基于子空间距离的低复杂度码字搜索方法

Low Complexity Codeword Search Algorithms Base on Subspace Distance

针对有限反馈预编码多用户MIMO的码字搜索问题,该文提出两种基于子空间距离的码字搜索算法。首先证明了子空间距离与弦距的等效性,然后分析了弦距计算与两种子空间距离计算方法的运算复杂度。仿真证明与传统的的弦距计算相比子空间距离的计算复杂度较低,并且根据不同的硬件实现和发射天线数目可在两种子空间距离算法中选择复杂度较低的一个。

Two subspace distance calculation algorithms are proposed for codeword search of limited feedback precoding multi-user MIMO systems. The equivalence of subspace distance and chordal distance are first proved, then the complexity of chordal distance calculation and proposed two subspace distance calculation algorithms are analyzed. Simulation results verify that subspace distance calculation algorithms cost fewer operations. Further more the proper one of two proposed algorithms can be chosen based on different hardware implementations and transmitting antenna numbers.