ANTENNA DEVICE AND COMMUNICATION APPARATUS USING THE SAME

摘要

PROBLEM TO BE SOLVED: To improve the antenna gain of an antenna whose resonance frequency is low and to make the variation of the antenna gains in the plural antenna small by mounting the plural surface mount antennas on the substrate and arranging the antenna whose resonance frequency is lower in a position nearer to the end part of the substrate. SOLUTION: An antenna device 1 is constituted of the two surface mount antennas 3 and 4 mounted on the substrate 2. The resonance frequency of the surface mount antenna 3 is lower than the resonance frequency of the surface mount antenna 4. The antenna 3 is arranged near the corner part of the substrate 2 and the antenna 4 is arranged adjacently to the antenna 3 in a direction detached from the corner part. The route of the electric line of force between the opening end of the radiation electrode in the antenna 3 and a ground electrode 6 becomes partially long and the concentration of electric fields is relieved. Since the leakage of the electric field increases by the amount, a radiation resistance drops and the antenna gain is improved.