Recently, with the development of wireless communication components mobile handsets become small and show high performance. The antenna, however, has the physical limitations that its length depends on the wavelength related to frequency so that has some difficulties in miniaturizing. But keeping pace with a trend miniaturizing mobile handsets, many studies are contributed to the small antenna. Especially the internal small antenna attracts much attention.
In this thesis, the internal small antenna is proposed and designed. And then the measured and simulated results are represented.
The internal small chip antenna for IMT-2000 band is proposed. It has the measured impedance bandwidth of 14% and the measured maximum gain of 1.3dBi. In addition, it shows omni-directional radiation pattern similar to that of monopole so that it can be applicable to IMT-2000 applications
Also, an antenna applicable to dual band of PCS and IMT-2000 services attracting much attention in recent years is proposed. The earlier proposed antenna is difficult to fabricate and requires relatively high fabrication costs. However, the proposed antenna in this phase can be fabricated with FR-4 material, which is used to make Printed Circuit Boards (PCBs), through etching process. Therefore it may be highly competitive since it can be easily fabricated and need relatively low fabrication costs. The measured results of the proposed antenna show the impedance bandwidth of 21.4% and the maximum gain of 2.6dBi. It also shows omni-directional radiation pattern so that it is applicable to PCS/IMT-2000 dual band.
When an antenna is built in a handset case, its impedance bandwidth may affect so that be out of the desired band. In consideration of this impact the antenna is redesigned. The measured results show the impedance bandwidth of 25.9% and the maximum gain of 2.15dBi. In the same manner, the omni-directional radiation pattern is obtained.
Finally, the antenna with built-in source was ...