下載電子全文宣告This thesis is authorized to indicate in-campus access at one year and off-campus not accessible
You can not download at the moment.
Your IP address is 184.108.40.206
The defense date of the thesis is 2005-07-20
The current date is 2017-11-25
This thesis will be accessible at off-campus not accessible
URN etd-0720105-093453 Statistics This thesis had been viewed 1658 times. Download 17 times. Author Chih-Hsien Chiu Author's Email Address No Public. Department Communication Engineering Year 2004 Semester 2 Degree Master Type of Document Master's Thesis Language English Page Count 58 Title HIGH GAIN PARTIALLY REFLECTIVE SURFACE (PRS) ANTENNAS Keyword partially reflective surface frequency selective surface antenna antenna frequency selective surface partially reflective surface Abstract We present experimental results on partially reflective surface (PRS) antennas using dipoles and patches as radiating elements. On contrary to a conventional PRS, we introduce the tapered partially reflective surface (TPRS). TPRS is an unequally spaced PRS with smaller element spacing on the central region than on the edge region. Usually, amplitude of reflection coefficient from a PRS depends on its element spacing. Therefore, difference in reflection coefficient from the central and from the edge regions is expected for the TPRS. It is studied that the said difference can provide a substantial tapering effect.
Evidence of the tapering effect is that the average side lobes levels of TPRS are lower than those of PRS. For TPRS using patches as elements, this side lobe reduction is apparent over wide range of beam directions. For dipoles, side lobe reduction is restricted near main beam directions. The dipole array is considered to be easily influenced by the diffraction pattern so that the reduction in side lobe levels is not obvious as expected.
One advantage took from the reduction in side lobe levels is that we can further increase the gain from an optimized PRS. In one example, we can have a gain of 23dBi from a TPRS on contrast to 21.8dBi from a PRS though the two antennas are of equal size.
Advisor Committee The-Nan Chang - advisor
Po-Wen Hsu - co-chair
Shih-Chieh Chao - co-chair
Files Date of Defense 2005-06-24 Date of Submission 2005-07-20