对于基于认知无线电架构的多天线信道估计技术,由于传统零相关序列是在全部频谱可用前提下设计的,在复杂电磁环境的频谱限制下,传统零相关序列部分频域元素发生变化,且不再满足原始序列的周期相关特性,因此不能直接应用于复杂电磁环境的多天线信道估计。该文介绍了多天线通信系统的信道估计算法并指出对理想序列的要求,然后针对复杂电磁环境,即在存在频谱空穴的条件下,联合优化频谱受限和良好周期相关程度两大评价指标,设计出适用的序列集合,作为训练序列应用到认知无线电系统的信道估计算法中,仿真结果验证了新序列集合的有效性。
For channel estimation technology of multiple antenna communication system based on cognitive radio architecture, traditional zero correlation zone sequences (which assume the availability of the entire spectral band) can not be used because their orthogonality will be destroyed by the spectrum hole constraint. This paper introduces the channel estimation algorithm in multiple antenna communication system and points out the requirement of the ideal sequence set, then on complex electromagnetic environment, i.e., under the condition of the existence of spectrum holes, joints optimization evaluation indexes of limited spectrum and good cycle correlation degree, designs a suitable sequence set, which can be applied to the channel estimation algorithm of cognitive radio system. The simulation results verify the effectiveness of the new sequence set.