摘要
本文首先推导了QAM信号信噪比估计的克拉米罗下限,然后以两个统计量比值与信噪比关系的研究为基础,提出了一种QAM信号的盲信噪比估计算法.虽然高阶QAM信号的信噪比估计需要较多的观察数据才能得到准确的信噪比估计值,但是本算法不需要额外的存储器来存储这些数据;并且该算法具有非常低的运算复杂度.文章还以多种QAM信号为例进行了具体的分析和计算机仿真,分析和仿真的结果表明在合适的观察数据长度下,该算法对文中测试的各种QAM信号都能进行有效估计.
The Cramer-Rao Lower Bounds(CRLB) of signal-to-noise-ratio(SNR) estimation for quadrature amplitude modulation (QAM) signals is derived,and then a blind SNR estimation algorithm for QAM signals base on a statistical ratio of observables over a block of data is present.Although the SNR estimation for QAM signals needs large numbers of observation symbols for good performance,the algorithm presented in this paper needn't any extensive memory to store those data.And the algorithm has very low computational complexity.The detail analysis and computer simulation for some kinds of QAM signals are also presented.It can be seen from the results that when there are enough observation data,this algorithm can work effectively for all kinds of QAM signals tested in this paper.
出处
《电子学报》
EI
CAS
CSCD
北大核心
2005年第4期758-761,共4页
Acta Electronica Sinica
关键词
QAM信号
信噪比估计
克拉米罗限
数据拟合
quadrature amplitude modulation signals
SNR estimation
Cramer-Rao bounds
data fitting
