Applications of Measurement of 3D Antenna Patterns and Evaluation of Antenna Characteristics

• Main Authors: Shih-Huang Wu, 吳適煌
• Other Authors: Jhin-Fang Huang
• Format: Others
• Language: en_US
• Published: 2007
• Online Access: http://ndltd.ncl.edu.tw/handle/49877614933923342767

碩士 === 國立臺灣科技大學 === 電子工程系 === 95 === Usually, E-plane and H-plane polar patterns are used to represent the antenna radiation characteristics. But 3D antenna pattern has capability to exhibit more radiation characteristics than 2D patterns such as peak gain, directivity, total radiated power, and radiation efficiency, because 2D polar patterns containing only two cuts can not exhibit the spatial characteristics completely. In this thesis, two methods of 3D antenna pattern measurement (Conical-Cut Method and Great-Circle Method), which can contain 35 cuts to exhibit spatial characteristics more completely, are introduced and discussed. Besides, a simple and fast alternative approach utilizing 2D patterns to construct 3D patterns is presented, due to a higher cost of the build and longer test duration of 3D pattern measurement. Revolving the E1-plane pattern around the Z-axis along the trace of H-plane pattern can obtain other E-plane patterns to construct a similar 3D pattern. The measured 3D pattern and the calculated 3D pattern using 2D patterns will be analyzed and discussed. The peak gain may not occur at either three plane patterns. If only plane patterns are measured, the peak gain might be missed. The antenna radiation efficiency has to be obtained by either the 3D pattern measurement or calculation. The study cases in this thesis, the deviation of efficiency is within 12%. In addition, an application for a WLAN/WiMAX antenna is discussed, from the antenna design to measurement and calculated of 3D antenna patterns, and the antenna characteristics obtained by them are analyzed and compared. Detail designs of the proposed antenna are described. The measured and calculated 3D patterns as well as antenna characteristics are also analyzed.