| 摘要 |
PURPOSE:To obtain an effective course structure in an airport having bad obstacle conditions by adopting a double frequency system. CONSTITUTION:In the directional pattern EN of an array antenna consisting of 2N+1 elements arrayed at an about equal interval, EN(u) is expressed by the formula (3) if the current distribution factor of each element, using wavelength and radiating direction are An, lambda and theta respectively and u=sintheta and d/lambda=1/U are defined. A new current distribution factor Cn weighted by delta<m> on the current distribution factor An of each element is found by the formula (9) by adjusting said pattern by the mean value method of (m) times based on the formula (3) and selecting a function for realizing a required carrier directional pattern. To find a required directional pattern, it is necessary to satisfy 1.0<= m/Z<2=3.0 and 0.74<=Ndelta<=1.44(delta=[¦U2¦-¦U1¦)/U]. When the number of elements is 2N, simular formulas are led out. |
