Research On Miniaturized Planar Inverted-F Antenna

Antenna is one of the key components in wireless communication;its performance determinates the quality of communication system.With the great development of wireless communication and the improvement of integrated circuits, there come great demands of miniaturized and multi-band antennas with broadband property.Planar inverted-F antenna consists of metal ground,radiating patch,short circuit patch and feeding line.PIFA antenna,which has the features of compact size, low profile,small weight,low cost,easy to fabricate and easy to be integrated with microwave circuits,has been applied widely.This paper mainly does research on miniaturization of PIFA antenna.Based on existed studies,two kinds of PIFA structures have been proposed through electromagnetic simulation software.The novel antennas have been fabricated and measured.The measured results agree well with the simulated results.These prove the validity of the designs in this thesis.The main work and creative points of this thesis are as follows:(1)Make an introduction about the current situation of PIFA research.The configuration and principle of PIFA have been analyzed in detail.Make an emphasis on introducing electric parameters and miniaturization of PIFA.(2)An improved double-patch miniaturized PIFA antenna applied to 2.4GHz frequency defined by WLAN 802.11a protocol is proposed.The size of the antenna is15×15×5mm~3.By exchanging locations of upper patch and under patch,the antenna further reduces the height.The return loss,voltage standing wave ratio,radiation pattern, peak gain and current distribution are analyzed and discussed.The antenna has been fabricated and measured.Measured and simulated results show good agreement.(3)A novel triple-band miniaturized PIFA structure is proposed for WCDMA frequency band and WLAN frequency band defined by WLAN802.11b.The size of the antenna is 17×12×10mm~3.The return loss,voltage standing wave ratio,radiation pattern,peak gain and current distribution are analyzed.Also,the antenna is fabricated and measured.Measured and simulated results show good agreement.The results show that the proposed antennas in this thesis have good performance and can meet the demands of the hand-set mobile terminals.