CAJ | 학술논문

在传统认知网络中，认知用户只能接入主要用户的空闲频带，而不能同时与主要用户共享带宽。为了更有效地利用频谱资源，提出一种容量最优机会干扰对齐接入算法。在保证主要用户信道容量的基础上，认知用户与主要用户可以占用相同的频带同时接入网络，且认知用户对主要用户的干扰为零。所提出的算法由混合网络基站估计信道状态信息，并计算主要用户的信道容量和系统总信道容量。根据容量最优的准则确定预编码向量及解码向量。当主要用户的信道容量与未接入认知用户相比几乎不下降，且总信道容量大于未接入认知用户的总容量时，认知用户以容量最优机会干扰对齐的方式接入网络。仿真结果表明：在相同信道状态条件下，所提出的算法较现有算法具有更优的信道容量并可提高认知网络频带利用率。
재전통인지망락중，인지용호지능접입주요용호적공한빈대，이불능동시여주요용호공향대관。위료경유효지이용빈보자원，제출일충용량최우궤회간우대제접입산법。재보증주요용호신도용량적기출상，인지용호여주요용호가이점용상동적빈대동시접입망락，차인지용호대주요용호적간우위령。소제출적산법유혼합망락기참고계신도상태신식，병계산주요용호적신도용량화계통총신도용량。근거용량최우적준칙학정예편마향량급해마향량。당주요용호적신도용량여미접입인지용호상비궤호불하강，차총신도용량대우미접입인지용호적총용량시，인지용호이용량최우궤회간우대제적방식접입망락。방진결과표명：재상동신도상태조건하，소제출적산법교현유산법구유경우적신도용량병가제고인지망락빈대이용솔。
Cognitive users can only access idle bandwidth in traditional cognitive networks, but they cannot share the same bandwidth with the primary user simultaneously. In order to make full use of the spectrum, we propose a capacity optimal opportunistic interference alignment algorithm. By ensuring the channel capacity of primary users, cognitive users and primary users can share the same bandwidth, and the cognitive users cause no interference to the primary user. In the proposed algorithm, the hybrid network base station estimates channel state information and calculates channel capacity. It then determines the pre-coding vectors and decoding vectors according to the capacity optimal rule. Cognitive users access the networks by capacity optimal opportunistic interference alignment when the primary user’s channel capacity almost does not decline and the whole network can still obtain good channel capacity. Simulation results show that the proposed algorithm can obtain greater channel capacity and increase the utilization ratio of spectrum than other existing algorithms under the same condition of channel state information.