摘要
研究了对称α稳定分布(SαS)冲击杂波下的多输入多输出(MI MO)雷达目标波达方向(DOA)估计问题,分别提出基于分数低阶最小方差无畸变响应(Fr MVDR)的MI MO雷达DOA估计算法和无穷范数归一化最小方差无畸变响应(Inf-MVDR)算法。Fr MVDR算法,首先进行冲击杂波特征指数的估计,然后使MI MO雷达接收阵列的分数低阶输出功率最小,实现MI MO雷达的DOA估计。为了避免Fr MVDR算法对杂波特征指数估计,提出Inf-MVDR算法,首先用无穷范数对接收信号进行归一化处理,使归一化后的阵列输出功率有界,继而采用传统MVDR算法进行DOA估计。计算机仿真验证了上述两种算法的有效性;同时仿真结果还表明在冲击杂波下,MI MO雷达的空间分集特性可显著提高DOA估计的精度。
This article investigates the issue of direction of arrival （DOA） estimation for multi-input multi-output （MIMO） radar in symmetric a-stable （SaS） clutter. Two algorithms are proposed, i.e. , a fractional lower order minimum variance distortionless response （FrMVDR） DOA estimation algorithm and an infinity-norm normalization MVDR （Inf-MVDR） DOA estimation algorithm. For the FrMVDR algorithm, the characteristic exponent value of the SaS clutter is first estimated, and then the fractional lower order output power of MIMO radar is minimized to realize DOA estimation. To avoid characteristic exponent estimation, another Inf-MVDR algorithm is developed, which first transformes the SaS clutter into a clutter with bounded output power through infinity-norm normalization, then uses the conventional MVDR algorithm to estimate DOA. Computer simulations verify the effectiveness of the two proposed algorithms. The results also show that spatial diversity of MIMO radar can significantly improve the precision of DOA estimation in impulsive clutter.
出处
《航空学报》
EI
CAS
CSCD
北大核心
2009年第8期1454-1459,共6页
Acta Aeronautica et Astronautica Sinica
基金
国家自然科学基金(60472059)
江苏省博士后科研资助计划(0801021B)
中国博士后科学基金(20080431098)
关键词
冲击杂波
MIMO雷达
波达方向估计
分数低阶统计量
无穷范数归一化
impulsive clutter
MIMO radar
direction of arrival estimation
fractional lower order statistics
infinity-norm normalization
