脉冲超宽带(UWB)跳时系统的频域信道估计

Channel Estimation in Frequency Domain on IR-UWB TH System

提出一种基于序列和的最大似然(ML)频域信道估计算法,该算法可适用于对跳时UWB通信系统进行基于训练序列的信道估计和盲信道估计,大大简化了运算的复杂性。在仿真中比较了基于理想信道估计、基于一般的频域信道估计以及基于序列和的ML频域信道估计的性能。结果显示,在频域的估计过程中,对发射信号的频谱设定适当的可信门限后,可以获得与直接进行频域信道估计相似的性能。

The proposed estimation algorithm is based on the maximum-likelihood criterion of the sum of sequences and is applied to two different scenarios ： either with known symbols （ DA estimation） or with unknown symbols （ NDA estimation）. The effects of the estimation errors on the performance of receiver are assessed by simulation by comparing the receiver bit-error rate with either perfect channel estimates, general frequency domain estimates or imperfect estimates as obtained from the proposed algorithms. The results show that with the proposed algorithm, the performance can approach the same as that by general frequency domain algorithm as long as threshold for frequency estimates is set properly.