Internal broadband antenna for hand-held terminals with reduced gain in the direction of the user´s head

We analyze the performance of a radiation-coupled dual-L antenna (RCDLA). It is mounted on the back side of the hand-held terminal, making use of the metallic housing as a shielding structure. In terms of shielding effectiveness and radiation characteristics, our simulations and measurements show a similar performance of this structure compared to the short circuit planar inverted-F antenna (FS-PIFA). Placement of the antenna on the back side of the housing, instead of the terminal top, results in a radiation pattern that points away from the user. The gain in the direction of the users head is about 10 dB less than in the main beam region