POWER LOSS SUPPRESSION ANTENNA CIRCUIT AND PORTABLE TERMINAL PROVIDED WITH THE SAME

摘要

PROBLEM TO BE SOLVED: To provide an antenna circuit which suppresses the increase of a power loss in a transmission/reception changeover part even when radiation resistance is falling down in an antenna by receiving influence from a circumferential environment. SOLUTION: A power loss suppression antenna circuit which comprises the transmission/reception changeover part connected to the antenna is provided with an adjusting circuit 4 which is inserted between the antenna 1 and the transmission/reception changeover part 3. The adjusting circuit 4 adjusts the real number part of impedance when the antenna 1 is viewed from the antenna side connection terminal c of a device 3 to be larger than the real number part of impedance when the antenna 1 is viewed from the power feeding point d of the antenna.