声表面波低插入损耗滤波器的研制(Ⅱ)——横向耦合谐振滤波器

详细信息

Design and performance of SAW low insertion loss filters (Ⅱ) Transversely-Coupled Resonator Filter

摘要: 目前移动通信窄带低插损高阻带抑制的滤波器有极大需求,而横向模式耦合谐振滤波器是实现这些性能的最佳方案之一。在理论上,本文应用陈东培和Hartmann等提出的耦合模型理论模型对这种滤波器进行了分析设计,在实验上,以ST石英为基底材料,设计制作了152.55 MHz频率的器件,器件性能接近目前国外已报道同类器件的水平,最低插损达2.7dB,阻带抑制约60dB相对带宽0.5‰~0.75‰。

Abstract: Currently the mobile communication system has a great need of the filter with narrow bandwidth,low loss and high rejection.SAW transversely-coupled resonator filter (T CRF) is t he optimum physical implementations of the filter above mentioned.In this papert we first analyzed theoretically TCRF using Coupling-of-Modes model presented by Chen & Hartmann et al.The experimental resultsof the filter fabricated on ST Quartz substrate is given.The device achieved favorable characteristics with an insertion loss of 2.7 dB,a sidelobe rejection of about 60 dB,a fractional bandwidth of about 0.5% and a very flat passband.