非连续正交频分复用系统次优导频设计
Suboptimal pilot design in NC-OFDM systems
-
摘要: 在非连续正交频分复用系统中,为了改善信道估计的性能并尽可能地降低计算复杂度,基于最小化最小二乘信道估计均方误差(Mean Square Error,MSE)的准则提出了一种次优导频设计方法.该方法利用凸映射解决了导频位置优化设计的非凸问题,求得符合三次函数关系的非均匀分布次优导频位置,并推导导频位置已知条件下的最优导频功率分布.仿真结果表明:所提次优导频设计方法与现存导频设计方法相比,能够获得较好的信道估计MSE性能,且具有计算简单的优势.Abstract: In order to improve the performance of non-continuous orthogonal frequency division multiplexing(NC-OFDM)systems with lower complexity, one suboptimal pilot design is presented minimizing the channel estimation mean square error(MSE)in this paper.Firstly, the non-convex problem of pilot position optimization design is converted by one convex mapping method;then based on this analysis the suboptimal non-uniform pilot positions meeting the cubic function are obtained,and the expression of the optimal pilot power distribution is derived.The simulated results have shown that the proposed suboptimal pilot design can achieve better channel estimation MSE performance, and has an advantage of lower computational complexity compared with the existing pilot design methods.