Study of Miniaturized Antenna by Using Magnetic Materials

• Main Authors: Ying-Jie Lu, 盧穎潔
• Other Authors: Lih-Shan Chen
• Format: Others
• Language: zh-TW
• Published: 2011
• Online Access: http://ndltd.ncl.edu.tw/handle/18948294219629347053

碩士 === 義守大學 === 電子工程學系碩士班 === 99 === Miniaturied microstrip patch antenna can be fabricated by using high permittivity substrates or tuning the shape and dimension of the antenna patterns. Although high permittivity substrate is beneficial for compact size, it also with the disadvantage of narrow bandwidth and low radiation efficiency. Magnetic materials can lead to antenna miniaturization, enhanced bandwidth and tunable resonant frequency. This study introduces BaCo-ferrite magnetic films to tune electrical properties of a patch antenna by loading single layer and multilayer ferrite films above the patch antenna and under the ground plane, and both sides of the FR4 substrate were investigated. The center resonant frequency of the unloaded patch antenna is measured at 2.47GHz with a bandwidth of 25MHz. However, with ferrite loading of above the patch antenna, this frequency is shown to be tunable within a range of 45-70MHz, and with ferrite loading of under the ground plane, this frequency is shown to be tunable within a range of 60-90MHz, and with ferrite loading of both side of the substrate, this frequency is shown to be tunable within a range of 70-160MHz.