CAJ | 학술논문

稀疏阵能够获得更大的阵列孔径,但常规波束形成(Conventional Beam-Forming, CBF)对非均匀稀疏阵测向时会出现方位模糊.提出了一种基于最小方差无畸变响应(Minimal Variance Distortionless Response, MVDR)同局部非稀疏的非均匀稀疏阵(Non-Uniform Sparse Array, NUSA)的设计相结合来抑制方位模糊的方法(NUSA+MVDR),对其无方位模糊现象进行了理论分析,表明 MVDR 这一非线性处理方法对伪峰有很好的抑制能力.针对一种典型的NUSA(Typical NUSA, TNUSA),进行了TNUSA+MVDR数值仿真实验,其结果和理论分析一致,表明:① MVDR有很强的 NUSA 检测能力,在所给仿真条件下,等效阵元间距为 50 倍波长时,仍能很好地抑制方位模糊;② TNUSA+MVDR较阵元数相同的均匀非稀疏阵列的CBF和MVDR有更高的方位分辨力;③阵元数一定, TNUSA+MVDR 方位分辨力随着等效间距增加而提高,最小可分辨角度反比于等效间距;④ 等效间距一定, TNUSA+MVDR 方位分辨力随阵元数增加而增加.海上实验在等效阵元间距为 10 倍波长条件下部分验证了NUSA+MVDR的检测性能.
희소진능구획득경대적진렬공경,단상규파속형성(Conventional Beam-Forming, CBF)대비균균희소진측향시회출현방위모호.제출료일충기우최소방차무기변향응(Minimal Variance Distortionless Response, MVDR)동국부비희소적비균균희소진(Non-Uniform Sparse Array, NUSA)적설계상결합래억제방위모호적방법(NUSA+MVDR),대기무방위모호현상진행료이론분석,표명 MVDR 저일비선성처리방법대위봉유흔호적억제능력.침대일충전형적NUSA(Typical NUSA, TNUSA),진행료TNUSA+MVDR수치방진실험,기결과화이론분석일치,표명:① MVDR유흔강적 NUSA 검측능력,재소급방진조건하,등효진원간거위 50 배파장시,잉능흔호지억제방위모호;② TNUSA+MVDR교진원수상동적균균비희소진렬적CBF화MVDR유경고적방위분변력;③진원수일정, TNUSA+MVDR 방위분변력수착등효간거증가이제고,최소가분변각도반비우등효간거;④ 등효간거일정, TNUSA+MVDR 방위분변력수진원수증가이증가.해상실험재등효진원간거위 10 배파장조건하부분험증료NUSA+MVDR적검측성능.
Sparse array can get large aperture, but it will also lead to azimuth ambiguity if conventional beam-forming (CBF) is used for non-uniform sparse array. In order to solve this problem, the method called NUSA+MVDR is pre-sented, in which minimal variance distortionless response (MVDR) is applied to non-uniform sparse array with local non-sparse element distribution(NUSA), and theoretical analysis indicates that false peaks could be suppressed by this method. For a typical NUSA(TNUSA), numerical simulations are carried out, and the results, which are in good agreement with theoretical analysis, show that: 1. MVDR has great detection performance, as the equivalent element spacing reaches to 50 times of the wavelength under the simulation condition given in this paper, TNUSA+MVDR can still suppress azimuth ambiguity perfectly; 2. Azimuth resolution of TNUSA+MVDR is higher than that of CBF and MVDR for a uniform non-sparse array with the same number of elements; 3. For the given number of array elements, the azimuth resolution of TNUSA+MVDR improves with the increase in equivalent element spacing, and the mini-mum resolvable angle is inversely proportional to the equivalent element spacing; 4.For the given equivalent element spacing, the azimuth resolution of TNUSA+MVDR improves with the increase in the number of array elements. The detection performance of NUSA+MVDR is verified partially by marine experiments under the condition where the equivalent array element spacing is 10 times of the wavelength.