Hiroyuki Tamaoka, Hiroki Hamada and Takahiro Ueno
Antennas for mobile phone handsets are generally required to have such characteristics as compactness, complete built-in mountability, multiband operation and environmental isolation, as well as broad bandwidth and high efficiency. However, conventional technologies represented by planar inverted-F antenna (PIFA) are reaching their limit of improvement to meet the market requirements. In an effort to better such a situation, we have developed a novel model of antenna --for single band and multiband operation-- best suited for mobile phone handsets through full utilization of electromagnetic simulation techniques. The antenna developed here features the use of a specific radiator pattern and a resin of high dielectric constant, both belonging to Furukawa Electric's proprietary technologies, and it was confirmed that the performance of the antenna is comparable to that of conventional PIFA, whereas its volume is as small as one tenth of its counterparts.