| 摘要 |
PURPOSE:To prevent generation of grating robe by means of the min. number of element antennas by making the array interval of element antennas smaller as the element antenna gets close to the endmost position in a circular arc type array antenna. CONSTITUTION:Generally, element interval d by which 2 element arrays do not generate grating robe, when beam scanning angle is thetaM and wave length is lambda, is d<lambda/(1+sinthetaM). Therefore when the interval of optional 2 neighboring element antennas of the ith and (i+1)th element antennas, for example interval d2 between element antennas 12 and 13, is defined as d2<lambda/{1+sin(thetaM+theta2)} if the angle made by the center axis of 2 element arrays and center axis 2 of the circular type array antenna is theta2, generation of grating grobe can be prevented as a whole antenna by means of the number of element antennas of min. requirement. |
