基于多项式模型的SCMA系统信道估计

Channel estimation based on polynomial model for SCMA system

针对无线移动信道下的稀疏码分多址(sparse code multiple access, SCMA)系统,提出了一种基于内插导频和自适应多项式的信道估计方法。该方法基于使用ZC序列的导频信号模型,采用自适应多项式模型对信道进行拟合,从而能够显著提高信道估计的准确性。通过仿真,研究了SCMA信道估计性能和移动速度的关系,确定了拟合多项式阶数。仿真结果表明,在瑞利衰落信道前提下,该方法与最小二乘(least squares, LS)估计算法相比,能通过多项式模型,较好地拟合实际信道,因此更灵活地适用于高速移动场景。

A channel estimation method based on assisted-pilot and adaptive polynomial is proposed for sparse code multiple access (SCMA) systems.The method is based on the pilot signal model using the ZC sequence and can accurately estimate the channel information based on adaptive polynomial mode.The relationship between SCMA channel estimation performance and mobile speed is studied by simulation.The polynomial order is also investigated.The simulation results show that compared with the least-squares (LS) estimation algorithm,the proposed method can fit the actual channel well by the polynomial model,so it is flexible for high speed mobile environment.