论文信息 - On the quality factor of strip and line source antennas and its relationship to superdirectivity ratio

On the quality factor of strip and line source antennas and its relationship to superdirectivity ratio

Exact formulas are derived for the quality factor Q of strip and line source antennas. Contrary to popular opinion, none of them is equal to Taylor's superdirectivity ratio \gamma or to \gamma - 1 . But in the case of E -plane strip sources (the complement of the type of strip source treated by Woodward and Lawson) the value of Q is precisely equal to \gamma_{\alpha}^{-1/2}- 1 , where \gamma_{\alpha}^{\beta} is a generalized superdirectivity ratio that reduces to Taylor's \gamma when the edge exponent \alpha and the pattern weighting exponent \beta are both zero. In the case of H -plane strip sources the value of Q is approximately equal to \gamma_{\alpha}^{1/2} - 1 , and for H -plane line sources of vanishing width a it is approximately equal to [(2/\pi) \ln (2.516\lambda/\pi a)]\gamma_{\alpha}^{1} .

D. Rhodes | D. Rhodes

[1] D. Rhodes,et al. On an optimum line source for maximum directivity , 1971 .

[2] On the aperture and pattern space factors for rectangular and circular apertures , 1971 .

[3] G. Borgiotti. On the reactive energy of an aperture , 1967 .

[4] Donald R. Rhodes. On the spheroidal functions , 1970 .

[5] P. Woodward,et al. The Theoretical Precision with which an Arbitrary Radiation-Pattern may be Obtained from a Source of Finite Size , 1948 .

[6] On a new condition for physical realizability of planar antennas , 1971 .

[7] D. Rhodes,et al. On the stored energy of planar apertures , 1966 .

[8] T. Taylor. Design of line-source antennas for narrow beamwidth and low side lobes , 1955 .