| 摘要 |
PURPOSE:To reduce a phase disorder of a radio wave and to improve radiation characteristics by arranging the 1st and 2nd logarithmic period antennas near the focus of a reflector in spatially orthogonal crossing relation, and feeding them independently of each other. CONSTITUTION:Tuning elements 21, 22-2m of the 1st logarithmic period antenna which has a low tuning fequency band, and tuning elements 2m+1-2m of the 2nd logarithmic period antenna which has a high frequency band cross spacially at right angles and are arranged near the focus of a reflector 3. The 1st and 2nd power sorces 41 and 42 feed the 1st and 2nd logarithmic period antennas. When electric power is supplied from the power source 41 which varies in frequency from its upper limit to an intermediate point, the elements 21-2m are energized successively and its radio wave is reflected by the reflector 3 to be radiated into the space. When electric power is supplied from the power source 42 which varies in frequency from the intermediate point to its lower limit, the elements 2m+1-2n are energized successively, and its radio wave is radiated by the reflector 3 and radiated into the space. |
