An antenna device for a portable terminal

摘要

An antenna device for a portable terminal, the antenna device comprising a circuit board and an auxiliary board. The circuit board comprises a conductive layer on a first surface and a slit on the first surface where the conductive layer is not present. The auxiliary board is positioned over the slit and above the first surface of the circuit board. A radiation pattern is formed on the auxiliary board such that the radiation pattern at least partially encloses the slit in the plane of the first surface. Even when a radiation element is disposed on the conductive layer, induced current generated around the slit can be controlled to be in the same direction as the signal power, thereby preventing radiation performance from being degraded by an inverse current phenomenon in spite of the disposition of the radiation element on the conductive layer.