频谱共享系统中基于大尺度信道状态信息的资源优化

Resource optimization with large-scale channel state information for spectrum sharing systems

在基于分布式天线的频谱共享系统(DSSS)中,信道分配和天线选择优化是提升系统性能的重要手段。为了有效控制资源优化的系统开销,研究基于大尺度信道状态信息的联合信道分配和天线选择方法。以次用户的和速率为优化目标建立了优化问题模型,通过变量松弛将整数规划问题转化为线性规划问题求解,降低了复杂度。仿真结果表明:仅仅依靠大尺度信道状态信息仍能够显著提升系统的和速率性能。在实际应用中,系统开销严格受限,该方法为折中系统开销与性能增益提供了有效途径。

In a distributed antenna-based spectrum sharing system （DSSS）, both the channel allocation and the antenna selection are important issues for enhancing system performance. The system overhead can be controlled by a joint channel allocation and antenna selection scheme presented here that is based on only the large-scale channel state information. Particularly, the sum rate of the secondary users （SUs） is used as the optimization objective to formulate the optimization problem. The integer programming problem is transformed into a linear programming problem through variable relaxation to reduce the complexity. Simulations show that the system sum rate is significantly improved using only the large scale channel state information. In practical applications where the system overhead is strictly limited, this scheme offers an effective way to balance the system overhead and performance gain.