Design of SAW Filters for WLAN

• Main Authors: Teng-Kai Chen, 陳登凱
• Other Authors: Jean-Fu Kiang
• Format: Others
• Language: en_US
• Published: 2006
• Online Access: http://ndltd.ncl.edu.tw/handle/67982804281030601609

碩士 === 國立臺灣大學 === 電信工程學研究所 === 94 === In this thesis, coupling-of-modes (COM) approach and equivalent circuit model (ECM) are applied to design surface-acoustic wave (SAW) filters for various applications. A ladder-type SAW filter at IEEE 802.11a WLAN band is designed and the chip size is 214 × 115 μm2. An RF filter for unlicensed band of WiMAX and 802.11b WLAN is proposed and the chip size is 431 × 145 μm2. A miniaturized low-loss SAW duplexer has been developed for the WiMAX band and the chip size is 295 × 226.5 μm2. A six-channel low-loss switchable SAW filter bank is designed for the WiMAX system. It has the insertion loss of less than 1.8 dB, channel bandwidth of 20 MHz, stopband rejection of more than 35 dB, and the chip size is 3 × 1.7 mm2. Those SAW filters are designed on 42 YX-LiTaO3 substrate with aluminum (Al) electrodes. Sensitivity study has also been conducted. i