To provide a collinear array antenna, capable of operating over a wide frequency range, by reliably blocking an antenna leakage current to an outer conductor of a coaxial line.
An antenna alignment unit 20 of a collinear array antenna is comprised of a printed circuit board 21 and on a surface of the printed circuit board 21, a microstrip line 22, an open stab 23 and λ/4 impedance aligners 24a, 24b are provided in series. A center conductor of a coaxial feed line is connected to a lower end of the microstrip line 22, and a center conductor of an antenna element is connected to an upper end of the λ/4 impedance aligner 24b. On a backside of the printed circuit board 21, a ground 26 having a predetermined width is provided from the lower end to the upper end. The upper end of the ground 26 is folded to be U-shaped on both sides to constitute a Spertopf 27 planar, and turned over upward from the inside at a position of a length La from the upper end to form a turned-over portion 27a of a length Lb.
Satoshi Kono
Makoto Nakamura
Yoshihiro Fukuhara
Takashi Mine
Toshio Shirane
Sadao Muramatsu
Nobuhisa Nogawa
Kocho Chojiro
Naoki Kono
Katsu Sunagawa
Katsumura Hiro
Tatsushi Sato
Takashi Okada
Mihoko Horiuchi
Takenori Masanori
Takuzo Ichihara
Yamashita Gen