Please use this identifier to cite or link to this item:
Designs of Reconfigurable Microstrip Antennas with Polarization and Frequency Diversities(2/2)
Aperture-coupled microstrip antenna;Reconfigurable antenna;Polarization diversity
|Issue Date: ||2012-06-05T02:02:36Z
The designs of an aperture-coupled microstrip antenna with switchable polarization and frequency are studied in the two-year project. A single-fed reconfigurable microstrip antenna that can provide various polarization diversities at the same operating frequency will be first investigated. The antenna is excited by a microstrip feed line through aperture coupling. When two PIN diodes are used to respectively reconfigure the coupling slot and the open stub of the feed line, the polarization of the microstrip antenna can be switched between vertical and horizontal polarizations. For the reconfigurable antenna with the linear polarization (LP) diversity, it can be converted to a circularly-polarized (CP) antenna with switchable polarization sense by introducing a perturbation segment. Moreover, an antenna with a quadri-polarization diversity will be developed from the structure of the switchable CP microstrip antenna. Several problems for the proposed polarization reconfigurable antenna will be also addressed. The design methods of a dual-frequency microstrip antenna capable of switching polarization sense between two orthogonal polarizations will be investigated in the second year. Referring the reconfigurable antenna with the LP diversity, studied in the first year, it is expected that the frequency ratio of the operating frequencies of the two LP modes can be varied by changing the aspect ratio of the radiating patch or embedding a thin slot into a square radiating patch. To achieve a switchable CP antenna with frequency agility, a new antenna structure will be proposed. The proposed antenna is fed by a microstrip line through the coupling of an aperture in the ground plane. First, it is found that a CP mode can be excited when the radiating patch is square and an open-ring slot is used as the coupling aperture. Then, by truncating the radiating patch, another CP mode can be obtained. The two CP modes have reversed polarization senses, and their operating frequencies are different. The key parameters which can change the frequency ratios of the two operating frequencies will be also explored. For the reconfigurable antennas studied in this project, several prototypes integrated with voltage-controlled diodes will be constructed and measured to exhibit their characteristics.
|Relation: ||計畫編號:NSC97-2221-E018-005-MY2; 研究期間:200908- 201007|
|Appears in Collections:||[電機工程學系] 國科會計畫|
Files in This Item:
All items in NCUEIR are protected by copyright, with all rights reserved.