非理想信道下的分布式认知多小区波束形成

针对非理想信道下的波束形成问题,将传统稳健波束形成设计推广至认知多小区,在认知干扰和认知用户速率约束下,构造基于最小化认知系统总功率准则的优化问题.通过半定松弛及S-Procedure算法将其转化为凸优化问题,并采用Primal分解将该凸优化问题分解为一组独立的子问题,从而实现了分布式求解,在降低复杂度的同时减少所需的反馈信息.仿真结果表明:算法不仅对信道误差稳健,而且收敛速度很快.

Beam Forming of the Distributed Cognitive Multi-CellSystem for Imperfect Channel

To solve the beam forming problem for imperfect channel, the robust beam forming design method for conventional system is extended to cognitive multi-cell system. Under the constraints of cognitive interference and cognitive users’ rate, the optimization problem is formulated based on the criterion of minimization of cognitive system’s total power. The problem is converted to a convex optimization problem by means of semi-definite relaxation and S-Procedure algorithm, and is decomposed into a group of independent sub-problems by using Primal decomposition. So then a distributed solution is achieved and both computational complexity and required feedback information are reduced. Simulation results show that the algorithm is not only robust to channel errors but also convergences quickly.