摘要
带平衡器（Ｂａｌｕｎ）的直臂振子辐射元在Ｅ面扫描时出现扫描盲点已由理论和实验得到证明［１，２］。本文研究盲点的消除，用矩量法（ＭＭ法）计算了包括平衡支杆效应的直臂振子的５×３个辐射元的小面阵的中心振子的阵波瓣。计算结果证实Ｅ面阵波瓣在出现栅瓣前出现明显的凹点，即出现扫描盲点。计算还表明若在辐射无间加高度为ｈ的Ｈ面寄生杆，则可控制Ｅ面阵波瓣的凹点的值。当ｈ／λ＜０．２５将可减弱或消除盲点现象。而当ｈ／λ≈０．１４可在扫描域内消除盲点，且有最小输入阻抗的扰动。７×７个辐射元小面阵实验结果表明当取ｈ／λ０＝０．１３时在１６．７％频带内Ｅ面±６０°扫描的中心辐射元的有源阻抗的电压驻波比（Ｖ．Ｓ．Ｗ．Ｒ）小于２．０；在Ｅ面±６０°扫描和Ｈ面±５０°扫描的扫描域内，Ｖ．Ｓ．Ｗ．Ｒ≤２．２，其中９５％Ｖ．Ｓ．Ｗ．Ｒ≤２．０，而当ｈ／λ０＝０时Ｅ面扫描大于４８°时Ｖ．Ｓ．Ｗ．
This paper investigates the elimination of blind spots for a center-fed dipole with a balun arranged in a rectangular grid array. It is known that for a center-ted dipole with balun blind spots can occur in a planar phased -array antenna pattern. Amethod of moments model (MM) is used. to calculate the theoretical element gain patterns in a 5 × 3 array of center-ted dipoles with balun. The theoretical data indicate blind spots in array element gain patterns. When H- plane isolating posts having heights of 0. 14λ positioned between the dipole elements, the theoretical data indicate the elimination of the blind spots and minimum variation of active input impandance. The theoretical data are in good agreement with measurement. Within E-plane for scan angles up to ± 60°and over 16.7% bandwidth, the V. S. W. R of active impedance match is less than 2. 0. The V. S. W. R. of active impedance match is less than 2. 2 within E- plane ± 60°and H- plane ± 50°scan sector and over 16. 7% bandwidth.
出处
《电波科学学报》
EI
CSCD
1995年第1期33-38,共6页
Chinese Journal of Radio Science
关键词
相控阵天线
宽带宽角
扫描
盲点
Dipole phased array, Blind spot, H-plane isolating post, Broadband and wide angle scan impandance match
