PURPOSE: To change tuning frequency by forming an antenna element like a loop, supporting a part of the antenna element so as to change its angle to the plane of polarization and changing the angle.
CONSTITUTION: An element 30 is electrically connected to elements 10, 20 through springs 41, 42 to form an antenna loop. The whole peripheral length of the loop is a little over 1m which is the loop length of 0.3∼0.35 wavelength at the low band of a VHF band, and the antenna loop starts parallel resonance at about 150MHz. Matching by a matching circuit 50 allows the antenna to turn to a band tuning type and cover the whole areas. Since the angle θ of the element 30 to the elements 10, 20 can be changed, the coupling capacity is changed when supposing that the loop is a distribution constant line. Thus, the change of the angle θ can alter the tuning frequency at the low band and cover the whole areas. Thus, an antenna with superior characteristics can be obtained in spite of the small-sized one.
ISHIGAKI YOSHIO
OOUCHI KOUJI
YOSHIKAWA TAKASHI
FUKUZAWA KEIJI
IMAI KAZUHIRO
TAGUCHI YORIMICHI
TSUCHIYA MASAYOSHI
