以缺陷型接地結構設計之2.4GHz與5.2GHz雙頻帶通濾波器

A Dual-Band Bandpass Filter Using Defected Ground Structure (DGS) Coupled Resonators at 2.4GHz and 5.2GHz

陳武男(Wu-Nan Chen) ； 林鴻暐(Hong-Wei Lin) ； 黃建銘(Jian-Ming Hang) ； 李可方(Ke-Fang Li)

《2008資通技術管理與應用會議》 2008 (2008/12) Pp. 6-20

摘要

本文是以微帶傳輸線原理，搭配開迴路螺旋型缺陷接地結構(Defected Ground Structure, DGS)，設計出頻率為2.4GHz與5.2GHz雙頻帶通濾波器(Dual-Band Bandpass Filter)，利用缺陷型接地結構與螺旋型式達到縮小傳統微帶線濾波器的體積的目的。並可藉由調整DGS的尺寸大小與距離，改變共振槽長度與耦合量，可控制2.4GHz與5.2GHz的中心頻率和頻率響應，中心頻率隨DGS長度增加而往低頻移動。模擬的結果比較，顯示其頻率響應具有極低的傳輸零點、量測結果顯示具有良好的反射損失(17.36dB @ 2.4GHz)、(17.76dB @ 5.2GHz)與插入損失(1.16dB @ 2.4GHz)、(2.7dB @ 5.2GHz)等優點，且在頻寬與頻率響應圖上充分顯示出符合於無線區域網路(Wireless LAN)IEEE 802.11a/b/g之規範。

關鍵字

DGS ； Wireless LAN ； Dual-Band

並列摘要

This paper proposes a dual-band bandpass filter using open loop defected ground structure (DGS) as main resonance structures and two 50-ohm transmission lines as taping. The dual-band bandpass filter operating at 2.4 and 5.2GHz is able to reduce filter size by using the spiral defected ground structure. Adjusting the DGS dimension and distance can simultaneously control the lower and upper bands. In addition, the cross coupling among taping lines and DGS structures is introduced so that two transmission zeros are generated between the two passbands to achieve a high out-of-band rejection. The simulation results closely agree with the measured results. The measurement shows high return losses of 17.36 dB at 2.4 GHz and 17.76 dB at 5.2 GHz, and acceptable insertion losses of 1.16 dB at 2.4 GHz and 2.7 dB at 5.2 GHz. The bandwidth and frequency response comply with WLAN (Wireless LAN) IEEE 802.11a/b/g standard.

並列關鍵字

DGS ； Wireless LAN ； Dual-Band