Abstract:
Die Erfindung betrifft ein mit akustischen Oberflächenwellen arbeitendes elektronisches Bauelement mit einem unsymmetrischen Eingang und einem vorzugsweise symmetrischen Ausgang, mit einer DMS-Spur (DMS = Double Mode Surface Acoustic Wave), die zumindest einen endständigen Wandler und zumindest einen Koppel-Wandler aufweist, und einem Zweitor-Resonator, der zumindest zwei Serien-Wandler aufweist, wobei die Koppel-Wandler der DMS-Spur jeweils mit einem der Wandler des Zweitor-Resonators in Reihe geschaltet sind. Durch den Einsatz der erfindungsgemässen Verschaltung der Spuren gelingt es insbesondere, eine geringe Einfügedämpfung bei einer hohen Unterdrückung im Sperrbereich eines Bandpassfilters zu erzielen, den Platzbedarf für die Bauelement-Strukturen gering zu halten und ggf. gleichzeitig im Filter die Funktion eines Baluns zu realisieren.
Abstract:
A surface acoustic wave apparatus comprising a ladder-type multi-staged connection of surface acoustic wave resonators has two or more periods of the comb-shaped drive electrodes (10) of parallel resonators (P1-P3), two or more periods of the comb-shaped drive electrodes (10) of series resonators (S1-S3), the periods of reflection electrodes (12, 14) installed on both sides of the comb-shaped drive electrodes remaining are different from the periods of the comb-shaped drive electrodes, and two or more capacitances of the parallel resonators and those of the series resonators.
Abstract:
A branching filter comprising two surface acoustic wave filters with different band center frequencies and a phase matching circuit for matching the phases of the two surface acoustic wave filters with each other, wherein one of the surface acoustic wave filters is a ladder type surface acoustic wave filter, and the other includes a plurality of double mode type surface acoustic wave filters parallel connected to one another.
Abstract:
An acoustic wave filter (10) and a method (30) of forming the acoustic wave filter (10) are disclosed. The acoustic wave filter includes a substrate (20) supporting a first die (18) and a second die (18). The first die (18) and second die (18) include either a Surface Acoustic Wave (SAW) resonator or a Bulk Acoustic Wave (BAW) resonator, wherein one of the resonators is configured as a series resonator (12) of the acoustic wave filter (10) and the other resonator is configured as a shunt resonator (14) of the acoustic wave filter (10).
Abstract:
The invention relates to a high frequency surface wave filter comprising reactance elements, which is particularly suitable for use in the mobile radio telephone service. Said filter is balanced on both sides, is electrically symmetrical and comprises a quadripolar reactance series element which can be configured from two bipolar reactance elements or one quadripolar reactance series element and a resonator. One contact rail of each reactance element is connected to the input side of the filter and the other contact rail is connected to the output side of the filter.
Abstract:
The invention relates to a high frequency surface wave filter comprising reactance elements, which is particularly suitable for use in the mobile radio telephone service. Said filter is balanced on both sides, is electrically symmetrical and comprises a quadripolar reactance series element which can be configured from two bipolar reactance elements or one quadripolar reactance series element and a resonator. One contact rail of each reactance element is connected to the input side of the filter and the other contact rail is connected to the output side of the filter.
Abstract:
An acoustic wave ladder filter with lossy inductances (42) connected in parallel with resonators (40). Shunt sections of the ladder filter include impedance inverters having pass frequencies within the stopband of series resonators (33, 34, 34). The filter additionally includes variable capacitors (44) connected in parallel with the inductances to provide adjustment capabilities. The use of lossy inductances (42) actually increases effective coupling coefficient of the filter and improves insertion loss thereby allowing improved design flexibility.
Abstract:
The edge steepness of a pass band in a SAW filter comprising at least three series or parallel interconnected resonators is improved by providing several resonators with varying interdigital converter finger periodicities.
Abstract:
The invention concerns a surface wave filter for asymmetrical/symmetrical and symmetrical/asymmetrical operating mode with interdigital output transducers (IDT2, IDT4) connected in series.