使用低溫共燒陶瓷製程設計無線網路用差動帶通濾波器和差動雙工器

Abstract

在本論文提出應用於雙頻無線區域網路頻段差動帶通濾波器和差動雙工器之設計。假若在電路中使用平衡式架構，則可省去balun，且平衡式架構具有使用虛擬接地以改善較差的實際接地，並降低同模雜訊干擾等優點。差動帶通濾波器設計中，再加上兩個零點，可改善帶通濾波器的效能，另外在差動雙工器設計中，加入LC共振器，對於雙工器的兩個頻帶(2.4GHz和5.2GHz)可提供良好的隔離。 在設計新的帶通濾波器和雙工器中，採用LTCC (low-temperature co-fired ceramics)的製程，相較於一般如FR4的板材,此基材在微波頻具有較低之正切損失，並具有多層結構有利於平衡式傳輸線的設計。

In the paper, we present a new balanced filter and a balanced diplexer for dual-band wireless local-area network (WLAN). By using the balanced-type circuit, balun can be eliminated. The balanced circuit can also improve the poor ground and suppress the common-mode interference. In addition, this filter which uses two finite transmission zeros can improve the filter rolloff rate near passband and the diplexer which uses LC resonator can obtain better isolation. The LTCC (low temperature co-fired ceramic) is chosen for our component implementation for its low loss and multi-layer structure, which will give better insertion loss and give more freedom in balanced-type device design.