Antenna matching device

摘要

An antenna apparatus (10; 20; 30) having a predetermined impedance is provided. The apparatus has a chip antenna (11) including a conductor (16) and a mounting board (12) on which the antenna is mounted. A ground pattern (13) and a microstrip line (14) are formed on the board (12). A feeding terminal (17) for applying a voltage to the conductor (16) is deposited on the surface of the antenna. Solder may be used to connect the feeding terminal (17) of the antenna to the microstrip line (14) formed on the board (12). A capacitance-generating device (19; 21; 31), e. g., a dielectric resin (19) or capacitor (21) is disposed between the microstrip line (14) connected to the feeding terminal (17) of the antenna and the ground pattern (13). A capacitance is thus generated between the microstrip line (14) and the ground pattern (13) thereby enabling regulation of the antenna apparatus impedance and bandwidth.