Ladder‐type filter based on bulk acoustic wave resonators with improved out‐of‐band rejection

Filters based on bulk acoustic wave (BAW) resonators are called to replace actual surface acoustic wave filters. The transmission response of BAW‐based ladder‐type filters presents a steep rejection near the passband, but a poor out‐of‐band (OoB) rejection. This article describes how modifying the basic configuration of this type of filters, its OoB rejection can be improved. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 103–107, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23015

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