Koh Hashimoto

Millimeter-wave band slot antenna on shielded BGA package

High-speed short-range wireless communication systems utilizing the 60-GHz band are expected. An installation of a 60-GHz transceiver into a mobile terminal with high packaging density is one of the promising usages. Electromagnetic noise in the mobile terminals is an important issue, because it may degrade the communication quality of the 60-GHz transceiver. This paper presents a novel antenna-in-package solution realizing both efficient radiation of millimeter waves and high shielding effectiveness to electromagnetic noises. The antenna is composed of U-shaped slots cut on the shielded ball grid array package. The antenna is designed to have a wide-angle radiation characteristic in the horizontal plane. The measured antenna gain of the fabricated antenna is from 2.9 to 5.2 dBi in the frequency range from 57 to 65 GHz.

Automatic tunable antenna system using MEMS variable capacitors and a probe triggered by TPC

Built-in antennas in mobile equipment are often subject to changes in input impedance due to the proximity of objects, e.g. a users hand/head, a desk, etc. To compensate this mismatch, an automatic tunable antenna system using Micro-Electro-Mechanical System (MEMS) variable capacitors and a probe is proposed in this paper. The system controls MEMS variable capacitors based on the received power of the probe and triggered by the Transmission Power Control (TPC). A prototype using a square-law detector, an Analog-to-Digital Converter (ADC), a Field Programmable Gate Array (FPGA) and a matching circuit containing MEMS variable capacitors is also demonstrated.