Title :
A tilted-beam spiral antenna fed through a helical wire
Author :
Nakano, H. ; Okabe, Y. ; Mimaki, H. ; Yamauchi, J.
Author_Institution :
Coll. of Eng., Hosei Univ., Tokyo, Japan
Abstract :
A monofilar-spiral antenna is excited through a helical wire. The antenna characteristics, including the input impedance, radiation pattern, and gain, are analyzed. It is revealed that a purely resistive 50-Ω input impedance is realized by appropriately selecting the pitch angle of the helical wire. A tilted beam, which is often required in mobile communications, is obtained with a gain of approximately 8 dB. The frequency responses of the antenna characteristics are also discussed.
Keywords :
antenna feeds; antenna radiation patterns; antenna theory; beam steering; electric impedance; frequency response; microwave antennas; mobile antennas; spiral antennas; 50 ohm; 6 GHz; 8 dB; EFIE; H-spiral analysis; antenna characteristics; antenna gain; electric field integral equation; frequency responses; helical wire feed; helical wire pitch angle; method of moments; mobile communications; monofilar-spiral antenna; purely resistive input impedance; radiation pattern; tilted-beam spiral antenna; Antenna radiation patterns; Current distribution; Feeds; Frequency; Helical antennas; Impedance; Mobile communication; Pattern analysis; Spirals; Wire;
Conference_Titel :
Microwave Conference, 2001. APMC 2001. 2001 Asia-Pacific
Conference_Location :
Taipei, Taiwan
Print_ISBN :
0-7803-7138-0
DOI :
10.1109/APMC.2001.985466
