An Efficient Density Weighting Approach for Side-lobe Level Suppression of Linear Array Antennas
Most likely, there are two techniques existed to reduce the side lobe level (SLL) of array antennas: The conventional excitation amplitude tapering (AT) and the unusual element space density tapering (DT). The AT technique, such as triangular, cosine, cosine-square and raised-cosine amplitude distributions, as well as the Dolph-Chebyshev or Taylor current coefficients, provides efficient means for low SLL (LSLL) and ultra-low SLL (ULSLL) pattern synthesis, and also affords significant dynamic ranges control of the aperture distributions. The feed network, however, becomes complicated and narrow bandwidth, the aperture efficiency decreased rapidly as the amplitude getting much tapered. The DT technique offers another way for limited SLL reduction while the aperture efficiency is maintained, the antenna is a uniformly excited non-uniformly spaced array with element positions thinned from the center element (odd number array) or center two elements (even number array), the main advantage is that it simplifies the bulk and lossy feed network. In this paper, A uniformly excited symmetrical array antenna, which is compose of a uniform central sub-array (central part) and two density tapered side sub-arrays (side parts), is presented for SLL suppression, a power function characterized by two-parameter is employed to express the increments between adjacent elements of the two side parts, the optimum values of the two parameters are searched by the Min-max method according to the peak SLL. Numerical examples are given for the cosine-element, one half wavelength least spacing, and 4-element central part arrays, 8-, 10-, and 12-element arrays are simulated; Dolph-Chebysheve liked patterns are observed, -19.5 dB, -20.8 dB and -21.4 dB SLLs are achieved, respectively.
Xiaomiao Zhang Kwai Man Luk Weiwei Song Wei Zhao Yang Liu
National Key Laboratory of Antennas and Microwave Techniques,Xidian University Xian 710071,Shaanxi Department of Electronic Engineering,City University of Hong Kong 83 Tat Chee Avenue,Kowloon,Hong Ko
国际会议
Progress in Electromagnetics Research Symposium 2008(2008年电磁学研究新进展学术研讨会)(PIERS 2008)
杭州
英文
1-4
2008-03-24（万方平台首次上网日期，不代表论文的发表时间）