针对多用户多输入单输出(MISO,multiple-inputsingle—ouq)m)干扰信道中保密信息泄露问题,提出了理想信道状态信息(CSI,channel state information)下的安全协同波束成形(SCB,secure coordinated beamforming)方案和非理想CSI下的顽健安全协同波束成形(RSCB,robust secure coordinated beamforming)方案。对于理想CSI情况,联合设计最优的协同波束成形向量,最大化最小安全速率。采用半定松弛(SDR,semidefinite relaxation)技术和连续的凸估计(SCA,successive convex approximation)算法得到原始非凸问题的局部最优解。进一步,将该框架扩展到信道向量和信道协方差矩阵存在确定误差的情况,提出的RSCB方案能够最大化最差情况的安全速率。仿真结果验证了所提方案的有效性和顽健性。
For preventing the leakage of confidential messages in multiuser multiple-input single-output (MISO) interferenee eharmels, a secure coordinated beamforming (SCB) scheme was proposed for the perfect channel state informa- tion (CSI) case and a robust secure coordinated beamforming (RSCB) scheme for the imperfect CSI case. Under the perfect CSI, the beam forming vectors at transmitters were jointly optimized to maximize the minimum secrecy rate. The locally optimal solution to the original non-convex problem was obtained using the semidefinite relaxation (SDR) tech- nique and the successive convex approximation (SCA) algorithm. Moreover, the framework was generalized to the case of imperfect CSI with the deterministic errors in both channel vector and channel covariance matrix. The RSCB scheme was used to maximize the worst-case secrecy rate. Simulation results validate the efficacy and the robustness of the proposed schemes.