Title:
SURFACE WAVE DEVICES WITH LOW PASSBAND RIPPLE
Document Type and Number:
WIPO Patent Application WO2004054102
Kind Code:
B1
Abstract:
Very low passband ripple is provided in a wide bandwidth high frequency SAW FIR filter using slanted finger IDTs by one or more of three techniques: cancelling regenerated SAWs at parallel-connected input IDTs of two SAW filters which are similar except for a quarter-wavelength difference in spacing of the input and output IDTs, this difference varying with wavelength across the IDT aperture; shaping edges of shield electrodes to provide quarter-wavelength differences in, and hence cancellation of, SAWs reflected at the edges, the differences varying with wavelength across the IDT aperture; and making pairs of slanted shield electrodes symmetrical to compensate for refraction of SAWs by the shield electrodes.
Inventors:
JIAN CHUN-YUN
BEAUDIN STEVE A
SYCHALEUN SOMSACK
BEAUDIN STEVE A
SYCHALEUN SOMSACK
Application Number:
PCT/CA2003/001712
Publication Date:
September 10, 2004
Filing Date:
November 06, 2003
Export Citation:
Assignee:
NORTEL NETWORKS LTD (CA)
International Classes:
H03H9/00; H03H9/02; H03H9/145; H03H9/64; (IPC1-7): H03H9/145; H03H9/02
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