Use of the Fan-Shaped Idts – Efficient Method for Creating the Wideband Saw Filters With a Low Insertion Loss and High Rectangularity of Frequency Response

Abstract

This paper presents an efficient method for creating the wideband SAW filters with high rectangularity, flat amplitude response and low insertion loss in passband – use of fan-shaped IDTs with inclined electrodes. The authors consider the approaches for realization of the fan-shaped filters. The quantitative and qualitative characteristics of the fan-shaped SAW filters with a relative bandwidth ∆f/f0 = 4–75 %, shape factor 1,1–1,96 and insertion loss of 5–18 dB are given for each approach.