), the total energy consumption still increases along with the growth in traffic, as the number of base stations increases quickly. Queue state information (QSI) could be utilized for user scheduling, carrier allocation, and power allocation to enhance system performance. In this study, QSI is used to minimize the time average of the total power expenditure in multi-carrier SCNs, where no inter-cell interference exists, while satisfying the traffic demand. The problem is formulated according to Lyapunov optimization theory into a mixed integer programming problem. An optimal algorithm is given for user scheduling, carrier allocation, and power allocation in each slot. Simulations verify that the algorithm reduces the energy consumption with a similar sum rate as the algorithm aiming to maximize the system sum rate.
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